Abstract:
A device for intracavity stimulation of the left atrium and/or ventricle of the heart from the prepectoral region through a less invasive and lower-risk approach is provided that allows the implantation of an intracavity catheter in the left cardiac chambers through a femoral approach atrial transseptal puncture, and the removal of the catheter proximal end by the retrograde venous route.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Application Serial No. P 2007 01040682 filed in Argentina on Oct. 23, 2007, the disclosure of which is and incorporated by reference and commonly owned. 
     FIELD OF INVENTION 
     The invention generally relates to cardiac surgery and cardiac implantations, and more particularly to a device and method for intracavity stimulation of the left atrium and/or ventricle through a femoral approach atrial transseptal puncture and removal of the catheter proximal end by a retrograde venous route toward the prepectoral region. 
     BACKGROUND 
     Methods to insert catheters in left atrium and/or ventricles through surgery—an outer cut on the chest wall—, are well known and known to be a very sensitive and high-risk approach from a patients point of view and requires close post surgical control, or in the venous system of the heart, which method is often impossible to carry out and requires considerable expertise in performance, thus limiting general application. Currently, there exists an additional technique, which consists of intracavity stimulation of the left ventricle; however, it is complex and difficult to perform. 
     The insertion of catheters in right atrium and/or ventricles is currently performed in a simple way by inserting the catheter in the subclavian, cephalic or jugular vein after a simple puncture and by means of a catheter introducer. 
     However, this is not the case when the catheter is to be inserted in the left atrium and ventricle, because there is no direct path through the mentioned veins; as per the previous art, surgery is required in order to insert the catheter outside (the epicardial region) the atrium and/or the left ventricle, including a cut in the external chest wall, which procedure entails a great risk. On the other hand, this technique offers a very restricted access to the left atrium and ventricle, thus preventing the choice of the best implantation site. 
     There is the option to insert the catheter in the venous system of the heart, which is often impossible to perform due to the morphologic structure of the system, requiring considerable expertise in the technique and limiting its general application. 
     Another technique uses the transseptal puncture of the atrium to insert the catheter by the antegrade venous route. This technique requires multiple passing of sheaths, balloon catheters and lines through the interatrial septum, successive dilations of the interatrial septum, etc., which turn it complex and increase patients&#39; risk. 
     SUMMARY 
     The present invention is directed to solving the problems as addressed above and in one embodiment provides a device for placing the catheter into (intracavity implantation) the left atrium and/or ventricle using the venous system, that is, without external surgical openings, only by making a single puncture on the septum between the right and left atria, and removal of the catheter proximal end (the end that is connected to the pacemaker or any other device that might be implanted) in the prepectoral region by the retrograde venous route. 
     A desirable feature of the invention is its simplicity and safety, since the elements are inserted by simple venous and transseptal punctures. Methods do not require a chest opening for implantation. Devices used do not require use of the venous system of the heart. The catheter is inserted into the left atrium and/or ventricle by a single transseptal puncture on the interatrial septum of the heart. There is no need for additional dilations of the interatrial septum puncture. Embodiments of the invention do not require successive passing of elements through the interatrial septum and allows the choice from among several sites of the best site on each patient to implant the catheter in the left atrium and ventricle. Further, the surgical techniques required are commonly used and broadly known. 
     One embodiment of the invention provides for the implantation of an intracavity catheter in the left atrium and/or ventricle through a single femoral approach transseptal puncture on the atrium, and the removal of the proximal end of the catheter by the retrograde venous route toward the prepectoral region. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The advantages of this invention, which should not be limited to the brief description above, will become more apparent and the invention itself better understood by reference to the following embodiments of the invention herein described by way of example with reference to the accompanying annotated drawings in which: 
         FIG. 1  is a schematic view of the human body with the localization of the subclavian vein and the femoral vein, and their relation to the superior vena cava, the inferior vena cava and the right atrium of the heart. 
