Abstract
An electrode arrangement, for the temporary stimulation or defibrillation of the heart includes at least one unipolar electrode configured to be secured on the myocardium of the heart. An indifferent electrode is configured to be secured on the inner wall of the thorax via its supply line and be positioned such that direct contact with the heart is prevented. An external pacemaker is in electronic communication with the at least one unipolar electrode and the indifferent electrode such that negative poles of the indifferent electrode are combined into a single cable.
Claims
1. An electrode arrangement, for the temporary stimulation or defibrillation of the heart, comprising: at least one unipolar electrode configured to be secured on the myocardium of the heart; an indifferent electrode configured to be secured on the inner wall of the thorax via its supply line and be positioned such that direct contact with the heart is prevented; and an external pacemaker in electronic communication with the at least one unipolar electrode and the indifferent electrode, wherein negative poles of the indifferent electrode are combined into a single cable.
2. An electrode arrangement according to claim 1, wherein the indifferent electrode is metallic and made of platinum, Nitinol, MP 35N, biocompatible stainless steel or conductive synthetic material.
3. An electrode arrangement according to claim 1, wherein the indifferent electrode is provided as a metal coil, metal braiding, metal strand, metal wire, metal ribbon or metal weave.
4. An electrode arrangement according to any one of claim 1, wherein the indifferent electrode consists of at least one metallic coil.
5. An electrode arrangement according to claim 4, wherein the metallic coil is embedded in a tube made of synthetic material, preferably silicone, said tube having openings, wherein the openings are located on the side facing the heart.
6. An electrode arrangement according to claim 1, wherein the indifferent electrode is made of metal braiding.
7. An electrode arrangement according to claim 6, wherein the metal braiding comprises a membrane having openings on the side facing the heart, said membrane preferably being made of silicone.
8. An electrode arrangement according to claim 1, wherein the indifferent electrode is designed straight, spiral-shaped, disc-shaped, shamrock-shaped, latticed, ribbon-shaped or polygonal or has the shape of a tennis racquet.
9. An electrode arrangement according to claim 1, wherein the indifferent electrode is secured in the patient's thoracic wall by means of a synthetic part.
10. An electrode arrangement according to claim 1, wherein the indifferent electrode comprises a membrane made of soft synthetic material, preferably silicone on the side facing away from the heart.
11. An electrode arrangement according to claim 1, wherein two positive poles from the unipolar electrode are positioned through the abdominal wall and in communication with the external pacemaker, and wherein one cable from the indifferent electrode is positioned through the abdominal wall and in communication with the external pacemaker.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Additional specifics, characteristics and advantages of the invention can be gathered from the descriptive part below, in which the invention is explained in more detail based on the drawings and exemplary embodiments.
[0027] FIG. 1 shows the field strength distribution of an exemplary arrangement for stimulation of the heart with an indifferent electrode outside the heart;
[0028] FIG. 2a shows the prior art temporary dual chamber electrical heart stimulation with an external pacemaker after heart surgery;
[0029] FIG. 2b shows electrical heart stimulation with an external pacemaker according to the present disclosure;
[0030] FIG. 3 shows an exemplary view of the feed-through of an indifferent electrode through the thoracic wall;
[0031] FIG. 4 shows an exemplary large surface area disc-shaped indifferent electrode;
[0032] FIG. 5 shows a further exemplary indifferent electrode having a large surface area made from metal braiding;
[0033] FIG. 6 shows yet another exemplary indifferent electrode having a large surface area;
[0034] FIG. 7a shows one more exemplary indifferent electrode having a large surface area in the shape of a tennis racquet illustrating the indifferent electrode made of metal coils; and
[0035] FIG. 7b shows the indifferent electrode of FIG. 7a illustrating the coils coated with a silicone tube.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] Reference will now be made to the drawings wherein like reference numerals identify similar structural features or aspects of the subject disclosure. For purposes of explanation and illustration, and not limitation, a partial view of an exemplary embodiment of an implantable indifferent electrode in accordance with the disclosure is shown in FIG. 1 and is designated generally by reference characters 2a and 2b.
[0037] FIG. 1 shows the field strength distribution 1 of an arrangement according to the present disclosure, wherein the indifferent electrode 2a, 2b is positioned outside the heart. The indifferent electrode 2a, 2b is created as metallic polished coil 3 in part 2a. However, the coil can also be embedded in a protective tube made of synthetic material, preferably silicone 4, said tube having openings 5 toward the outside such that an electrical current can flow through the openings between the unipolar electrode (cathode) 6 and the indifferent electrode 2a, 2b. The indifferent electrode 2a, 2b is positioned such that there is no direct contact of the electrodes during heart stimulation.
