Patent Publication Number: US-8968230-B2

Title: Coil occlusion devices and systems and methods of using the same

Description:
PRIORITY 
     The present application (i) is related to, and claims the priority benefit of, U.S. Provisional Patent Application Ser. No. 61/543,330, filed Oct. 5, 2011, and (ii) is related to, claims the priority benefit of, and is a continuation-in-part of, U.S. Nonprovisional patent application Ser. No. 13/221,514, filed Aug. 30, 2011, which is related to, claims the priority benefit of, and is a continuation-in-part of, U.S. Nonprovisional patent application Ser. No. 13/092,803, filed Apr. 22, 2011, which is related to, claims the priority benefit of, and is a continuation-in-part of, U.S. Nonprovisional patent application Ser. No. 13/124,512, filed Apr. 21, 2011, which is related to, claims the priority benefit of, and is a U.S. §371 national stage application of, International Patent Application Serial No. PCT/US2008/087863, filed Dec. 19, 2008. The contents of each of these applications are incorporated by reference in their entirety into this disclosure. 
    
    
     BACKGROUND 
     While direct surgical and percutaneous revascularization through procedures such as a percutaneous transluminal coronary angioplasty (“PTCA”) or coronary artery bypass grafting (“CABG”) remain the mainstay of treatment for patients with angina and coronary artery disease (“CAD”), there are many patients that are not amenable to such conventional revascularization therapies. Because of this, much effort has been made to find alternative methods of revascularization for ischemic cardiac patients who are not candidates for revascularization by conventional techniques. Such patients are generally identified as “no-option” patients because there is no conventional therapeutic option available to treat their condition. As described in detail herein, the present disclosure provides various embodiments of devices to address such chronic conditions. 
     In addition, and as described in detail herein, the present disclosure provides various embodiments of devices that can be used acutely to treat patients with a number of conditions, such as S-T segment elevated myocardial infarction (STEMI) or cardiogenic shock or patients who require high risk percutaneous coronary intervention, until they can receive more traditional therapy. 
     Currently, there are multiple specific conditions for which conventional revascularization techniques are known to be ineffective as a treatment. Two specific examples of such cardiac conditions include, without limitation, diffuse CAD and refractory angina. Furthermore, a percentage of all patients diagnosed with symptomatic CAD are not suitable for CABG or PTCA. In addition and for various reasons discussed below, diabetic patients—especially those with type 2 diabetes—exhibit an increased risk for CAD that is not effectively treated by conventional revascularization techniques. 
     There is currently little data available on the prevalence and prognosis of patients with symptomatic CAD that is not amenable to revascularization through conventional methods. However, one study indicated that out of five hundred (500) patients with symptomatic CAD who were considering direct myocardial revascularization and angiogenesis, almost twelve percent (12%) were not suitable for CABG or PTCA for various reasons. Furthermore, in general, patients with atherosclerotic involvement of the distal coronary arteries have high mortality and morbidity. For example, a study conducted on patients indicated that, one (1) year after being diagnosed with atherosclerotic involvement of the distal coronary arteries, 39.2% of such patients had a cardiac-related death, 37.2% had an acute myocardial infarction, and 5.8% had developed congestive heart failure. Overall, 82.2% of the patients with atherosclerotic involvement of distal coronary arteries had developed or experienced a significant cardiac event within one (1) year. 
     A. Diffuse CAD and Refractory Angina 
     CAD is typically not focal (i.e. limited to one point or a small region of the coronary artery), but rather diffused over a large length of the entire vessel, which is termed “diffuse CAD.” Several studies indicate that patients with a diffusely diseased coronary artery for whom standard CABG techniques cannot be successfully performed constitute about 0.8% to about 25.1% of all patients diagnosed with CAD. Furthermore, it is believed that diffuse CAD is much more common than conventionally diagnosed because it is often difficult to detect by an angiogram due to the two-dimensional views. 
     Practitioners have realized that the quality of a patient&#39;s distal coronary arteries is one of the critical factors related to a successful outcome of a surgical revascularization. As previously indicated, there is considerable evidence that CABG for vessels having diffuse CAD results in a relatively poor outcome. In fact, studies have indicated that diffuse CAD is a strong independent predictor of death after a CABG procedure. Further, as previously noted conventional revascularization techniques have also proven ineffective on a subgroup of patients with medically refractory angina. In line with the aforementioned reasoning, this is likely because patients with medically refractory angina have small or diffusely diseased distal vessels that are not amenable to conventional revascularization therapies. Accordingly, patients exhibiting diffuse CAD or medically refractory angina are often considered no-option patients and not offered bypass surgery, PTCA, or other conventional procedures. 
     B. Diabetes as a Risk Factor 
     Diabetes is an important risk factor for the development of CAD, diffuse or asymptomatic, and it has been estimated that approximately seventy-five percent (75%) of the deaths in diabetic patients are likely attributed to CAD. It is estimated that 16 million Americans have diabetes, without only 10 million being diagnosed. Patients with diabetes develop CAD at an accelerated rate and have a higher incidence of heart failure, myocardial infarction, and cardiac death than non-diabetics. 
     According to recent projections, the prevalence of diabetes in the United States is predicted to be about ten percent (10%) of the population by 2025. Further, the increasing prevalence of obesity and sedentary lifestyles throughout developed countries around the world is expected to drive the worldwide number of individuals with diabetes to more than 330 million by the year 2025. As may be expected, the burden of cardiovascular disease and premature mortality that is associated with diabetes will also substantially increase, reflecting in not only an increased amount of individuals with CAD, but an increased number of younger adults and adolescents with type 2 diabetes who are at a two- to four-fold higher risk of experiencing a cardiovascular-related death as compared to non-diabetics. 
     In addition to developing CAD at an accelerated rate, CAD in diabetic patients is typically detected in an advanced stage, as opposed to when the disease is premature and symptomatic. Consequently, when diabetic patients are finally diagnosed with CAD they commonly exhibit more extensive coronary atherosclerosis and their epicardial vessels are less amendable to interventional treatment, as compared to the non-diabetic population. Moreover, as compared with non-diabetic patients, diabetic patients have lower ejection fractions in general and therefore have an increased chance of suffering from silent myocardial infarctions. 
     C. No-Option Patients 
     Some studies have shown that two-thirds (⅔rds) of the patients who were not offered bypass surgery, because of diffuse CAD or otherwise, either died or had a non-fatal myocardial infarction within twelve (12) months. Furthermore, patients diagnosed with diffuse CAD ran a two-fold increased risk of in-hospital death or major morbidity, and their survival rate at two (2) years was worse than those patients who exhibited non-diffuse CAD or other complicating conditions. As previously indicated, the majority of these patients are considered no-option patients and are frequently denied bypass surgery as it is believed that CABG would result in a poor outcome. 
     Due to the increasing numbers of no-option patients and a trend in cardiac surgery towards more aggressive coronary interventions, a growing percentage of patients with diffuse CAD and other no-option indications are being approved for coronary bypass surgery because, in effect, there are no other meaningful treatment or therapeutic options. Some effects of this trend are that the practice of coronary bypass surgery has undergone significant changes due to the aggressive use of coronary stents and the clinical profiles of patients referred for CABG are declining. As such, performing effective and successful coronary bypass surgeries is becoming much more challenging. Bypass grafting diffusely diseased vessels typically requires the use of innovative operations such as on-lay patches, endarterectomies and more than one graft for a single vessel. Patients with “full metal jackets” (or multiple stents) are typically not referred to cardiac surgeons and often end up as no-option patients despite the attempts of using these innovative surgeries. 
     In recent decades, the spectrum of patients referred for CABG are older and are afflicted with other morbidities such as hypertension, diabetes mellitus, cerebral and peripheral vascular disease, renal dysfunction, and chronic pulmonary disease. In addition, many patients referred for CABG have advanced diffuse CAD and have previously undergone at least one catheter-based intervention or surgical revascularization procedure that either failed or was not effective. Because of this, the patient&#39;s vessels may no longer be graftable and complete revascularization using conventional CABG may not be feasible. An incomplete myocardial revascularization procedure has been shown to adversely affect short-term and long-term outcomes after coronary surgery. 
     Due in part to some of the aforementioned reasons, reoperative CABG surgery is now commonplace, accounting for over twenty percent (20%) of cases in some clinics. It is well established that mortality for reoperative CABG operations is significantly higher than primary operations. As such, the risk profile of reoperative patients is significantly increased and such patients are subjected to an increased risk of both in-hospital and long-term adverse outcomes. 
     Further, clinicians have also turned to unconventional therapies to treat non-option patients. For example, coronary endarterectomy (“CE”) has been used as an adjunct to CABG in a select group of patients with diffuse CAD in order to afford complete revascularization. However, while CE was first described in 1957 as a method of treating CAD without using cardiopulmonary bypass and CABG, this procedure has been associated with high postoperative morbidity and mortality rates and has been afforded much scrutiny. Nevertheless, CE is the only therapeutic option available for many no-option patients with diffuse CAD. 
     Similarly, because conventional therapies have proven ineffective or are unavailable to high risk patients, perioperative transmyocardial revascularization (“TMR”) has been indicated for patients suffering from medically refractory angina. TMR has proven effective for most patients suffering from refractory angina; the mortality rate after TMR in patients with stable angina ranges between about one to twenty percent (1-20%). Furthermore, in one study, TMR resulted in a higher perioperatively mortality rate in patients with unstable angina than those with stable angina (27% versus 1%). Some even report an operative mortality rate as low as twelve percent (12%). Patients who experience angina and who cannot be weaned from intravenous nitroglycerin and heparin have a significantly higher operative mortality rate (16-27% versus 1-3%). Based on these findings, the clinical practice has been to avoid taking such patients to the operating room for TMR if at all possible. The success of TMR is thought to be due to improved regional blood flow to ischemic myocardium, but the precise mechanisms of its effects remain unclear. 
     D. Acute Applications 
     When a coronary artery becomes blocked, the flow of blood to the myocardium stops and the muscle is damaged. This process is known as myocardial infarction (MI). An MI can damage the myocardium, resulting in a scarred area that does not function properly. MI has an annual incidence rate of 1.5 million in the US and is the primary driver of roughly 500,000 cases of mortality and high morbidity rates in CAD patients. Immediate reperfusion of the myocardium following MI is clinically desirable to preserve as much heart tissue as possible. Current revascularization options include thrombolytic medications, percutaneous coronary intervention (PCI), or coronary artery bypass graft (CABG). While thrombolytic compounds can be administered swiftly in an acute care facility, the vast majority of MI patients require a PCI or CABG to adequately restore reliable blood flow to the heart tissue. Both of these revascularization techniques are clinically safe and effective, however, they require specialized staff and facilities, which are not available at all acute care facilities, or not available soon enough to preserve enough myocardial tissue in the wake of an MI. A significant effort has been undertaken in recent years to speed MI patients to the cath lab for PCI upon presenting, but these programs are not available everywhere, and even where available, do not often meet the 90 minute target of door to balloon time. 
     In the US, nearly 75,000 CAD patients annually present with atherosclerosis of the left main coronary artery (LMCA). The LMCA delivers oxygenated blood to 75% or more of the myocardium. An untreated, diseased LMCA results in 20% 1-year and 50% 7- to 10-year mortality rates. Historically, PCI of the LMCA (LMPCI) has been deemed too risky, however, recent advances in technique and tools have begun to allow an expanded LMCA patient population for PCI, especially in certain patient conditions where PCI is preferable to CABG (e.g., patients who are aging, delicate, and/or in critical condition). 
     The risks of LMPCI include prolonged myocardial ischemia from balloon inflations, “no-reflow phenomenon” (2-5% incidence rate), or coronary artery dissections (30% incidence rate). Existing circulatory support devices used to address these hemodynamic issues, such as the intra-aortic balloon pump (IABP) and left ventricle circulatory support devices (e.g., Impella 2.5), are unable to sufficiently meet the myocardium oxygen demands even though cardiac pumping mechanics are improved. The assistance from these devices is limited further during no-reflow and coronary artery dissection events. In addition, the clinically superior left ventricle circulatory support devices are complicated to use and require dedicated training and facilities, which has prevented wide-spread clinical adoption. 
     There are over 35,000 cardiogenic shock (CS) patients each year in the US. This condition severely complicates an MI event with in-hospital mortality rates exceeding 50 percent. PCI is the standard of care for these acute patients; however, the CS patient must be stabilized prior to intervention, according to ACC/AHA guidelines, using a short-term circulatory support device as a bridge. An IABP or left ventricle circulatory support device (e.g. Impella 2.5) can currently be utilized in these cases to stabilize the heart while awaiting revascularization. 
     The 200,000 S-T segment elevated MI (STEMI) patients per year in the US require immediate reperfusion of the myocardium. Thrombolytic medications are administered as the primary revascularization technique, however, 70 percent of those receiving thrombolysis fail to respond. Furthermore, 10 percent of those that initially respond to thrombolysis experience reocclusion while still an in-patient. These STEMI patients require clinically superior rescue PCI, as opposed to repeated thrombolysis. 
     Because only 1,200 out of 5,000 acute care hospitals are capable of performing PCI (and even fewer are capable of CABG), nearly 60 percent of STEMI patients do not achieve the required 90 minute time-frame for revascularization. 
     While awaiting revascularization, IAPB currently is the preferred circulatory assist device and is indicated for use by critical care unit (CCU), intensive care unit (ICU) and emergency medicine (ER) physicians in a variety of clinical settings. However, the IABP&#39;s use in MI events remains at less than 5 percent of cases due to complicated training and device-related malfunctions in 12-30% of all cases. 
     Circulatory support devices used in these cases have two major problems: inability to adequately augment blood flow in flow-limiting atherosclerotic coronary arteries to a damaged myocardium, and 12-30% device complication incidence rates, including peripheral ischemia, compartment syndrome, infection, hematological issues, and mechanical issues. 
     Certain patients requiring coronary bypass surgery, for example, may not have sufficient vasculature suitable for grafting in connection with the surgery. Said vasculature would need to be sufficiently strong as to withstand the relatively high arterial pressures as compared to the relatively low venous pressures. 
     In view of the same, devices, systems, and methods useful to facilitate arterialization of veins for use in connection with bypass surgeries, for example, would be well-received in the marketplace. 
     BRIEF SUMMARY 
     In an exemplary embodiment of an occluder device of the present disclosure, the occluder device comprises a coil having at least a first, uncompressed (or expanded) configuration and a second, compressed (or retracted) configuration, wherein the coil in the first, uncompressed (or expanded) configuration is capable of fitting within a delivery mechanism sized and shaped to fit within a mammalian luminal organ, and wherein the mammalian luminal organ is occluded when the coil is positioned therein in the second, compressed (or retracted) configuration. 
