Patent Publication Number: US-9901710-B2

Title: Steering engagement catheter devices, systems, and methods

Description:
This international Patent Application claims priority to, and in at least some designated countries should be considered a continuation-in-part application of International Patent Application No. PCT/US2008/060870, filed Apr. 18, 2008, International Patent Application No. PCT/US2008/060487, filed Apr. 16, 2008, International Patent Application No. PCT/US2008/060513, filed Apr. 16, 2008, which claim priority to, and in at least some designated countries should be considered continuation-in-part applications of, International Patent Application No. PCT/US20081056666, filed Mar. 12, 2008, which claims priority to, and in at least some designated countries should be considered a continuation-in-part application of, International Patent Application No. PCT/US2008/053061, filed Feb. 5, 2008, which claims priority to, and in at least some designated countries should be considered a continuation-in-part application of, International Application Serial No. PCT/US2007/015207, filed Jun. 29, 2007, which claims priority to U.S. Provisional Patent Application Ser. No. 60/914,452, filed Apr. 27, 2007, and U.S. Provisional Patent Application Ser. No. 60/817,421, filed Jun. 30, 2006. Each of these applications are incorporated herein by reference. 
    
    
     BACKGROUND 
     Ischemic heart disease, or coronary heart disease, kills more Americans per year than any other single cause. In 2004, one in every five deaths in the United States resulted from ischemic heart disease. Indeed, the disease has had a profound impact worldwide. If left untreated, ischemic heart disease can lead to chronic heart failure, which can be defined as a significant decrease in the heart&#39;s ability to pump blood. Chronic heart failure is often treated with drug therapy. 
     Ischemic heart disease is generally characterized by a diminished flow of blood to the myocardium and is also often treated using drug therapy. Although many of the available drugs may be administered systemically, local drug delivery (“LDD”) directly to the heart can result in higher local drug concentrations with fewer systemic side effects, thereby leading to improved therapeutic outcomes. 
     Cardiac drugs may be delivered locally via catheter passing through the blood vessels to the inside of the heart. However, endoluminal drug delivery has several shortcomings, such as: (1) inconsistent delivery, (2) low efficiency of localization, and (3) relatively rapid washout into the circulation. 
     To overcome such shortcomings, drugs may be delivered directly into the pericardial space, which surrounds the external surface of the heart. The pericardial space is a cavity formed between the heart and the relatively stiff pericardial sac that encases the heart. Although the pericardial space is usually quite small because the pericardial sac and the heart are in such close contact, a catheter may be used to inject a drug into the pericardial space for local administration to the myocardial and coronary tissues. Drug delivery methods that supply the agent to the heart via the pericardial space offer several advantages over endoluminal delivery, including: (1) enhanced consistency and (2) prolonged exposure of the drug to the cardiac tissue. 
     In current practice, drugs are delivered into the pericardial space either by the percutaneous transventricular method or by the transthoracic approach. The percutaneous transventricular method involves the controlled penetration of a catheter through the ventricular myocardium to the pericardial space. The transthoracic approach involves accessing the pericardial space from outside the heart using a sheathed needle with a suction tip to grasp the pericardium, pulling it away from the myocardium to enlarge the pericardial space, and injecting the drug into the space with the needle. 
     For some patients with chronic heart failure, cardiac resynchronization therapy (“CRT”) can be used in addition to drug therapy to improve heart function. Such patients generally have an abnormality in conduction that causes the right and left ventricles to beat (i.e., begin systole) at slightly different times, which further decreases the heart&#39;s already-limited function. CRT helps to correct this problem of dyssynchrony by resynchronizing the ventricles, thereby leading to improved heart function. The therapy involves the use of an implantable device that helps control the pacing of at least one of the ventricles through the placement of electrical leads onto specified areas of the heart. Small electrical signals are then delivered to the heart through the leads, causing the right and left ventricles to beat simultaneously. 
     Like the local delivery of drugs to the heart, the placement of CRT leads on the heart can be challenging, particularly when the target placement site is the left ventricle, Leads can be placed using a transvenous approach through the coronary sinus, by surgical placement at the epicardium, or by using an endocardial approach. Problems with these methods of lead placement can include placement at an improper location (including inadvertent placement at or near scar tissue, which does not respond to the electrical signals), dissection or perforation of the coronary sinus or cardiac vein during placement, extended fluoroscopic exposure (and the associated radiation risks) during placement, dislodgement of the lead after placement, and long and unpredictable times required for placement (ranging from about 30 minutes to several hours). 
     Clinically, the only approved non-surgical means for accessing the pericardial space include the subxiphoid and the ultrasound-guided apical and parasternal needle catheter techniques, and each methods involves a transthoracic approach. In the subxiphoid method, a sheathed needle with a suction tip is advanced from a subxiphoid position into the mediastinum under fluoroscopic guidance. The catheter is positioned onto the anterior outer surface of the pericardial sac, and the suction tip is used to grasp the pericardium and pull it away from the heart tissue, thereby creating additional clearance between the pericardial sac and the heart. The additional clearance tends to decrease the likelihood that the myocardium will be inadvertently punctured when the pericardial sac is pierced. 
     Although this technique works well in the normal heart, there are major limitations in diseased or dilated hearts—the very hearts for which drug delivery and CRT lead placement are most needed. When the heart is enlarged, the pericardial space is significantly smaller and the risk of puncturing the right ventricle or other cardiac structures is increased. Additionally, because the pericardium is a very stiff membrane, the suction on the pericardium provides little deformation of the pericardium and, therefore, very little clearance of the pericardium from the heart. 
     As referenced above, the heart is surrounded by a “sac” referred to as the pericardium. The space between the surface of the heart and the pericardium can normally only accommodate a small amount of fluid before the development of cardiac tamponade, defined as an emergency condition in which fluid accumulates in the pericardium. Therefore, it is not surprising that cardiac perforation can quickly result in tamponade—which can be lethal. With a gradually accumulating effusion, however; as is often the case in a number of diseases, very large effusions can be accommodated without tamponade. The key factor is that once the total intrapericardial volume has caused the pericardium to reach the noncompliant region of its pressure-volume relation, tamponade rapidly develops. Little W. C., Freeman C. L. (2006). “Pericardial Disease.” Circulation 113(12): 1622-1632. 
     Cardiac tamponade occurs when fluid accumulation in the intrapericardial space is sufficient to raise the pressure surrounding the heart to the point where cardiac filling is affected. Ultimately, compression of the heart by a pressurized pericardial effusion results in markedly elevated venous pressures and impaired cardiac output producing shock which, if untreated, it can be rapidly fatal. Id. 
     The frequency of the different causes of pericardial effusion varies depending in part upon geography and the patient population. Corey G. R. (2007). “Diagnosis and treatment of pericardial effusion.” http://patients.uptodate.com. A higher incidence of pericardial effusion is associated with certain diseases. For example, twenty-one percent of cancer patients have metastases to the pericardium. The most common are lung (37% of malignant effusions), breast (22%), and leukemia/lymphoma (17%). Patients with WV, with or without AIDS, are found to have increased prevalence, with 41-87% having asymptomatic effusion and 13% having moderate-to-severe effusion. Strimel W. J. e. a. (2006). “Pericardial Effusion.” http://www.emedicine.com/meditopic1786.htm. 
     End-stage renal disease is a major public health problem. In the United States, more than 350,000 patients are being treated with either hemodialysis or continuous ambulatory peritoneal dialysis. Venkat A., Kaufmann K. R., Venkat K. (2006). “Care of the end-stage renal disease patient on dialysis in the ED.” Am J Emerg Med 24(7); 847-58. Renal failure is a common cause of pericardial disease, producing large pericardial effusions in up to 20% of patients. Task Force members, Maisch B, Seferovic P. M., Ristic A. D., Erbel R., Rienmuller R., Adler Y., Tomkowski W. Z., Thiene G., Yacoub M. H., ESC Committee for Practice Guidelines, Priori S. G., Alonso Garcia M. Blanc J.-J., Budaj A., Cowie M., Dean V., Deckers J., Fernandez Burgos E., Lekakis I., Lindahl B., Mazzotta O., Moraies J., Oto A., Smiseth O. A., Document Reviewers, Acar J., Arbustini E., Becker A. E., Chiaranda G., Hasin Y., Jenni R., Klein W., Lang I., Luscher T. F., Pinto F. I., Shabetai R., Simoons M. L., Soler Soler J., Spodick D. H. (2004). “Guidelines on the Diagnosis and Management of Pericardial Diseases Executive Summary: The Task Force on the Diagnosis and Management of Pericardial Diseases of the European Society of Cardiology.” Eur Heart J 25(7): 587-610. 
     Viral pericarditis is the most common infection of the pericardium. Inflammatory abnormalities are due to direct viral attack, the immune response (antiviral or anticardiac), or both. Id. Purulent (bacterial) pericarditis in adults is rare, but always fatal if untreated. Mortality rate in treated patients is 40%, mostly due to cardiac tamponade, toxicity, and constriction. It is usually a complication of an infection originating elsewhere in the body, arising by contiguous spread or haematogenous dissemination. Id. Other forms of pericarditis include tuberculous and neoplastic. 
     The most common secondary malignant tumors are lung cancer, breast cancer, malignant melanoma, lymphomas, and leukemias. Effusions may be small or large with an imminent tamponade. In almost two-thirds of the patients with documented malignancy pericardial effusion is caused by non-malignant diseases, e.g., radiation pericarditis, or opportunistic infections. The analyses of pericardial fluid, pericardial or epicardial biopsy are essential for the confirmation of malignant pericardial disease. Id. 
     Management of pericardial effusions continues to be a challenge. There is no uniform consensus regarding the best way to treat this difficult clinical entity. Approximately half the patients with pericardial effusions present with symptoms of cardiac tamponade. In these cases, symptoms are relieved by pericardial decompression, irrespective of the underlying cause. Georghiou G. P., Stamler A., Sharoni E., Eichman-Horn S., Berman M., Vidne B. A., Saute M. (2005). “Video-Assisted Thoracoscopic Pericardial Window for Diagnosis and Management of Pericardial Effusions.” Ann Thorac Sure 80(2): 607-610. Symptomatic pericardiac effusions are common and may result from a variety of causes. When medical treatment has failed to control the effusion or a diagnosis is needed, surgical intervention is required. Id. 
     The most effective management of pericardial effusions has yet to be identified. The conventional procedure is a surgically placed pericardial window under general anesthesia. This procedure portends significant operative and anesthetic risks because these patients often have multiple comorbidities. Less invasive techniques such as blind needle pericardiocentesis have high complication and recurrence rates. The technique of echocardiographic-guided pericardiocentesis with extended catheter drainage is performed under local anesthetic with intravenous sedation. Creating a pericardiostomy with a catheter in place allows for extended drainage and sclerotherapy. Echocardiographic-guided pericardiocentesis has been shown to be a safe and successful procedure when performed at university-affiliated or academic institutions. However, practices in community hospitals have rarely been studied in detail. Buchanan C. L., Sullivan V. V., Lampman R., Kulkami M. G. (2003). “Pericardiocentesis with extended catheter drainage: an effective therapy.” Ann Thorac Surg 76(3): 817-82. 
     The treatment of cardiac tamponade is drainage of the pericardial effusion. Medical management is usually ineffective and should be used only while arrangements are made for pericardial drainage. Fluid resuscitation may be of transient benefit if the patient is volume depleted (hypovolemic cardiac tamponade). 
     Surgical drainage (or pericardiectomy) is excessive for many patients. The best option is pericardiocentesis with the Seldinger technique, leaving a pigtail drainage catheter that should be kept in place until drainage is complete. Sagrista Sauleda J., Pemtanyer Miralda G., Soler Soler S. (2005). “[Diagnosis and management of acute pericardial syndromes].” Rev Esp Cardiol 58(7): 830-41. This less-invasive technique resulted in a short operative time and decreased supply, surgeon, and anesthetic costs. When comparing procedure costs of a pericardial window versus an echo-guided pericardiocentesis with catheter drainage at our institution, there was a cost savings of approximately $1,800/case in favor of catheter drainage. In an era of accelerating medical costs, these savings are of considerable importance. Buchanan C. L., Sullivan V. V., Lampman R., Kulkami M. G. (2003). “Pericardiocentesis with extended catheter drainage: an effective therapy.” Ann Thorac Surg 76(3): 817-82. 
     Clearly, there is a clinical need for a mini-invasive, safe and effective approach to treatment of pericardial effusion and tamponade. The present application takes advantage of a safe and effective pericardial access approach previously disclosed in combination with a special catheter used specifically for fluid drainage, fluid diagnosis, resuscitation and therapy delivery to treat the underlying cause of the effusion. 
     Thus, there is need for an efficient, easy to use, and relatively inexpensive device, system and technique that can be used to access the heart for local delivery of therapeutic and diagnostic substances, as well as of CRT leads and other types of leads. There is also a need for an efficient, easy to use, and relatively inexpensive device, system and technique that can be used to access a space containing fluid within a tissue to remove the fluid and to optionally deliver as substance if necessary. Such a device and/or device within a system may further provide, as disclosed herein, the user with the ability to “steer” the device and/or device within a system so that the device may be optimally positioned by the user within a body. 
     BRIEF SUMMARY 
     In at least one embodiment of a steering engagement catheter of the present disclosure, the steering engagement catheter comprises an elongated tube having a proximal end, a distal end, and a first wall positioned circumferentially along a length of the elongated tube, the elongated tube configured such that a delivery catheter is capable of at least partial insertion into the elongated tube, at least one steering wire having a proximal end and a distal end, the distal end of the steering wire coupled to the first wall of the elongated tube at or near the distal end of the elongated tube, and a controller operably coupled to the at least one steering wire at or near the proximal end of the at least one steering wire, the controller positioned along the elongated tube at or near the proximal end of the elongated tube. In another embodiment, operation of the controller causes the elongated tube to bend in response to movement of the at least one steering wire. In yet another embodiment, the at least one steering wire slidingly engages the elongated tube at one or more anchor positions along the elongated tube. In an additional embodiment, operation of the controller causes the at least one steering wire to slide along the one or more anchor positions, causing the elongated tube to bend in response to movement of the at least one steering wire. In yet an additional embodiment, the bend of the elongated tube bends an otherwise substantially straight elongated tube. 
     In at least one embodiment of a steering engagement catheter of the present disclosure, the bend of the elongated tube further bends an otherwise bent elongated tube. In another embodiment, the one or more anchor positions comprises two or more anchor positions, and wherein operation of the controller causes the at least one steering wire to slide along the two or more anchor positions, causing the elongated tube to bend in two or more places in response to movement of the at least one steering wire. In yet another embodiment, operation of the controller in first direction causes the at least one steering wire to slide along the one or more anchor positions in a direction toward the controller, causing the elongated tube to bend in a first direction. In an additional embodiment, operation of the controller in a second direction causes the at least one steering wire to slide along the one or more anchor positions in a direction away from the controller, causing the elongated tube to straighten at least partially from an initially bent configuration. In yet an additional embodiment, the at least one steering wire comprises two steering wires, and wherein the two steering wires slidingly engage the elongated tube at two or more anchor positions along the elongated tube. 
