CRT Implant Strategy Using the Longest Electrical Delay for Non-left Bundle Branch Block Patients

Inclusion Criteria: * Have non-LBBB morphology (includes complete right bundle branch block and intraventricular conduction delay with a QRS duration ≥ 120ms) * Have the following indication per the 2013 updated American College of Cardiology Foundation/American Heart Association/Heart Rhythm Society guidelines: * Left ventricular ejection fraction (LVEF) ≤ 35%, sinus rhythm, ischemic or non-ischemic cardiomyopathy, a non-LBBB pattern with QRS duration ≥ 120 ms, and NYHA) class III/ambulatory class IV on guideline directed medical therapy * Receiving a new CRT implant or undergoing an upgrade from an existing implantable cardioverter defibrillator or pacemaker implant with no more than 10% right ventricular pacing * Are 18 years or older, or of legal age to give informed consent specific to state and local law * Ability to provide informed consent for study participation and is willing and able to comply with the prescribed follow-up tests and schedule of evaluations Exclusion Criteria: * Irreversible occlusion of venous access that will prevent placement of the CRT system either through the right or left upper extremity venous system * Undergoing left ventricular lead placement via a surgical or epicardial approach * Cardiomyopathy due solely to valvular disease that is not repaired/replaced * Enrolled or intend to participate in a clinical drug and/or device study, which could confound the results of this trial as determined by St. Jude Medical, during the course of this clinical study * LBBB: QRS width ≥ 120 ms, with predominantly negative QRS in lead V1, and upright, monophasic QRS in leads I and V6 * Incomplete right bundle branch block - intraventricular conduction delay with a QRS duration between 110 and 119ms * Persistent or permanent atrial fibrillation * Pacemaker dependent * Patients who are being upgraded primarily due to right ventricular pacing * Women who are pregnant or who plan to become pregnant during the clinical trial * Life expectancy \< 1 year