     In an exemplary embodiment of an occluder system of the present disclosure, the system comprises an exemplary occluder device of the present disclosure, and a delivery mechanism sized and shaped to fit within a mammalian luminal organ, the delivery mechanism configured to receive an exemplary occluder device therethrough. 
     In an exemplary embodiment of an occluder system of the present disclosure, the system comprises a coil having at least a first, uncompressed configuration and a second, compressed configuration, a delivery mechanism sized and shaped to fit within a mammalian luminal organ, the delivery mechanism configured to receive the coil within a lumen defined within the delivery mechanism, and a pusher configured to fit within the lumen of the delivery mechanism and further configured to facilitate placement of the coil within the mammalian luminal organ. In another embodiment, the system further comprises a guidewire configured to fit within the mammalian luminal organ and further configured to fit within the lumen of the delivery mechanism. In yet another embodiment, the coil in the first, uncompressed configuration is capable of fitting within the delivery mechanism, and the coil in the second, compressed configuration is capable of occluding a mammalian luminal organ. In an additional embodiment, the coil is capable of changing from the first, uncompressed configuration to the second, compressed configuration when the coil is engaged by the pusher. 
     In an exemplary embodiment of an occluder system of the present disclosure, the pusher comprises a shaft and a tip. In an additional embodiment, the tip is relatively or completely circular in shape and configured to prevent the coil from moving past the pusher within the delivery mechanism. In yet an additional embodiment, the delivery mechanism comprises a delivery catheter having a wall and defining a lumen therethrough. In another embodiment, the delivery mechanism is sized and shaped to fit within a patient&#39;s vein. In yet another embodiment, the coil is capable of changing from the first, uncompressed configuration to the second, compressed configuration and back to the first, uncompressed configuration. 
     In an exemplary embodiment of an occluder device of the present disclosure, the occluder device comprises a coil having at least a first, uncompressed configuration and a second, compressed configuration, wherein the coil in the first, uncompressed configuration is capable of fitting within a delivery mechanism sized and shaped to fit within a mammalian luminal organ, and wherein the coil in the second, compressed configuration is capable of occluding a mammalian luminal organ. In another embodiment, the coil is capable of changing from the first, uncompressed configuration to the second, compressed configuration when the coil is engaged by a pusher sized and shaped to fit within the delivery mechanism. In yet another embodiment, the pusher comprises a shaft and a tip. In an additional embodiment, the tip is relatively or completely circular in shape and configured to prevent the coil from moving past the pusher within the delivery mechanism. 
     In an exemplary embodiment of an occluder device of the present disclosure, the delivery mechanism comprises a delivery catheter having a wall and defining a lumen therethrough. In an additional embodiment, the delivery mechanism is sized and shaped to fit within a patient&#39;s vein. In yet an additional embodiment, the coil is capable of changing from the first, uncompressed configuration to the second, compressed configuration and back to the first, uncompressed configuration. In another embodiment, the coil is capable of changing from the first, uncompressed configuration to the second, compressed configuration when the coil is engaged by a pusher sized and shaped to fit within the delivery mechanism, wherein the delivery mechanism comprises a delivery catheter having a wall and defining a lumen therethrough, wherein the delivery mechanism is sized and shaped to fit within a patient&#39;s vein, and wherein the coil is capable of changing from the first, uncompressed configuration to the second, compressed configuration and back to the first, uncompressed configuration. 
     In an exemplary embodiment of an occluder device of the present disclosure, the coil comprises a material selected from the group consisting of nitinol and stainless steel. In an additional embodiment, the coil is at least partially coated by a material selected from the group consisting of polytetrafluoroethylene, polyethylene terephthalate, and polyurethane. In another embodiment, the coil is radiopaque. 
     In an exemplary embodiment of a method of using an occluder device of the present disclosure, the method comprising the steps of introducing an exemplary occlusion device of the present disclosure into a patient&#39;s body, the occlusion device positioned within a lumen of an exemplary delivery mechanism of the present disclosure, advancing at least part of the delivery mechanism to a desired location within the patient&#39;s body, advancing the exemplary occluder device directly into a luminal organ within the patient&#39;s body, and compressing the exemplary occluder device within the luminal organ to occlude the luminal organ. In another embodiment, the introducing step includes the steps of introducing a guidewire into the patient&#39;s body, advancing a delivery mechanism of the present disclosure into the patient&#39;s body over the guidewire, and removing the guidewire from the patient&#39;s body. In yet another embodiment, the luminal organ comprises a vein. In an additional embodiment, the step of advancing the exemplary occluder device directly into the luminal organ is performed by using a pusher positioned within the delivery mechanism to advance the exemplary occluder device. In yet an additional embodiment, the step of compressing the exemplary occluder device within the luminal organ is performed by using a pusher positioned within the delivery mechanism to compress the exemplary occluder device 
     In an exemplary embodiment of a method of using an occluder device of the present disclosure, the compressing step is performed to facilitate a configuration change of the exemplary occluder device from a first uncompressed or otherwise non-occlusive configuration to a second compressed or otherwise occlusive configuration. In an additional embodiment, the method further comprises the step of withdrawing the delivery mechanism and the pusher from the patient&#39;s body. In yet an additional embodiment, the method further comprises the steps of excising an arterialized vein from the patient&#39;s body, the arterialized vein located at or near the compressed exemplary occluder device, and grafting the arterialized vein into the patient&#39;s arterial system. In another embodiment, the method further comprises the step of performing a retroperfusion procedure while the exemplary occluder device is compressed within the luminal organ and/or after the step of excising the arterialized vein. In yet another embodiment, the step of advancing at least part of the delivery mechanism to a desired location within the patient&#39;s body is performed by advancing at least part of the delivery mechanism into a heart of the patient, through a coronary sinus, and into a cardiac vein. In an additional embodiment, the step of advancing the exemplary occluder device directly into the luminal organ within the patient&#39;s body is performed by advancing the exemplary occluder device directly into the cardiac vein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosed embodiments and other features, advantages, and disclosures contained herein, and the matter of attaining them, will become apparent and the present disclosure will be better understood by reference to the following description of various exemplary embodiments of the present disclosure taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  shows a side view of a catheter for placement within an arterial vessel and that may be used to deliver retroperfusion therapy, according to at least one embodiment of the present disclosure; 
         FIG. 2A  shows a side view of the catheter of  FIG. 1  in a collapsed position, according to at least one embodiment of the present disclosure; 
         FIG. 2B  shows a side view of the catheter of  FIG. 1  in an extended position, according to at least one embodiment of the present disclosure; 
         FIG. 3  shows a side view of an autoretroperfusion system positioned to deliver retroperfusion therapy to a heart, according to at least one embodiment of the present disclosure; 
         FIGS. 4A and 4B  show perspective views of the distal end of a venous catheter used in the autoretroperfusion system of  FIG. 3 , according to at least one embodiment of the present disclosure; 
         FIG. 5  shows the components of an autoretroperfusion system that can be used to deliver retroperfusion therapy to ischemic tissue, according to at least one embodiment of the present disclosure; 
         FIG. 6  shows a view of the base and diaphragmatic surface of a heart with the distal ends of two components of the autoretroperfusion system of  FIG. 5  positioned therein such that the autoretroperfusion system can deliver simultaneous selective autoretroperfusion therapy thereto, according to at least one embodiment of the present disclosure; 
         FIG. 7  shows a flow chart of a method for delivering autoretroperfusion therapy, according to at least one embodiment of the present disclosure; 
         FIG. 8A  shows a side view of the catheter of  FIG. 1  in a collapsed position within an introducer, according to at least one embodiment of the present disclosure; 
         FIG. 8B , shows a side view of the catheter of  FIG. 1  being introduced via an introducer into an arterial vessel, according to at least one embodiment of the present disclosure; 
         FIGS. 8C and 8D  show side views of the introducer of  FIG. 8A  being removed from an arterial vessel, thereby deploying the projection cannula of the catheter of  FIG. 1 , according to at least one embodiment of the present disclosure; 
         FIG. 8E  shows a side view of the catheter of  FIG. 1  anchored within an arterial vessel through the use of an expandable balloon, according to at least one embodiment of the present disclosure; 
         FIG. 9  shows a schematic view of the autoretroperfusion system of  FIG. 5  as applied to a heart, according to at least one embodiment of the present disclosure; 
         FIG. 10  shows a schematic view of the autoretroperfusion system of  FIG. 5  as applied to a heart, according to at least one embodiment of the present disclosure; 
         FIG. 11  shows a schematic view of a step of the method of  FIG. 7  as the method is applied to a heart, according to at least one embodiment of the present disclosure; 
         FIG. 12  shows a flow chart of a method for delivering simultaneously selective autoretroperfusion therapy, according to at least one embodiment of the present disclosure; 
         FIG. 13  shows a schematic view of a step of the method of  FIG. 12  as the method is applied to a heart, according to at least one embodiment of the present disclosure; 
         FIG. 14  shows a schematic view of a step of the method of  FIG. 12  as the method is applied to a heart, according to at least one embodiment of the present disclosure; 
         FIG. 15  shows an exemplary retroperfusion system, according to at least one embodiment of the present disclosure; 
         FIG. 16  shows a portion of an exemplary retroperfusion system, according to at least one embodiment of the present disclosure; and 
         FIG. 17  shows a block diagram of components of an exemplary retroperfusion system coupled to a blood supply, according to at least one embodiment of the present disclosure; 
         FIG. 18  shows a schematic of the retroperfusion system showing the arterial and retroperfusion catheters, according to a study in connection with the present disclosure; 
         FIG. 19  shows a diagram of steps of an exemplary method of organ perfusion, according to at least one embodiment of the present disclosure; 
         FIG. 20  shows an exemplary occluder device in a first configuration within a delivery mechanism, according to an exemplary embodiment of the present disclosure; 
         FIG. 21  shows a an exemplary occluder device in a second configuration within a patient&#39;s luminal organ, according to an exemplary embodiment of the present disclosure; 
         FIG. 22A  shows an exemplary occluder device in a first configuration within a delivery mechanism within a patient&#39;s coronary vein, according to an exemplary embodiment of the present disclosure; 
         FIG. 22B  shows a an exemplary occluder device in a second configuration within a patient&#39;s coronary vein, according to an exemplary embodiment of the present disclosure; 
         FIG. 22C  shows an exemplary occluder device in a first configuration within a delivery mechanism positioned through a patient&#39;s heart and within a patient&#39;s coronary vein, according to an exemplary embodiment of the present disclosure; 
         FIG. 23  shows a block diagram of a system having an exemplary occluder device, according to an exemplary embodiment of the present disclosure; and 
         FIG. 24  shows a diagram of method steps, according to an exemplary embodiment of the present disclosure. 
     
    
    
     An overview of the features, functions and/or configurations of the components depicted in the various figures will now be presented. It should be appreciated that not all of the features of the components of the figures are necessarily described. Some of these non-discussed features, such as various couplers, etc., as well as discussed features are inherent from the figures themselves. Other non-discussed features may be inherent in component geometry and/or configuration. 
     DETAILED DESCRIPTION 
     The embodiments discussed herein include devices, systems, and methods useful for providing selective autoretroperfusion to the venous system. In addition, and with various embodiments of devices and systems of the present disclosure, said devices and/or systems can also be used to achieve a controlled arterialization of the venous system. Furthermore, various devices, systems, and methods for occluding a vessel are provided herein. For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of this disclosure is thereby intended. 
     The devices, systems and methods disclosed herein can be used to safely and selectively arterialize venous vessels in order to decrease the stress thereon and prevent rupture of the same. Accordingly, through the use of the devices, systems and methods disclosed herein, long-term autoretroperfusion of oxygenated blood through the coronary venous system can be achieved, thereby providing a continuous supply of oxygen-rich blood to an ischemic area of a tissue or organ. While the devices, systems and methods disclosed herein are described in connection with a heart, it will be understood that such devices, systems and methods are not limited in their application solely to the heart and the same may be used in connection with any ischemic tissue and/or organ in need of an oxygen-rich blood supply. 
     Selective auto-retroperfusion (SARP) can be indicated for both chronic and acute applications, and exemplary catheters  10  and/or systems  100  of the present disclosure (and as referenced in further detail herein) can be used in connection therewith. References to “acute” for SARP applications are used generally to indicate the amount of time that an exemplary catheter  10  and/or system  100  of the present disclosure may be in use on a given patient. In at least one embodiment, catheter  10  and/or system  100 , or portions thereof, will be sterile and intended for disposal after a single use. In at least one embodiment of a system  100  useful in connection with an acute indication, use of system  100  could be limited to less than 24 hrs. 
     Now referring to  FIG. 1 , a side view of a catheter  10  is shown. The catheter  10  is configured to be placed within an arterial vessel and comprises a flexible, elongated tube having a proximal end  12 , a distal end  14  and at least one lumen  15  extending between the proximal end  12  and the distal end  14 . The dimensions of the catheter  10  may vary depending on the particulars of a specific patient or with respect to the artery to be cannulated. For example and without limitation, where the catheter  10  is used to in a system for autoretroperfusion of the coronary sinus, the catheter  10  may comprise a diameter of about 2.7 millimeters to about 4 millimeters (about 8 Fr to about 12 Fr). Furthermore, the at least one lumen  15  of the catheter  10  comprises a sufficient diameter such that blood can flow therethrough. In addition, the catheter  10  may be comprised of any appropriate material, including without limitation, polyurethane or silicone rubber. Furthermore, the catheter  10  may be coated with heparin or any other suitable anti-coagulant such that the catheter  10  may be placed within a vessel for an extended period of time without inhibiting blood flow due to coagulation. 
     The distal end  14  of the catheter  10  is configured to allow arterial blood to flow therethrough and into the at least one lumen  15  of the catheter  10 . Similarly, the proximal end  12  of the catheter  10  is configured to allow blood within the at least one lumen  15  to flow out of the catheter  10 . Accordingly, when the catheter  10  is positioned within an arterial vessel, the oxygenated blood is allowed to flow into the catheter  10  through the distal end  14  of the catheter  10 , through the at least one lumen  15 , and out of the catheter  10  through the proximal end  12  of the catheter  10 . In this manner, placement of the catheter  10  within a vessel does not inhibit the flow of blood through the vessel or significantly affect the pressure of the blood flow within the vessel. 