     In at least one embodiment of a steering engagement catheter of the present disclosure, the two or more anchor positions comprises four anchor positions, wherein one of the two steering wires slidingly engages the elongated tube at two of the four anchor positions and wherein the other steering wire slidingly engages the elongated tube at the other two of the four anchor positions, and wherein operation of the controller causes the two steering wires to slide along the four anchor positions, causing the elongated tube to bend in two places in response to movement of the two steering wires. In another embodiment, the controller comprises a handle coupled to the at least one steering wire at or near the proximal end of the at least one steering wire. In yet another embodiment, the at least one steering wire comprises two steering wires, wherein the controller comprises a first handle coupled to one of the two steering wires at or near the proximal end of that steering wire, and Wherein the controller comprises a second handle coupled to the other of the two steering wires at or near the proximal end of the other of the two steering wires. In an additional embodiment, the controller comprises a rotatable spool coupled to the at least one steering wire at or near the proximal end of the at least one steering wire, the rotatable spool operable to collect and dispense the at least one steering wire. In yet an additional embodiment, the rotatable spool is coupled to a rotatable dial so that rotation of the rotatable dial causes rotation of the rotatable spool, and wherein rotation of the rotatable spool causes the elongated tube to bend in response to movement of the at least one steering wire. 
     In at least one embodiment of a steering engagement catheter of the present disclosure, the at least one steering wire comprises two steering wires, wherein the controller comprises a first rotatable spool coupled to one of the two steering wires at or near the proximal end of that steering wire, and wherein the controller further comprises a second rotatable spool coupled to the other of the two steering wires at or near the proximal end of the other of the two steering wires, and wherein the first rotatable spool and the second rotatable spool are operable to each collect and dispense one of the two steering wires. In another embodiment, the first rotatable spool is coupled to a first rotatable dial so that rotation of the first rotatable dial causes rotation of the first rotatable spool, wherein the second rotatable spool is coupled to a second rotatable dial so that rotation of the second rotatable dial causes rotation of the second rotatable spool, and wherein rotation of the first rotatable spool and the second rotatable spool causes the elongated tube to bend in response to movement of the two steering wires. In yet another embodiment, the at least one steering wire comprises three steering wires, wherein the controller comprises a first rotatable spool coupled to one of the three steering wires at or near the proximal end of that steering wire, wherein the controller further comprises a second rotatable spool coupled to a second of the two steering wires at or near the proximal end of the second of the three steering wires, wherein the controller further comprises a third rotatable spool coupled to a third of the three steering wires at or near the proximal end of the third of the three steering wires, and wherein the first rotatable spool, the second rotatable spool, and the third rotatable spool are operable to each collect and dispense one of the three steering wires. In an additional embodiment, the steering engagement catheter further comprises a skirt operatively connected to the distal end of the elongated tube, the skirt comprising a proximal end having a circumference substantially similar to an outer circumference of the elongated tube, the Skirt further comprising a distal end having a circumference larger than the circumference of the elongated tube. In yet an additional embodiment, the elongated tube further comprises a second wall positioned circumferentially along the length of the elongated tube, wherein the first wall and the second wall form at least one suction channel along the length of the elongated tube between the first wall and the second wall, a vacuum port in communication with the proximal end of the elongated tube, the vacuum port being operatively connected to the at least one suction channel and capable of operative connection to a vacuum source, and a suction port in communication with the at least one suction channel at the distal end of the elongated tube, the suction port configured to engage a surface of a tissue. 
     In at least one embodiment of a steering engagement catheter of the present disclosure, the steering engagement catheter further comprises a skirt operatively connected to the distal end of the elongated tube at or near the suction port, the skirt comprising a proximal end having a circumference substantially similar to an outer circumference of the elongated tube, the skirt further comprising a distal end having a circumference larger than the circumference of the elongated tube, wherein the distal end of the skirt is operable to removably engage the surface of the tissue such that the skirt is capable of forming a reversible seal with the surface of the tissue when the vacuum source is operatively attached to the vacuum port. In another embodiment, the skirt comprises a deformable configuration. In yet another embodiment, the deformable configuration of the skirt is capable of expanding to an expanded configuration. In an additional embodiment, the expanded configuration is a frusto-conical configuration. In yet an additional embodiment, the expanded configuration is an irregular frusto-conical configuration. 
     In at least one embodiment of a steering engagement catheter of the present disclosure, the skirt has a collapsed configuration when the skirt is at least partially surrounded by a sleeve positioned circumferentially around the elongated tube, and wherein the skirt has an expanded configuration when the skirt is not surrounded by the sleeve. In another embodiment, the tissue engaged by the skirt of the steering engagement catheter comprises tissue surrounding a heart. In yet another embodiment, the skirt is capable of enlarging a pericardial space between the heart and a pericardial sac when the skirt is attached to an interior wall of the heart. In an additional embodiment, the steering engagement catheter further comprises at least one internal lumen support positioned within the at least one suction channel and attached to the first wall and the second wall, the at least one internal lumen support extending from the distal end of the elongated tube along at least a substantial portion of the length of the elongated tube. In yet an additional embodiment, the at least one internal lumen support comprises two internal lumen supports, and the at least one suction channel comprises two suction channels. In even another embodiment, the steering engagement catheter further comprises an injection channel formed along the length of the elongated tube, the injection channel having at its distal end at least one opening for administering a fluid to the tissue, the injection channel being capable of operable attachment to an external fluid source at the proximal end of the injection channel, such that fluid from the external fluid source can flow through the injection channel to the tissue when the external fluid source is operatively attached to the injection channel. In additional embodiments, the steering engagement catheter comprises one or more of the aforementioned elements relating to a steering engagement catheter and/or a system for use with a vacuum source for placing a lead of the present disclosure. 
     In at least one embodiment of a system for use with a vacuum source for engaging a tissue of the present disclosure, the system comprises a steering engagement catheter, comprising an elongated tube having a proximal end, a distal end, and first and second walls positioned circumferentially along a length of the elongated tube, the first and second walls defining first and second lumens extending between the proximal end and the distal end, a vacuum port located at or near the proximal end of the steering engagement catheter, the vacuum port being operatively connected to the first lumen of the steering engagement catheter and capable of operative connection to a vacuum source, a suction port located at or near the distal end of the steering engagement catheter, the suction port being operatively connected to the first lumen of the steering engagement catheter, the suction port configured to engage a surface of a tissue when the vacuum source is operatively attached to the vacuum port, at least one steering wire having a proximal end and a distal end, the distal end of the steering wire coupled to the first wall of the elongated tube at or near the distal end of the elongated tube, and a controller operably coupled to the at least one steering wire at or near the proximal end of the at least one steering wire, the controller positioned along the elongated tube at or near the proximal end of the elongated tube, and a delivery catheter comprising a hollow tube having a proximal end and a distal end, the delivery catheter configured such that the hollow tube is capable of insertion into the second lumen of the steering engagement catheter, and a needle located at the distal end of the delivery catheter, wherein the delivery catheter is operable to deliver a substance to a target site, in additional embodiments, the system comprises one or more of the aforementioned elements relating to a steering engagement catheter of the disclosure of the present application. 
     In at least one embodiment of a system for use with a vacuum source for engaging a tissue of the present disclosure, the system is capable of enlarging a pericardial space between the tissue and a pericardial sac that surrounds a heart by retracting the tissue away from the pericardial sac. In another embodiment, the system further comprises a sleeve comprising a proximal end, a distal end, and a lumen extending between the proximal end and the distal end of the sleeve, wherein the sleeve is positioned circumferentially around the steering engagement catheter, wherein the sleeve slidingly engages the steering engagement catheter. In yet another embodiment, the sleeve may be positioned at the distal end of the steering engagement catheter, and wherein the sleeve at least partially surrounds the skirt. In an additional embodiment, the deformable configuration of the skirt is collapsed when at least partially surrounded by the sleeve. In yet an additional embodiment, the sleeve is positioned along the steering engagement catheter so not to surround the skirt, wherein the skirt is capable of expanding to an expanded configuration. 
     In at least one embodiment of a system for use with a vacuum source for engaging a tissue of the present disclosure, the expanded configuration is a frusto-conical configuration. In another embodiment, the expanded configuration is a an irregular frusto-conical configuration. In yet another embodiment, the tissue comprises a portion of an atrial wall. In an additional embodiment, the tissue comprises a portion of an atrial appendage. In yet an additional embodiment, the tissue engaged by the engagement catheter is tissue surrounding a heart, and wherein the needle is positioned to be capable of piercing the tissue when the hollow tube is inserted into the second lumen and the suction port is attached to the tissue, such that, when the tissue is pierced, access to the pericardial space is achieved. 
     In at least one embodiment of a system for use with a vacuum source for engaging a tissue of the present disclosure, the system further comprises a guide wire for insertion into the pericardial space. In another embodiment, the needle comprises a hollow needle in communication with the hollow tube, and the guide wire is capable of insertion through the hollow tube and the hollow needle into the pericardial space. In yet another embodiment, the steering engagement catheter further comprises an injection channel in fluid communication with a third lumen of the steering engagement catheter extending between the proximal end and the distal end of the elongated tube, the injection channel being configured to administer a fluid to the tissue. In an additional embodiment, the fluid comprises an adhesive. In yet an additional embodiment, the injection channel is ring-shaped. 
     In at least one embodiment of a system for use with a vacuum source for engaging a tissue of the present disclosure, the steering engagement catheter further comprises an injection channel formed along the length of the steering engagement catheter, the injection channel having at its distal end at least one opening for administering a fluid to the targeted tissue, the injection channel being capable of operable attachment to an external fluid source at the proximal end of the injection channel, such that fluid from the external fluid source can flow through the injection channel to the targeted tissue when the external fluid source is operatively attached to the injection channel. In another embodiment, the needle comprises a needle wire for piercing the tissue. In yet another embodiment, the needle comprises a pressure tip needle. In an additional embodiment, the steering engagement catheter comprises a curvature along a length of the steering engagement catheter. In an additional embodiment, the curvature of the steering engagement catheter forms an angle that is approximately forty-five degrees. 
     In at least one embodiment of a system for use with a vacuum source for engaging a tissue of the present disclosure, the curvature of the steering engagement catheter forms an angle that is approximately ninety degrees, so that a portion of the steering engagement catheter is approximately perpendicular to another portion of the steering engagement catheter. In another embodiment, the curvature of the steering engagement catheter forms an angle so that a portion of the steering engagement catheter is approximately parallel to another portion of the steering engagement catheter. In additional embodiments, the system comprises one or more of the aforementioned elements relating to one or more systems of the present disclosure. 
     In at least one embodiment of a system for use with a vacuum source for placing a lead into a tissue of a heart, the system comprises a steering engagement catheter, comprising an elongated tube having a proximal end, a distal end, and first and second walls positioned circumferentially along a length of the elongated tube, the first and second walls defining first and second lumens extending between the proximal end and the distal end, at least one steering wire having a proximal end and a distal end, the distal end of the steering wire coupled to the first wall of the elongated tube at or near the distal end of the elongated tube, and a controller operably coupled to the at least one steering wire at or near the proximal end of the at least one steering wire, the controller positioned along the elongated tube at or near the proximal end of the elongated tube; a delivery catheter comprising an hollow tube having a wall and a first lumen, wherein the delivery catheter is configured such that the delivery catheter is capable of at least partial insertion into the second lumen of the steering engagement catheter, a lead having a tip at a distal end, the lead configured for at least partial insertion into the first lumen of the delivery catheter, and a vacuum port located at or near the proximal end of the steering engagement catheter, the vacuum port being operatively connected to the first lumen of the steering engagement catheter and capable of operative connection to the vacuum source, wherein the first lumen of the steering engagement catheter includes a suction port located at or near the distal end of the steering engagement catheter, the suction port being configured to removably attach to a targeted tissue on the interior of a wall of the heart, such that the suction port is capable of forming a reversible seal with the targeted tissue when the vacuum source is operatively attached to the vacuum port, and wherein the system is capable of enlarging a pericardial space between the targeted tissue and a pericardial sac that surrounds the heart by retracting the targeted tissue away from the pericardial sac. In additional embodiments, the system comprises one or more of the aforementioned elements relating to a steering engagement catheter and/or a system for use with a vacuum source for engaging a tissue of the disclosure of the present application. 
     In at least one embodiment of a system for use with a vacuum source for placing a lead into a tissue of a heart of the present disclosure, the first lumen of the delivery catheter extends from approximately the proximal end of the hollow tube to or near the distal end of the hollow tube, the first lumen of the delivery catheter having a bend, relative to the hollow tube, at or near the distal end of the hollow tube and an outlet through the wall of the hollow tube at or near the distal end of the hollow tube. In yet another embodiment, the bend of the first lumen of the delivery catheter forms an angle that is approximately 90-degrees. In an additional embodiment, the delivery catheter further comprises a second lumen extending from approximately the proximal end of the hollow tube of the delivery catheter to or near the distal end of the hollow tube, the second lumen of the delivery catheter having a bend, relative to the hollow tube, at or near the distal end of the hollow tube and an outlet through the wall of the hollow tube at or near the distal end of the hollow tube. In yet an additional embodiment, the bend of the second lumen of the delivery catheter forms an angle that is approximately 90-degrees. In another embodiment, the bend of the first lumen of the delivery catheter forms an angle that is approximately 90-degrees. 
     In at least one embodiment of a system for use with a vacuum source for placing a lead into a tissue of a heart of the present disclosure, the lead comprises a pacing lead, and the tip of the pacing lead has a substantially screw-like shape. In another embodiment, the tissue engaged by the skirt of the steering engagement catheter comprises heart tissue. In yet another embodiment, the skirt is capable of enlarging a pericardial space between the heart and a pericardial sac when the skirt is attached to an interior wall of the heart. In an additional embodiment, the system is capable of enlarging a pericardial space between the tissue and a pericardial sac that surrounds a heart by retracting the tissue away from the pericardial sac. In additional embodiments, the system comprises one or more of the aforementioned elements relating to one or more systems of the present disclosure. 
     In at least one embodiment of a method of engaging a targeted tissue of the present disclosure, the method comprises the steps of providing a steering engagement catheter, comprising an elongated tube having a proximal end, a distal end, and a first wall positioned circumferentially along a length of the elongated tube, the first wall defining a first lumen along the length of the elongated tube, at least one steering wire having a proximal end and a distal end, the distal end of the steering wire coupled to the first wall of the elongated tube at or near the distal end of the elongated tube, and a controller operably coupled to the at least one steering wire at or near the proximal end of the at least one steering wire, the controller positioned along the elongated tube at or near the proximal end of the elongated tube, and inserting the steering engagement catheter into a body such that the distal end of the steering engagement catheter is positioned at or near the targeted tissue. 
