Background CRT shows benefit in patients with depressed LVEF, Heart Failure symptoms and prolonged intraventricular conduction, however, 30-40% of CRT patients do not respond to therapy and 8-10% do not receive CRT due to anatomical constraints. Endocardial stimulation promises to improve therapy response, but placing traditional leads endocardially presents safety concerns. The SOLVE CRT Study aims to evaluate the safety and efficacy of the WiSE CRT (Wireless Stimulation Endocardially) System for CRT. Therapy The WiSE CRT System uses ultrasound to WIRELESSLY transmit power to an electrode in a CUSTOMIZED LV pacing location ENDOCARDIALLY, accomplishing synchronous RV & LV pacing = BiV pacing for CRT SOLVE CRT Patient Population CRT NON-RESPONDERS or, PREVIOUSLY UNTREATABLE due to failed CS lead implantation, or CS lead programmed off or, HIGH RISK UPGRADES with contraindications to CS lead implant Design Multi-center, randomized, two-arm, double blinded, prospective trial with 350 PATIENTS at up to 45 INVESTIGATONAL SITES in the U.S., Europe, and Australia. Study begins in 2018 and continues until FDA approval estimated in Q4 2020. Control patients cross-over after 6 month primary endpoint evaluation Endpoints - PRIMARY SAFETY - Freedom from Type 1 Complications reported through 6 months compared to a performance goal - PRIMARY EFFICACY - LVESV Mean Change, LVESV Distribution Shift, Clinical Composite (NYHA, Health Status (KCCQ), Death and HF Event) - SECONDARY EFFICACY - Acoustic Pacing Capture Threshold (APCT) measured at 6 months, Acoustic Pacing Capture Threshold Stability (APCT Stability) measured at pre-discharge through 6 months - TERTIARY EFFICACY - NT-proBNP Mean Change, Proportion of subjects with a greater than 5% improvement in EF from baseline to 6 months, Mean change in intrinsic QRS duration from baseline to 6 months, Percent subjects with at least 1 NYHA Class improvement from baseline to 6 months.