     As shown in  FIG. 1 , the catheter  10  further comprises a projection cannula  16  that extends from the proximal end  12  of the catheter  10  and forms a Y-shaped configuration therewith. The projection cannula  16  comprises a flexible tube of material that is appropriate for insertion within a vessel and placement within an opening in a vessel wall. Furthermore, the projection cannula  16  comprises at least one lumen  18 , a proximal end  20 , and a distal end  22 . The distal end  22  of the projection cannula  16  is coupled with the body of the catheter  10  and configured to allow the lumen  18  of the projection cannula  16  to communicate with at least one of the at least one lumens  15  of the catheter  10 . Accordingly, when blood flows through the at least one lumen of the catheter  10 , a portion of the blood flow enters the lumen  18  of the projection cannula  16  through the distal end  22  thereof and flows out through the proximal end  20  of the projection cannula  16 . In this manner, the catheter  10  is capable of bifurcating the flow of blood through the vessel in which it is inserted and routing some of that blood flow out of the vessel and to another location. 
     This bifurcation can be exploited to modify the pressure of the blood flowing through the projection cannula  16  and/or through the proximal end  12  of the catheter  10  by manipulating the dimensions of the projection cannula  16  and the body of the catheter  10 . For example, and without limitation, if the diameter of the projection cannula  16  is less than the diameter of the at least one lumen  15  of the catheter  10 , the majority of the blood will flow through the proximal end  12  of the catheter  10  and the pressure of the remaining blood that flows through the smaller projection cannula  16  will necessarily be reduced. Predictably, the smaller the diameter of the lumen  18  of the projection cannula  16 , the greater the pressure drop that can be achieved in the blood flowing through the lumen  18  of the projection cannula  16 . Accordingly, with respect to the catheter&#39;s  10  application to autoretroperfusion therapies, the projection cannula  16  can be used to re-route blood flow from an artery to a vein while simultaneously achieving the necessary pressure drop in the re-routed blood between the arterial system and unarterialized venous system. Moreover, the catheter  10  is capable of maintaining substantially normal blood flow through the artery in which it is housed as the arterial blood not re-routed through the projection cannula  16  is allowed to flow through the open proximal end  12  of the catheter  10  and back into the artery in the normal antegrade fashion. 
     Due to the configuration of the projection cannula  16  and the material of which it is comprised, the projection cannula  16  is capable of hingedly moving relative to the body of the catheter  10  between a collapsed position and an extended position. Now referring to  FIGS. 2A and 2B , the projection cannula  16  is shown in the collapsed position ( FIG. 2A ) and in the extended position ( FIG. 2B ). When the projection cannula  16  is in the collapsed position, the projection cannula  16  is positioned substantially parallel with the body of the catheter  10 . Alternatively, when the projection cannula  16  is in the extended position, the projection cannula  16  is positioned such that the projection cannula  16  forms an angle θ with the proximal end  12  of the catheter  10 . The value of angle θ may be selected depending on the desired application of the catheter  10 . For example, in at least one embodiment, the angle θ may comprise any value ranging between about 15° and about 90°. In another example, the angle θ may comprise about 45° when the projection cannula  16  is in the extended position. 
     The projection cannula  16  is biased such that, when it is not subject to a downward force, the projection cannula  16  rests in the expanded position. Conversely, when a downward force is applied to the projection cannula  16  by way of an introducer or otherwise, the projection cannula  16  moves into and remains in the collapsed position until the downward force is removed. In this manner, the projection cannula  16  may be introduced into a vessel in the collapsed position through the use of an introducer or shaft and thereafter move into the expanded position when the catheter  10  is properly positioned within the vessel and the introducer or shaft is removed. 
     Optionally, as shown in  FIG. 1 , the catheter  10  may further comprise an expandable balloon  58  coupled with an intermediary portion of the external surface of the catheter  10  such that the expandable balloon  58  encases the catheter  10  and the distal end  22  of the projection cannula  18 . The expandable balloon  58  may be any expandable balloon  58  that is appropriate for insertion within a vessel and may comprise any material suitable for this function, including without limitation, polyethylene, latex, polyestherurethane, polyurethane, sylastic, silicone rubber, or combinations thereof. In operation, the expandable balloon  58  can be used to anchor the catheter  10  in a desired position within a vessel wall and prevent leakage from the opening in the vessel wall through which the projection cannula  16  traverses. 
     The expandable balloon  58  is capable of being controlled by a clinician such that it can inflate and/or deflate to the proper size. The sizing of the expandable balloon  58  will differ between patients and applications. The expandable balloon  58  may be in fluid communication with a balloon inflation port  62  through a secondary lumen  60  within the lumen  18  of the projection cannula  16 . Alternatively, the expandable balloon  58  may be in fluid communication with the balloon inflation port  62  through a tube or other means that is positioned within the lumen  18  of the projection cannula  16  as shown in  FIG. 1 . The balloon port  62  may be positioned subcutaneously or otherwise such that a clinician can easily access the balloon port  62  when the catheter  10  is positioned within a vessel. In this manner the balloon port  62  can be accessed by a clinician, subcutaneously, percutaneously or otherwise, and used to inflate or deflate the expandable balloon  58  with no or minimal invasion to the patient. 
     Now referring to  FIG. 3 , an autoretroperfusion system  100  is shown positioned to allow arterial blood to irrigate the coronary sinus of a heart  101 . With respect to the heart  101 , the autoretroperfusion system  100  may be used for treatment of myocardial infarctions by injecting arterial blood into the coronary sinus in synchronism with the patient&#39;s heartbeat. Furthermore, the autoretroperfusion system  100  is capable of controlling the pressure of the arterial blood flow as it enters the venous vessel such that when the arterial blood flow is first introduced into the venous system, the pressure of the re-routed arterial blood flow is reduced to protect the thinner venous vessels. In this manner, the venous system is allowed to gradually arterialize. Further, after the selected venous vessel has sufficiently arterialized, the autoretroperfusion system  100  is capable of reducing or ceasing its influence on the pressure of the re-routed arterial blood flow such that the standard arterial blood flow pressure is thereafter allowed to flow into the arterialized venous vessel. 
     Autoretroperfusion system  100  comprises the catheter  10 , a second catheter  150 , and a connector  170 . The catheter  10  is for placement within an arterial vessel and is configured as previously described in connection with  FIGS. 1-2B . The second catheter  150  is configured for placement within the venous system. The connector  170  is configured to form an anastomosis between the catheter  10  and the second catheter  150  and further functions to monitor various data points on the blood flow flowing therethrough. In addition, in at least one embodiment, the connector  170  is capable of controlling the pressure of arterial blood flowing therethrough. 
     The second catheter  150  is configured for placement within a venous vessel wall  114  and comprises a flexible tube having a proximal end  152 , a distal end  154  and at least one lumen  156  extending between the proximal end  152  and the distal end  154 . Both the proximal end  152  and the distal end  154  of the second catheter  150  are open and in communication with the at least one lumen  156  of the second catheter  150 , thereby allowing blood to flow into the at least one lumen  156  through the proximal end  152  and out of the distal end  154  back into the venous vessel  114 . The second catheter  150  may be any catheter known in the art that is capable of intravascular insertion and advancement through the venous system and may comprise any appropriate material, including without limitation, polyurethane or silicone rubber. In at least one embodiment, the second catheter  150  is configured to receive a guidewire  510  (see  FIGS. 4A and 4B ) through the at least one lumen  156  to facilitate the intravascular delivery of the distal end  154  of the second catheter  150  into the desired location of the venous vessel  114 . Furthermore, similar to the catheter  10 , the second catheter  150  may be coated with heparin or any other suitable anti-coagulant prior to insertion in order to facilitate the extended placement of the second catheter  150  within the venous vessel  114 . Accordingly, the autoretroperfusion system  100  may be used to deliver chronic retroperfusion treatment to an ischemic area of a body. 
       FIGS. 4A and 4B  show side views of the distal end  154  of the second catheter  150  positioned within the venous vessel wall  114 . As shown in  FIG. 4A , the distal end  154  of the second catheter  150  may further comprise an expandable balloon  158  coupled with the external surface of the second catheter  150 . In operation, the expandable balloon  158  can be used to anchor the distal end  154  of the second catheter  150  in the desired location within the venous vessel wall  114 . The expandable balloon  158  may be any expandable balloon that is appropriate for insertion within a vessel and can be formed of any material suitable for this function, including without limitation, polyethylene, latex, polyestherurethane, polyurethane, sylastic, silicone rubber, or combinations thereof. 
     The expandable balloon  158  is capable of being controlled by a clinician such that it can inflate and/or deflate to the proper size. The sizing of the expandable balloon  158  will differ between patients and applications and it is often important to determine the proper sizing of the expandable balloon  158  to ensure the distal end  154  of the second catheter  150  is securely anchored within the desired location of the vessel wall  114 . The accurate size of the expandable balloon  158  can be determined through any technique known in the art, including without limitation, by measuring the compliance of the expandable balloon  158  ex vivo or in vivo. In addition, the distal end  154  of the second catheter  150  may further comprise a plurality of electrodes that are capable of accurately measuring the cross-sectional area of the vessel of interest as is known in the art. For example, the plurality of electrodes may comprise a combination of excitation and detection electrodes as described in detail in the currently pending U.S. patent application Ser. No. 11/891,981 entitled System and Method for Measuring Cross-Sectional Areas and Pressure Gradients in Luminal Organs, and filed on Aug. 14, 2007, which is hereby incorporated by reference in its entirety. In at least one embodiment, such electrodes may comprise impedence and conductance electrodes and may be used in connection with ports for the suction of fluid from the vessel and/or the infusion of fluid therein. 
     The expandable balloon  158  may be in fluid communication with a secondary lumen  160  disposed within the at least one lumen  156  of the second catheter  150 . In this example, the secondary lumen  160  is coupled with a balloon port  162  that extends from the proximal end  152  of the second catheter  150  (see  FIG. 3 ). Accordingly, when the autoretroperfusion system  100  is positioned within a patient, the balloon port  162  can be easily accessed by a clinician, subcutaneously, percutaneously or otherwise, and used to inflate or deflate the expandable balloon  158  with no or minimal invasion to the patient. 
     As shown in  FIGS. 4A and 4B , the distal end  154  of the second catheter  150  may further comprise at least one sensor  166  coupled therewith. In at least one embodiment, the at least one sensor  166  is disposed on the distal end  154  of the second catheter  150  distally of the expandable balloon  158 ; however, it will be understood that the at least one sensor  166  may be disposed in any location on the distal end  154  of the second catheter  150 . 
     The at least one sensor  166  may be used for monitoring purposes and, for example, may be capable of periodically or continuously monitoring the pressure of the blood flow flowing through the at least one lumen  156  of the first catheter  150  or the venous vessel  14  in which the second catheter  150  is inserted. Additionally, one of the at least one sensors  166  may be used to monitor the pH or the concentrations of carbon dioxide, lactate, or cardiac enzymes within the blood. Furthermore, the at least one sensor  166  is capable of wirelessly communicating the information it has gathered to a remote module through the use of telemetry technology, the internet, or other wireless means, such that the information can be easily accessed by a clinician on a real-time basis or otherwise. 
     Now referring back to  FIG. 3 , the autoretroperfusion system  100  further comprises a connector  170 . The connector  170  comprises any connector or quick connector known in the medical arts that is capable of forming an anastomosis between an artery and a vein such that oxygenated blood from the arterial system can flow into the venous system. For example, the connector  170  may comprise an annular connector that is capable of coupling with the proximal end  20  of the projection cannula  16  of the catheter  10  and with the proximal end  152  of the second catheter  150  such that arterial blood can flow continuously from the at least one lumen  15  of the catheter  10  to the at least one lumen  156  of the second catheter  150 . The connector  170  may be formed of any suitable material known in the art including, but not limited to, silicon rubber, poly(tetrafluoroethene), and/or polyurethane. 
     The connector  170  of the autoretroperfusion system  100  may comprise a pressure/flow regulator unit that is capable of measuring the flow rate of the blood moving therethrough, the pressure of the blood moving therethrough, and/or other data regarding the blood flowing through the anastomosis. The connector  170  may also be capable of transmitting such gathered data to a remote module  180  through a lead placed intravascularly or, in the alternative, through telemetry or another wireless means. The remote module  180  may comprise any device capable of receiving the data collected by the connector  170  and displaying the same. For example, and without limitation, the remote module  180  may comprise any display device known in the art or a computer, a microprocessor, hand-held computing device or other processing means. 
     Additionally, the connector  170  may further comprise a means for regulating the blood flow through the anastomosis. One of the main challenges of successfully delivering retroperfusion therapies is that the arterial blood pressure must be reduced prior to being introduced into a vein due to the thinner and more fragile anatomy of venous walls. Indeed, subjecting a non-arterialized venous vessel to the high pressures of arterial blood flow typically results in rupture of the venous vessel. Accordingly, with retroperfusion therapies, it is critical to ensure that the pressure of the arterial blood flow is at least initially controlled such that the venous vessel can arterialize prior to being subjected to the unregulated pressure of the arterial blood flow. 
     In at least one embodiment the connector  170  may comprise an external compression device to facilitate the control of the flow rate of the blood moving through the anastomosis. Alternatively, other means that are known in the art may be employed to regulate the blood flow and pressure of the blood flowing through the anastomosis formed by the connector  170 . In at least one embodiment, the means for regulating the blood flow through the anastomosis formed by the connector  170  is capable of regulating the pressure and/or flow velocity of the blood flowing through the anastomosis. For example, the means for regulating blood flow can be adjusted to ensure that about a 50 mg Hg pressure drop occurs in the blood flow between the arterial vessel and the venous vessel. 
     The connector  170  is capable of not only transmitting data to the remote module  180 , but also receiving commands from the remote module  180  and adjusting the means for regulating blood flow pursuant to such commands. Accordingly, when the autoretroperfusion system  100  is positioned within a patient for retroperfusion therapy, a clinician can use the remote module  180  to view the blood flow data collected by the connector  170  and non-invasively adjust the connector  170  to achieve the desired pressure and/or flow through the anastomosis. Such remote control of the connector  170  is particularly useful as a clinician may incrementally decrease the connector&#39;s  170  regulation of the blood flow without surgical intervention during the venous arterialization process and/or after the venous vessel arterializes. 