     In at least one embodiment of a method of engaging a targeted tissue of the present disclosure, the steering engagement catheter is capable of enlarging a pericardial space between the targeted tissue and a pericardial sac that surrounds a heart by retracting the targeted tissue away from the pericardial sac. In another embodiment, the step of inserting the steering engagement catheter into a body comprises the insertion of the steering engagement catheter such that the distal end of the steering engagement catheter is positioned inside the heart and distal end of the steering engagement catheter is in contact with the targeted tissue on the interior of a wall of the heart. In yet another embodiment, the method further comprises the step of operatively connecting a vacuum source to the first lumen such that the distal end of the steering engagement catheter is reversibly attached to the targeted tissue on the interior of a wall of the heart. 
     In at least one embodiment of a method of engaging a targeted tissue of the present disclosure, the step of inserting the steering engagement catheter into a body comprises the insertion of the steering engagement catheter such that the distal end of the steering engagement catheter is positioned inside the heart and the skirt is in contact with the targeted tissue on the interior of a wall of the heart. In another embodiment, the method further comprises the step of operatively connecting a vacuum source to the first lumen such that the skirt is reversibly attached to the targeted tissue on the interior of a wall of the heart. In yet another embodiment, the method further comprises the step of operating the controller to cause the elongated tube to bend in response to movement of the at least one steering wire. In additional embodiments, the method comprises one or more of the aforementioned elements and/or steps relating to one or more methods of the present disclosure. 
     In at least one embodiment of a method of engaging a targeted tissue of the present disclosure, the method comprises the steps of providing a system, the system comprising a steering engagement catheter comprising one or more elements of a steering engagement catheter of the present disclosure, and a delivery catheter comprising one or more elements of a delivery catheter of the present disclosure, and inserting the steering engagement catheter into a body such that the distal end of the steering catheter is positioned at or near the targeted tissue. 
     In at least one embodiment of a method of engaging a targeted tissue of the present disclosure, the step of inserting the steering engagement catheter into a body comprises the insertion of the steering engagement catheter such that the distal end of the steering engagement catheter is positioned inside the heart and distal end of the steering engagement catheter is in contact with the targeted tissue on the interior of a wall of the heart. In another embodiment, the method further comprises the step of operatively connecting a vacuum source to the first lumen such that the distal end of the steering engagement catheter is reversibly attached to the targeted tissue on the interior of a wall of the heart. In yet another embodiment, the step of inserting the steering engagement catheter into a body comprises the insertion of the steering engagement catheter such that the distal end of the steering engagement catheter is positioned inside the heart and the skirt is in contact with the targeted tissue on the interior of a wall of the heart. In an additional embodiment, the method further comprises the step of operatively connecting a vacuum source to the first lumen such that the skirt is reversibly attached to the targeted tissue on the interior of a wall of the heart. In yet an additional embodiment, the method further comprises the step of inserting the delivery catheter into the second lumen of the steering engagement catheter. 
     In at least one embodiment of a method of engaging a targeted tissue of the present disclosure, the method further comprises the step of piercing the targeted tissue on the interior of a wall of the heart with the needle. In another embodiment, the method further comprises the step of administering a substance into the pericardial space. In yet another embodiment, the method further comprises the steps of withdrawing the needle from the targeted tissue and administering a substance to the targeted tissue after withdrawal of the needle. In an additional embodiment, the substance comprises an adhesive for sealing a puncture wound in the targeted tissue. In yet an additional embodiment, the method further comprises the step of accessing the pericardial space by inserting a guide wire through the wall of the heart into the pericardial space. In another embodiment, the method further comprises the step of operating the controller to cause the elongated tube to bend in response to movement of the at least one steering wire. In additional embodiments, the method comprises one or more of the aforementioned elements and/or steps relating to one or more methods of the present disclosure. 
     In at least one embodiment of a method of placing a lead in a tissue of a heart of the present disclosure, the method comprising extending into a blood vessel a steering engagement catheter comprising one or more elements of a steering engagement catheter of the present disclosure and such that a distal end of an elongated tube of the steering engagement catheter is in contact with a targeted tissue on the interior of a wall of the heart, aspirating the targeted tissue such that the wall of the heart is retracted away from a pericardial sac surrounding the heart to enlarge a pericardial space between the pericardial sac and the wall of the heart, accessing the pericardial space through the targeted tissue, inserting at least a distal end of a guide wire into the pericardial space, inserting into the first lumen of the elongated tube and over the guide wire a delivery catheter comprising a first lumen, wherein the first lumen of the delivery catheter has an outlet at or near a distal end of the delivery catheter, advancing at least the distal end of the delivery catheter through the targeted tissue into the pericardial space, directing the delivery catheter such that the outlet of the first lumen of the delivery catheter is adjacent to the tissue of the heart, extending a lead through the first lumen of the delivery catheter into the tissue of the heart, withdrawing the delivery catheter from the pericardial space, and withdrawing the guide wire from the pericardial space. 
     In another embodiment, the delivery catheter further comprises a steering channel and a steering wire system located at least partially within the steering channel, and wherein the step of directing the delivery catheter such that the outlet of the first lumen of the delivery catheter is adjacent to the tissue of the heart comprises directing the delivery catheter with the steering wire system. In yet another embodiment, the method further comprises the step of extending a laser Doppler tip through a second lumen of the delivery catheter to the pericardial space. In an additional embodiment, the lead is a pacing lead, and wherein the steering wire system further comprises at least two steering wires attached to the delivery catheter inside the steering channel and a controller attached to the proximal ends of the at least two steering wires, the controller being capable of collecting and dispensing at least one of the at least two steering wires. 
     In at least one embodiment of a method of placing a lead in a tissue of a heart of the present disclosure, the step of directing the delivery catheter using the steering wire system comprises using the controller to tighten at least one of the at least two steering wires. In another embodiment, the method further comprises the step of inserting into the targeted tissue over the guide wire a plug having a first end, a second end, and a hole extending from the first end to the second end. In yet another embodiment, the hole of the plug is self-sealing after removal of the guide wire. In additional embodiments, the method comprises one or more of the aforementioned elements and/or steps relating to one or more methods of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  shows an embodiment of an engagement catheter and an embodiment of a delivery catheter as disclosed herein; 
         FIG. 1B  shows a percutaneous intravascular pericardial delivery using another embodiment of an engagement catheter and another embodiment of a delivery catheter as disclosed herein; 
         FIG. 2A  shows a percutaneous intravascular technique for accessing the pericardial space through a right atrial wall or atrial appendage using the engagement and delivery catheters shown in  FIG. 1A ; 
         FIG. 2B  shows the embodiment of an engagement catheter shown in  FIG. 2A ; 
         FIG. 2C  shows another view of the distal end of the engagement catheter embodiment shown in  FIGS. 2A and 2B ; 
         FIG. 3A  shows removal of an embodiment of a catheter as disclosed herein; 
         FIG. 3B  shows the resealing of a puncture according to an embodiment as disclosed herein; 
         FIG. 4A to 4C  show a closure of a hole in the atrial wall using an embodiment as disclosed herein; 
         FIG. 4D  shows another closure of a hole in cardiac tissue using another embodiment as disclosed herein; 
         FIG. 4E  shows yet another closure of a hole in cardiac tissue using another embodiment as disclosed herein; 
         FIG. 4F  shows still another closure of a hole in cardiac tissue using another embodiment as disclosed herein; 
         FIG. 5A  shows an embodiment of an engagement catheter as disclosed herein; 
         FIG. 5B  shows a cross-sectional view of the proximal end of the engagement catheter shown in  FIG. 5A ; 
         FIG. 5C  shows a cross-sectional view of the distal end of the engagement catheter shown in  FIG. 5A ; 
         FIG. 5D  shows the engagement catheter shown in  FIG. 5A  approaching a heart wall from inside of the heart: 
         FIG. 6A  shows an embodiment of a delivery catheter as disclosed herein; 
         FIG. 6B  shows a close-up view of the needle shown in  FIG. 6A ; 
         FIG. 6C  shows a cross-sectional view of the needle shown in  FIGS. 6A and 6B ; 
         FIG. 7  shows an embodiment of a delivery catheter as disclosed herein; 
         FIG. 8  shows an embodiment of a steering wire system within a steering channel; 
         FIG. 9A  shows another embodiment of a steering wire system as disclosed herein, the embodiment being deflected in one location; 
         FIG. 9B  shows the steering wire system shown in  FIG. 9A , wherein the steering wire system is deflected at two locations: 
         FIG. 9C  shows the steering wire system shown in  FIGS. 9A and 9B  in its original position; 
         FIG. 10  shows a portion of another embodiment of a steering wire system; 
         FIG. 11  shows a cross-sectional view of another embodiment of a delivery catheter as disclosed herein; 
         FIG. 12A  shows an embodiment of a system for closing a hole in cardiac tissue, as disclosed herein; 
         FIG. 12B  shows another embodiment of a system for closing hole in cardiac tissue, as disclosed herein; 
         FIG. 12C  shows another embodiment of a system for closing a hole in cardiac tissue, as disclosed herein; 
         FIG. 13  shows another embodiment of a system for closing a hole in cardiac tissue, as disclosed herein; 
         FIG. 14  shows another embodiment of a system for closing a hole in cardiac tissue, as disclosed herein; 
         FIG. 15A  shows another embodiment of a system for closing a hole in cardiac tissue, as disclosed herein; 
         FIG. 15B  shows the embodiment of  FIG. 15A  approaching cardiac tissue; 
         FIG. 15C  shows the embodiment of  FIGS. 15A-15C  deployed on the cardiac tissue; 
         FIG. 16A  shows an embodiment of a portion of an apparatus for engaging a tissue having a skirt positioned substantially within a sleeve, as disclosed herein; 
         FIG. 16B  shows another embodiment of a portion of an apparatus for engaging a tissue, as disclosed herein; 
         FIG. 16C  shows an embodiment of a portion of an apparatus for engaging a tissue having a skirt positioned substantially outside of a sleeve, as disclosed herein; 
         FIG. 17A  shows an embodiment of a portion of an apparatus for engaging a tissue that has engaged a tissue, as disclosed herein; 
         FIG. 17B  shows an embodiment of a portion of an apparatus for engaging a tissue having an expanded skirt that has engaged a tissue, as disclosed herein; 
         FIG. 18A  shows an embodiment of a portion of an apparatus for engaging a tissue having a collapsed skirt present within a sleeve, as disclosed herein; 
         FIG. 18B  shows an embodiment of a portion of an apparatus for engaging a tissue having an expanded skirt, as disclosed herein; 
         FIG. 19  shows an embodiment of a system for engaging a tissue, as disclosed herein; 
         FIG. 20A  shows an embodiment of a portion of an apparatus for engaging a tissue having a lead positioned therethrough, as disclosed herein; 
         FIG. 20B  shows an embodiment of a portion of an apparatus for engaging a tissue showing a needle, as disclosed herein; 
         FIG. 20C  shows the embodiment of  FIG. 20B  having a lead positioned therethrough. 
         FIG. 21A  shows an embodiment of a portion of an apparatus for removing fluid from a tissue, as disclosed herein; 
         FIG. 21B  shows an embodiment of a portion of an apparatus comprising grooves for removing fluid from a tissue, as disclosed herein; 
         FIG. 22  shows an embodiment of a portion of an apparatus for removing fluid from a tissue inserted within a heart, as disclosed herein; 
         FIG. 23  shows an embodiment of a steering engagement catheter, as disclosed herein; 
         FIG. 24  shows an embodiment of a system comprising a steering engagement catheter, as disclosed herein; and 
         FIG. 25A  shows an embodiment of a steering engagement catheter with a sleeve positioned thereon, as disclosed herein; 
         FIG. 25B  shows an embodiment of a steering engagement catheter with two bends, as disclosed herein; and 
         FIGS. 26A-26D  show cross-sectional views of exemplary embodiments of at least a portion of a steering engagement catheter, as disclosed herein. 
     
    
    
     DETAILED DESCRIPTION 
     it will be appreciated by those of skill in the art that the following detailed description of the disclosed embodiments is merely exemplary in nature and is not intended to limit the scope of the appended claims. 
     The disclosed embodiments include devices, systems, and methods useful for accessing various tissues of the heart from inside the heart. For example, various embodiments provide for percutaneous, intravascular access into the pericardial space through an atrial wall or the wall of an atrial appendage. In at least some embodiments, the heart wall is aspirated and retracted from the pericardial sac to increase the pericardial space between the heart and the sac and thereby facilitate access into the space. 
     Unlike the relatively stiff pericardial sac, the atrial wall and atrial appendage are rather soft and deformable. Hence, suction of the atrial wall or atrial appendage can provide significantly more clearance of the cardiac structure from the pericardium as compared to suction of the pericardium. Furthermore, navigation from the intravascular region (inside of the heart) provides more certainty of position of vital cardiac structures than does intrathoracic access (outside of the heart). 
     Access to the pericardial space may be used for identification of diagnostic markers in the pericardial fluid; for pericardiocentesis; and for administration of therapeutic factors with angiogenic, myogenic, and antiarrhythmic potential. In addition, as explained in more detail below, epicardial pacing leads may be delivered via the pericardial space, and an ablation catheter may be used on the epicardial tissue from the pericardial space. 
     In the embodiment of the catheter system shown in  FIG. 1A , catheter system  10  includes an engagement catheter  20 , a delivery catheter  30 , and a needle  40 . Although each of engagement catheter  20 , delivery catheter  30 , and needle  40  has a proximal end and a distal end,  FIG. 1A  shows only the distal end. Engagement catheter  20  has a lumen through which delivery catheter  30  has been inserted, and delivery catheter  30  has a lumen through which needle  40  has been inserted. Delivery catheter  30  also has a number of openings  50  that can be used to transmit fluid from the lumen of the catheter to the heart tissue in close proximity to the distal end of the catheter. 
     As shown in more detail in  FIGS. 2A, 2B, 2C , engagement catheter  20  includes a vacuum channel  60  used for suction of a targeted tissue  65  in the heart and an injection channel  70  used for infusion of substances to targeted tissue  65 , including, for example, a biological or non-biological degradable adhesive. As is shown in  FIGS. 2B and 2C , injection channel  70  is ring-shaped, which tends to provide relatively even dispersal of the infused substance over the targeted tissue, but other shapes of injection channels may be suitable. A syringe  80  is attached to injection channel  70  for delivery of the appropriate substances to injection channel  70 , and a syringe  90  is attached to vacuum channel  60  through a vacuum port (not shown) at the proximal end of engagement catheter  20  to provide appropriate suction through vacuum channel  60 . At the distal end of engagement catheter  20 , a suction port  95  is attached to vacuum channel  60  for contacting targeted tissue  65 , such that suction port  95  surrounds targeted tissue  65 , which is thereby encompassed within the circumference of suction port  95 . Although syringe  90  is shown in  FIG. 2B  as the vacuum source providing suction for engagement catheter  20 , other types of vacuum sources may be used, such as a controlled vacuum system providing specific suction pressures. Similarly, syringe  80  serves as the external fluid source in the embodiment shown in  FIG. 2B , but other external fluid sources may be used. 
