Abstract:
A device for performing a surgical procedure within a body and a method for utilizing such a device to treat a patient&#39;s heart with minimal invasiveness. The device comprises a handle, a guide shaft, and a sleeve in slideable connection with the guide shaft. The guide shaft is connected to the handle at a proximal portion and has a first curved position at the distal portion. Slideable manipulation of the sleeve changes the first curved position. The method comprises providing such a device, introducing the device into a minimally invasive port in the patient, and providing treatment to the patient&#39;s heart.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This utility patent application claims priority to Provisional Patent Application Ser. No. 60/650,911 entitled SURGICAL APPARATUS HAVING CONFIGURABLE PORTIONS which was filed on Feb. 8, 2005. 
     
    
     STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT  
       [0002]     Not Applicable  
       BACKGROUND  
       [0003]     The present invention relates to the field of surgery, and, more particularly to surgical procedures and apparatus for use with minimally invasive ports.  
         [0004]     Medical science has developed a wide variety of surgical devices for assessing different areas of the body and for performing various surgical procedures. Many of these surgical devices and procedures require a relatively large opening within the patient&#39;s body just to gain access into the body cavity and to the desired area of treatment. This is particularly true with surgical devices having broad shapes and configurations and when used in conjunction with procedures requiring large movements of the device or requiring multiple treatment locations. Improvements are continuously being sought to reduce the negative effects of any surgery, including the effects incurred when penetrating the body with surgical devices and further when accessing the treatment areas. This concern has lead to the desire to reduce such effect and further to utilize minimally invasive procedures wherever possible.  
         [0005]     In minimally invasive surgical procedures, the trauma to the body is reduced, in part, by reducing the surgical opening required into the body cavity. Thus, there is a great desire to modify existing open surgical devices for application with minimally invasive procedures and ports.  
         [0006]     Transmyocardial revascularization (“TMR”) is a procedure wherein energy is delivered to a region of the heart in order to create channels across the wall of the heart. The procedure is typically performed in patients suffering from severe angina. TMR is performed in a surgical setting in which access to the left ventricle is typically gained through an open surgical sternotomy or a thoracotomy. With the advent of minimally invasive thoracoscopic surgical procedures in recent years, it is desirable to deliver TMR therapy minimally invasively via ports. Present TMR surgical devices, however, require unique configurations that generally preclude the use of such minimally invasive ports.  
       BRIEF SUMMARY  
       [0007]     The present invention comprises a surgical device for treating living tissue within a body. The device includes a handle portion for gripping and manipulation by the surgeon or other user. An elongated tubular guide shaft is connected to the distal handle portion and extends outwardly into a distal portion having a curved shape. The distal end of the guide shaft includes a head assembly that is adapted for forming a contact surface with a desired region of the heart and includes a treatment assembly that is adapted for the desired treatment. The device includes an advancement mechanism to move the treatment assembly relative to the head assembly. The advancement mechanism allows the treatment assembly to be translated along the distal portion of the guide shaft so as to translate outwardly from the head assembly and also to be retracted.  
         [0008]     A tubular guide shaft straightening assembly is slideably connected to the guide shaft wherein translation of the straightening assembly along the guide shaft elongates the curved distal portion of the guide shaft and straightens out the curved shape of the guide shaft. Retracting the straightening assembly allows the guide shaft to return to a curved shape.  
         [0009]     The present invention further comprises a minimally invasive procedure for treating a patient&#39;s heart. The method comprises the steps of providing an elongated surgical device having a guide shaft extending away from a handle portion into a curved distal portion and including a treatment assembly. A sleeve assembly is slideably mounted over the guide shaft and configured such that when the sleeve is extended along the guide shaft and away from the handle the curved distal portion of the guide shaft is elongated along the axis of the guide shaft and the curvature reduced or eliminated such that the guide shaft is aligned along a single axis. The curvature of the guide shaft is reformed when the sleeve is retracted towards the handle.  
         [0010]     In the procedure, the sleeve is first slid outwardly along the guide shaft from a normally retracted position so as to reduce the curvature of the distal portion and straighten out the entire length of the guide shaft. The guide shaft is then introduced into a minimally invasive port in the patient. Once the elongated guide shaft is positioned within the patient, the sleeve may be retracted relative to the guide shaft, returning the distal portion into a curved configuration for treating the heart. This step, including extending and retracting the sleeve, may be repeated during the procedure so as to reconfigure the guide shaft whenever desired. The treatment assembly is then manipulated into position adjacent the heart such that the desired region of the heart or associated tissue may be treated.  
