Abstract: Devices and methods of use for treating atrial arrhythmias. A single-pass lead includes a body portion having at least two electrodes configured to be positioned within or adjacent a right atrium of a heart of a patient, and a distal portion having at least two electrodes configured to be positioned within a blood vessel proximate the left atrium. The lead is configured to operated by an implantable therapy generator programmed to deliver a multi-stage therapy by activating various combinations of at least one electrode of the body portion of the lead and at least one electrode of the distal portion of the lead.