     A route of entry for use of various embodiments disclosed herein is through the jugular or femoral vein to the superior or inferior vena cavae, respectively, to the right atrial wall or atrial appendage (percutaneously) to the pericardial sac (through puncture). 
     Referring now to  FIG. 1B , an engagement catheter  100  is placed via standard approach into the jugular or femoral vein. The catheter, which may be 4 or 5 Fr., is positioned under fluoroscopic or echocardiographic guidance into the right atrial appendage  110 . Suction is initiated to aspirate a portion of atrial appendage  110  away from the pericardial sac  120  that surrounds the heart. As explained herein, aspiration of the heart tissue is evidenced when no blood can be pulled back through engagement catheter  100  and, if suction pressure is being measured, when the suction pressure gradually increases. A delivery catheter  130  is then inserted through a lumen of engagement catheter  100 . A small perforation can be made in the aspirated atrial appendage  110  with a needle such as needle  40 , as shown in  FIGS. 1A and 2A . A guide wire (not shown) can then be advanced through delivery catheter  130  into the pericardial space to secure the point of entry  125  through the atrial appendage and guide further insertion of delivery catheter  130  or another catheter. Flouroscopy or echocardiogram can be used to confirm the position of the catheter in the pericardial space. Alternatively, a pressure tip needle can sense the pressure and measure the pressure change from the atrium (about 10 mmHg) to the pericardial space (about 2 mmHg). This is particularly helpful for transeptal access where puncture of arterial structures (e.g., the aorta) can be diagnosed and sealed with an adhesive, as described in more detail below. 
     Although aspiration of the atrial wall or the atrial appendage retracts the wall or appendage from the pericardial sac to create additional pericardial space, CO2 gas can be delivered through a catheter, such as delivery catheter  130 , into the pericardial space to create additional space between the pericardial sac and the heart surface. 
     Referring now to  FIG. 3A , the catheter system shown in  FIG. 1B  is retrieved by pull back through the route of entry. However, the puncture of the targeted tissue in the heart (e.g., the right atrial appendage as shown in  FIG. 3A ) may be sealed upon withdrawal of the catheter, which prevents bleeding into the pericardial space. The retrieval of the catheter may be combined with a sealing of the tissue in one of several ways: (1) release of a tissue adhesive or polymer  75  via injection channel  70  to seal off the puncture hole, as shown in  FIG. 3B ; (2) release of an inner clip or mechanical stitch to close off the hole from the inside of the cavity or the heart, as discussed herein; or (3) mechanical closure of the heart with a sandwich type mechanical device that approaches the hole from both sides of the wall (see  FIGS. 4A, 4B, and 4C ). In other words, closure may be accomplished by using, for example, a biodegradable adhesive material (e.g., fibrin glue or cyanomethaerylate), a magnetic system, or an umbrella-shaped nitinol stent. An example of the closure of a hole in the atrium is shown in  FIG. 3B . Engagement catheter  20  is attached to targeted tissue  95  using suction through suction port  60 . Tissue adhesive  75  is injected through injection channel  70  to coat and seal the puncture wound in targeted tissue  95 . Engagement catheter  20  is then withdrawn, leaving a plug of tissue adhesive  75  attached to the atrial wall or atrial appendage. 
     Other examples for sealing the puncture wound in the atrial wall or appendage are shown in  FIGS. 4A-4F . Referring now to  FIGS. 4A-4C , a sandwich-type closure member, having an external cover  610  and an internal cover  620 , is inserted through the lumen of engagement catheter  600 , which is attached to the targeted tissue of an atrial wall  630 . Each of external and internal covers  610  and  620  is similar to an umbrella in that it can be inserted through a catheter in its folded configuration and expanded to an expanded configuration once it is outside of the catheter. As shown in  FIG. 4A , external cover  610  is deployed (in its expanded configuration) on the outside of the atrial wall to seal a puncture wound in the targeted tissue, having already been delivered through the puncture wound into the pericardial space. Internal cover  620  is delivered through engagement catheter  600  (in its folded configuration), as shown in  FIGS. 4A and 4B , by an elongated delivery wire  615 , to which internal cover  620  is reversibly attached (for example, by a screw-like mechanism). Once internal cover  620  is in position on the inside of atrial wall  630  at the targeted tissue, internal cover  620  is deployed to help seal the puncture wound in the targeted tissue (see  FIG. 4C ). 
     Internal cover  620  and external cover  610  may be made from a number of materials, including a shape-memory alloy such as nitinol. Such embodiments are capable of existing in a catheter in a folded configuration and then expanding to an expanded configuration when deployed into the body. Such a change in configuration can result from a change in temperature, for example. Other embodiments of internal and external covers may be made from other biocompatible materials and deployed mechanically. 
     After internal cover  620  is deployed, engagement catheter  600  releases its grip on the targeted tissue and is withdrawn, leaving the sandwich-type closure to seal the puncture wound, as shown in  FIG. 4C . External cover  610  and internal cover  620  may be held in place using a biocompatible adhesive. Similarly, external cover  610  and internal cover  620  may be held in place using magnetic forces, such as, for example, by the inside face (not shown) of external cover  610  comprising a magnet, by the inside face (not shown) of internal cover  620  comprising a magnet, or both inside faces of external cover  610  or internal cover  620  comprising magnets. 
     In the embodiment shown in  FIGS. 4A, 4B, and 4C , the closure member comprises external cover  610  and internal cover  620 . However, in at least certain other embodiments, the closure member need not have two covers. For example, as shown in  FIG. 4D , closure member  632  is made of only one cover  634 . Cover  634  has a first face  636  and a second face  638 , and first face  636  is configured for reversible attachment to distal end  642  of delivery wire  640 . Closure member  632  may be made of any suitable material, including nitinol, which is capable of transitioning from a folded configuration to an expanded configuration. 
     In the embodiment shown in  FIG. 4E , a closure member  1500  comprises an external cover  1510  and an internal cover  1520  within a delivery catheter  1530 . External cover  1510  and internal cover  1520  are attached at a joint  1540 , which may be formed, for example, by a mechanical attachment or by a magnetic attachment. In embodiments having a magnetic attachment, each of the external cover and the internal cover may have a ferromagnetic component that is capable of magnetically engaging the other ferromagnetic component. 
     Delivery catheter  1530  is shown after insertion through hole  1555  of atrial wall  1550 . Closure member  1500  may be advanced through delivery catheter  1530  to approach atrial wall  1550  by pushing rod  1560 . Rod  1560  may be reversibly attached to internal cover  1520  so that rod  1560  may be disconnected from internal cover  1520  after closure member  1500  is properly deployed. For example, rod  1560  may engage internal cover  1520  with a screw-like tip such that rod  1560  may be easily unscrewed from closure member  1500  after deployment is complete. Alternatively, rod  1560  may simply engage internal cover  1520  such that: internal cover  1520  may be pushed along the inside of delivery catheter  1530  without attachment between internal cover  1520  and rod  1560 . 
     Closure member  1500  is advanced through delivery catheter  1530  until external cover  1510  reaches a portion of delivery catheter  1530  adjacent to atrial wall  1550 ; external cover  1510  is then pushed slowly out of delivery catheter  1530  into the pericardial space. External cover  1510  then expands and is positioned on the outer surface of atrial wall  1550 . When external cover  1510  is properly positioned on atrial wall  1550 , joint  1540  is approximately even with atrial wall  1550  within hole  1555 . Delivery catheter  1530  is then withdrawn slowly, causing hole  1555  to close slightly around joint  1540 . As delivery catheter  1530  continues to be withdrawn, internal cover  1520  deploys from delivery catheter  1530 , thereby opening into its expanded formation. Consequently, atrial wall  1550  is pinched between internal cover  1520  and external cover  1510 , and hole  1555  is closed to prevent leakage of blood from the heart. 
       FIG. 4F  shows the occlusion of a hole (not shown) in atrial wall  1600  due to the sandwiching of atrial wall  1600  between an external cover  1610  and an internal cover  1620 . External cover  1610  is shown deployed on the outside surface of atrial wall  1600 , while delivery catheter  1630  is deployed on the inside surface of atrial wall  1600 . As shown, rod  1640  is engaged with internal cover  1620 , and delivery catheter  1650  is in the process of being withdrawn, which allows internal cover  1620  to fully deploy. Rod  1640  is then withdrawn through delivery catheter  1630 . An engagement catheter (not shown) may surround delivery catheter  1650 , as explained more fully herein. 
     Other examples for sealing a puncture wound in the cardiac tissue are shown in  FIGS. 12-15 . Referring now to Ha  12 A, there is shown a plug  650  having a first end  652 , a second end  654 , and a hole  656  extending from first end  652  to second end  654 . Plug  650  may be made from any suitable material, including casein, polyurethane, silicone, and polytetrafluoroethylene. Wire  660  has been slidably inserted into hole  656  of plug  650 . Wire  660  may be, for example, a guide wire or a pacing lead, so long as it extends through the hole in the cardiac tissue (not shown). As shown in  FIG. 12A , first end  652  is covered with a radiopaque material, such as barium sulfate, and is therefore radiopaque. This enables the clinician to view the placement of the plug in the body using radiographic imaging. For example, the clinician can confirm the location of the plug during the procedure, enabling a safer and more effective procedure for the patient. 
     As shown in  FIG. 12A , first end  652  of plug  650  has a smaller diameter than second end  654  of plug  650 . Indeed, plug  680  shown  FIG. 12B  and plug  684  shown in  FIGS. 13 and 14  have first ends that are smaller in diameter than their respective second ends. However, not all embodiments of plug have a first end that is smaller in diameter than the second end. For example, plug  682  shown in  FIG. 12C  has a first end with a diameter that is not smaller than the diameter of the second end. Both types of plug can be used to close holes in cardiac tissue. 
     Referring again to  FIG. 12A , elongated shaft  670  has a proximal end (not shown), a distal end  672 , and a lumen  674  extending from the proximal end to distal end  672 . Although no catheter is shown in  FIG. 12A , plug  650 , wire  660 , and shaft  670  are configured for insertion into a lumen of a catheter see  FIG. 14 ), such as an embodiment of an engagement catheter disclosed herein. Plug  650  and shaft  670  are also configured to be inserted over wire  660  and can slide along wire  660  because each of lumen  656  of plug  650  and lumen  674  of shaft  670  is slightly larger in circumference than wire  660 . 
     As shown in  FIGS. 13 and 14 , shaft  672  is used to push plug  684  along wire  674  within elongated tube  676  to and into the hole in the targeted cardiac tissue  678 . Distal end  677  of elongated tube  676  is shown attached to cardiac tissue  678 , but distal end  677  need not be attached to cardiac tissue  678  so long as distal end  677  is adjacent to cardiac tissue  678 . Once plug  684  is inserted into the hole, wire  674  may be withdrawn from the hole in plug  684  and the interior of the heart (not shown) and shaft  672  is withdrawn from elongated tube  676 . In some embodiments, the plug is self-sealing, meaning that the hole of the plug closes after the wire is withdrawn. For example, the plug may be made from a dehydrated protein matrix, such as casein or ameroid, which swells after soaking up fluid. After shaft  672  is withdrawn, elongated tube  676  can be withdrawn from the heart. 
     It should be noted that, in some embodiments, the wire is not withdrawn from the hole of the plug. For example, where the wire is a pacing lead, the wire may be left within the plug so that it operatively connects to the CRT device. 
     Referring now to  FIG. 12B , there is shown a plug  680  that is similar to plug  684 . However, plug  680  comprises external surface  681  having a ridge  683  that surrounds plug  680  in a helical or screw-like shape. Ridge  683  helps to anchor plug  680  into the hole of the targeted tissue (not shown). Other embodiments of plug may include an external surface having a multiplicity of ridges surrounding the plug, for example, in a circular fashion. 
       FIGS. 15A-15C  show yet another embodiment of a closure member for closing a hole in a tissue. Spider clip  1700  is shown within catheter  1702  and comprises a head  1705  and a plurality of arms  1710 ,  1720 ,  1730 , and  1740 . Each of arms  1710 ,  1720 ,  1730 , and  1740  is attached at its proximal end to head  1705 . Although spider clip  1700  has four arms, other embodiments of spider clip include fewer than, or more than, four arms. For example, some embodiments of spider clip have three arms, while others have five or more arms. 
     Referring again to  FIGS. 15A-15C , arms  1710 ,  1720 ,  1730 , and  1740  may be made from any flexible biocompatible metal that can transition between two shapes, such as a shape-memory alloy (e.g., nitinol) or stainless steel. Spider clip  1700  is capable of transitioning between an open position (see  FIG. 15A ), in which the distal ends of its arms  1710 ,  1720 ,  1730 , and  1740  are spaced apart, and a closed position (see  FIG. 15C ), in which the distal ends of arms  1710 ,  1720 ,  1730 , and  1740  are gathered together. For embodiments made from a shape-memory alloy, the clip can be configured to transition from the open position to the closed position when the metal is warmed to approximately body temperature, such as when the clip is placed into the cardiac tissue. For embodiments made from other types of metal, such as stainless steel, the clip is configured in its closed position, but may be transitioned into an open position when pressure is exerted on the head of the clip. Such pressure causes the arms to bulge outward, thereby causing the distal ends of the arms to separate. 
     In this way, spider clip  1700  may be used to seal a wound or hole in a tissue, such as a hole through the atrial wall. For example,  FIG. 15B  shows spider clip  1700  engaged by rod  1750  within engagement catheter  1760 . As shown, engagement catheter  1760  has a bell-shaped suction port  1765 , which, as disclosed herein, has aspirated cardiac tissue  1770 . Cardiac tissue  1770  includes a hole  1775  therethrough, and suction port  1765  fits over hole  1775  so as to expose hole  1775  to spider clip  1700 . 
     Rod  1750  pushes spider clip  1700  through engagement catheter  1760  to advance spider clip  1700  toward cardiac tissue  1770 . Rod  1750  simply engages head  1705  by pushing against it, but in other embodiments, the rod may be reversibly attached to the head using a screw-type system. In such embodiments, the rod may be attached and detached from the head simply by screwing the rod into, or unscrewing the rod out of; the head, respectively. 
     In at least some embodiments, the spider clip is held in its open position during advancement through the engagement catheter by the pressure exerted on the head of the clip by the rod. This pressure may be opposed by the biasing of the legs against the engagement catheter during advancement. 
     Referring to  FIG. 15C , spider clip  1700  approaches cardiac tissue  1770  and eventually engages cardiac tissue  1770  such that the distal end of each of arms  1710 ,  1720 ,  1730 , and  1740  contacts cardiac tissue  1670 . Rod  1750  is disengaged from spider clip  1700 , and spider clip  1700  transitions to its closed position, thereby drawing the distal ends of arms  1710 ,  1720 ,  1730 , and  1740  together. As the distal ends of the arms are drawn together, the distal ends grip portions of cardiac tissue  1770 , thereby collapsing the tissue between arms  1710 ,  1720 ,  1730 , and  1740  such that hole  1775  is effectively closed. 