         [0011]     The present invention further comprises a system and method of surgical myocardial revascularization of the myocardium of the heart of a patient. In this procedure, a surgical opening and preferably a minimally invasive port is created within the patient. An elongated flexible surgical apparatus configured into an insertion configuration is inserted into the surgical opening and directed into the chest cavity. The surgical apparatus preferably includes a lasing mechanism in connection with a surgical lasing tip located at the distal end of a flexible guide shaft. The guide shaft, including the lasing tip is then guided within the patient and into a desired area within the chest cavity. The elongated guide shaft portion of the surgical apparatus may be adjusted and configured between a straightened shaft configuration and a configuration having a curved distal portion so as to facilitate advancement and positioning within the patient. By manipulating a sleeve on the apparatus, the guide shaft can be reconfigured from an essentially straight configuration into a curved configuration having an essentially ninety degree curvature or anywhere in between. In addition, the guide shaft, including the attached surgical end may be rotated to further assist in the advancement and positioning of the surgical end adjacent the regions of the heart to be treated. The heart is next irradiated with laser energy emitted from the lasing apparatus with sufficient energy and for a sufficient time to cause a channel to be formed from the exterior surface of the epicardium through the myocardium and the epicardium. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]     These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which:  
         [0013]      FIG. 1  is a side view of an embodiment of the surgical device of the present invention.  
         [0014]      FIG. 2A  is a side view of a preferred embodiment of the surgical device of the present invention with the straightening sleeve removed.  
         [0015]      FIG. 2B  is a top view of an embodiment of the surgical device of the present invention with the sleeve removed and having an enlarged cup.  
         [0016]      FIG. 2C  is a side view of an embodiment of the surgical device of the present invention with the sleeve removed and having an enlarged cup.  
         [0017]      FIG. 2D  is a bottom view of an embodiment of the surgical device of the present invention with the sleeve removed and having an enlarged cup.  
         [0018]      FIG. 3  is a side view of a preferred embodiment of the surgical device of the present invention showing the straightening sleeve in a retracted position.  
         [0019]      FIG. 4  is a side view of a preferred embodiment of the surgical device of the present invention showing the straightening sleeve in the extended position. 
     
    
     DETAILED DESCRIPTION  
       [0020]     While a variety of embodiments of the present invention are disclosed herein, one exemplary and the presently preferred embodiment of the surgical device is illustrated generally as reference number  10  in  FIGS. 1-4 . This embodiment of the surgical device  10  is particularly suitable for procedures for treating the heart, including transmyocardial revascularization, biopsy and related procedures. The device  10  is adapted for hand use and manipulation and may be held in several positions or with both hands.  
         [0021]     A preferred method using the device  10  of the present embodiment involves using a treatment assembly associated with the device to perforate the epicardium of the heart to create myocardial revascularization pathways. Such pathways are typically revascularization channels which extend into myocardium and may or may not communicate with the ventricle.  
         [0022]     Referring now to  FIG. 1 , the preferred mechanical surgical device  10  includes a hand piece  12  which is a housing molded or machined from a plastic material, and defining a contoured surface  14  defining one or more finger grip indentations. Preferably, the contoured surface  14  provides tactile feedback regarding the position of the hand on the device so the physician need not look away from the medical procedure or other task at hand. The contoured surface  14  further assists the user to securely hold the hand piece without slippage in at least two, different positions during either left or right handed operation of the device  10 . A neck portion or nosecone  16  extends from the hand piece  12  and is preferably a separate component to allow for a rotary connection with the hand piece. The nosecone  16  may also be constructed from a molded or machined plastic or similar to the hand piece  12 , may be constructed from other materials such as metal or composite materials. The hand piece  12  and nosecone  16  include a continuous passageway for supporting a treatment assembly  18  which in a preferred TMR procedure includes an optical fiber bundle whose proximal end is connected to a laser energy source (not shown). In the preferred embodiment, the treatment assembly is moveable within the apparatus passageway using a mechanical finger slide configured as part of the handle portion  12  but may also be moveable using most any form of mechanical, electro mechanical slide mechanism or may even be moved using an automated mechanism.  