     Further, where the remote module  180  comprises a computer or other processing means, the remote module  180  is also capable of being programmed to automatically analyze the data received from the connector  170  and, based on the results thereof, suggest how to adjust the means of regulating the blood flow of the connector  170  and/or automatically adjust the means of regulating the blood flow of the connector  170  to achieve the optimal result. For example, and without limitation, when the autoretroperfusion system  100  is implanted into a patient and the anastomosis is first performed, the remote module  180  can automatically adjust the means for regulating the blood flow of the connector  170  based on the initial blood flow data received by the remote module  180 . In this manner, the desired pressure drop between the arterial system and the venous system is immediately achieved and the risk of venous rupture is significantly reduced. 
     Alternatively, where the connector  170  of the autoretroperfusion system  100  does not comprise a means for regulating blood flow, the gradual arterialization of the venous vessel can be achieved through other techniques known in the art. For example, in at least one embodiment, the autoretroperfusion system  100  further comprises a coil designed to at least partially occlude the vein of interest. In this manner, the pressure is allowed to build in front of the portion of the vein at least partially occluded by the coil and the vein gradually arterializes. In this at least one embodiment, the coil may comprise a metallic memory coil (made of nitinol, stainless steel or other acceptable materials that are radioopaque) and is covered with polytetrafluorethylene, polyethylene terephthalate, polyurethane or any other protective covering available in the medical arts. 
     Additionally, gradual arterialization can be performed by the second catheter  150 . In this embodiment of autoretroperfusion system  100 , the at least one lumen  156  of the second catheter  150  is designed to provide an optimal stenosis geometry to facilitate the desired pressure drop as the arterial blood flows therethrough and into the venous system. For example, and without limitation, the at least one lumen  156  may further comprise an internal balloon or resorbable stenosis as disclosed in International Patent Application No. PCT/US2006/029223, entitled “Devices and Methods for Controlling Blood Perfusion Pressure Using a Retrograde Cannula,” filed Jul. 28, 2006, which is hereby incorporated by reference herein. 
     In at least one embodiment, the stenosis comprises an internal expandable balloon (not shown) positioned within the lumen  156  of the second catheter  150 . In this at least one embodiment, the internal expandable balloon can be used to provide a pressure drop between the arterial and venous systems as is required to achieve the gradual arterialization of the target vein. The internal expandable balloon and the external expandable balloon  158  of the second catheter  150  may positioned concentrically or, alternatively, the internal expandable balloon and the expandable balloon  158  may be coupled with distinct portions of the second catheter  150 . 
     The internal expandable balloon may comprise any material suitable in the medical arts, including, without limitation, polyethylene, latex, polyestherurethane, polyurethane, sylastic, silicone rubber, or combinations thereof. Further, the internal expandable balloon may be in fluid communication with a tertiary lumen (not shown) disposed within the at least one lumen  156  of the second catheter  150 . In this embodiment, the tertiary lumen is also in fluid communication with an internal balloon port that extends from the proximal end  152  of the second catheter  150 . Accordingly, the internal balloon port can be easily accessed by a clinician, subcutaneously, percutaneously or otherwise, and the internal balloon port can be used to inflate or deflate the internal expandable balloon with minimal or no discomfort to the patient when the system  100  is in operation. Alternatively, the internal expandable balloon may be in fluid communication with the at least one lumen  156  of the second catheter  150 . In this example, the arterial blood flow through the at least one lumen  156  functions to inflate and deflate the internal expandable balloon in conjunction with the systolic and diastolic components of a heart beat. 
     The internal expandable balloon may be sized to a specific configuration in order to achieve the desired stenosis. In one embodiment, the size of the desired stenosis may be obtained by measuring the pressure at the tip of the distal end  156  of the second catheter  150  with the at least one sensor  166  while the internal expandable balloon is being inflated. Once the desired intermediate pressure is obtained, the internal expandable balloon volume may then be finalized and the vein is thereafter allowed to arterialize at the modified pressure for a defined period of time. At the end of the defined period (typically about 2-3 weeks), the internal expandable balloon may be removed from the at least one lumen  156  of the second catheter  150 . 
     Insertion and/or removal of the internal expandable balloon from the system  100  may be achieved through the internal balloon port and the related tertiary lumen of the second catheter  150 . For example, if the internal expandable balloon is no longer necessary to control the pressure on the venous system because the arterialization of the vein is substantially complete, the internal expandable balloon can be deflated through use of internal balloon port and withdrawn from the system  100  through the tertiary lumen and the internal balloon port. 
     Other embodiments of the system  100  may comprise other suitable means for providing a stenosis within the at least one lumen  156  of the second catheter  150  such that a pressure drop is achieved in blood flowing therethrough. For example, while a stenosis can be imposed by inflation of the internal expandable balloon, it may also be imposed through positioning a resorbable material within the at least one lumen  156  of the second catheter  150 . The resorbable stenosis may be comprised of a variety of materials including, for example and without limitation, magnesium alloy and polyols such as mannitol, sorbitol and maltitol. The degradation rate of the resulting resorbable stenosis will be dependent, at least in part, upon on what type of material(s) is selected to make-up the resorbable stenosis and the same may be manipulated to achieve the desired effect. 
     In addition to the aforementioned components of the autoretroperfusion system  100 , the autoretroperfusion system  100  may further include a first graft  185  and a second graft  190  as shown in  FIG. 3 . In this embodiment, the first graft  185  is coupled with the proximal end  20  of the projection cannula  16  (that extends through the exterior arterial wall  116 ) and the connector  170 . Further, the second graft  190  is coupled with the proximal end  152  of the second catheter  150  (positioned within the venous vessel wall  114 ) and the connector  170 . Accordingly, in this at least one embodiment, the second graft  190  is capable of traversing the venous vessel wall  114  in such a manner that the anastomosis is sealed and no blood flow is allowed to leak from the anastomosed vein  114 . 
     In this manner, the first and second grafts  185 ,  190  facilitate the formation of an elongated anastomosis between the venous and arterial vessels  114 ,  116  and thereby relieve any pressure that may be applied to the two vessels  114 ,  116  due to the anastomosis formed therebetween. For example and without limitation, in at least one embodiment the combined length of the grafts  185 ,  190  and the connector  170  is about 6 centimeters. However, it will be understood that the grafts  185 ,  190  may comprise any length(s) so long as the dimensions allow for an anastomosis to form between the applicable vessels and a fully developed blood flow is achieved from the artery to the venous vessel of interest. 
     Alternatively, the autoretroperfusion system  100  may only comprise the second graft  190  in addition to the catheter  10 , the second catheter  150  and the connector  170 . In this embodiment, the connector  170  is coupled with the proximal end  20  of the projection cannula  16  and the second graft  190 . Furthermore, the second graft  190  is further coupled with the proximal end  152  of the second catheter  150  such that the second graft  190  traverses an opening within the venous vessel wall  114  (see  FIG. 5 ). 
     The grafts  185 ,  190  may comprise any biocompatible, non-resorbable material having the necessary strength to support the surrounding tissue and withstand the pressure asserted by the blood flow therethrough. Furthermore, the grafts  185 ,  190  must exhibit the necessary flexibility to form an anastomosis between the vein and the artery within which the catheter  10  and the second catheter  150  are respectively housed. For example, and without limitation, the grafts  185 ,  190  may comprise any conventional implant including synthetic and natural prosthesis, grafts, and the like. The grafts  185 ,  190  may also comprise a variety of suitable materials, including those conventionally used in anastomosis procedures, including, without limitation, natural and synthetic materials such as heterologous tissue, homologous tissue, polymeric materials, Dacron, fluoropolymers, and polyurethanes. For example, and without limitation, the first and second grafts  185 ,  190  may comprise a material such as GORE-TEX (polytetraflouroethylene). The grafts  185 ,  190  may be coated with heparin or any other suitable anti-coagulant. Accordingly, the first graft  185  and the second graft  190  may be placed within a vessel or have blood flow therethrough for an extended period of time without inhibiting blood flow due to coagulation. 
     In at least one embodiment of the autoretroperfusion system  100 , the components of the system  100  are available in a package. Here, the package may also contain at least one sterile syringe containing the fluid to be injected into the balloon port  62  to inflate the expandable balloon  58  of the catheter  10  and/or the balloon port  162  to inflate the expandable balloon  158  of the second catheter  150 . Furthermore, the package may also contain devices to facilitate delivery of the autoretroperfusion system  100  such as venous and arterial access devices, a delivery catheter, a guidewire and/or mandrel, an introducer to maintain the catheter  10  in the collapsed position during delivery and, in those embodiments where a coil is used to arterialize the vein of interest, a pusher bar as is known in the art. 
     The guidewire used to facilitate the delivery of the autoretroperfusion system  100  into a vessel by providing support to the components thereof. The guidewire may comprise any guidewire known in the art. Furthermore, the distal end of the guidewire may comprise a plurality of impedance electrodes that are capable of taking measurements of the size the vessel in which the guidewire is inserted through the use of impedance technology. Additionally, in at least one embodiment, the impedance electrodes may be further capable of communicating such measurements to the remote module  180  through telemetry or other wireless means in a manner similar to the at least one sensor  166  of the distal end  154  of the second catheter  150 . In at least one embodiment, the distal end of the guidewire may comprise two tetrapolar sets of impedance electrodes disposed on its distal-most tip. 
     Based on the information gathered by the impedance electrodes, a clinician can obtain accurate measurements of a selective region of a vessel. In this manner, the expandable balloon  158  coupled with the distal end  154  of the second catheter  150  may be properly sized and the amount of fluid or gas needed to inflate the expandable balloon  158  can be determined prior to introducing the second catheter  150  into the vein of interest. For example, a clinician can use the plurality of impedance electrodes on the guidewire to obtain measurements of the size and shape of the sub-branches of the coronary sinus. Details regarding the specifications and use of the impedance electrodes are described in detail in the currently pending U.S. patent application Ser. No. 10/782,149 entitled “System and Method for Measuring Cross-Sectional Areas and Pressure Gradients in Luminal Organs,” and filed on Feb. 19, 2004, which is hereby incorporated by reference herein in its entirety. 
     Now referring to  FIG. 5 , components of a simultaneous selective autoretroperfusion system  300  are shown. The simultaneous selective autoretroperfusion system  300  (the “SSA system  300 ”) are configured identically to the autoretroperfusion system  100  except that the SSA system  300  further comprises a third catheter  350  and a Y connector  320 , both configured for placement within the venous vessel wall  114 . Specifically, the SSA system  300  comprises the catheter  10 , the second catheter  150 , the third catheter  350 , the connector  170 , and the Y connector  320 . It will be understood that the SSA system  300  can also further comprise the first graft  185  and/or the second graft  190 , and the remote module  180  as described in connection with autoretroperfusion system  100 . 
     The third catheter  350  is configured for placement within the venous vessel wall  114  adjacent to the second catheter  150 . The third catheter  350  is configured identically to the second catheter  150  and comprises a flexible tube having a proximal end  352 , a distal end  354  and at least one lumen  356  extending between the proximal end  352  and the distal end  354 . Both the proximal end  352  and the distal end  354  of the third catheter  350  are open and in communication with the at least one lumen  356  of the third catheter  350 , thereby allowing blood to flow into the at least one lumen  356  through the proximal end  352  and out of the distal end  354  back into the venous vessel  114 . 
     The third catheter  350  may be any catheter known in the art that is capable of intravascular insertion and advancement through the venous system. The third catheter  350  may comprise any appropriate material, including without limitation, polyurethane or silicone rubber. In at least one embodiment, the third catheter  350  is configured to receive a guidewire  310  (see  FIGS. 5 and 6 ) through the at least one lumen  356  in order to facilitate the intravascular delivery of the distal end  354  of the third catheter  350  into the desired location of the venous vessel  114 . Furthermore, the third catheter  350  is coated with heparin or any other suitable anti-coagulant prior to insertion in order to facilitate the extended placement of the third catheter  350  within the venous vessel  114 . 
     As shown in  FIG. 5 , the distal end  354  of the third catheter  350  further comprises an expandable balloon  358  coupled with the external surface of the third catheter  350 . In operation, the expandable balloon  358  can be used to anchor the distal end  354  of the third catheter  350  in the desired location within the venous vessel wall  114 . The expandable balloon  358  may be any expandable balloon that is appropriate for insertion within a vessel and can be formed of any material suitable for this function, including without limitation, polyethylene, latex, polyestherurethane, polyurethane, sylastic, silicone rubber, or combinations thereof. 
     Similar to the expandable balloon  158  of the second catheter  150 , the expandable balloon  358  is capable of being controlled by a clinician such that it can inflate and/or deflate to the proper size. The appropriate size of the expandable balloon  358  can be determined through any technique known in the art, including without limitation, by measuring the compliance of the expandable balloon  358  ex vivo or in vivo. Furthermore, when the guidewire  310  is used to facilitate the delivery of the distal end  354  of the third catheter  350  into the desired location within the venous vessel wall  114 , the electrodes on the distal end of the guidewire  310  may be used to accurately measure the cross-sectional area of the venous vessel  114  such that the expandable balloon  358  can be precisely sized prior to insertion into the vein  114 . 
     In this at least one embodiment, the expandable balloon  358  is in fluid communication with a secondary lumen  360  disposed within the at least one lumen  356  of the third catheter  350 . In this example, the secondary lumen  360  is coupled with a balloon port  362  that extends from the proximal end  352  of the third catheter  350 . Accordingly, when the SSA system  300  is positioned within a patient, the balloon port  362  can be easily accessed by a clinician, subcutaneously, percutaneously or otherwise, and used to inflate or deflate the expandable balloon  358  with no or minimal invasion to the patient. 
     Similar to the second catheter  150 , the distal end  354  of the third catheter  350  may further comprise at least one sensor  366  coupled therewith. The at least one sensor  366  may be configured identically to the at least one sensor  166  of the second catheter  150  and, accordingly, the at least one sensor  366  may be used to monitor the pressure of blood flow through the at least one lumen  356  of the third catheter  350  or the venous vessel  114  or to monitor the pH or the concentrations of carbon dioxide, lactate, or cardiac enzymes within the blood. Furthermore, the at least one sensor  366  is capable of communicating the data it gathers to the remote module  180  through the use of a wireless technology such that a clinician can easily access the gathered information on a real-time basis or otherwise. In at least one embodiment, the at least one sensor  366  is disposed on the distal end  354  of the third catheter  350  distally of the expandable balloon  358 ; however, it will be understood that the at least one sensor  366  may be disposed in any location on the distal end  354  of the third catheter  350 . 
