Substernal electrical stimulation system

A cardiac pacing system comprising:

• a pulse generator configured to provide cardiac pacing therapy;
• an implantable medical electrical lead that includes:
• a lead body having a proximal end and a distal portion;
• a connector configured to couple to the pulse generator at the proximal end of the lead body;
• and
• a plurality of electrodes on the distal portion of the lead body,
• wherein the distal portion of the lead body of the lead is configured to be positioned within the substernal space of the patient and the pulse generator is configured to deliver pacing pulses to an atrium of a heart of the patient using at least a first pair of electrodes of the plurality of electrodes and deliver pacing pulses to a ventricle of the heart of the patient via at least a second pair of electrodes of the plurality of electrodes, the first pair of electrodes and the second pair of electrodes being electrically coupled to a therapy circuitry of the pulse generator, the first pair of electrodes and the second pair of electrodes being positioned on the distal portion of the lead body that is configured to be positioned within the substernal space, the first pair of electrodes being spaced apart from the second pair of electrodes such that the first pair of electrodes are configured to deliver pacing pulses to the atrium of the heart of the patient and the second pair of electrodes are configured to deliver pacing pulses to the ventricle of the heart of the patient, wherein a distance between the first pair electrodes and the second pair of electrodes is greater than a distance between each electrode of the first pair of electrodes.