One embodiment of the present invention provides an implantable cardioverter-defibrillator for subcutaneous positioning over a patient's ribcage, the implantable cardioverter-defibrillator including a housing, wherein the housing conforms to the patient's ribcage when subcutaneously positioned; an electrode disposed upon a portion of the housing; and an electrical circuit located within the housing, wherein the electrical circuit is electrically coupled to the electrode.