         [0023]     A tubular guide shaft  20  extends outwardly from a proximal portion connected to the nosecone  16  of the handle  12  into a distal curved portion  22 . The proximal portion of the guide shaft  20  may be constructed of metal, plastic or composite materials and may be slightly malleable to allow some flexibility. Preferably, the proximal portion of the guide shaft is made from a medical grade tubular stainless steel and the distal curved portion from a flexible plastic with memory. The guide shaft  20  includes a lumen having an opening or diameter sufficient to allow passage of the desired treatment apparatus  18 . The guide shaft  20  is rigidly attached to the nosecone  16  and may be rotated about the axis “A” by twisting or otherwise rotating the nosecone relative to the handle portion  12 .  
         [0024]     As shown, the guide shaft  20  extends away from the handle  12  to the distal portion  22  having a curved shape of approximately 90 degrees from the axis “A”. The curved distal portion  22  of the guide shaft  20  terminates at distal end  24  which is connected to a protective and stabilizing tip assembly  26 . The stabilizing tip  26  is generally ball, cup or disc shaped and is designed to contact tissue and maintain contact of the device  10  on the region of tissue being treated. The stabilizing tip  26  may be constructed from generally yieldable materials such as silicone, soft elastic, rubber or foam and may also be metallic or plastic. The stabilizing tip  26  may be part of or permanently attached to the shaft  20  or may be detachable with conventional snap-mount or screw mount mechanisms. Different detachable stabilizing tips  26 , such as suction and drug delivery tips, may be provided to accommodate different treatment procedures as well as differing access ports. The distal end or tissue contacting surface of the tip  26  may be textured to provide a gripping surface, and suction may be provided at the proximal end of the hand piece to extend through the shaft  20  to further secure the stabilizing tip  26  to the tissue being treated, including the heart. The stabilizing tip  26  includes a bore aligned and in connection with the bore formed through the guide shaft  20 . In this way, the treatment assembly  18  may freely pass through the guide shaft  20  and the cup tip  26 .  
         [0025]     In this preferred embodiment configured for TMR, the stabilizing tip  26  is a flexible cup having a proximal end with an outer diameter equivalent to the outer diameter of the distal end  24  of the guide shaft  20 . The proximal end of the cup  26  is rigidly bonded to the distal end  24  of the guide shaft  20  and may be configured with a proximal end diameter similar to that of the distal end  24  of the guide shaft  20 . The cup  26  tapers outwardly from the guide shaft  20  into a contact surface outer diameter of about 8 mm. The cup  26  is preferably made from a medical grade polyether block co-polyamide polymer (“Pebax”) or other medical grade nylon type material that is sufficiently pliable to form a contact surface with the tissue being treated and is bonded to the distal end  24  of the guide shaft  20 . Alternatively, the cup  26  and the curved portion  22  of the guide shaft  20  may be formed from a single piece of flexible plastic material such as Pebax. Alternatively, the guide shaft  20  and the cup  26  may be constructed from multiple segments of material having varying hardness. For example, a stiffer material may be used to create a stiffer, or more spring like curved portion  22  and a softer material may be used to create an atraumatic cup  26 .  
         [0026]     The present invention advantageously decreases the outer diameter of the tissue contacting surface of the cup  26  as compared to present configurations of TMR surgical devices. The smaller outer diameter facilitates access to difficult-to-reach areas of the heart when moving to a new location to create a channel. In addition, the smaller diameter facilitates use of the device  10  with smaller and minimally invasive ports. As designed, the smaller diameter cup still allows for sufficient stabilization and further ensures that the distal end of the treatment assembly contacts the treatment area at the desired angle. In the apparatus shown, the cup  26  is designed for proper stabilization against the epicardium and further ensures that the lasing treatment tip  30  contacts and enters the epicardium at an approximate perpendicular angle to the tissue surface.  
         [0027]     The curved portion  22  is configured to have and naturally retain a curvature of between 30 and 150 degrees and preferably about 90 degrees from the elongated axis of the guide shaft  20 . When the device  10  is provided with a rotatable neck portion  16 , the orientation of the curved portion  22  and the cup  26  may be altered by rotating the neck portion relative to the handle  12 . Rotation mechanisms between the neck portion  16  and the handle portion  12  may include conventional spring fingers, detents and ratchet assemblies or simply a friction fit. In addition, the neck portion  16  is provided with a configuration that facilitates gripping while rotating.  