         FIG. 2  is a  2 - 2  sectional view of  FIG. 1  showing details of the cardiac chambers, and the superior vena cava and the inferior vena cava entry in the right atrium. 
         FIG. 3  is a longitudinal sectional view of a Fastener according to the teachings of the present invention, which is inserted by femoral route, showing the insertion site and the central passage. 
         FIG. 4  is a side view of a Pulling Element of this according to the teachings of the present invention, which is inserted by femoral route. 
         FIG. 5  is a longitudinal sectional view of a Runner according to the teachings of the present invention, which is inserted by femoral route, showing the central passage. 
         FIG. 6  is a side view of a Mandrel according to the teachings of the present invention, which is inserted by femoral route. 
         FIG. 7  is a side view of a Loop Catheter of this invention, which is inserted in the subclavian vein. 
         FIG. 8  is a side sectional view of a Cardiac Catheter of this invention, which is inserted by femoral route and removable by the subclavian, jugular or cephalic veins, showing the central passage. 
         FIG. 9  is a longitudinal sectional view of an Aligning device of this invention and its central passage, which is inserted in the subclavian vein. 
         FIG. 10  is a side sectional view of the Connector (the proximal End of the Cardiac Catheter) inserted in the Fastener, and the Pulling Element between them. 
         FIG. 11  is a detailed longitudinal sectional view of the Mandrel partially inserted in the Runner. 
         FIG. 12  is a detailed longitudinal sectional view of the same elements of  FIGS. 10 and 11 , now into the transseptal sheath. 
         FIG. 13  is an outline of the human body showing details of the position of the catheter introducers in the subclavian vein and the femoral vein, which are identified with arrows. 
         FIG. 14  is an outline of the human body showing details of the insertion of the Loop Catheter in the subclavian vein, and identifying with dotted lines the section in the superior vena cava, the right atrium of the heart, and the insertion and a short section in the inferior vena cava. 
         FIG. 15  is an outline of the human body showing details of the introduction of the transseptal sheath by femoral route until it reaches the right atrium of the heart as identified with dotted lines. 
         FIG. 16  represents an expansion circular of the  FIG. 15 , of the passing through the loop of the Loop Catheter in the inferior vena cava. 
         FIG. 17  is an outline of the human body showing details of the puncture performed on the interatrial septum of the heart using the Brockenbrough needle well-known method, as identified with dotted lines. 
         FIG. 18  is an outline of the human body showing the passage of the transseptal sheath to the left atrium, and the passage of the Cardiac Catheter having the Mandrel inside through the transseptal sheath, as identified with dotted lines. 
         FIG. 19  is a sectional view of  FIG. 1  showing details of the Cardiac Catheter having the Mandrel inside into the left atrium, and the transseptal sheath having been removed toward the inferior vena cava. 
         FIG. 20  is a  2 - 2  sectional view of  FIG. 1  showing details of the Mandrel partially removed toward the proximal end of the catheter. 
         FIG. 21  illustrates a circled expansion of the detail of the  FIG. 20 , showing details, identified with dotted lines, of the Loop Catheter and this inside into the transseptal sheath. 
         FIG. 22  is a sectional view of  FIG. 1  showing details of the Runner moving inside the transseptal sheath, as identified with a dotted line, and pushing the Fastener and the Pulling Element toward the right atrium of the heart. 
         FIG. 23  is an outline of the human body showing complete retrograde removal of the Mandrel by pulling it from the proximal end of the transseptal sheath, as identified with a dotted line. The removal of the Mandrel disassembles the Fastener from the Runner, leaving the latter free inside the transseptal sheath and the former free inside the inferior vena cava. 
         FIG. 24  is a sectional view of  FIG. 1 , showing details of the Loop Catheter retrograde pull of the Pulling element joined to the Fastener and the proximal end of the Cardiac Catheter, the transseptal sheath remaining inside the inferior vena cava and the detached Runner and the rest of the Pulling Element still remaining inside the transseptal sheath. 