     Rod  1750  is then withdrawn, and engagement catheter  1760  is disengaged from cardiac tissue  1770 . The constriction of cardiac tissue  1770  holds hole  1775  closed so that blood does not leak through hole  1775  after engagement catheter  1760  is removed. After a relatively short time, the body&#39;s natural healing processes permanently close hole  1775 . Spider clip  1700  may remain in the body indefinitely. 
       FIGS. 16A, 16B, and 16C  show an embodiment of a portion of an apparatus for engaging a tissue as disclosed herein. As shown in  FIG. 16A , a sleeve  1800  is present around at least a portion of an engagement catheter  1810 . Sleeve  1800 , as described herein, may comprise a rigid or flexible tube having a lumen therethrough, appearing around the outside of engagement catheter  1810  and slidingly engaging engagement catheter  1810 , In at least the embodiment shown in  FIG. 16A , the distal end  1820  of engagement catheter  1810  comprises a skirt  1830 , shown in  FIG. 16A  as being housed within sleeve  1800 . A delivery catheter  1840  may be present within engagement catheter  1810  as shown to facilitate the delivery of a product (gas, liquid, and/or particulate(s)) to a target site. In this embodiment, delivery catheter  1840  is present at least partially within the lumen of engagement catheter  1810 , and engagement catheter is placed at least partially within the lumen of sleeve  1800 . 
     Referring now to  FIG. 16B , an embodiment of an apparatus as shown in  FIG. 16A  or similar to the embodiment shown in  FIG. 16A  is shown with sleeve  1800  being “pulled back” from the distal end of engagement catheter  1810 . As shown in  FIG. 16B , as sleeve  1800  is pulled back (in the direction of the arrow), skirt  1830  becomes exposed, and as sleeve  1800  is no longer present around skirt  1830 , skirt  1830  may optionally expand into a frusto-conical (“bell-shaped”) skirt  1830 . Skirt  1830  may be reversibly deformed (collapsed) when present within the lumen of sleeve  1800  as shown in  FIG. 16A  and in  FIG. 18A  described in further detail herein. It can be appreciated that many alternative configurations of Skirt  1830  to the frusto-conical configuration may exist, including an irregular frusto-conical configuration, noting that a configuration of skirt  1830  having a distal portion (closest to a tissue to be engaged) larger than a proximal position may benefit from suction of a larger surface area of a tissue as described in further detail herein. 
       FIG. 16C  shows an embodiment of an apparatus described herein having an expanded skirt  1830 . As shown in  FIG. 16C , sleeve  1800  has been pulled back (in the direction of the arrow) so that the expanded configuration of skirt  1830  may be present to engage a tissue (not shown). 
       FIGS. 17A and 17B  shown alternative embodiments of a portion of an apparatus for engaging a tissue as described herein.  FIGS. 17A and 17B  each show a sleeve  1800 , an engagement catheter  1810  having a skirt  1830 , and a delivery catheter  1840 . In each figure, skirt  1830  is shown engaging a surface of a tissue  1850 . In the embodiments shown in  FIGS. 17A and 17B , the relative sizes of the sleeves  1800 , engagement catheters  1810 , and delivery catheters  1840  are similar as shown, but the relative sizes of the skirts  1830  of the engagement catheters  1810  are clearly different. The exemplary embodiment of the portion of an apparatus for engaging a tissue shown in  FIG. 17A  comprises a skirt  1830  of the same or substantially similar relative size as the engagement catheter  1810 , meaning that the diameters of the engagement catheter  1810  and the skirt  1830  shown in  FIG. 17A  are approximately the same. Conversely, the exemplary embodiment of the portion of an apparatus for engaging a tissue shown in  FIG. 17B  comprises a skirt  1830  notably larger than the engagement catheter  1810 , meaning that the diameters of the engagement catheter  1810  and the skirt  1830  at its widest point shown in  FIG. 17B  are notably different. As shown in  FIG. 17B , as skirt  1830  extends from engagement catheter  1810  to tissue  1850 , the diameter of skirt  1830  increases. As such, skirt  1830  of the embodiment shown in  FIG. 17B  may engage a larger surface area of a tissue (shown by  1860 ) than the embodiment of the skirt  1830  shown in  FIG. 17A . The ability to engage a larger surface area of a tissue  1850  by skirt  1830  allows a better reversible engagement of a tissue  1850  when a vacuum is provided as described in detail herein. This improved suction allows a person using such an apparatus to more effectively engage a tissue  1850  than would otherwise be possible when skirt  1830  engages a smaller surface area of a tissue. 
       FIGS. 18A and 18B  show perspective views of an embodiment of a portion of an apparatus for engaging a tissue.  FIG. 18A  represents an embodiment whereby a skirt  1830  of an engagement catheter  1810  is positioned substantially within a sleeve  1800 .  FIG. 18B  represents an embodiment whereby a skirt  1830  of an engagement catheter  1810  is positioned outside s  1800 . As such, the positioning of skirt  1830  within sleeve  1800  can be seen in the embodiments of  FIGS. 16A and 18A , and the positioning of skirt  1830  outside of sleeve  1800  can be seen in the embodiments of  FIGS. 16C and 18B . 
     As shown in  FIG. 18A , skirt  1830  of engagement catheter  1810  is positioned within sleeve  1800 , whereby the configuration of skirt  1830  is collapsed so that skirt  1830  may fit within sleeve  1800 . As sleeve  1800  moves in the direction of the arrow shown in  FIG. 18B , skirt  1830  becomes exposed and its configuration is allowed to expand because there are no constraints provided by the inner wall of sleeve  1800 . 
     The embodiments shown in  FIGS. 18A and 18B  also show an exemplary embodiment of a configuration of an engagement catheter  1810 . As shown in  FIG. 18B , engagement catheter  1810  defines a number of apertures (representing lumens) present at the distal end of engagement catheter  1810  (at the proximal end of skirt  1830 ), including, but not limited to, one or more vacuum ports  1870  (representing the aperture at or near the distal end of a vacuum tube), and a delivery port  1880  (representing the aperture at or near the distal end of a delivery tube). A vacuum source (not shown) may be coupled to a suction port located at a proximal end of one or more vacuum tubes as described herein, whereby gas, fluid, and/or particulate(s) may be introduced into one or more vacuum ports  1870  by the introduction of a vacuum at a vacuum port. Gas, fluid, and/or particulate(s) may be introduced from delivery aperture  1880  to a tissue (not shown in  FIG. 18A or 18B ). 
     As shown by the exemplary embodiments of  FIGS. 17A and 17B , the ability for a user of such an apparatus for engaging a tissue to obtain proper suction depends at least in part on the relative placement of skirt  1830  and delivery catheter  1840  at or near a tissue  1850 . As described in detail herein regarding the exemplary embodiment shown in  FIG. 5D , if a vacuum source provides suction through one or more vacuum ports  1870  (shown in  FIGS. 18A and 18B ), but skirt  1830  has not effectively engaged a tissue  1850 , gas, fluid, and/or particulate(s) the area of tissue  1850  and/or gas, fluid and/or particulate(s) delivered via delivery catheter  1840  to the area of tissue  1850  may be aspirated by one or more vacuum ports  1870 . In a situation where skirt  1830  has effectively engaged a tissue  1850  but where delivery catheter  1840  has not engaged a tissue  1850 , any gas, liquid, and/or particulate(s) delivered by delivery catheter  1840  may be aspirated by one or more vacuum ports  1870 . In a situation where skirt  1830  and delivery catheter  1840  have effectively engaged a tissue  1850 , most, if not all, of any gas, liquid, and/or particulate(s) delivered by delivery catheter  1840  to tissue  1850  would not be aspirated by one or more vacuum ports  1870  as the placement of delivery catheter  1840  on or within tissue  1850  would provide direct delivery at or within tissue  1850 . 
     An exemplary embodiment of a system and/or device for engaging a tissue as described herein is shown in  FIG. 19 . As shown in  FIG. 19 , an exemplary apparatus shows a sleeve  1800  which has been moved in the direction of the arrow to reveal skirt  1830  at the distal end of engagement catheter  1810 , allowing skirt to resume an expanded, frusto-conical configuration. As shown in this embodiment, delivery catheter  1840  has been introduced at the proximal end of the apparatus (in the direction shown by the dashed arrow), allowing delivery catheter  1840  to exit out of a delivery lumen (not shown) at the distal end of engagement catheter  1840 . A needle  1890  may be present at the distal end of delivery catheter  1840 , facilitating the potential puncture of a tissue (not shown) to allow the distal end of delivery catheter  1840  to enter a tissue. 
     In addition, and as shown in the exemplary embodiment of  FIG. 19 , a lead  1900  may be introduced into delivery catheter  1840  (in the direction shown by the dashed arrow), whereby the distal end of lead  1900  may exit an aperture of needle  1890  and optionally enter a tissue and/or a lumen of a tissue. As described herein, any number of suitable types of leads  1900  may be used with the delivery catheters described herein, including sensing leads and/or pacing leads. A vacuum source  1910  may also provide a source of vacuum to such an apparatus to allow skirt  1830  to engage a tissue using suction. 
     The exemplary embodiment of an apparatus for engaging a tissue as shown in  FIG. 19  comprises an engagement catheter  1810  having a curvature. Such a curved engagement catheter  1810  allows a user of such an apparatus, for example, to insert a portion of the apparatus into a body or tissue from one direction, and engage a tissue with skirt  1830 , delivery catheter  1840 , needle  1890 , and/or lead  1900  from another direction. For example, a user may introduce a portion of an apparatus from one side of the heart, and the apparatus may engage the heart from a different direction than the direction of introduction of the apparatus. 
     It can also be appreciated that an exemplary embodiment of an apparatus of the present disclosure may be used to engage an internal portion of an organ. As previously referenced herein, such an apparatus may be used to engage the surface of a tissue. However, it can be appreciated that such a tissue may be an outer surface of any number of tissues, including, but not limited to, a heart, lungs, intestine, stomach, or any number of other organs or tissues. It can also be appreciated that some of these types of organs or tissues, including the heart for example, may have one or more internal tissue surfaces capable of being engaged by an apparatus of the present disclosure. For example, a user of such an apparatus may use the apparatus to engage the septum of the heart dividing one side of the heart from another. Such use may facilitate the delivery of a gas, liquid, and/or particulate(s) Co a particular side of the heart, as such a targeted delivery may provide beneficial effects, including, but not limited to, the ability to deliver a lead to pace the inner wall of the side of the heart. 
     Referring now to  FIGS. 20A, 20B, and 20C , embodiments of a portion of an apparatus for engaging a tissue according to the present disclosure are shown. As shown in  FIG. 20A , an exemplary embodiment of a portion of an apparatus for engaging a tissue comprises sleeve  1800  slidingly engaging engagement catheter  1810 , and when sleeve  1800  is slid in the direction of the arrow shown, skirt  1830  is revealed, having an expanded, optionally frusto-conical configuration as shown. Delivery catheter  1840  may exit out of a delivery lumen (not shown), with needle  1890  present at the distal end of delivery catheter  1840 . As shown in the embodiment of  FIG. 20A , lead  1900  is present, exiting out of an aperture of needle  1890 ,  FIGS. 20B and 20C  show a closer view of an embodiment of a portion of an apparatus for engaging a tissue according to the present disclosure than is shown in  FIG. 20A . As shown in  FIGS. 20B and 20C , aperture  1920  of needle  1890  is shown, and as shown in  FIG. 20C , lead  1900  may exit aperture  1920  of needle  1890 . 
     Referring now to  FIGS. 5A, 5B, 5C, and 5D , there is shown another embodiment of an engagement catheter as disclosed herein. Engagement catheter  700  is an elongated tube having a proximal end  710  and a distal end  720 , as well as two lumens  730 ,  740  extending between proximal end  710  and distal end  720 . Lumens  730 ,  740  are formed by concentric inner wall  750  and outer wall  760 , as particularly shown in  FIGS. 5B and 5C . At proximal end  710 , engagement catheter  700  includes a vacuum port  770 , which is attached to lumen  730  so that a vacuum source can be attached to vacuum port  770  to create suction in lumen  730 , thereby forming a suction channel. At distal end  720  of catheter  700 , a suction port  780  is attached to lumen  730  so that suction port  780  can be placed in contact with heart tissue  775  (see  FIG. 5D ) for aspirating the tissue, thereby forming a vacuum seal between suction port  780  and tissue  775  when the vacuum source is attached and engaged. The vacuum seal enables suction port  780  to grip, stabilize, and retract tissue  775 . For example, attaching a suction port to an interior atrial wall using a vacuum source enables the suction port to retract the atrial wall from the pericardial sac surrounding the heart, which enlarges the pericardial space between the atrial wall and the pericardial sac. 
     As shown in  FIG. 5C , two internal lumen supports  810 ,  820  are located within lumen  730  and are attached to inner wall  750  and outer wall  760  to provide support to the walls. These lumen supports divide lumen  730  into two suction channels. Although internal lumen supports  810 ,  820  extend from distal end  720  of catheter  700  along a substantial portion of the length of catheter  700 , internal lumen supports  810 ,  820  may or may not span the entire length of catheter  700 . Indeed, as shown in  FIGS. 5A, 5B, and 5C , internal lumen supports  810 ,  820  do not extend to proximal end  710  to ensure that the suction from the external vacuum source is distributed relatively evenly around the circumference of catheter  700 . Although the embodiment shown in  FIG. 5C  includes two internal lumen supports, other embodiments may have just one internal support or even three or more such supports. 
       FIG. 5D  shows engagement catheter  700  approaching heart tissue  775  for attachment thereto. It is important for the clinician performing the procedure to know when the suction port has engaged the tissue of the atrial wall or the atrial appendage. For example, in reference to  FIG. 5D , it is clear that suction port  780  has not fully engaged tissue  775  such that a seal is formed. However, because suction port  780  is not usually seen during the procedure, the clinician may determine when the proper vacuum seal between the atrial tissue and the suction port has been made by monitoring the amount of blood that is aspirated, by monitoring the suction pressure with a pressure sensor/regulator, or both. For example, as engagement catheter  700  approaches the atrial wall tissue (such as tissue  775 ) and is approximately in position, the suction can be activated through lumen  730 . A certain level of suction (e.g., 10 mmHg) can be imposed and measured with a pressure sensor/regulator. As long as catheter  700  does not engage the wall, some blood will be aspirated into the catheter and the suction pressure will remain the same. However, when catheter  700  engages or attaches to the wall of the heart (depicted as tissue  775  in  FIG. 5D ), minimal blood is aspirated and the suction pressure will start to gradually increase. Each of these signs can alert the clinician (through alarm or other means) as an indication of engagement. The pressure regulator is then able to maintain the suction pressure at a preset value to prevent over-suction of the tissue. 
     An engagement catheter, such as engagement catheter  700 , may be configured to deliver a fluid or other substance to tissue on the inside of a wall of the heart, including an atrial wall or a ventricle wall. For example, lumen  740  shown in  FIGS. 5A and 5C  includes an injection channel  790  at distal end  720 . Injection channel  790  dispenses to the targeted tissue a substance flowing through lumen  740 . As shown in  FIG. 5D , injection channel  790  is the distal end of lumen  740 . However, in other embodiments, the injection channel may be ring-shaped (see  FIG. 2C ) or have some other suitable configuration. 
