Patent ID: 8417332

Claim:
A system for endocardial stimulation/defibrillation of the left ventricle, comprising: An implantation device housing ( 60 ), comprising at least two terminals and a generator means for delivering between the two terminals electrical pulses of stimulation/defibrillation, and An endocardial lead comprising at least one distal stimulation/defibrillation electrode proximally coupled to one of the two terminals, wherein the lead comprises: A lead body ( 26 ) of a deformable material having a distal end and a distal inner open lumen, the distal end ( 30 ) for extension into the right ventricle cavity ( 14 ), means for anchoring the lead body ( 32 ) to an interventricular septum wall ( 20 ) of a patient and at least one stimulation/defibrillation electrode ( 38 , 64 , 66 ) proximally coupled to one of the two terminals, and At least one structure adapted to be deployed in the left ventricular cavity, comprising a proximal end, an electrically conductive core ( 70 , 72 ), an insulating sheath ( 74 ) about the core, said structure being slidably housed in the distal inner open lumen of the lead body and extending the entire length of the lead body and including beyond the distal end of the lead body, the length of the structure extendable beyond the distal end of lead body comprising: an intermediate portion ( 56 ), for crossing from one side of the interventricular septum wall ( 20 ) to the other side, and an active free portion ( 58 ), for emerging into the left ventricle cavity ( 16 ), said free portion comprising at least one bare region ( 76 , 80 , 82 ) wherein said structure is electrically coupled at its proximal end ( 54 ) to the other of the two terminals of the generator means for producing, upon activation of the generator means, an electric field ( 62 ) between said at least one stimulation/defibrillation electrode ( 38 , 64 , 66 ) of the lead body and said at least one bare region ( 76 , 80 , 82 ) of the active free portion ( 58 ) of said structure, wherein said structure extendable into the left ventricle cavity comprises a microcable ( 42 ) having an electrically conductive core diameter in the active free portion of between 0.2 and 0.4 mm, and comprises a strand formed of a plurality of strands with at least one composite strand ( 68 ) comprising: A first material having properties of mechanical resistance to bending fatigue superior than those of other materials of the strand, and A second material that is radio-opaque.