     The Y connector  320  of the SSA system  300  comprises flexible material and has a proximal end  322 , a distal end  324  and at least one lumen  326  extending between the proximal and distal ends  322 ,  324 . The proximal end  322  of the Y connector  322  is open and configured to be securely coupled with the graft  190 . The distal end  324  of the Y connector  322  comprises two open ends which extend from the body of the Y connector  322  in a substantially Y-shaped configuration. The two open ends of the distal end  324  of the Y connector  322  thereby divide the at least one lumen  326  into two separate channels and thus the blood flowing through the at least one lumen  326  is yet again bifurcated. 
     The proximal end  152  of the second catheter  150  is coupled with one of the two open ends of the distal end  324  of the Y connector  322 , thereby receiving a portion of the blood flow that flows through the at least one lumen  326  of the Y-connector. Similarly, the proximal end  352  of the third catheter  350  is coupled with the other open end of the distal end  324  of the Y connector  322  and, thus, the third catheter receives a portion of the blood flow that flows through the at least one lumen  326  of the Y-connector. In this manner, the SSA system  300  can be used to simultaneously retroperfuse more than one ischemic area of the body. 
     In application, the second catheter  150  and the third catheter  350  are positioned adjacent to each other within the venous vessel wall  114  as shown in  FIG. 5 . Furthermore, the distal ends  154 ,  354  of the second and third catheters  150 ,  350 , respectively, may be placed within different veins such that the arterial blood is delivered to selective portions of ischemic tissue. For example, as shown in  FIG. 6 , in at least one embodiment the SSA system  300  can be applied to a heart  314  to provide an arterial blood supply to two separate coronary veins, or sub-branches, simultaneously. In this at least one embodiment, the distal ends  154 ,  354  of the second and third catheters  150 ,  350  are both advanced through the coronary sinus  370 . As the diameter of the coronary sinus  370  ranges from about 10 to about 20 millimeters, cannulating the coronary sinus  370  with both the second and third catheters  150 ,  350  does not occlude the normal antegrade flow of the blood therethrough. Upon reaching the veins or sub-branches of interest, the distal ends  154 ,  354  of the second and third catheters  150 ,  350  are each independently positioned within the veins of interest. In the example shown in  FIG. 6 , the second catheter  150  is positioned within the interventricular vein  374  and the distal end  354  of the third catheter  350  is positioned within the middle cardiac vein  376 . As with autoretroperfusion system  100 , the expandable balloons  158 ,  358  are inflated through balloon ports  162 ,  362 , respectively (shown in  FIG. 5 ), such that the distal ends  154 ,  354  of the second and third catheters  150 ,  350  are securely anchored in the desired location within the veins of interest. In this manner, the SSA system  300  can deliver controlled arterial blood flow to, and thus arterialize, two areas of the heart  314  simultaneously. 
     In at least one embodiment of the SSA system  300 , the components of the system  300  are available in a package. Here, the package may also contain sterile syringes with the fluids to be injected into the balloon ports  162 ,  362  to inflate the expandable balloons  158 ,  358 , respectively. Furthermore, the package may also contain devices to facilitate delivery of the SSA system  300  such as arterial and venous access devices, a delivery catheter, at least two guidewires (configured as described in connection with the delivery of autoretroperfusion system  100 ), an introducer to maintain the catheter  10  in the collapsed position during delivery and, in those embodiments where a coil is used to arterialize the vein of interest, a pusher bar as is known in the art. 
     Now referring to  FIG. 7 , a flow chart of a method  400  for performing automatic retroperfusion using the system  100  is shown. While the method  400  is described herein in connection with treating a heart through catheterization of the coronary sinus, it will be understood that the method  400  may be used to perform autoretroperfusion on any organ or tissue in need of retroperfusion treatment and/or other areas near the coronary sinus, such as the great cardiac vein, for example. 
     Method  400 , and the embodiments thereof, can be performed under local anesthesia and do not require any arterial sutures. Further, once implanted, the system  100  can deliver chronic treatment to the patient as the system  100  is capable of remaining within a patient&#39;s vascular system for an extended period of time. In this manner, the system  100  and method  400  can be used to treat no-option patients and greatly enhance their quality of life. 
     As shown in  FIG. 7 , in one approach to the method  400 , at step  402  an artery  502  of interest is percutaneously punctured under local anesthesia with a conventional artery access device or as otherwise known in the art. For example and without limitation, in at least one embodiment, an 18 gauge needle is inserted into the femoral or subclavian artery. At step  404 , the catheter  10  housed in a collapsed position within an introducer  504  (see  FIG. 8A ) is inserted into the artery  502  of interest. After the distal end  14  of the catheter  10  is positioned in the desired location within the artery  502 , the introducer  504  is proximally withdrawn from the artery  502  as shown in  FIG. 8B , leaving the catheter  10  positioned therein. 
     In at least one embodiment, the projection cannula  16  is configured such that when the introducer  504  is withdrawn in a proximal direction, the proximal end  12  of the catheter  10  is released from the introducer  504  before the proximal end  20  of the projection cannula  16  is released from the introducer  504 . In this manner, the proximal end  12  of the catheter  10  is delivered within the interior of the arterial wall  502 , while the projection cannula  16  remains housed within the interior of the introducer  504  as shown in  FIG. 8C . Furthermore, because the introducer  504  no longer applies downward pressure to the projection cannula  16  relative to the proximal end  12  of the catheter  10 , the projection cannula  16  is allowed to shift from the collapsed position to the expanded position and therefore extends in a direction that is not parallel with the artery  502  or the body of the catheter  10 . In this manner, as shown in  FIGS. 8C and 8D , the proximal end  20  of the projection cannula  16  is directed through the opening formed in the arterial wall  502  by the introducer  504 . 
     Accordingly, when the catheter  10  is positioned within the artery  502 , the antegrade blood arterial blood flow is allowed to continue through the artery  502  through the proximal end  12  of the catheter  10 , while only a portion of the arterial blood is rerouted through the projection cannula  16  and into the veins  506  of interest. In this manner, the normal blood flow through the artery  502  is not inhibited by operation of the autoretroperfusion system  100 . Furthermore, in addition to bifurcating the blood flowing through the artery  502 , the projection cannula  16  traversing the arterial wall  502  further functions to anchor the catheter  10  in the desired position within the artery  502 . 
     In the embodiment where the catheter  10  further comprises the expandable balloon  58  (see  FIG. 1 ), step  404  may further comprise inflating the expandable balloon  58  to the desired size by injecting fluid into the balloon port  62 . In this manner, the expandable balloon  58  functions to further anchor the catheter  10  in the desired location within the artery  502  and seal the opening in the artery  502  through which the projection cannula  16  projects (see  FIG. 8E ). 
     At step  406 , a vein  506  of interest is percutaneously punctured under local anesthesia with a conventional venous access device or as otherwise known in the art. For example and without limitation, in at least one embodiment, an 18 gauge needle is inserted into the femoral or subclavian vein. At step  408 , a delivery catheter  508  is inserted into and advanced through the vein  506  to catheterize the coronary sinus ostium. A guidewire  510  is then inserted at step  410  into the delivery catheter  510  and advanced into the lumen of the vein  506  through the distal end of the delivery catheter  510 . Furthermore, the guidewire  510  is advanced into the region of interest by use of x-ray (i.e. fluoroscopy), direct vision, transesophageal echocardiogram, or other suitable means or visualization techniques. 
       FIGS. 9 and 10  show schematic views of the method  400  as applied to a heart  500 . Specifically, in this at least one embodiment, at steps  402  and  404  the artery  502 , which in  FIG. 9  comprises the subclavian artery, is punctured and the catheter  10  is inserted and positioned therein. Further, at step  406  the vein  506 , which in  FIG. 9  comprises the subclavian vein, is punctured and at step  408  the delivery catheter  508  is advanced through the superior vena cava  518  and into the coronary ostium of the coronary sinus  520 . As shown in  FIG. 10 , at step  410 , the guidewire  510  is advanced through the coronary sinus  520  and into the vein of interest, which, in this at least one embodiment, comprises the posterior vein  522  of the heart  500 . 
     Now referring back to  FIG. 7 , the guidewire  510  inserted into the vein  506  at step  410  may further comprise a plurality of impedance electrodes as previously described herein. In this approach, the guidewire  510  may be used at optional step  411  to determine the size of the vessel of interest through use of the plurality of impedance electrodes disposed thereon. In this manner, a clinician can use the measurements generated by the impedance electrodes to select a properly sized expandable balloon  158  for use in connection with the second catheter  150 . By using a precisely sized expandable balloon  158  and inflation volume, the clinician can ensure that the distal end  154  of the second catheter  150  is securely anchored within the vessel of interest without imposing an undue force on the venous vessel walls. 
     After the guidewire  510  has been advanced into the vessel of interest at step  410  and, optionally, the dimensions of the vessel of interest have been measured at step  411 , the method  400  advances to step  412 . At step  412 , the distal end  154  of the second catheter  150  is inserted into the delivery catheter  508  over the guidewire  510 . Accordingly, the guidewire  510  is slidably received by the at least one lumen  156  of the second catheter  150 . The distal end  154  of the second catheter  150  is then advanced over the guidewire  510  to the region of interest and the expandable balloon  158  of the second catheter  150  is inflated to anchor the distal end  154  within the targeted vessel.  FIG. 11  shows a schematic view of the method  400 , as applied to the heart  500 , after step  412  has been completed. It will be understood that at any point after the distal end  154  of the second catheter  150  is positioned and anchored within the desired location in the targeted vessel, the delivery catheter  508  and the guidewire  510  may be withdrawn from the vein of interest. 
     After the distal end  154  of the second catheter  150  is secured within the targeted vessel, at step  414  the anastomosis between the vein  506  and the artery  502  is formed. Specifically, in at least one approach, the proximal end  20  of the projection cannula  16  of the catheter  10  is coupled with the proximal end  152  of the second catheter  150  by way of the connector  170 . In the at least one embodiment of the system  100  comprising the first graft  185  and the second graft  190 , the connector  170  may be coupled with the catheter  10  and the second catheter  150  via the first graft  185  and the second graft  190  to form an elongated anastomosis. Alternatively, in yet another approach, the connector  185  may be coupled with the catheter  10  via the proximal end  20  of the projection cannula  16  and the second catheter  150  via only the second graft  190 . It will be understood that any combination of the catheter  10 , the second catheter  150  and the first and second grafts  185 ,  190  may be used in connection with the connector  170  to form the desired anastomosis between the vein  506  and the artery  502 . 
     After the anastomosis is formed and the arterial blood is allowed to flow through the anastomosis and thereby through the connector  170 , at step  416  the connector  170  measures the flow rate, pressure and any other desired data of the arterial blood flow. The connector  170  transmits the collected data to the remote module  180  either through intravascularly placed leads or wirelessly, through telemetry or other means. In this manner, a clinician may easily view the blood flow data on the remote module  180  and assess the degree of pressure drop that will be required to preserve and gradually arterialize the vein  506 . 
     At step  418 , the pressure of the arterial blood flow through the system  100  is modified to transmit the desired pressure to the venous system. In this step  418  the pressure modification can be achieved through a clinician modifying the means of regulating the blood flow of the connector  170  through remote means or, in at least one embodiment of the system  100 , inflating the internal expandable balloon of the second catheter  150  using the internal balloon port in order to partially occlude the flow of arterial blood through the at least one lumen  156  of the second catheter  150 . Furthermore, in at least one alternative embodiment of the system  100 , a clinician may deliver a resorbable stenosis configured to achieve the necessary pressure drop into the at least one lumen  156  of the second catheter  150  through means known in the art. 
     Alternatively, as previously described in connection with autoretroperfusion system  100 , the remote module  180  may further comprise a computer or other processing means capable of being programmed to automatically analyze the data received from the connector  170  and, based on such data, determine the proper degree of adjustment required in the blood pressure flowing through the anastomosis. In this embodiment, at step  418 , the remote module  180  automatically adjusts the means of regulating the blood flow of the connector  170  to achieve the optimal pressure drop. In this manner, the desired pressure drop between the arterial system and the venous system is immediately achieved and the risk of venous rupture is significantly reduced. 
     In step  420  the method  400  allows the arterial blood having a modified pressure to irrigate the vein  506  for a period of time such that the vein  506  properly arterializes. For example, and without limitation, the patient&#39;s venous system may be subjected to the reduced arterial pressure for about fourteen days to allow the vein  506  to adapt to the elevated blood pressure flowing therethrough. 
     After arterialization of the vein  506  is achieved, at step  422  the patient may optionally undergo a coronary venous bypass graft surgery and the components of the autoretroperfusion system  100  may be removed. However, as previously discussed, even with a properly arterialized vein  506 , many patients that require retroperfusion therapy may still not be candidates for a coronary vein bypass graft surgery. In the event that the patient is unable to tolerate such a procedure, after the vein  506  has arterialized at step  420 , the method  400  can progress directly to step  424 . At step  424 , the pressure modification of the arterial blood flowing through the second catheter  150  is ceased. Accordingly, pre-arterialized veins  506  are subjected to the full arterial pressure of the blood flowing through the anastomosis and second catheter  150 . In at least one embodiment, a clinician can cease the pressure modification by adjusting the controller  170 . Alternatively, in the at least one embodiment where the controller  170  can be automatically adjusted by the remote module  180 , the remote module  180  can automatically adjust the controller  170  after the veins  506  have pre-arterialized. Further, where the pressure drop is achieved through the use of an internal expandable balloon positioned within the at least one lumen  156  of the second catheter, the clinician may deflate the internal expandable balloon through the internal balloon port and thereafter withdraw the deflated internal expandable balloon through the tertiary lumen of the second catheter and the internal balloon port. In yet another embodiment where a resorbable stenosis is used to achieve the pressure drop in the arterial blood as it flows through the second catheter  150 , the resorbable stenosis can be configured to dissolve after the desired period of time, thereby gradually decreasing the influence the resorbable stenosis has on the pressure of the blood flowing through the at least one lumen  156  of the second catheter over a period of time. Accordingly, the autoretroperfusion system  100  can remain chronically implanted within the patient to deliver oxygen-rich blood to a targeted area of tissue over an extended period of time. 
     Now referring to  FIG. 12 , a flow chart of a method  600  for performing simultaneous selective retroperfusion using the SSA system  300  is shown. While the method  600  is described herein in connection with treating a heart  500  through catheterization of the coronary sinus  520 , it will be understood that the method  600  may be used to perform autoretroperfusion on any organ or tissue in need of retroperfusion treatment. The reference numerals used to identify the steps of method  600  that are included in the description of method  400  designate like steps between the two methods  400 ,  600 . As such, like steps between the two methods  400 ,  600  will not be discussed in detail with respect to the method  600  and it will be understood that such description can be obtained through the description of the method  400 . 