         [0028]     Referring now to  FIGS. 2A-2D , the curved portion  22  of the guide shaft, in the preferred embodiment is made from a flexible plastic material such as a tubular section of Pebax. The Pebax curved portion  22  is bonded at a proximal end  28  to the generally straight proximal section of the guide shaft  20  and also bonded at its distal end  24  to the cup  26 . Other methods of securing the multiple sections of the guide shaft  20  may also be used. Alternatively, the entire guide shaft may be made from a singular piece of flexible material such as Pebax, other nylon, silicone, or most any other surgical grade material or combination of such materials. In addition, the guide shaft may be made from multiple segments, each having different qualities such as hardness, colorings and markings. For example, the guide shaft  20  may be made from materials having differing flexibility, elasticity as well as memory. This way, one can adjust the amount of force required to straighten out the curved portion  22  or even the amount of spring force the curved portion exerts to return to its curved shape when it is straightened out. Similarly, various colorings may be provided as positional locators along the length of the guide shaft. These colorings may be provided as differing materials or simply as external markings.  
         [0029]     In the preferred configuration described, the guide shaft  20  is about 22 centimeters long, including the proximal portion (straight section) made from a 304 stainless steel tubing of about 18.5 centimeters in length bonded to the curved section of Pebax tubing having an approximate length of 3.3 centimeters. The passageway extending through the surgical device  10  is adapted to allow for the passage of a treatment assembly  18 .  
         [0030]     In general, the curved portion  22  of the guide shaft  20  is specifically designed and adapted to be flexible between the curved shape  22  having an angle of about 90 degrees from axis “A” and an elongated straightened configuration wherein the curved portion is straight and generally aligned along axis “A”. Likewise, the portion of the treatment assembly  18  passing through the guide shaft is also configured to be flexible such that it can also transition between an essential 90 degree curve and a straight path.  
         [0031]     Referring now back to  FIGS. 1 and 3 , a straightening sleeve  32  is mounted about and coaxial with the guide shaft  20 . In the embodiment shown, the straightening sleeve  32  is a tube including a proximal portion  34  configured as a gripping section that is mounted over the shaft  20  adjacent the handle  12 . The gripping section  34  includes a bearing surface  36  along its inner diameter that contacts the guide shaft  20  to facilitate sliding of the sleeve  32  along the guide shaft  20 . Preferably, the bearing surface  36  also reduces lateral movement of the sleeve  32  relative to the guide shaft  20 . The gripping section  34  may also include a configuration that facilitates friction against the user&#39;s fingers while sliding the sleeve relative to the guide shaft  20 . In the embodiment shown, the gripping section  34  is formed of a plastic and has a larger outside diameter than the remainder of the sleeve  32 . In addition, the gripping section  34  includes several raised rings  38  aligned generally perpendicular to sleeve  32 . Alternatively, the sleeve  32  and the gripping section  34  may be constructed of almost any rigid material and may further include any configuration that facilitates a user&#39;s ability to slide the sleeve  32  relative to the guide shaft  20 .  
         [0032]     In a preferred embodiment, the integral straightening sleeve  32  is composed of a stainless steel tube connected to the tubular gripping section  34  at the proximal end. The sleeve  32  is coaxial with the guide shaft  20 . The sleeve  32  is slideable along the guide shaft  20  from a first sleeve position (retracted position) wherein the proximal end of the gripping section  32  is adjacent to the distal end of the neck portion  16  as illustrated in  FIGS. 1 and 3 . In the fully retracted position, the curved portion  22  is bent at approximately 90 degrees from the elongated axis “A” of the device  10 . The straightening sleeve  32  may also be made from various materials or multiple segments of materials and may even be fitted with a special distal end specifically configured for contacting and straightening the curved distal portion  22 . In addition, the sleeve  32  may be fitted with various devices to facilitate movement along the shaft  20 , such as bushings. The sleeve may also be fitted with a locator device, including a hole for identifying markings or colorings on the guide shaft  20 .  
         [0033]     Referring now to  FIG. 4 , the surgical device of the present invention is shown with the straightening sleeve  32  fully extended (extended position) relative to the guide shaft  20  such that the curved portion  22  of the guide shaft is straightened out and the entire guide shaft elongated along the axis “A”. When the sleeve  32  is extended, its distal end  40  is moved along the flexible curved portion  22  of the guide shaft  20  directing it into the sleeve without kinking or damaging it and without distortion of the interior bore defining the passageway through the device  10 . The sleeve distal end  40  may be formed into a smooth flanged outer edge to facilitate sliding along the curved portion  22  of the guide shaft and reduce distortion of the cup  26 . The sleeve distal end  40  may also be configured to accept the distal end  24  of the guide sleeve or even a treatment end  30 .  
