Model 4396 Left Ventricular (LV) Lead Chronic Performance Study

Patients who meet all of the following inclusion criteria and do not meet any of the following exclusion criteria are eligible for enrollment. Inclusion Criteria * Patient or legally authorized representative provides written authorization and/or consent per institution and geographical requirements * Patient has or is intended to receive an Attain Ability Model 4396 LV lead * Patient within 30 day post implant enrollment window Exclusion Criteria * Patient who is, or is expected to be inaccessible for follow-up * Patient with exclusion criteria required by local law * Patient is currently enrolled in or plans to enroll in any concurrent drug and/or device study that may confound results