     Method  600 , and the embodiments thereof, can be performed under local anesthesia and does not require arterial sutures. Further, once implanted, the SSA system  300  can deliver simultaneous chronic treatment to multiple ischemic locations as the system  300  is capable of remaining within a patient&#39;s vascular system for an extended period of time and selectively retroperfusion more than one sub-branch of a vein  506 . 
     The method  600  progresses through steps  402  through  410  as previously described in connection with the method  400 . After the guidewire  510  is advanced through the coronary sinus  520  and into the first vein of interest, a second guidewire  610  is inserted at step  602  into the delivery catheter  508  adjacent to the guidewire  510 , and advanced into the lumen of the vein  506  through the distal end of the delivery catheter  510 . The second guidewire  610  is then advanced into a second region of interest by use of x-ray (i.e. fluoroscopy), direct vision, transesophageal echocardiogram, or other suitable means or visualization techniques. The second guidewire  610  is configured similar to the guidewire  510  and is capable of functioning the in the same manner. 
       FIG. 13  shows a schematic view of the method  600  as applied to a heart  500 . Specifically, in this at least one embodiment,  FIG. 13  shows the method  600  at step  602  wherein the guidewire  510  is inserted a first vein of interest, which comprises the posterior vein  522  of the heart  500 , and the second guidewire  610  is inserted into a second vein of interest, which comprises the interventricular vein  622  of the heart  500 . 
     Now referring back to  FIG. 12 , the guidewire  610  inserted into the second vein of interest in step  602  may further comprise a plurality of impedance electrodes as previously described with respect to the guidewire  510 . In this embodiment, the guidewire  610  may be used at optional step  603  to determine the size of the second vessel of interest through use of the plurality of impedance electrodes disposed thereon. In this manner, a clinician can use the measurements generated by the impedance electrodes to select a properly sized expandable balloon  358  for use in connection with the third catheter  350 . By using a precisely sized expandable balloon  358  and inflation volume, a clinician can ensure that the distal end  354  of the third catheter  350  is securely anchored within the second vessel of interest without imposing an undue force on the venous vessel walls. 
     After the guidewire  610  has been advanced into the second vessel of interest at step  602  and, optionally, the dimensions of the second vessel of interest have been measured at step  603 , the method  600  advances to step  412  wherein the second catheter  150  is inserted over the guidewire  510  as described in connection with method  400 . At step  604 , the distal end  354  of the third catheter  350  is inserted into the delivery catheter  508  over the second guidewire  610 . Accordingly, the second guidewire  610  is slidably received by the at least one lumen  356  of the third catheter  350 . The distal end  354  of the third catheter  350  is then advanced over the second guidewire  610  to the second region of interest and the expandable balloon  358  of the third catheter  350  is inflated to anchor the distal end  354  within the targeted vessel.  FIG. 14  shows a schematic view of the method  600  at step  604  as applied to the heart  500 . It will be understood that at any point after the distal ends  154 ,  354  of the second and third catheters  150 ,  350  are positioned and anchored in the desired locations within the targeted vessels, the delivery catheter  508  and the guidewires  510 ,  610  may be withdrawn from the vein  506 . 
     After both the distal end  154  of the second catheter  150  and the distal end  354  of the third catheter  350  are secured within the targeted vessels, the method  600  proceeds to step  414  where the anastomosis is formed between the vein  506  and the artery  502  as described in connection with method  400 . Thereafter, the method  600  advances through steps  416  through  424  as described in connection with the method  400 . Furthermore, at step  418 , it will be recognized that a clinician can independently adjust the pressure drop through the second and third catheters  150 ,  350  in the event that an internal expandable balloon is used in either or both catheters  150 ,  350  or resorbable stenosis are employed within the at least one lumens  156 ,  356  of the second and third catheters  150 ,  350 . Alternatively, in the at least one embodiment where the controller  170  comprises a means for regulating the blood flow through the anastomosis, the pressure of the arterial blood flowing through both the second and third catheters  150 ,  350  may be substantially the same. 
     As described herein, the method  600  may be used to simultaneously and immediately treat two different ischemic areas of a tissue through the use of one minimally to non-invasive procedure. Furthermore, the method  600  can provide no-option patients with a viable treatment option that is not associated with contraindications for congestive heart failure, diabetes, or drug treatment. 
     An additional embodiment of a perfusion system  100  of the present disclosure is shown in  FIG. 15 . As shown in  FIG. 15 , system  100  comprises a first catheter  1000  having a distal end  1002 , a proximal end  1004 , and defining a lumen  1006  therethrough, wherein at least a portion of first catheter  1000  is configured for insertion into a body of a patient, such as into a patient&#39;s heart or a patient&#39;s vein, for example. First catheter  1000 , after insertion into a patient&#39;s vein or heart, for example, is capable of providing arterial blood (which is relatively rich in oxygen and other nutrients) thereto by way of transfer of arterial blood from, for example, a patient&#39;s artery, as described below, into a proximal catheter opening  1008 , through lumen  1006 , and out of distal catheter opening  1010 . In such a fashion, for example, a system  100  can be referred to as an autoretroperfusion system  100 , noting that no outside pumps are necessary (as the patient&#39;s own heart serves as the pump), and due to the retrograde nature of the perfusion with respect to such a use. Exemplary uses, as provided in detail herein, are to provide arterial blood, using system  100 , to a patient&#39;s femoral vein, internal jugular vein, subclavian vein, and/or brachial cephalic vein. In an exemplary embodiment, first catheter  1000  may be tapered toward distal end  1002  to facilitate insertion into a patient. 
     In at least one embodiment of system  100 , and as shown in  FIGS. 15 and 16 , system  100  comprises a coupler  1012  having an outlet port  1013  and one or more additional ports to facilitate connection outside of the patient&#39;s body. For example, and as shown in  FIGS. 15 and 16 , coupler  1012  comprises an inflation port  1014 , whereby fluid and/or gas introduced into inflation port  1014  can be used to inflate an expandable balloon  1016  positioned along first catheter  1000  at or near the distal end  1004  of first catheter  1000 . As shown in the figures, and in at least one embodiment, an inflation tube  1018  may be coupled to inflation port  1014  at a distal end  1020  of inflation tube  1018 , whereby inflation tube  1018  may also have an optional flow regulator  1022  positioned relative thereto to regulate the flow and/or pressure of fluid and/or gas in and out of a lumen  1024  of inflation tube  1018  to inflate and deflate expandable balloon  1016 . Inflation tube  1018  may further comprise a proximal connector  1026  configured to receive fluid and/or gas from a fluid/gas source (not shown), whereby proximal connector  1026  can be positioned at or near a proximal end  1028  of inflation tube  1018 , for example. Inflation of expandable balloon  1016 , for example, can be used to anchor first catheter  1000  to a desired position within a luminal organ of a patient. 
     An exemplary coupler  1012  of the present disclosure further comprises an arterial blood port  1030  configured to receive arterial/oxygenated blood from, for example, an arterial blood tube  1032  coupled thereto at or near a distal end  1034  of arterial blood tube  1032 . As shown in  FIGS. 15 and 16 , a blood flow regulator  1036  may be positioned relative to arterial blood tube  1032  and operate to regulate the flow and/or pressure of arterial/oxygenated blood flow therethrough. In at least one embodiment, blood flow regulator  1036  comprises a rotatable dial capable of rotation to apply and/or remove pressure to/from arterial blood tube  1032  to regulate the flow and/or pressure of blood through a lumen  1038  of arterial blood tube  1032  and/or to adjust pressure therein based upon identified blood pressure measurements. Such a blood flow regulator  1036 , for example, can be used to control blood pressure to limit injury to the patient&#39;s luminal organs (such as the patient&#39;s venous system and/or myocardium) and/or to minimize potential edema with respect to the same luminal organs. Arterial blood tube  1032  may further comprise a proximal connector  1040  configured to receive arterial/oxygenated blood from a blood supply, whereby proximal connector can be positioned at or near a proximal end  1040  of arterial blood tube  1032 , for example. A coupler catheter  1042 , as shown in the component block diagram of system  100  shown in  FIG. 17 , may be used to couple arterial blood tube  1032  to a blood supply  1044 , which, as described herein, could be a patient&#39;s own artery using the patient&#39;s heart as a pump, or could be an external supply that provides blood to arterial blood tube  1032 , which may then be used in connection with an apparatus to remove blood from the patient as well. 
     Furthermore, and in at least one embodiment, an exemplary coupler  1012  of the present disclosure further comprises a medicament port  1046  configured to receive a medicament, saline, and/or the like, so that the same can enter the patient by way of first catheter  1000 . Medicament port  1046 , as shown in  FIGS. 15 and 16 , may receive a medicament tube  1048  defining a lumen  1050  therethrough, whereby a distal end  1052  of medicament tube  1048  can couple to medicament port  1046  so that a medicament, saline, and/or the like can be introduced from a medicament source (not shown) coupled to medicament tube  1052  at or near a proximal end  1054  of medicament tube  1048 . Exemplary medicaments may include, but are not limited to, fibrinolitic drugs, cardiotonic drugs, antirrhytmic drugs, scavengers, cells or angiogenic growth factors, for example, through the coronary vein or another luminal organ. In at least one embodiment, and as shown in  FIGS. 15 and 16 , medicament tube  1048  can be branched, whereby a second proximal end  1056  of medicament tube  1048  can receive a medicament and control the flow of medicament therethrough, for example, by way of a medicament regulator  1058  positioned relative to medicament tube  1048 , for example. Furthermore, one or more of proximal end  1054  and second proximal end  1056  may be configured to receive a wire therein, such as, for example, a 0.035″ guidewire and/or a 0.014″ pressure wire. As generally referenced herein, any blood, air, fluid, medicament, wire, etc. that enters coupler  1012  by way of inflation port  1014 , arterial blood port  1030 , and/or medicament port  1046  and eventually enters a lumen of first catheter  1000  will enter one or more of said ports of coupler  1012  and exit outlet port  1013  at the time of entry into first catheter  1000 . 
       FIG. 17 , as referenced above, is a block diagram of various components of an exemplary system  100  of the present disclosure. As shown therein, an exemplary embodiment of a system  100  of the present disclosure comprises a first catheter  1000 , a coupler  1012 , an arterial blood tube  1032  with a blood flow regulator  1036 , and a coupler catheter  1042  configured to for connection to a blood supply  1044 , wherein the blood supply may or may not be considered as part of a formal system  100 . In addition, an exemplary system  100  may comprise an inflation tube  1018  with a flow regulator  1022 , whereby an end of inflation tube  1018  is configured for connection to a gas/liquid source  1060 . Various embodiments of systems  100  of the present disclosure may have more or less components than shown in  FIG. 17 , and exemplary embodiments of systems  100  of the present disclosure may be configured to engage various embodiments of catheters  10  as referenced herein. 
     In use, for example, first catheter  1000  of system  100  may be positioned within a luminal organ of a patient within the patient&#39;s venous system. Inflation of expandable balloon  1016  to secure first catheter  1000  can not only provide oxygenated arterial blood to the patient&#39;s venous system, but can also continue to allow coronary venous return to continue due to the selective autoretroperfusion nature of an exemplary embodiment of system  100  and use thereof and due to the redundancy of the patient&#39;s venous system. In the event that an increased pressure, edema, or other undesired condition may occur at or near the site of inflated expandable balloon  1016 , a user of system  100  could, if desired, temporarily deflate expandable balloon  1016  to allow the increased pressure and or edema to alleviate itself. For example, system  100  could be used for a relatively long period of time (an hour, by way of example), and expandable balloon  1016  could be deflated for a relatively short period of time (seconds, for example), to alleviate a high pressure or edema occurrence, and then expandable balloon  1016  could be re-inflated to again secure first catheter  1000  at a desired location within the patient. 
     The type of patients for whom the device will be utilized in the acute application may fall into various categories, including, but not limited to, S-T segment Elevated Myocardial Infarction (STEMI) patients, cardiogenic shock patients, and high risk Percutaneous Coronary Intervention (PCI) patients (such as those undergoing PCI of the left main coronary artery). STEMI is the traditional “emergent” patient who presents with classic heart attack symptoms, and when diagnosed in a hospital emergency room for example, the patient would traditionally be immediately moved to a Cath Lab to receive PCI to open an occluded coronary artery and restore blood flow to the myocardium. These patients are hemodynamically unstable and need support for the left ventricle. 
     In such a use, for example, an exemplary system  100  of the present disclosure could be used to, for example: 
     (i) provide cardiac support to a patient who does not have immediate access to the Cath Lab and PCI. These patients may present in rural or community hospitals that do not have Cath Labs. They will need some type of temporary support while being transferred to an appropriate facility. These patients might also present at a hospital with a Cath Lab, but the Cath Lab is either understaffed to treat the patient, or does not have an available room to treat. In these cases, the system  100  of the present disclosure operates as a bridge to provide support until definitive treatment (primary PCI) is available; and/or 
     (ii) provide cardiac support before, during, and after primary PCI. Many patients enter the Cath Lab in an unstable condition, and the insertion of balloons and stents adds to hemodynamic instability. An exemplary system  100  can provide cardiac support and improve hemodynamics such that the physician can operate in a more stable/controlled environment. It is also believed that by reperfusing ischemic myocardium before/during/and after primary PCI, one may reduce the amount of myocardium that is damaged by the ischemic event. This is clinically referred to as a “reduction in infarct size.” Initial animal studies (as referenced in further detail herein) have suggested that the use of SARP in support of STEMI patients could cause a reduction in infarct size, which would have a significant impact on the outcomes for the patient in both the near and long term. Reduction in infarct size would slow the progression of any subsequent heart failure and reduce long term hospitalization and costs for this group of patients. 
     Cardiogenic shock is marked by a significant lowering of blood pressure and cardiac output that if not reversed, will ultimately lead to multisystem organ failure and death. Cardiogenic shock patients have a mortality exceeding 60%. In many cases, cardiogenic shock patients are too unstable to undergo surgery or PCI. Pharmacologics are used to increase pressure and cardiac output. Intra Aortic Balloon Pumps (IABP) and other LVAD type products are also employed to improve hemodynamics in an attempt to reverse the downward cycle of cardiogenic shock patients Exemplary embodiments of systems  100  of the present disclosure could be used in much the same fashion. 