     Substances that can be locally administered with an engagement catheter include preparations for gene or cell therapy, drugs, and adhesives that are safe for use in the heart. The proximal end of lumen  740  has a fluid port  800 , which is capable of attachment to an external fluid source for supply of the fluid to be delivered to the targeted tissue. Indeed, after withdrawal of a needle from the targeted tissue, as discussed herein, an adhesive may be administered to the targeted tissue by the engagement catheter for sealing the puncture wound left by the needle withdrawn from the targeted tissue. 
     Referring now to  FIGS. 6A, 6B, and 6C , there is shown a delivery catheter  850  comprising an elongated hollow tube  880  having a proximal end  860 , a distal end  870 , and a lumen  885  along the length of the catheter. Extending from distal end  870  is a hollow needle  890  in communication with lumen  885 . Needle  890  is attached to distal end  870  in the embodiment of  FIGS. 6A, 6B, and 6C , hut, in other embodiments, the needle may be removably attached to, or otherwise located at, the distal end of the catheter (see  FIG. 1A ). In the embodiment shown in  FIGS. 6A, 6B, and 6C , as in certain other embodiments having an attached needle, the junction (i.e., site of attachment) between hollow tube  880  and needle  890  forms a security notch  910  circumferentially around needle  890  to prevent needle  890  from over-perforation. Thus, when a clinician inserts needle  890  through an atrial wall to gain access to the pericardial space, the clinician will not, under normal conditions, unintentionally perforate the pericardial sac with needle  890  because the larger diameter of hollow tube  880  (as compared to that of needle  890 ) at security notch  910  hinders further needle insertion. Although security notch  910  is formed by the junction of hollow tube  880  and needle  890  in the embodiment shown in  FIGS. 6A, 6B, and 6C , other embodiments may have a security notch that is configured differently. For example, a security notch may include a band, ring, or similar device that is attached to the needle a suitable distance from the tip of the needle. Like security notch  910 , other security notch embodiments hinder insertion of the needle past the notch itself by presenting a larger profile than the profile of the needle such that the notch does not easily enter the hole in the tissue caused by entry of the needle. 
     It is useful for the clinician performing the procedure to know when the needle has punctured the atrial tissue. This can be done in several ways. For example, the delivery catheter can be connected to a pressure transducer to measure pressure at the tip of the needle. Because the pressure is lower and much less pulsatile in the pericardial space than in the atrium, the clinician can recognize immediately when the needle passes through the atrial tissue into the pericardial space. 
     Alternatively, as shown in  FIG. 6B , needle  890  may be connected to a strain gauge  915  as part of the catheter assembly. When needle  890  contacts tissue (not shown), needle  890  will be deformed. The deformation will be transmitted to strain gauge  915  and an electrical signal will reflect the deformation (through a classical wheatstone bridge), thereby alerting the clinician. Such confirmation of the puncture of the wall can prevent over-puncture and can provide additional control of the procedure. 
     In some embodiments, a delivery catheter, such as catheter  850  shown in  FIGS. 6A, 6B , and  6 C, is used with an engagement catheter, such as catheter  700  shown in  FIGS. 5A, 5B, 5C , and  5 D, to gain access to the pericardial space between the heart wall and the pericardial sac. For example, engagement catheter  700  may be inserted into the vascular system and advanced such that the distal end of the engagement catheter is within the atrium. The engagement catheter may be attached to the targeted tissue on the interior of a wall of the atrium using a suction port as disclosed herein. A standard guide wire may be inserted through the lumen of the delivery catheter as the delivery catheter is inserted through the inner lumen of the engagement catheter, such as lumen  740  shown in  FIGS. 5B and 5C . Use of the guide wire enables more effective navigation of the delivery catheter  850  and prevents the needle  890  from damaging the inner wall  750  of the engagement catheter  700 . When the tip of the delivery catheter with the protruding guide wire reaches the atrium, the wire is pulled back, and the needle is pushed forward to perforate the targeted tissue. The guide wire is then advanced through the perforation into the pericardial space, providing access to the pericardial space through the atrial wall. 
     Referring again to  FIGS. 6A, 6B, and 6C , lumen  885  of delivery catheter  850  may be used for delivering fluid into the pericardial space after needle  890  is inserted through the atrial wall or the atrial appendage. After puncture of the wall or appendage, a guide wire (not shown) may be inserted through needle lumen  900  into the pericardial space to maintain access through the atrial wall or appendage. Fluid may then be introduced to the pericardial space in a number of ways. For example, after the needle punctures the atrial wall or appendage, the needle is generally withdrawn. If the needle is permanently attached to the delivery catheter, as in the embodiment shown in  FIGS. 6A and 6B , then delivery catheter  850  would be withdrawn and another delivery catheter (without an attached needle) would be introduced over the guide wire into the pericardial space. Fluid may then be introduced into the pericardial space through the lumen of the second delivery catheter. 
     In some embodiments, however, only a single delivery catheter is used. In such embodiments, the needle is not attached to the delivery catheter, but instead may be a needle wire (see  FIG. 1A ). In such embodiments, the needle is withdrawn through the lumen of the delivery catheter, and the delivery catheter may be inserted over the guide wire into the pericardial space. Fluid is then introduced into the pericardial space through the lumen of the delivery catheter. 
     The various embodiments disclosed herein may be used by clinicians, for example: (1) to deliver genes, cells, drugs, etc.; (2) to provide catheter access for epicardial stimulation; (3) to evacuate fluids acutely (e.g., in cases of pericardial tampondae) or chronically (e.g., to alleviate effusion caused by chronic renal disease, cancer, etc.); (4) to perform transeptal puncture and delivery of a catheter through the left atrial appendage for electrophysiological therapy, biopsy, etc.; (5) to deliver a magnetic glue or ring through the right atrial appendage to the aortic root to hold a percutaneous aortic valve in place: (6) to deliver a catheter for tissue ablation, e.g., to the pulmonary veins, or right atrial and epicardial surface of the heart for atrial and ventricular arrythmias; (7) to deliver and place epicardial, right atrial, and right and left ventricle pacing leads (as discussed herein); (8) to occlude the left atrial appendage through percutaneous approach; and (9) to visualize the pericardial space with endo-camera or scope to navigate the epicardial surface of the heart for therapeutic delivery, diagnosis, lead placement, mapping, etc. Many other applications, not explicitly listed here, are also possible and within the scope of the present disclosure. 
     Referring now to  FIG. 7 , there is shown a delivery catheter  1000 . Delivery catheter  1000  includes an elongated tube  1010  having a wall  1020  extending from a proximal end (not shown) of tube  1010  to a distal end  1025  of tube  1010 . Tube  1010  includes two lumens, but other embodiments of delivery catheters may have fewer than, or more than, two lumens, depending on the intended use of the delivery catheter. Tube  1010  also includes a steering channel  1030 , in which a portion of steering wire system  1040  is located. Steering channel  1030  forms orifice  1044  at distal end  1025  of tube  1010  and is sized to fit over a guide wire  1050 . 
       FIG. 8  shows in more detail steering wire system  1040  within steering channel  1030  (which is shown cut away from the remainder of the delivery catheter). Steering wire system  1040  is partially located in steering channel  1030  and comprises two steering wires  1060  and  1070  and a controller  1080 , which, in the embodiment shown in  FIG. 8 , comprises a first handle  1090  and a second handle  1094 . First handle  1090  is attached to proximal end  1064  of steering wire  1060 , and second handle  1094  is attached to proximal end  1074  of steering wire  1070 . Distal end  1066  of steering wire  1060  is attached to the wall of the tube of the delivery catheter within steering channel  1030  at attachment  1100 , and distal end  1076  of steering wire  1070  is attached to the wall of the tube of the delivery catheter within steering channel  1030  at attachment  1110 . As shown in  FIG. 7 , attachment  1100  and attachment  1110  are located on opposing sides of steering channel  1030  near distal tip  1120  of delivery catheter  1000 . 
     In the embodiment of  FIG. 8 , steering wires  1060  and  1070  are threaded as a group through steering channel  1030 . However, the steering wire systems of other embodiments may include steering wires that are individually threaded through smaller lumens within the steering channel. For example,  FIG. 11  shows a cross-sectional view of a delivery catheter  1260  having an elongated tube  1264  comprising a wall  1266 , a steering channel  1290 , a first lumen.  1270 , and a second lumen  1280 . Delivery catheter  1260  further includes a steering wire  1292  within a steering wire lumen  1293 , a steering wire  1294  within a steering wire lumen  1295 , and a steering wire  1296  within a steering wire lumen  1297 . Each of steering wire lumens  1293 ,  1295 , and  1297  is located within steering channel  1290  and is formed from wall  1266 . Each of steering wires  1292 ,  1294 , and  1296  is attached to wall  1266  within steering channel  1290 . As will be explained, the attachment of each steering wire to the wall may be located near the distal tip of the delivery catheter, or may be located closer to the middle of the delivery catheter. 
     Referring now to  FIGS. 7 and 8 , steering wire system  1040  can be used to control distal tip  1120  of delivery catheter  1000 . For example, when first handle  1090  is pulled, steering wire  1060  pulls distal tip  1120 , which bends delivery catheter  1000 , causing tip deflection in a first direction. Similarly, when second handle  1094  is pulled, steering wire  1070  pulls distal tip  1120  in the opposite direction, which bends delivery catheter  1000 , causing tip deflection in the opposite direction. Thus, delivery catheter  1000  can be directed (i.e., steered) through the body using steering wire system  1040 . 
     Although steering wire system  1040  has only two steering wires, other embodiments of steering wire systems may have more than two steering wires. For example, some embodiments of steering wire systems may have three steering wires (see  FIG. 11 ), each of which is attached to the steering channel at a different attachment. Other embodiments of steering wire systems may have four steering wires. Generally, more steering wires give the clinician more control for directing the delivery catheter because each additional steering wire enables the user to deflect the tip of the delivery catheter in an additional direction. For example, four steering wires could be used to direct the delivery catheter in four different directions (e.g., up, down, right, and left). 
     If a steering wire system includes more than two steering wires, the delivery catheter may be deflected at different points in the same direction. For instance, a delivery catheter with three steering wires may include two steering wires for deflection in a certain direction and a third steering wire for reverse deflection (i.e., deflection in the opposite direction). In such an embodiment, the two steering wires for deflection are attached at different locations along the length of the delivery catheter. Referring now to  FIGS. 9A-9C , there is shown a steering wire system  1350  within steering channel  1360  (which is shown cut away from the remainder of the delivery catheter) in different states of deflection. Steering wire system  1350  is partially located in steering channel  1360  and comprises three steering wires  1370 ,  1380 , and  1390  and a controller  1400 , which, in the embodiment shown in  FIGS. 9A-9C , comprises a handle  1410 . Handle  1410  is attached to proximal end  1374  of steering wire  1370 , proximal end  1384  of steering wire  1380 , and proximal end  1394  of steering wire  1390 . Distal end  1376  of steering wire  1370  is attached to the wall of the tube of the delivery catheter within steering channel  1360  at attachment  1378 , which is near the distal tip of the delivery catheter (not shown). Distal end  1386  of steering wire  1380  is attached to the wall of the tube of the delivery catheter within steering channel  1360  at attachment  1388 , which is near the distal tip of the delivery catheter (not shown). Attachment  1378  and attachment  1388  are located on opposing sides of steering channel  1360  such that steering wires  1370  and  1380 , when tightened (as explained below), would tend to deflect the delivery catheter in opposite directions. Distal end  1396  of steering wire  1390  is attached to the wall of the tube of the delivery catheter within steering channel  1360  at attachment  1398 , which is located on the delivery catheter at a point closer to the proximal end of the delivery catheter than attachments  1378  and  1388 . Attachment  1398  is located on the same side of steering channel  1360  as attachment  1388 , such that steering wires  1380  and  1390 , when tightened (as explained below), would tend to deflect the delivery catheter in the same direction. However, because attachment  1398  is closer to the proximal end of the delivery catheter than is attachment  1388 , the tightening of steering wire  1390  tends to deflect the delivery catheter at a point closer to the proximal end of the delivery catheter than does the tightening of steering wire  1380 . Thus, as shown in  FIG. 9A , the tightening of steering wire  1390  causes a deflection in the delivery catheter approximately at point  1410 . The tightening of steering wire  1380  at the same time causes a further deflection in the delivery catheter approximately at point  1420 , as shown in  FIG. 9B . The tightening of steering wire  1370 , therefore, causes a reverse deflection, returning the delivery catheter to its original position (see  FIG. 9C ). 
     Referring again to  FIG. 7 , elongated tube  1010  further includes lumen  1130  and lumen  1140 . Lumen  1130  extends from approximately the proximal end (not shown) of tube  1010  to or near distal end  1025  of tube  1010 . Lumen  1130  has a bend  1134 , relative to tube  1010 , at or near distal end  1025  of tube  1010  and an outlet  1136  through wall  1020  of tube  1010  at or near distal end  1025  of tube  1010 . Similarly, lumen  1140  has a bend  1144 , relative to tube  1010 , at or near distal end  1025  of tube  1010  and an outlet  1146  through wall  1020  of tube  1010  at or near distal end  1025  of tube  1010 . In the embodiment shown in  FIG. 7 , lumen  1130  is configured as a laser Doppler tip, and lumen  1140  is sized to accept a retractable sensing lead  1150  and a pacing lead  1160  having a tip at the distal end of the lead. The fiberoptic laser Doppler tip detects and measures blood flow (by measuring the change in wavelength of Hat emitted by the tip), which helps the clinician to identify—and then avoid—blood vessels during lead placement. Sensing lead  1150  is designed to detect electrical signals in the heart tissue so that the clinician can avoid placing a pacing lead into electrically nonresponsive tissue, such as scar tissue. Pacing lead  1160  is a screw-type lead for placement onto the cardiac tissue, and its tip, which is an electrode, has a substantially screw-like shape. Pacing lead  1160  is capable of operative attachment to a CRT device (not shown) for heart pacing. Although lead  1160  is used for cardiac pacing, any suitable types of leads may be used with the delivery catheters described herein, including sensing leads. 
     Each of bend  1134  of lumen  1130  and bend  1144  of lumen  1140  forms an approximately 90-degree angle, which allows respective outlets  1136  and  1146  to face the external surface of the heart as the catheter is maneuvered in the pericardial space. However, other embodiments may have bends forming other angles, smaller or larger than 90-degrees, so long as the lumen provides proper access to the external surface of the heart from the pericardial space. Such angles may range, for example, from about 25-degrees to about 155-degrees. In addition to delivering leads and Doppler tips, lumen  1130  and lumen  1140  may be configured to allow, for example, the taking of a cardiac biopsy, the delivery of gene cell treatment or pharmacological agents, the delivery of biological glue for ventricular reinforcement, implementation of ventricular epicardial suction in the acute myocardial infarction and border zone area, the removal of fluid in treatment of pericardial effusion or cardiac tamponade, or the ablation of cardiac tissue in treatment of atrial fibrillation. 