         FIG. 25  is a  2 - 2  sectional view of  FIG. 1 , which has to be considered sequentially after the previous figure, showing details of the Loop ‘Catheter retrograde pull of the Pulling element joined to the Fastener and the proximal end of the Cardiac Catheter inside the superior vena cava (the direction being identified with arrows), and the transseptal sheath remaining inside the inferior vena cava; the transseptal sheath is later on removed retrogradely. 
         FIG. 26  is a  2 - 2  section view of  FIG. 1 , which has to be considered sequentially after the previous figure, showing details of the retrograde pull of the Fastener and the proximal End of the Cardiac Catheter by the Pulling Element into the superior vena cava. 
         FIG. 27  is a detailed sectional view of the subclavian vein and the superior vena cava with the inner part of the catheter introducer showing the insertion of the Aligning Element inserted in the Pulling Element moving into the catheter introducer in the subclavian vein, and the superior vena cava ready to receive the Fastener and the proximal end of the Cardiac Catheter through its outlet in order to facilitate its way out through the catheter introducer. 
         FIG. 28  is an outline of the human body showing details of the retrograde removal of the Fastener and the proximal end of the Cardiac Catheter through the catheter introducer, the localization of the other end of the Cardiac Catheter inside the superior vena cava and the left atrium or ventricle of the heart being identified with dotted lines. 
         FIG. 29  is an outline of the human body, which has to be considered sequentially after the previous figure, showing details of the final position of the proximal end of the Cardiac Catheter outside the human body, and a  2 - 2  sectional view of the  FIG. 1  showing details of the other end of the Cardiac Catheter inside the left atrial chamber, or passing through the mitral valve on different localizations in the left ventricle, as identified with dotted lines, and ready to connect the pacemaker. 
     
    
    
     In order to relate the drawings above to the following description, the parts or components shown in the different drawings have been identified with a common reference number. 
     DESCRIPTION OF EMBODIMENTS 
     One embodiment of the invention is herein described by way of example as a system and method for intracavity stimulation of the left atrium and/or ventricle through a femoral approach atrial transseptal puncture and removal of a catheter proximal end by a retrograde venous route toward the prepectoral region. The system includes a KIT the following components that are assembled: a Fastener  1  ( FIG. 3 ), a Pulling Element  2  ( FIG. 4 ), a Runner  3  ( FIG. 5 ), a Mandrel  4  ( FIG. 6 ), a Loop Catheter  5  ( FIG. 7 ), a Cardiac Catheter  6  with a Connector  7  at its proximal end ( FIG. 8 ) and an Aligning device  8  ( FIG. 9 ). 
     Before using the elements of this invention, a puncture as needed to insert the catheter introducer in the subclavian vein  10  is performed on the patient ( FIG. 13 , as identified with an arrow). 
     The Loop Catheter  5  of this invention is passed along the catheter introducer in the subclavian vein, and after passing along the superior vena cava  11  ( FIG. 14 , see the arrow), it is inserted in the right atrium  12  of the heart and passed to the inferior vena cava  13 , where it moves a short section downward ( FIG. 14 ). 
     The transseptal sheath  9  is inserted by femoral route  14  ( FIG. 15 , see the arrow) by means of an appropriate introducer and passed along the inferior vena cava  13  until it reaches the right atrium of the heart  12  after passing through the loop of the Loop Catheter  5 , which has been previously inserted in the inferior vena cava  13  ( FIGS. 15 and 16 ). 
     A puncture on the interatrial septum  15  is performed with a Brockenbrough needle using traditional methods, all the conventional elements being removed when the procedure finishes. Once the puncture  16  is made, the transseptal sheath  9  is passed through the puncture from the right atrium  12  to the left atrium  17  (reference being made to  FIG. 17 ). 
     The elements of this invention are used assembling the Connector  7  of the Cardiac Catheter  6  by inserting it in the pertinent hole of the Fastener  1 , and fixing axially the Pulling Element  2  to the Fastener  1  ( FIG. 10 ). 