     High Risk PCI is typically defined as patients who have disease of the left main coronary artery, are diabetic, have multivessel disease, are above 75 years of age, have a prior history of MI, have renal insufficiency, etc. These are very sick patients, who are considered at high risk of adverse events before, during, and after undergoing PCI. Mortality rates and Major Adverse Cardiac Event (MACE) rates are much higher in this patient population. IABP&#39;s are commonly used in this patient population. 
     In this population, systems  100  of the present disclosure may be used to provide cardiac support for a high risk PCI patient who is, at the time of the procedure, found to be hemodynamically unstable. It is evident to the operator that cardiac support is and will be needed during the procedure, and an exemplary system  100  of the present disclosure would be deployed from the outset. The patient&#39;s hemodynamics improve and the operator feels more comfortable working in the coronary system. IABP use is common in these patients. 
     Systems  100  of the present disclosure may also be used in this high risk population when it is anticipated that cardiac support may be needed during the procedure. In this case, an exemplary system  100  is deployed prior to the case, in order to provide support when and if it is needed. The patient is hemodynamically stable at the outset, and remains so throughout. IABP&#39;s are currently used in this fashion. This is commonly referred to as prophylactic use of cardiac support. 
     Acute Applications: 
     In this setting, exemplary systems  100  of the present disclosure will be used for cardiac support and to protect myocardium for a period of time that will generally be less than 24 hours. The clinical condition that precipitated the need for SARP will have typically been resolved in that 24 hour period, and the system  100  would be removed. However, use of systems  100  of the present disclosure are not limited to a 24 hour period, as in some cases, IABPs and other short term cardiac support devices are left in for periods exceeding 24 hours. Typically, the longest period of time that a short term device might be left in place is 4-6 days, at which point the clinician would begin to consider longer term implanted Left Ventricular Assist Devices (LVADs), which can support a patient for an extended period of time (weeks), and are often used as a bridge to heart transplant. 
     Clinical conditions that would require the acute application of an exemplary system  100  of the present disclosure include, but are not limited to: 
     (i) Emergent treatment of STEMI and/or other Acute Myocardial Infarction (AMI) patients; 
     (ii) Cardiogenic shock; 
     (iii) High Risk PCI; 
     (iv) Failed or aborted PCI where severe hemodynamic instability presents after initiation of the procedure. These patients are often transferred to immediate cardiac surgery, and require cardiac support while waiting for the surgical intervention; and/or 
     (v) Weaning from a cardiopulmonary bypass machine in cardiac surgery. Some cardiac surgery patients have difficulty returning to normal cardiac condition when the cardiopulmonary bypass machine is turned off and the heart is restarted after successful revascularization in cardiac surgery. Exemplary systems  100  of the present disclosure could be used to support the heart until normal cardiac parameters return. Insertion could occur in the surgical suite, and the device would be left in place while the patient was transferred to a Cardiac Critical Care Unit (CCU). 
     These exemplary clinical conditions cover the majority of potential applications for an acute embodiment of a system  100  of the present disclosure. Currently, more than 95% of all IABP and other short term support devices are used for these applications. 
     In such applications, the goal of using an exemplary system  100  of the present disclosure is to deliver arterial (oxygenated) blood to the myocardium, in a retrograde manner using the venous system, in order to create hemodynamic stability for the patient and to protect and preserve myocardial tissue until the clinical event resolves or primary intervention (PCI or CABG) and revascularization can occur. 
     Chronic Applications: 
     In this setting it is intended that an exemplary embodiment of a system  100  of the present disclosure be implanted for 2 weeks or longer, for example, noting that ultimate implantation may be somewhat shorter in duration. Initial animal studies suggest that within 2 weeks, arterialization of the venous system is achieved, such that the venous system can become the conduit for a constant flow of arterial blood at arterial pressure. 
     A clinical condition where the chronic application of a system  100  would be utilized is often referred to as “no option” patients, that is, patients for which there are no options available through which their clinical condition can be resolved. More specifically, these are patients with diffuse coronary artery disease (CAD) or refractory angina, where PCI and/or Coronary Artery Bypass Graft Surgery (CABG) is not an option. Patients that are diabetic, or have other co-morbidities, and are not candidates for interventions, would be candidates for a chronic application of a system  100  of the present disclosure. 
     As previously referenced herein, the chronic application will generally require 10-14 days of retroperfusion in order to allow arterialization of the venous system. In certain instances, retroperfusion could be required for a longer period (such as 2-3 weeks, for example), or a lesser period, such as less than 10 days, for example. These patients, dependent upon their complete clinical situation, may be hospitalized for that period, or they may reside outside of the hospital. When residing outside of the hospital, the device utilized may be a catheter  10  embodiment with a branched implantable portion, such as shown in  FIG. 1 , for example. The catheter  10 , including method of pressure regulation, would be implanted in the patient. 
     For those chronic patients, who must remain in the hospital for one of the aforementioned time periods, an acute embodiment of a system  100 , for example, may be applicable. In such an embodiment, for example, system  100  may be percutaneously inserted and utilized during that time frame. Once arterialization occurs, a more permanent conduit may be constructed percutaneously or surgically to provide the permanent arterial blood source. 
     When using an exemplary system  100  of the present disclosure, standard guide catheters can be used by the clinician to locate the coronary sinus and/or the great cardiac vein, for example. An 0.035″ guidewire can be inserted to further establish access to the coronary sinus or the great cardiac vein. An exemplary system  100  can then be inserted over the 0.035″ guidewire and advanced to the coronary sinus or the great cardiac vein, for example, via one of the ports as referenced herein. 
     The distal end  1004  of the first catheter  1000  is intended to be located at the left main vein. The operator may advance the tip (distal end  1014 ) of first catheter  1000  to other vein sites dependent on clinical need. A balloon  1016 , which in at least one embodiment may be located approximately 2 cm back from the distal end  1004 , would then be inflated to secure the position of first catheter  1000  within the coronary sinus or the great cardiac vein, for example, allowing for the distal end  1004  of first catheter  1000  to locate at the left main vein. The inflated balloon  1016  will also work to ensure that arterial blood will flow in the retrograde fashion. 
     Once the distal balloon  1016  is inflated, the 0.035″ guidewire can be exchanged for an 0.014″ pressure measurement wire, which will be used to measure the pressure at the distal end  1004  of first catheter  1000 , to ensure that the portions of system  100  are not over pressurizing the vein, and to tell the operator how much pressure change will be required from the external pressure regulator. The proximal end of the pressure wire will be connected to its appropriate monitor. 
     When the catheter is located in the coronary sinus or the great cardiac vein, for example, the operator can now make the external (outside the body) connection to the arterial blood supply  1044 . This is typically, but not limited to, the femoral or radial arteries. The physician will have previously inserted a standard procedural sheath into the arterial source in order to gain access to the source. This arterial sheath can also be used to provide access for catheters, guidewires, balloons, stents, or other devices that might be utilized while treating the patient. That arterial sheath will have a connector which can connect to the arterial supply cannula (with regulator) on the acute device (an embodiment of system  100 ). Once the connection is established and flow commences, the pressure wire will indicate the distal pressure measurement and the regulator can be adjusted to the proper setting (not to exceed 60 mmhg, for example). Monitoring of the distal pressure will be on-going throughout the period of time that the device is in-vivo. The regulator allows the operator to provide the correct distal pressures and to adjust those pressures, dependent on changes in the patient&#39;s pressure. 
     With the pressure set and monitored, the patient is now receiving oxygenated blood to the myocardium in a retrograde fashion thru the coronary venous system. Such an operation (namely to retrogradly provide oxygenated blood) can be used to save a significant amount of ischemic tissue at the level of the border zone. In at least one embodiment, such a system  100  is used to perfuse the left anterior descending vein to supply oxygenated blood to the LAD artery occluded territory. Depending upon patient need and circumstance, the acute device (an embodiment of system  100 ) will be removed typically within the first 24 hours of insertion. The physician will make that determination. The insertion site will be closed per hospital protocol. 
     Validation of Methodology 
     As referenced in detail herein, coronary artery disease (CAD) is the number one cause of morbidity and mortality in the U.S. and worldwide. Even today, with percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG), optimal and timely treatment is still not available for all patients. Bridge therapies to complement existing gold standards of reperfusion therapy would be of significant value to a large number of patients. 
     Because the coronary venous system rarely develops atherosclerosis, the use of the venous system for delivery of oxygenated blood has been well explored. Synchronized retrograde perfusion (SRP) and pressure-controlled intermittent coronary sinus occlusion (PICSO) are two retroperfusion methods for acute treatment of myocardial ischemia through the coronary venous system. PICSO and SRP have been used in conjunction with a balloon-tipped catheter positioned just beyond the orifice of the coronary sinus connected to a pneumatic pump, and either passively redirect coronary sinus blood (PICSO) or actively pump arterial blood during diastole (SRP) to the ischemic myocardium. These techniques have been shown to decrease ischemic changes, infarct size, myocardial hemorrhage, and no-reflow phenomenon, and improve left ventricular (LV) function when coronary blood flow is reinstituted after an acute occlusion. Wide application of these techniques, however, has been limited by concerns over their safety and complexity, and in particular, the need for repeated occlusion of the coronary sinus with a balloon. High pressure (SRP and PICSO) and flow (SRP) can cause damage to the coronary sinus with thrombosis and chronic myocardial edema. 
     We have validated in animal studies both the acute and chronic application of the methodologies referenced herein. In a recent acute study, we showed that preservation of the contractile function of the ischemic myocardium can be accomplished with selective autoretroperfusion (SARP) without the use of an external pump during acute LAD artery ligation. The hypothesis that SARP can preserve myocardial function at regulated pressures without hemorrhage of vessels or damage of myocytes was verified. In connection with this animal work, a bolus of Heparin was given before instrumentation and was then supplemented as needed to keep an activated clotting time (ACT) over 200 seconds. The right femoral artery was cannulated with a 7Fr catheter and connected to a pressure transducer (TSD104A—Biopac Systems, Inc) for monitoring of arterial pressure. Before the sternotomy, the right carotid artery was cannulated with a 10Fr polyethylene catheter through a ventrolateral incision on the neck to reach the brachiocephalic artery to supply the LAD vein during retroperfusion. The catheter had a roller clamp that was used to control the arterial pressure transmitted to the LAD vein. The right jugular vein was cannulated with an 8Fr catheter for administration of drugs and fluids. Lidocaine hydrochloride was infused at a rate of 60 μg/kg/min before opening the chest and during the rest of the procedure. Magnesium sulfate (10 mg/min IV) along with lidocain was also used to treat extrasystole in the case of the control group. A vasopressor (Levophed®, Norepinephrine Bitartrate Injection, Minneapolis, Minn., 2-6 μg/min IV) was used during the procedure, and was adjusted accordingly to maintain a constant arterial blood pressure (70.0±8.9 mmHg, mean) in both the experimental and the control groups. Finally, heparin and nitroglycerine were diluted in 60 mL of 0.9% sodium chloride and infused using a syringe pump at a rate of 1 ml/min. The chest was opened through a midsternal thoracotomy, and an incision was made in the pericardium with the creation of a sling to support the heart with pericardial stay sutures. 
     A pair of piezoelectric ultrasonic crystals (2 mm in diameter on 34 gauge copper wire—Sonometrics Corporation) were implanted through small stab incisions in the anterior wall of the LV (area at risk) distal to the planned site (below first diagonal branch in the SARP group, and second diagonal branch in the control group) of LAD artery ligation, for assessment of regional myocardial function through measurement of midwall segment length changes. An additional pair of crystals was also implanted in the anterior wall of the LV within the normal perfusion bed (control area) of the proximal portion of the LAD artery. 
       FIG. 18  shows a schematic of the retroperfusion system showing the arterial and retroperfusion catheters. Each pair of crystals were positioned in the midmyocardium (about 7 mm from the epicardium) approximately 10-15 mm apart and oriented parallel to the minor axis of the heart. The acoustical signal of the crystals was verified by an oscilloscope. 
     In the SARP group (ligation+retroperfusion) the LAD artery was dissected free from the surrounding tissue distal to the first diagonal branch for subsequent ligation. A 2.5 mm flow probe was placed around the LAD artery and connected to a flow meter (T403—Transonic Systems, Inc). The LAD vein was also dissected close to the junction with the great cardiac vein, and the proximal portion ligated with 2-0 silk suture in order to prevent runoff to the coronary sinus. The LAD vein was then cannulated below the ligation with a 10Fr cannula that was attached to the brachiocephalic catheter through one of two four-way stopcocks. A flow probe was placed between the stopcocks for measurement of coronary venous flow. Venous pressure was recorded through the pressure monitoring line from the retroperfusion cannula (as shown in  FIG. 18 ). Retroperfusion was initiated immediately after ligation of the LAD artery and was maintained for a period of 3 hours. Arterial blood samples were taken at baseline and at the end of the first, second and third hours of ligation+retroperfusion for monitoring of pH, hematocrit, electrolytes, activated clotting time, and cardiac troponin I. 
     Coronary venous SARP may be an effective method of protecting the myocardium during acute ischemia before definitive treatment is established as referenced herein regarding various catheter  10  and system  100  embodiments of the present disclosure. SARP may not only offer protection to the ischemic myocardium through retrograde perfusion of oxygenated blood but may also serve as a route for administration of thrombolytics, antiarrhythmics, and cell and gene therapy to the jeopardized myocardium before PTCA or CABG can be implemented in patients eligible for these procedures. 
     In addition to the foregoing, various devices and systems of the present disclosure can be used to perform methods for retroperfusion of various bodily organs to treat many different types of conditions. As referenced above, providing blood from one bodily vessel to another bodily vessel can be performed using devices and systems of the present disclosure, but in accordance with the following, said devices and systems can also be used to perform the following novel methods and procedures. 
     As generally referenced above, the concept of using veins to deliver oxygenated nutrient-filled blood (arterial blood) is predicated on the fact that despite any extent of the coronary arterial disease, the corresponding venous counterpart is atherosclerosis-free. An additional fact is that the upper body arterial system has much less predilection for atherosclerosis than the lower body. As such, the present disclosure identifies that the upper body can generally serve as the source of arterial blood to the venous systems of organs with arterial disease, and that devices and systems of the present disclosure can also be used in that regard. 
     An additional characteristic of the venous system necessary to facilitate SARP (as referenced herein) is the existence of a redundancy of the venous system (namely multiple veins per artery as well as interconnections between venous vessels) to ensure proper venous drainage when portion of the system is used for SARP. 