     For example, lumen  1130  could be used to deliver a catheter needle for intramyocardial injection of gene cells, stems, biomaterials, growth factors (such as cytokinase, fibroblast growth factor, or vascular endothelial growth factor) and/or biodegradable synthetic polymers, RGD-liposome biologic glue, or any other suitable drug or substance for treatment or diagnosis. For example, suitable biodegradable synthetic polymer may include polylactides, polyglycolides, polycaprolactones, polyanhydrides, polyamides, and polyurethanes. In certain embodiments, the substance comprises a tissue inhibitor, such as a metalloproteinase (e.g., metalloproteinase  1 ). 
     The injection of certain substances (such as biopolymers and RGD-liposome biologic glue) is useful in the treatment of chronic heart failure to reinforce and strengthen the left ventricular wall. Thus, using the embodiments disclosed herein, the injection of such substances into the cardiac tissue from the pericardial space alleviates the problems and risks associated with delivery via the transthoracic approach. For instance, once the distal end of the delivery catheter is advanced to the pericardial space, as disclosed herein, a needle is extended through a lumen of the delivery catheter into the cardiac tissue and the substance is injected through the needle into the cardiac tissue. 
     The delivery of substances into the cardiac tissue from the pericardial space can be facilitated using a laser Doppler tip. For example, when treating ventricular wall thinning, the laser Doppler tip located in lumen  1140  of the embodiment shown in  FIG. 7  can be used to measure the thickness of the left ventricular wall during the procedure (in real time) to determine the appropriate target area for injection. 
     Referring again to  FIG. 8 , although controller  1080  comprises first handle  1090  and second handle  1094 , other embodiments of the controller may include different configurations. For example, instead of using handles, a controller may include any suitable torque system for controlling the steering wires of the steering wire system. Referring now to  FIG. 10 , there is shown a portion of a steering wire system  1170  having steering wire  1180 , steering wire  1190 , and controller  1200 . Controller  1200  comprises a torque system  1210  having a first rotatable spool  1220 , which is capable of collecting and dispensing steering wire  1180  upon rotation. For example, when first rotatable spool  1220  rotates in a certain direction, steering wire  1180  is collected onto spool  1220 , thereby tightening steering wire  1180 . When spool  1220  rotates in the opposite direction, steering wire  1180  is dispensed from spool  1220 , thereby loosening steering wire  1180 . Torque system  1210  also has a second rotatable spool  1230 , which is capable of collecting and dispensing steering wire  1190  upon rotation, as described above. 
     Torque system  1210  further includes a first rotatable dial  1240  and a second rotatable dial  1250 . First rotatable dial  1240  is attached to first rotatable spool  1220  such that rotation of first rotatable dial  1240  causes rotation of first rotatable spool  1220 . Similarly, second rotatable dial  1250  is attached to second rotatable spool  1230  such that rotation of second rotatable dial  1250  causes rotation of second rotatable spool  1230 . For ease of manipulation of the catheter, torque system  1210 , and specifically first and second rotatable dials  1240  and  1250 , may optionally be positioned on a catheter handle (not shown) at the proximal end of tube  1010 . 
     Steering wire system  1170  can be used to direct a delivery catheter through the body in a similar fashion as steering wire system  1140 . Thus, for example, when first rotatable dial  1240  is rotated in a first direction (e.g., clockwise), steering wire  1180  is tightened and the delivery catheter is deflected in a certain direction. When first rotatable dial  1240  is rotated in the other direction (e.g., counterclockwise), steering wire  1180  is loosened and the delivery catheter straightens to its original position. When second rotatable dial  1250  is rotated in one direction (e.g., counterclockwise), steering wire  1190  is tightened and the delivery catheter is deflected in a direction opposite of the first deflection. When second rotatable dial  1250  is rotated in the other direction (e.g., clockwise), steering wire  1190  is loosened and the delivery catheter is straightened to its original position. 
     Certain other embodiments of steering wire system may comprise other types of torque system, so long as the torque system permits the clinician to reliably tighten and loosen the various steering wires. The magnitude of tightening and loosening of each steering wire should be controllable by the torque system. 
     Referring again to  FIG. 11 , there is shown a cross-sectional view of delivery catheter  1260 . Delivery catheter  1260  includes tube  1265 , a first lumen  1270 , a second lumen  1280 , and a steering channel  1290 . Steering wires  1292 ,  1294 , and  1296  are shown within steering channel  1290 . First lumen  1270  has outlet  1275 , which can be used to deliver a micro-camera system (not shown) or a laser Doppler tip  1278 . Second lumen  1280  is sized to deliver a pacing lead  1300 , as well as a sensing lead (not shown). 
     Treatment of cardiac tamponade, by the removal of a pericardial effusion, may be accomplished using an apparatus of the present disclosure as described below. A typical procedure would involve the percutaneous intravascular insertion of a portion of an apparatus into a body, which can be performed under local or general anesthesia. A portion of the apparatus may then utilize an approach described herein or otherwise known by a user of the apparatus to enter the percutaneous intravascular pericardial sac. It can be appreciated that such an apparatus may be used to access other spaces within a body to remove fluid and/or deliver a gas, liquid, and/or particulate(s) as described herein, and that such an apparatus is not limited to heart access and removal of pericardial effusions. 
     Exemplary embodiments of a portion of such an apparatus are shown in  FIGS. 21A and 21B . As shown in  FIG. 21A , a perforated drainage catheter  2100  is provided. Perforated drainage catheter  2100  comprises a tube defining at least one suction/injection aperture  2110 , and as shown in the embodiment in  FIG. 21A , perforated drainage catheter  2100  defines multiple suction/injection apertures  2110 . Suction/injection apertures  2110  are operably connected to an internal lumen defined within perforated delivery catheter  2100 . It can be appreciated that the portion of perforated drainage catheter  2100  as shown in  FIGS. 21A and 21B  may be coupled to one or more portions of a system for engaging a tissue as described herein. As such, one or more portions of a system for engaging a tissue may be used to define a system for removing fluid as described herein. 
     It can be appreciated that the internal lumen within perforated delivery catheter  2100  may define multiple internal channels. For example, perforated delivery catheter  2100  may define two channels, one channel operably coupled to one or more suction/injection apertures  2110  to allow for a vacuum source coupled to one end of the channel to provide suction via the suction/injection apertures  2110 , and one channel operably coupled to one or more other suction/injection channels to allow for the injection of gas, liquid, and/or particulate(s) to a target site. 
     As described in further detail below, when perforated drainage catheter  2100  enters a space in a body, for example a pericardial sac, perforated drainage catheter  2100  may be used to remove fluid by the use of suction through one or more suction/injection apertures  2110 , Perforated drainage catheter  2100  may also be used to deliver gas, liquid, and/or particulate(s) to a target site through one or more suction/injection apertures  2110 . 
     Another exemplary embodiment of a portion of a perforated drainage catheter  2100  is shown in  FIG. 21B . As shown in  FIG. 21B , perforated drainage catheter  2100  comprises a tube with multiple suction/injection apertures  2110 . However, in this exemplary embodiment, perforated drainage catheter  2100  comprises a number of concave grooves  2120  extending a portion of a length of perforated drainage catheter  2100 , whereby the suction/injection apertures  2110  are provided at the recessed portions therein. Concave grooves  2120 , when positioned at least partially around the circumference of perforated drainage catheter  2100 , define one or more ridges  2130  extending a portion of a length of perforated drainage catheter  2100 . Said ridges  2130  of perforated drainage catheter  2100 , when positioned at or near a tissue (not shown), aid to prevent a tissue from coming in direct contact with one or more suction/injection apertures  2110 . For example, when perforated drainage catheter  2100  is used in a manner described herein and when a vacuum is coupled to perforated drainage catheter  2100 , suction from one or more suction/injection apertures  2110  positioned within one or more concave grooves  2120  would allow for the removal of fluid present in the area of perforated drainage catheter  2100 . Ridges  2130  would aid to prevent or minimize tissue adhesion and/or contact with the one or more suction/injection apertures  2110 . 
     A procedure using perforated drainage catheter  2100  may be performed by inserting perforated drainage catheter  2100  into a pericardial sac, following the cardiac surface using, for example, fluoroscopy and/or echodoppler visualization techniques. When perforated drainage catheter  2100  is inserted into a pericardial sac, a pericardial effusion present within the pericardial sac, may be removed by, for example, gentle suction using a syringe. In one example, a 60 cc syringe may be used to remove the effusion with manual gentle suction. When the effusion has been removed, the patients hemodynamic parameters may be monitored to determine the effectiveness of the removal of the effusion. When the pericardial sac is empty, determined by, for example, fluoroscopy or echodoppler visualization, the acute pericardial effusion catheter may be removed, or it may be used for local treatment to introduce, for example, an antibiotic, chemotherapy, or another drug as described below. 
     An exemplary embodiment of a portion of a perforated drainage catheter  2100  present within a pericardial sac is shown in  FIG. 22 . As shown in  FIG. 22 , perforated drainage catheter  2100  is first inserted into the heart  2200  using one or more of the techniques and/or procedures described herein, and is placed through the right atrial appendage  2210 , the visceral pericardium  2215 , and into the pericardial sac  2220 . The outer portion of the pericardial sac  2220  is defined by the parietal pericardium  2230 . A pericardial effusion  2240  (fluid within the pericardial sac  2220 ) may then be removed using perforated drainage catheter  2100 . When a vacuum source (not shown) is coupled to the proximal end of a portion of a system for removing fluid (comprising, in part, perforated drainage catheter  2100  and one or more other components of a system for engaging a tissue as described herein), the introduction of a vacuum to perforated drainage catheter  2100  allows the pericardial effusion  2240  (the fluid) to be withdrawn from the pericardial sac  2220  into one or more suction/injection apertures  2110  defined along a length of suction/injection apertures  2110 . 
     When perforated drainage catheter  2100  is used to remove some or all of a pericardial effusion (or other fluid present within a space within a body), it may also be used to deliver a gas, liquid, and/or particulate(s) at or near the space where the fluid was removed. For example, the use of perforated drainage catheter  2100  to remove a pericardial effusion may increase the risk of infection. As such, perforated drainage catheter  2100  may be used to rinse the pericardial sac (or other space present within a body) with water and/or any number of beneficial solutions, and may also be used to deliver one or more antibiotics to provide an effective systemic antibiotic therapy for the patient. While the intrapericardial instillation of antibiotics (e.g., gentamycin) is useful, it is typically not sufficient by itself, and as such, it may be combined with general antibiotics treatment for a more effective treatment. 
     An exemplary embodiment of a steering engagement catheter of the disclosure of the present application is shown in  FIG. 23 . As shown in  FIG. 23 , steering engagement catheter  2300  comprises an elongated tube  2302  having a proximal end  2304  and a distal end  2306 , the elongated tube  2302  comprising a first wall  2308  positioned circumferentially along the length of elongated tube  2302 . Steering engagement catheter  2300  further comprises at least one steering wire  2310 , wherein steering wire  2310  has a proximal end  2312  and a distal end  2314 . The distal end  2314  of steering wire  2310  may coupled to the first wall  2308  of the elongated tube  2302  at or near the distal end  2306  of the elongated tube  2302 . It can be appreciated that the distal end  2314  of steering wire  2310  may be coupled to other portions of steering engagement catheter  2300  and continue to be operable as referenced herein. It can further be appreciated that more than one steering wire  2310  may be positioned relative to steering engagement catheter  2300  and operate the same or similar to other steering wire(s)  2310  of engagement catheter  2300 . 
     To operate the steering wire  2310 , steering engagement catheter  2300  further comprises a controller  2316  operably coupled to at least one steering wire  2310  at or near the proximal end  2312  of the steering wire  2310 . Controller  2316  may be positioned along the elongated tube  2302  at or near the proximal end  2304  of the elongated tube  2302 . 
     As the distal end  2314  of steering wire  2310  is coupled to first wall  2308  (or another portion of steering engagement catheter  2300 ) and the proximal end  2312  of steering wire  2310  is coupled to controller  2316 , operation of controller  2316  causes the elongated tube  2302  to bend in response to movement of the steering wire  2310 . If one or more anchor positions  2318  are present along elongated tube  2302 , steering wire(s)  2310  may slidingly engage the elongated tube  2302  at said anchor positions  2318  along the elongated tube  2302 . As such, operation of controller  2316  may causes the steering wire(s)  2310  to slide along the anchor position(s)  2318 , causing the elongated tube  2302  to bend in response to movement of the steering wire(s)  2310 . 
     A steering engagement catheter  2300  of the disclosure of the present application may be straight, substantially straight, curved, or of another configuration useful in accordance with the present application. In at least one embodiment, the bend of the elongated tube  2302 , as referenced above, bends an otherwise substantially straight elongated tube  2302 , In another embodiment, the bend of the elongated tube  2302  further bends an otherwise bent elongated tube  2302 . 
     In an embodiment of steering engagement catheter  2300  of the present disclosure, steering engagement catheter  2300  comprises two or more anchor positions  2318 , and operation of the controller  2316  causes steering wire(s)  2310  to slide along the two or more anchor positions  2318  causing the elongated tube  2302  to bend in two or more places in response to movement of steering wire(s)  2310 . In at least one embodiment of steering engagement catheter  2300 , operation of the controller  2316  in a first direction causes steering wire(s)  2310  to slide along the anchor positions  2318  in a direction toward the controller  2316 , causing the elongated tube  2302  to bend in a first direction. Furthermore, and in the same or another embodiment, operation of the controller  2316  in a second direction causes steering wire(s)  2310  to slide along the anchor positions  2318  in a direction away from the controller  2316 , causing the elongated tube  2302  to straighten at least partially from an initially bent configuration. 
     In at least one embodiment, steering engagement catheter  2300  comprises two steering wires  2310 , wherein the two steering wires  2310  slidingly engage the elongated tube  2302  at two or more anchor positions  2318 . In the same or another embodiment, the two or more anchor positions  2318  comprise four anchor positions  2318 , wherein one of the two steering wires  2310  slidingly engages the elongated tube  2302  at two of the four anchor positions  2318 , and wherein the other steering wire  2310  slidingly engages the elongated tube  2302  at the other two of the four anchor positions  2318 . In such an embodiment, operation of the controller  2316  causes the two steering wires  2310  to slide along the four anchor positions  2316 , causing the elongated tube  2202  to bend in two places in response to movement of the two steering wires  2310 . 
     In at least one embodiment of a steering engagement catheter of the present application, the controller  2316  optionally comprises a handle  2320  coupled to the steering wire(s)  2310  at or near the proximal end(s)  2312  of the steering wire(s). In an embodiment comprising two steering wires  2310 , controller  2316  may comprise a first handle  2320  coupled to one of the two steering wires  2310  at or near the proximal end  2312  of that steering wire  2310 , and the controller  2316  may comprise a second handle  2320  coupled to the other of the two steering wires  2310  at or near the proximal end  2312  of the other of the two steering wires  2310 . 