         [0034]     The straightening sleeve  32  may also be tapered along its elongated axis such that it has a smaller interior diameter at its distal end  40  and retains a tighter fit around the curved portion  22  of the guide shaft  20 . A tapered sleeve  32  may reduce distortions to the cup  20  when moved into the extended position. Alternatively, sleeve distal end  40  may be fit with a flange that is specifically made to facilitate the curved portion  22  sliding into the sleeve  32  when extending the sleeve. Moving the sleeve  32  between the retracted position and the extended position, and there between, allows a user to modify the angle of the curved portion  22  from between a curved position of 90 degrees with the axis “A” and a straight guide shaft position.  
         [0035]     During a preferred TMR procedure using the surgical device  10  or the present invention, energy is applied to myocardial tissue of the heart by means of the treatment assembly  18  supported within the passageway extending through the hand piece  12  and further extending through the guide shaft  20  and out from the cup  26 . In the currently preferred procedure, a laser provides the energy that is directed through the treatment assembly  18  which includes a means of carrying the laser energy to the treatment tip  30 . In the preferred embodiment, a fiber optic cable is used.  
         [0036]     To facilitate a minimally invasive surgical procedure using the present surgical device  20 , including the use of 8 mm ports, the straightening sleeve  32  is moved along the guide shaft  20  towards the curved portion  22  so as to straighten out the curved distal portion. Preferably, the sleeve  32  is slid distally along the guide shaft  20  so that as it is slid over the curved portion  22 , the walls of the sleeve force the curved portion to be straightened out inside the sleeve itself. Once the curved portion  22  is straightened out, the guide shaft  20  may be inserted into a minimally invasive port within the patient.  
         [0037]     The physician can then manipulate the surgical device  10  and particularly, the guide shaft  20  within the patient. Once the user determines the guide shaft  20  is appropriately positioned, the straightening sleeve  32  may be retracted to increase the curvature of the distal portion  22  of the guide shaft. The user may retract the sleeve  32  sufficient to create the desired curvature  22 . Alternatively, the user may retract or extend the sleeve  32  to achieve any desired configuration (curvature) at multiple times during a procedure. In the preferred embodiment of the present invention, the bearing  36  maintains a sufficiently tight friction fit around the proximal portion of the guide shaft  20  so as to maintain its position relative to the guide shaft once it is released by the user.  
         [0038]     In a presently preferred TMR procedure, the guide shaft  20  is inserted into the chest cavity of a patient through an 8 mm port. If necessary, the guide shaft  20  may be adjusted from a straight configuration ( FIG. 4 ) into one having a curved configuration ( FIG. 3 ) so as to facilitate passage of the guide shaft within the patient or to facilitate positioning of the guide shaft adjacent the treatment area. Once positioned adjacent the epicardium, the user adjusts the treatment assembly  18  such that the treatment tip  30  is positioned perpendicular to the epicardium. It is often necessary to retract the sleeve  32  such that the curved portion  22  of the guide shaft  20  forms an approximately 90 degree angle ( FIG. 3 ) to create the desired perpendicular positioning of the treatment tip  30  with the epicardium wall. In addition, the nosecone  16  may also be used to rotate the cup  26  and treatment tip  18  as desired.  
         [0039]     Further details of the present invention, including various methods of using the present invention may be found with reference to the Detailed Description of Embodiment section of U.S. Pat. No. 5,713,894 issued on Feb. 3, 1998 to Murphy-Chutorian and Harman and to the Detailed Description of the Preferred Embodiment section of U.S. Pat. No. 5,976,164 issued on Nov. 2, 1999 to Bencini et al. of which both are incorporated in their entirety herein by reference.  
         [0040]     The foregoing describes the features and benefits of the present inventions in various embodiments. Those of skill in the art will appreciate that the present invention is capable of various other implementations and embodiments that operate in accordance with the foregoing principles and teachings. For example, many of the components may be made from various materials and may be interconnected in various ways. Moreover, the arrangement of an elongated guide shaft having a curved distal portion and a sliding sleeve mechanism for elongating the curved portion into a straight portion may be accomplished by using differing tubular shapes or even with a portion of or all of the straightening sleeve adjacent to the guide shaft rather than slideably mounted over and around it. The curved portion of the guide shaft may also be positioned proximally adjacent the hand piece or even mid section. The curved portion may be curved along three axes. The housing may be made of materials other than plastic and may be configured differently to provide alternative designs. Further, the various features of the embodiments disclosed herein can be used alone, or in varying combinations with each other and are not intended to be limited to the specific combination described herein. Accordingly, this detailed description is not intended to limit the scope of the present invention, which is to be understood by reference the claims below.