     In view of the foregoing, a number of embodiments for retroperfusion of various organs or bodily regions that identify arterial blood donor and organ (venous system) are identified with the present disclosure, including, but not limited to, the following: 
     (i). Peripheral vessels. Embodiments of devices and systems of the present disclosure can be used to provide oxygenated blood from the femoral artery, the internal femoral artery, or the iliac artery, for example, to the distal saphenous vein or to deep muscle veins for arterialization in diabetic patients (a diffuse disease) to treat, for example a leg pre-amputation or a necrotic or gangrenous foot ulcer. This venous system has valves (typically larger than 1-1.5 mm in diameter) which can be overcome (inverted) through catheterization (namely the insertion of guidewire and SARP catheter, with guidewire dimensions down to 0.35 mm for 0.014″ standard guidewire) to facilitate said peripheral vessel treatment. 
     (ii). Kidney-Renal Vein. Embodiments of devices and systems of the present disclosure can also be used to facilitate arterialization of the renal vein, which can be partial (polar vein) or total (left or right main veins) by way of the femoral or iliac arteries (if disease free), or from the axillary, brachial, or subclavian arteries of the upper body, if desired. Said procedure could be performed to, for example, treat acute or chronic renal ischemia due to diffuse atherosclerosis, severe intima hyperplasia, and to treat the kidney in connection with various collagen-vascular diseases. 
     (iii). Intestine (Bowel). A number of arterial sources, such as the femoral, iliac, axiallary, brachial, subclavian, or epigastric arteries, can be used with devices and systems of the present disclosure to facilitate regional arterialization following vein anastomosis (at the vein arch) to treat mesenteric arterial ischemia. In at least one embodiment, said arterialization is performed to treat an acute embolic or thrombotic mesenteric artery occlusion in patients with a severe bowel ischemia. 
     (iv). Spine. The first of the two main divisions of the spinal system, namely the intracranial veins, includes the cortical veins, the dural sinuses, the cavernous sinuses, and the ophthalmic veins. The second main division, namely the vertebral venous system (VVS), includes the vertebral venous plexuses which course along the entire length of the spine. The intracranial veins richly anastomose with the VVS in the suboccipital region, and caudally, the cerebrospinal venous system (CSVS) freely communicates with the sacral and pelvic veins and the prostatic venous plexus. The CSVS constitutes a unique, large-capacity, valve-less venous network in which flow is bidirectional. The CSVS plays important roles in the regulation of intracranial pressure with changes in posture, and in venous outflow from the brain. In addition, the CSVS provides a direct vascular route for the spread of a tumor, an infection, or an emboli among its different components in either direction. Various embodiments of devices and systems of the present disclosure can be used to provide oxygenated blood from the external carotid artery, the brachial artery, or the axiallary artery, directly to the jugular vein to treat any number of potential spinal injuries or conditions, including spinal cord ischemia. 
     (v). Penis. Various embodiments of devices and systems of the present disclosure can also be used to provide arterial blood from the epigastric artery to the penile dorsal vein to the cavernous system of the penis to treat erectile dysfunction. 
     The foregoing examples of organ-specific perfusion protocols are not intended to be exhaustive, but merely exemplary of various novel uses of perfusion devices and systems of the present disclosure. Accordingly, the present disclosure includes various methods for treating organ-related diseases, various methods of providing arterial (oxygenated) blood to veins at or near various organs, and various methods of potentially arterializing veins at or near various bodily organs using devices and systems of the present disclosure. 
     For example, and as shown in  FIG. 19 , an exemplary method of organ perfusion of the present disclosure is provided. Method  1900 , in at least one embodiment, comprises the steps of positioning at least a portion of a device into a patient&#39;s artery (an exemplary artery positioning step  1902 ), positioning at least a portion of the same or a different device into a patient&#39;s vein at or near a target organ (an exemplary vein positioning step  1904 ), and facilitating operation of the positioned portions to allow blood to flow from the artery to the vein to treat a condition or disease of the target organ (an exemplary operation step  1906 ). 
     By way of example, an exemplary artery positioning step  1902  could be performed by positioning at least part of a first catheter  10  having a cannula  16  within an artery of a patient, the first catheter  10  configured to permit arterial blood to flow therethrough and further configured to permit a portion of the arterial blood to flow through the cannula  16 , and an exemplary vein positioning step  1904  could be performed by positioning at least part of a second catheter  150  within a vein of the patient at or near a target organ, the second catheter  150  configured to receive some or all of the portion of the arterial blood. In such an embodiment, which may be referred to as a chronic treatment using catheter  10  and catheter  150 , an exemplary operation step  1906  involves connecting the cannula  16  of the first catheter  10  to a portion of the second catheter  150  so that some or all of the portion of the arterial blood flowing through the cannula  16  is provided into the vein to treat a condition or disease of the target organ. 
     Further, and by way of another example, an exemplary artery positioning step  1902  could be performed by positioning at least a portion of an arterial tube  1032  of a perfusion system  100  within an artery of a patient, the arterial tube  1032  configured to permit arterial blood to flow therethrough, and an exemplary vein positioning step  1904  could be performed by positioning at least a portion of a first catheter  1000  of the perfusion system  100  into a vein of the patient at or near a target organ, the first catheter  1000  configured to receive some or all of the arterial blood from the arterial tube  1032 . In such an embodiment, which may be referred to as an acute treatment using system  100  of the present disclosure, an exemplary operation step  1906  involves operating a first flow regulator  1036  of the perfusion system  100  so that some or all of the arterial blood flowing through the arterial tube  1032  is provided into the vein to treat a condition or disease of the target organ. 
     In addition to the foregoing, an exemplary device for occluding a luminal organ of the present disclosure is shown in  FIG. 20 . As shown in  FIG. 20 , device  2000  comprises a coil  2002  configured to fit within a delivery mechanism  2004 , such as a delivery catheter. Coil  2002 , in various embodiments, has at least two configurations, namely an uncompressed (or expanded) configuration and a compressed (or retracted) configuration, as shown in  FIGS. 20 and 21 , respectively. As referenced herein, the terms “uncompressed” and “expanded” are used interchangeably, and the terms “compressed” and “retracted” are used interchangeably. Delivery mechanism  2004 , as shown in  FIG. 20 , is configured to fit within a mammalian luminal organ  2006 , such as a vein, for use in connection with an arterialization procedure, for example. Furthermore, and in various embodiments, device  2000  comprises a non-coil device  2000 , wherein the non-coil device  2000  has at least two configurations, namely an expanded configuration and a retracted configuration, wherein the retracted configuration is capable of occluding a patient&#39;s luminal organ. The expanded configuration of coil  2002 , as generally referenced above, would not occlude the luminal organ, while the retracted configuration of coil  2002 , as noted above, would occlude the luminal organ. 
     Delivery of coil  2002  to a targeted location within a bodily vessel may be facilitated by use of a pusher  2008 , as shown in  FIGS. 20 and 21 . Pusher  2008 , in various embodiments, comprises a shaft  2010  and an optional tip  2012  configured to fit within delivery mechanism  2004  and to facilitate placement of coil  2002 . Tip  2012 , as shown in  FIGS. 20 and 21 , may be relatively circular in shape so to prevent coil  2002  from moving past pusher  2008  within delivery mechanism  2004 . 
     Delivery mechanism  2004 , as referenced above and shown in  FIG. 20 , may comprise a catheter having a wall  2014  defining a lumen  2016  therethrough. Coil  2002 , in an expanded configuration, would fit within lumen  2016  of delivery mechanism  2004  during delivery of coil  2002  within a patient&#39;s body. 
     Coil  2002  may have any number of configurations. In at least one embodiment, coil  2002  has a first configuration that has a relatively linear configuration that is a native first configuration. In the present application, the term “native” refers to a configuration that coil  2002  has without any external assistance. For example, a native first configuration of coil  2002  may be relatively stretched, and a native second configuration of coil  2002  may be relatively compressed. While an external device, such as a pusher  2008 , may be used to facilitate conversion from a native first configuration to a native second configuration, coil  2002  would then remain in a second configuration without any external forces or pressures used to maintain the second configuration. Should a user of coil  2002  subsequently desire to convert coil  2002  back to a first configuration, external forces or pressures could be used to facilitate the conversion, and coil  2002  would then again natively remain in a first configuration  2002  until changed once again. 
       FIGS. 22A and 22B  show the delivery of a coil  2002  within a mammalian luminal organ, such as a cardiac vein. As shown in  FIG. 22A , delivery mechanism  2004 , coil  2002 , and pusher  2008  are advanced into luminal organ  2006 , and after being positioned in a desired location, coil  2002  can be delivered directly into luminal organ  2006 , as shown in  FIG. 22B , to occlude luminal organ  2006 . 
       FIG. 22C  shows the delivery of a coil within a patient&#39;s heart  2200 . As shown in  FIG. 22C , delivery mechanism  2004 , coil  2002 , and pusher  2008  are advanced into the patient&#39;s heart, through the coronary sinus  2202 , and into the cardiac vein, so that coil  2002  can be delivered within the cardiac vein to occlude the same. 
     In various embodiments, coils  2002  are metallic memory coils (comprising nitinol, stainless steel, and/or the like) having an optional coating  2020  (as shown in  FIG. 20 ) such as polytetrafluoroethylene (PTFE), polyethylene terephthalate (such as Dacron®, for example), polyurethane, and/or other biologically-compatible coatings. In at least one embodiment, coil  2002  is radiopaque so that it can be identified within a patient&#39;s body using radiography, for example. 
     An exemplary coil occlusion system of the present disclosure is shown in the block diagram of  FIG. 23 . As shown in  FIG. 23 , system  2300  comprises an exemplary occlusion device  2000  of the present disclosure, a delivery mechanism  2004 , and a pusher  2008 . Occlusion device  2000  and pusher  2008 , when delivering occlusion device  2000 , would be positioned within lumen  2016  of delivery mechanism  2004 . Prior to delivery of occlusion device  2000 , an optional guidewire  2302  can be introduced into a patient so that delivery mechanism  2004 , or a portion thereof, can be advanced over guidewire  2302  to facilitate the ultimate delivery of occlusion device  2000 . 
     An exemplary method of using an exemplary occlusion device  2000  of the present disclosure to occlude a luminal organ is described as follows and as shown in the block diagram of method steps shown in  FIG. 24 . In at least one embodiment of method  2400  of the present disclosure, method  2400  comprises the steps of introducing an exemplary occlusion device  2000  of the present disclosure into a patient&#39;s body (an exemplary introduction step  2402 ), which may be performed by advancing a delivery mechanism  2004  into a patient&#39;s body with our without the prior insertion of a guidewire  2302  to facilitate delivery. Method  2400 , as shown in  FIG. 24 , may then comprise the step of advancing at least part of delivery mechanism  2004  to a desired location within a patient (an exemplary delivery mechanism advancement step  2404 ), such as, for example, a patient&#39;s vein. In at least one embodiment, method  2400  comprises the step of advancing an occluder device  2000  positioned within delivery mechanism  2004  (an exemplary occluder device advancement step  2406 ) directly into the patient&#39;s luminal organ (outside of delivery mechanism) using, for example, pusher  2008 . Occluder device advancement step  2406  may itself also include the step of compressing occluder device  2000  or otherwise facilitating a configuration change from a first uncompressed or otherwise non-occlusive configuration to a second compressed or otherwise occlusive configuration (an exemplary compression step  2408 ), or compression step  2408  may be performed after occluder device advancement step  2406 . Compression step  2408  is performed so that occluder device  2000  effectively occludes the luminal organ percutaneously. After compression step  2408 , delivery mechanism  2004  and pusher  2008  may be withdrawn from the patient&#39;s body (an exemplary delivery mechanism withdrawal step  2410 ), whereby occluder device  2000  remains within a patient&#39;s luminal organ, occluding the same. 
     Performance of method  2400 , as referenced herein, may be in conjunction with a potential arterialization and/or retroperfusion method. Mammals (humans and animals) have a venous system comprising an excess number/amount of veins, i.e., drainage through the venous system can be made through any number of channels. Arterialization, a term generally used to describe a change of a part of a vein to a part of an artery, includes gradual thickening of the venous wall over time so that the arterialized vein can withstand the higher pressures of the arterial system if the arterialized vein were to be grafted into the arterial system. Subjecting a non-arterialized venous vessel to the high pressures of arterial blood flow typically results in rupture of the venous vessel. With certain corresponding retroperfusion therapies, for example, the pressure of the arterial blood flow is at least initially controlled such that the venous vessel can arterialize prior to being subjected to the unregulated pressure of the arterial blood flow. 
     Descriptions of arterialization and retroperfusion are referenced in other applications of Kassab, including PCT/US08/87863, filed Dec. 19, 2008, U.S. Ser. No. 13/125,512, filed Apr. 21, 2011, and U.S. Ser. No. 13/092,803, filed Apr. 22, 2011, the entire contents of which are hereby incorporated into the present disclosure by reference in their entirety. 
     In view of the same, an exemplary method  2400  may further include the steps of excising an arterialized vein from the patient&#39;s venous system (an exemplary excision step  2412 ) and grafting the arterialized vein into the patient&#39;s arterial system (an exemplary grafting step  2414 ), as shown in  FIG. 24 . Excision step  2412  would occur a period of time after occluder device  2000  has been positioned within a vein, as the increased pressure of the vein at or near the occlusion would promote vein arterialization. Excision step  2412  and grafting step  2414  may be performed in connection with a coronary bypass procedure, for example. An exemplary method  2400  may further comprise the general step of performing a retroperfusion procedure (as referenced in one or more of PCT/US08/87863, filed Dec. 19, 2008, U.S. Ser. No. 13/125,512, filed Apr. 21, 2011, and U.S. Ser. No. 13/092,803, filed Apr. 22, 2011) (an exemplary retroperfusion step  2416 ) during coil occlusion and/or after exemplary excision step  2412 . 
     While various embodiments of coil occlusion devices and systems and methods of using the same have been described in considerable detail herein, the embodiments are merely offered as non-limiting examples of the disclosure described herein. It will therefore be understood that various changes and modifications may be made, and equivalents may be substituted for elements thereof, without departing from the scope of the present disclosure. The present disclosure is not intended to be exhaustive or limiting with respect to the content thereof. 
     Further, in describing representative embodiments, the present disclosure may have presented a method and/or a 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 therein, the method or process should not be limited to the particular sequence of steps described, as other sequences of steps may be possible. Therefore, the particular order of the steps disclosed herein should not be construed as limitations of the present disclosure. In addition, disclosure directed to a method and/or process should not be limited to the performance of their steps in the order written. Such sequences may be varied and still remain within the scope of the present disclosure.