Patent attributes
A cardiac rhythm management system, such as an implantable cardioverter-defibrillator (ICD), provides atrial anti-tachyarrhythmia therapy, such as a bipolar or unipolar electrical cardioversion countershock, or provides both atrial and ventricular anti-tachyarrhythmia therapy. The atrial and ventricular anti-tachyarrhythmia therapies have independent cardioversion-defibrillation energy levels and other parameters. The system provides an endocardial lead that is convenient to implant for providing the anti-tachyarrhythmia therapy. The endocardial lead includes a first supraventricular electrode disposed in the atrium and superior vena cava, and optionally includes a first ventricular electrode and ICD housing electrode.