Implantable medical device

An implantable medical device configured for entire placement within a heart, said device comprising:

• a single flexible body having a first terminal end spaced apart from and opposite a second terminal end;
• at least four conductive electrodes linearly spaced apart from each other along the length of the single flexible body and configured to be positioned in electrical communication with a target tissue of a patient;
• and
• electronic components comprising a battery, a capacitor and an integrated circuit, contained within the single flexible body, at least one of the components being selectively electrically coupled to the at least four conductive electrodes to receive electrical signals therefrom;
• wherein the single flexible body has a length that allows for entire residence within the heart, including residence of the first terminal end in a patient's blood vessel over the left side of the heart, and residence of the second terminal end within the right ventricle, and the at least four electrodes are spaced apart so as to place a first electrode over the left ventricle, a second electrode over the left atrium, a third electrode within the right atrium and a fourth electrode within the right ventricle.