[0038] Referring to FIG. 2a a prior art temporary dual chamber electrical heart stimulation with an external pacemaker 50 after heart surgery is shown. The external pacemaker 50 stimulates alternately both chambers of the heart, the right atrium and the right ventricle, with two poles and therefore two unipolar wires for each chamber. Each pole 51, 52 of the wire has to be fixed within the wall of the heart (myocardium) in such a way as to allow the stimulation of the heart but also to allow the heart wires 51a, 52b to be removed through a percutaneous incision within the thorax region when their use is terminated.
[0039] In contrast, with reference to FIG. 2b, connection between the indifferent electrode 2a of the present invention and an external pacemaker 40 is shown. The external pacemaker 40 stimulates the right atrium and the right ventricle alternately at the end of an open heart surgical procedure to provide post-surgical temporary pacing and monitoring. The field strength distribution 1 between the right ventricle and the indifferent electrode 2a below the heart is shown during the stimulation of the right ventricle. A similar field strength appears when the right atrium is electrically stimulated. The end of the coil is an isolated lead cable 42 attached outside the abdominal wall 43 to a connector pin 41.
[0040] The present disclosure reduces the number of cables through the abdominal wall. In FIG. 2a (prior art) the unipolar electrode pole 51 fixed at the atrium and unipoloar electrode 52 fixed at the ventricle each need a counter electrode, thus four cables are hanging out from the abdomen 53. FIG. 2b shows that with the present disclosure the negative poles 41a of the indifferent electrode 2a are combined into one metal coil having one cable 42 through the abdomen wall 43. The metal coil is not fixed within the wall of the heart it is arranged near the apex of the heart.
[0041] FIG. 3 shows an exemplary fixation of the indifferent electrode through the thoracic wall 7. The lead-through of the indifferent electrode through the thoracic wall 7 can be achieved with a moulded part made of silicone, wherein the moulded silicone part is fixated on the side of the electrode supply line by means of a ligature 20. A chest needle 9 is used to pull the indifferent electrode from the inside to the outside through the thoracic wall. Based on its undulating shape 10, the silicone part 8 can match the respective anatomical conditions of the chest wall thickness. The silicone part 8 can also be combined with the indifferent electrode 4 to form a joint moulded part.
[0042] FIG. 4 shows an exemplary disc-shaped indifferent electrode having a large surface area 11. It serves as temporary indifferent electrode for the stimulation of the heart, but can likewise be used as permanent indifferent electrode for implanted pacemakers or implantable cardioverter-defibrillators (ICDs). To prevent direct contact between the coil (12) and the outer wall of the heart, the coil 12 can again, as described in FIG. 1, be integrated into a silicone tube having openings or into a silicone membrane having openings 14. The openings are necessary for the current to flow. A cable 15 connected with a detachable coupling 16, which is pushed through to the outside with a chest needle 30 is used to create the temporary connection with the external pacemaker.
[0043] FIG. 5 shows an additional exemplary indifferent electrode having a large surface area 17 made from metal braiding. It is a highly-flexible umbrella braided with individual Nitinol 13 wires. The umbrella is insulated toward the side of the chest with a silicone layer 18 and coated with a perforated silicone membrane 19 toward the side of the heart. A cable 15 connected with a detachable coupling 16 is again used to create the temporary connection with the external pacemaker.
[0044] FIG. 6 shows a further exemplary indifferent electrode having a large surface area 20. The perforated silicone sections 21 are designed straight and can be connected as one or a plurality of indifferent electrodes as desired. Optionally, the silicone membrane 22 can be reinforced with fabric made of synthetic material (e.g. Dacron). The electrode is secured on the inside of the chest wall with ligatures, medical adhesive or other common surgical fixation devices. Metallic coils made of platinum, MP35N or other biocompatible conductive materials are used as poles. The supply line for the coil consists of a highly flexible internal metallic strand welded to the coil at the end. Metal braiding, metal weave, metal strand, metal ribbons or metal hemispheres or poles made of conductive synthetic material can be used aside from poles consisting of a coil. As well, the outer shape of the indifferent electrode can have a multiform design depending on the anatomical conditions (circular, rectangular, shamrock-like, latticed, in the shape of ribbons, squares, polygons, etc.). Aside from silicone, suitable membrane materials include polyurethane, PTFE, polyamide, Pebax and other biocompatible materials, which are suitable as long-term implants.
[0045] FIG. 7a and FIG. 7b show another exemplary indifferent electrode having a large surface area made of metal coils 24, arranged in the shape of a tennis racquet 23. The coils are insulated toward the side of the chest by a silicone membrane 26 and coated with a perforated silicone tube 25 toward the side of the heart. A cable 27 connected with a detachable coupling (not illustrated here) is again used to create the connection with the external pacemaker.
[0046] The system of the present disclosure, as described above and shown in the drawings, provide for an implantable indifferent electrode with superior properties including heart stimulation without the need for direct contact to the heart. While the apparatus and methods of the subject disclosure have been shown and described with reference to preferred embodiments, those skilled in the art will readily appreciate that changes and/or modifications may be made thereto without departing from the scope of the subject disclosure.