     Steering engagement catheter  2300 , controller  2316  may comprise a rotatable spool  2322  (as shown in  FIGS. 24, 25A, and 25B ) coupled to the steering wire(s)  2310  at or near the proximal end(s)  2312  of the steering wire(s)  2310 , whereby the rotatable spool  2322  may operate to collect and dispense the steering wire(s)  2310 . In another embodiment, the rotatable spool  2322  is coupled to a rotatable dial  2324  (as shown in  FIGS. 24, 25A, and 25B ), so that rotation of the rotatable dial  2324  causes rotation of the rotatable spool  2322 , wherein the rotation of the rotatable spool  2322  causes the elongated tube  2302  to bend in response to movement of the steering wine(s)  2310 . 
     In additional embodiments of a steering engagement catheter  2300  of the present application, steering engagement catheter  2300  may comprise multiple steering wires  2310 , multiple rotatable spools  2322 , multiple rotatable dials  2324 , wherein operation of said components of steering engagement catheter  2300  causes the elongated tube  2302  to bend and/or straighten. As shown in the exemplary embodiments of  FIGS. 25A and 25B , for example, operation of rotatable spool  2322  and/or rotatable dial  2324  may facilitate the bending of steering engagement catheter  2300  (as shown in  FIG. 25B ) at anchor points  2318  from an originally straight steering engagement catheter  2300  (as shown in  FIG. 25A ). 
     In at least one embodiment, steering engagement catheter  2300  further comprises a skirt  2326  operatively connected to the distal end  2306  of the elongated tube  2302 . Referring to  FIG. 23 , skirt  2326  may comprise a proximal end  2328  having a circumference substantially similar to an outer circumference of the elongated tube  2302 , and skirt  2326  may further comprise a distal end  2330  having a circumference larger than the circumference of the elongated tube  2302 . Skirt  2326  may be operable to engage a larger surface area of a tissue, for example, than a steering engagement catheter  2300  without a skirt  2326  would be able to engage, providing, for example, increased suction as described herein. Skirt  2326  may have one or more of the same configurations or uses as described herein and within  FIGS. 16A-20C . 
     In at least one embodiment of a steering engagement catheter  2300  of the disclosure of the present application, the elongated tube  2302  may further comprise a second wall  2332  positioned circumferentially along the length of the elongated tube  2302 , wherein the first wall  2308  and the second wall  2332  form at least one suction channel  2334  (as shown in  FIG. 23 ) along the length of the elongated tube  2302  between the first wall  2308  and the second wall  2332 . Suction channel  2334  may define a vacuum port  2336  at the proximal end  2304  of elongated tube  2302  and may further define a suction port  2338  at the distal end  2306 , wherein the vacuum port  2336  may be operatively coupled to a vacuum source  2340  (as shown in  FIG. 24 ), and wherein the suction port  2338  is configured to engage a surface of a tissue. 
     In at least one embodiment, steering engagement catheter  2300  may further comprise a skirt  2326  coupled to the distal end  2306  of the elongated tube  2302  at or near the suction port  2338 , wherein the distal end  2330  of the skirt  2326  is operable to removably engage the surface of the tissue such that the skirt  2326  is capable of forming a reversible seal with the surface of the tissue when a vacuum source  2340  is operatively attached to the vacuum port  2336 . Skirt  2326 , as provided herein, may comprise a deformable configuration that may be capable of expanding one or more expanded configurations, noting that the expanded configurations may include, but are not limited to, a frusto-conical configuration or an irregular frusto-conical configuration. 
     In at least one embodiment, a sleeve  2342  may be positioned circumferentially around and slidingly engage the elongated tube  2302 . In such an embodiment, skirt  2326  may have a collapsed configuration when skirt  2326  is at least partially surrounded by the sleeve  2342 , and skirt  2326  may have an expanded configuration when it is not surrounded by the sleeve  2342 . Sleeve  2342  may have may have one or more of the same configurations or uses as described herein and within  FIGS. 16A-20C . Skirt  2326  may engage a tissue surrounding a heart, for example, to enlarge a pericardial space between the heart and a pericardial sac when the skirt  2326  is attached to an interior wall of the heart. 
     An exemplary steering engagement catheter  2300  of the disclosure of the present application may also comprise one or more internal lumen supports  2344  (as shown in  FIGS. 26C and 26D ) positioned within the suction channel  2334  and attached to the first wall  2308  and the second wall  2332 . Internal lumen support(s)  2344  may extend from the distal end  2306  of the elongated tube  2302  along at least a substantial portion of the length of the elongated tube  2302 . In an exemplary embodiment comprising two internal lumen supports  2344 , the two lumen supports  2344  may define a suction channel  2334  and an injection channel  2346  (as described below and herein). 
     In another exemplary embodiment, steering engagement catheter  2300  may further comprise an injection channel  2346  formed along the length of the elongated tube  2302 . Injection channel  2346  comprises an opening at its distal end administering a fluid to a tissue, wherein the injection channel  2346  is also capable of operable attachment to an external fluid source  2348  at the proximal end of the injection channel  2346 , such that fluid from the external fluid source  2348  can flow through the injection channel  2346  to the tissue when the external fluid source  2348  is operatively attached to the injection channel  2346 . 
       FIGS. 26A-26D  show cross-sectional views of at least a portion of exemplary embodiments of steering engagement catheters  2300  of the disclosure of the present application.  FIG. 26A  shows an exemplary embodiment of a steering engagement catheter  2300  comprising at least a first wall  2308  defining an internal lumen  2350 . Internal lumen  2350  may allow, for example, the entry of a delivery catheter as described herein.  FIG. 26B  shows an exemplary embodiment of a steering engagement catheter  2300  comprising at least a first wall  2308  and a second wall  2332 , whereby the first wall  2308  and the second wall  2332  defining an internal lumen  2350  and a suction channel  2334 . The use of two internal lumen supports  2344 , as shown in the exemplary embodiment of a steering engagement catheter  2300  in  FIG. 26C , further defines a third lumen, which, as shown in  FIG. 26C , may be an injection channel  2346 .  FIG. 26D  shows an exemplary embodiment of a steering engagement catheter  2300  comprising three internal lumen supports  2334 , with the first wall  2308 , second wall  2332 , and three internal lumen supports  2344  defining four lumens, namely internal lumen  2350 , suction channel  2334 , injection channel  2346 , and a fourth channel  2352 , which may be used as the various channels of the disclosure of the present application may allow or for any purpose consistent with the disclosure of the present application. 
     In at least one embodiment of a system comprising a steering engagement catheter  2300  of the disclosure of the present application, the system may also comprise a delivery catheter  2352  comprising a hollow tube having a proximal end and a distal end, wherein the delivery catheter configured such that the hollow tube is capable of insertion into a lumen of the steering engagement catheter. A needle located at the distal end of the delivery catheter to facilitate tissue puncture. Such a delivery catheter may be operable to deliver a substance to a target tissue, and may have one or more of the same configurations or uses as described herein with respect to delivery catheter  1840 , needle  1890 , and within  FIGS. 16A-17B, 19, and 20A-20C . 
     Furthermore, such an exemplary system may further comprise a guidewire capable of insertion through the delivery catheter into, for example, a periocardial space. A delivery catheter may also be useful to inject a fluid, including but not limited to an adhesive, to a target site within a body. Additional features and/or configurations of an exemplary delivery catheter and/or components of a system utilizing such a delivery catheter may include such features and/or configurations as otherwise provided herein. 
     In at least one embodiment of a system of the present disclosure, the system may comprise a steering engagement catheter, a delivery catheter, and a lead having a tip at its distal end and being configured for at least partial insertion into the first lumen of the delivery catheter. Such a lead may include one or more features and/or configurations as described herein with respect to lead  1900  and as shown in  FIGS. 19 and 20A-20C . 
     Use of a steering engagement catheter and/or a system comprising a steering engagement catheter is consistent with the operation of the same as provided herein. In one exemplary method for engaging a targeted tissue, the method comprises the steps of providing a steering engagement catheter and inserting the steering engagement catheter into a body such that the distal end of the steering engagement catheter is positioned at or near the targeted tissue. The insertion may be performed such that the distal end of the steering engagement catheter is positioned inside the heart and distal end of the steering engagement catheter is in contact with the targeted tissue on the interior of a wall of the heart. An additional step of operatively connecting a vacuum source to a lumen of the steering engagement catheter such that the distal end of the steering engagement catheter (or a skirt positioned thereto) is reversibly attached to the targeted tissue on the interior of a wall of the heart. 
     An exemplary method of using the aforementioned catheter and/or system may also comprise the step of operating a controller coupled to the steering engagement catheter to cause the elongated tube to bend in response to movement of a steering wire. An exemplary method may further comprises the steps of inserting the delivery catheter into a lumen of the steering engagement catheter, piercing the targeted tissue on the interior of a wall of the heart with a needle, administering a substance into the pericardial space, and/or withdrawing the needle from the targeted tissue and administering a substance to the targeted tissue after withdrawal of the needle. Exemplary methods may also comprise the steps of accessing the pericardial space by inserting a guide wire through the wall of the heart into the pericardial space, and operating the controller to cause the elongated tube to bend in response to movement of a steering wire. 
     An exemplary steering engagement catheter of the disclosure of the present application may be used to place a lead within a tissue of a heart. Such a method of use may comprise the steps of extending a steering engagement catheter into a blood vessel, aspirating a targeted tissue such that the wall of the heart is retracted away from a pericardial sac surrounding the heart to enlarge a pericardial space between the pericardial sac and the wall of the heart, accessing the pericardial space through the targeted tissue, inserting at least a distal end of a guide wire into the pericardial space, inserting into the first lumen of the elongated tube and over the guide wire a delivery catheter having at least one lumen, advancing at least the distal end of the delivery catheter through the targeted tissue into the pericardial space, directing the delivery catheter such that the outlet of the lumen of the delivery catheter is adjacent to the tissue of the heart, extending a lead through the lumen of the delivery catheter into the tissue of the heart, withdrawing the delivery catheter from the pericardial space, and withdrawing the guide wire from the pericardial space. An exemplary method of use may further comprise the step of extending a laser Doppler tip through a second lumen of the delivery catheter to the pericardial space, and using the controller to tighten at least one of the at least two steering wires. The method may also comprise the step of inserting into the targeted tissue over the guide wire a plug having a first end, a second end, and a hole extending from the first end to the second end, wherein the hole of the plug is self-sealing after removal of the guide wire. 
     Additional methods to treat neoplastic pericardial effusions without tamponade may be utilized using a device, system and/or method of the present disclosure. For example, a systemic antineoplastic treatment may be performed to introduce drugs to inhibit and/or prevent the development of tumors. If a non-emergency condition exists (e.g., not acardiac tamponade), a system and/or method of the present disclosure may be used to perform a pericardiocentesis. In addition, the present disclosure allows for the intrapericardial instillation of a cytostatic/sclerosing agent. It can be appreciated that using one or more of the devices, systems and/or methods disclosed herein, the prevention of recurrences may be achieved by intrapericardial instillation of sclerosing agents, cytotoxic agents, or immunomodulators, noting that the intrapericardial treatment may be tailored to the type of the tumor. Regarding chronic autoreactive pericardial effusions, the intrapericardial instillation of crystalloid glucacorticoids could avoid systemic side effects, while still allowing high local dose application. 
     A pacing lead may be placed on the external surface of the heart using an engagement catheter and a delivery catheter as disclosed herein. For example, an elongated tube of an engagement catheter is extended into a blood vessel so that the distal end of the tube is in contact with a targeted tissue on the interior of a wall of the heart. As explained above, the targeted tissue may be on the interior of the atrial wall or the atrial appendage. Suction is initiated to aspirate a portion of the targeted tissue to retract the cardiac wall away from the pericardial sac that surrounds the heart, thereby enlarging a pericardial space between the pericardial sac and the cardiac wall. A needle is then inserted through a lumen a the tube and advanced to the heart. The needle is inserted into the targeted tissue, causing a perforation of the targeted tissue. The distal end of a guide wire is inserted through the needle into the pericardial space to secure the point of entry through the cardiac wall. The needle is then withdrawn from the targeted tissue. 
     A delivery catheter, as described herein, is inserted into the lumen of the tube of the engagement catheter and over the guide wire. The delivery catheter may be a 14 Fr. radiopaque steering catheter. The distal end of the delivery catheter is advanced over the guide wire through the targeted tissue into the pericardial space. Once in the pericardial space, the delivery catheter is directed using a steering wire system as disclosed herein. In addition, a micro-camera system may be extended through the lumen of the delivery catheter to assist in the direction of the delivery catheter to the desired location in the pericardial space. Micro-camera systems suitable for use with the delivery catheter are well-known in the art. Further, a laser Doppler system may be extended through the lumen of the delivery catheter to assist in the direction of the delivery catheter. The delivery catheter is positioned such that the outlet of one of the lumens of the delivery catheter is adjacent to the external surface of the heart (e.g., the external surface of an atrium or a ventricle). A pacing lead is extended through the lumen of the delivery catheter onto the external surface of the heart. The pacing lead may be attached to the external surface of the heart, for example, by screwing the lead into the cardiac tissue. In addition, the pacing lead may be placed deeper into the cardiac tissue, for example in the subendocardial tissue, by screwing the lead further into the tissue. After the lead is placed in the proper position, the delivery catheter is withdrawn from the pericardial space and the body. The guide wire is withdrawn from the pericardial space and the body, and the engagement catheter is withdrawn from the body. 
     The disclosed embodiments can be used for subendocardial, as well as epicardial, pacing. While the placement of the leads is epicardial, the leads can be configured to have a long screw-like tip that reaches near the subendocardial wall. The tip of the lead can be made to be conducting and stimulatory to provide the pacing to the subendocardial region. In general, the lead length can be selected to pace transmurally at any site through the thickness of the heart wall. Those of skill in the art can decide whether epicardial, subendocardial, or some transmural location stimulation of the muscle is best for the patient in question. 
     While various embodiments of devices, systems, and methods for access mg the heart tissue have been described in considerable detail herein, the embodiments are merely offered by way of non-limiting examples of the disclosure described herein. Many variations and modifications of the embodiments described herein will be apparent to one of ordinary skill in the art in light of this disclosure. It will therefore be understood by those skilled in the art that various changes and modifications may be made, and equivalents may be substituted for elements thereof, without departing from the scope of the disclosure. Indeed, this disclosure is not intended to be exhaustive or to limit the scope of the disclosure. The scope of the disclosure is to be defined by the appended claims, and by their equivalents. 
     Further, in describing representative embodiments, the disclosure may have presented a method and/or process as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible. Therefore, the particular order of the steps disclosed herein should not be construed as limitations on the claims. In addition, the claims directed to a method and/or process should not be limited to the performance of their steps in the order written, and one skilled in the art can readily appreciate that the sequences may be varied and still remain within the spirit and scope of the present disclosure. 
     It is therefore intended that the disclosure will include, and this description and the appended claims will encompass, all modifications and changes apparent to those of ordinary skill in the art based on this disclosure.