     The Mandrel  4  is passed through the Runner  3  ( FIG. 11 ) and the Fastener  1 , and along the central passage of the Cardiac Catheter  6  until it reaches its distal end. With this section, the Mandrel  4  conforms a unit (Kit) between the Runner  3 , the Fastener  1 , the Pulling Element  2  and the Cardiac Catheter  6 , and keeps the Cardiac Catheter  6  unbending to let it go forward and prevent any involuntary movement. The Kit is inserted in the transseptal sheath  9  ( FIG. 12 ). 
     Advancing the Runner  3  forward, the Fastener  1 , the Pulling Element  2 , the Mandrel  4  and the Cardiac Catheter  6  are moved through the transseptal sheath  9  until the distal end of the Cardiac Catheter  6  reaches the left atrium  17  of the heart ( FIG. 18 ). The transseptal sheath  9  is removed from the heart to the inferior vena cava  13  and left at a short distance from the heart. During this partial removal of the transseptal sheath  9 , the Mandrel  4  has an important role keeping the Cardiac Catheter  6  steady in place in the left atrium  17  ( FIG. 19 ). 
     The Mandrel  4  is removed from the distal end to the proximal end of the catheter; removing the Mandrel  4  releases the Cardiac Catheter  6 , which becomes flexible ( FIG. 20 ). 
     The Runner  3  continues to be advanced along the transseptal sheath  9  and the Fastener  1  is pushed until it reaches the inferior vena cava, as illustrated with reference to  FIG. 20 . 
     The Mandrel  4  is completely removed from the Cardiac Catheter  6 , the Fastener  1  and the Runner  3 . On one hand, this procedure detaches the Runner  3 , which remains inside the transseptal sheath  9 ; as illustrated with reference again to  FIGS. 3-12 . On the other hand, it leaves the proximal end of the Cardiac Catheter  6  together with the Pulling Element  2  and the Fastener  1  in the inferior vena cava of the heart as illustrated with reference to  FIGS. 22 and 23 . 
     The Loop Catheter  5  is adjusted by holding the Pulling Element  2 . Removal of the Pulling Element  2  is done by means of the Loop Catheter  5  through the superior vena cava  11  as illustrated with reference to FIGS.  24 , 25  and  26  until the free end of the Pulling Element  2  is taken out through the catheter introducer of the subclavian vein  10 . Eventually, at operator&#39;s discretion, the Pulling Element  2  can be taken out partially and cut, and then the cut section is taken out at the site of the femoral vein. 
     The free end of the Pulling Element  2  is inserted in the central passage of the Aligning device  8  and then inserted in the catheter introducer  19  of the subclavian vein  10  in order to align the set composed of the Fastener  1  connected to the proximal end of the Cardiac Catheter  6  ( FIG. 27 ) and allow its insertion in the catheter introducer of the subclavian vein  10  for smooth removal. 
     The Pulling Element  2 , the Fastener  1  and the proximal end of the Cardiac Catheter  6  are completely removed through the catheter introducer  19  of the subclavian vein  10 , as illustrated with reference to  FIG. 28 . 
     The Fastener  1  and the Pulling Element  2  are detached from the proximal end of the Cardiac Catheter  6 , and the Connector  7  of the Cardiac Catheter  6  is left uncovered. 
     Thus, the proximal end of the Cardiac Catheter  6  is left outside the human body through the subclavian vein  10 , while the opposite end is inserted in the chamber of the left atrium  17  or the left ventricle  18  of the heart ( FIG. 29 ). 
     The procedure finishes when the distal end of the Cardiac Catheter  6  is placed in the desired position inside the left atrium or ventricle using customary techniques, and the pacemaker or any other piece of equipment is implanted using customary procedures. 
     The constructive and functional advantages of this invention by which it is characterized are plain from the description above, representing a beneficial technological improvement that warrants the inclusion of the invention in the law with the pertinent legal protection as per the appended claims.