Cardiac resynchronization therapy (CRT) nowadays is an important part of invasive heart failure therapy (1). Furthermore, it gains increasing recognition for anti-bradycardia pacemaker indications with an expected high burden of ventricular pacing by reducing cardiac remodeling (2). With a considerable number of CRT implantations worldwide, the impact of the recent clinical evaluation of wireless endocardial left ventricular (LV) pacing with a novel wireless cardiac resynchronization system (WiSE-CRT, EBR Systems, Sunnyvale, California, USA) by Reddy et al. 2017 should be further debated (3).
Repeatedly reported issues with CRT have been a high non-responder rate at about 30–40% (4) and suboptimal positioning of the LV electrodes in the coronary sinus in about 10% of patients (5). Canine models suggest the superiority of endocardial LV pacing over transvenous epicardial pacing for acute hemodynamic response (6). Atrial and ventricular transseptal approaches for LV endocardial electrode implantation carry the risk of thromboembolism and the need for oral anticoagulation (7,8). In addition, device related infections with potential endocarditis in an already high-risk population of patients with indications for CRT present a considerable burden (9).
Stimulation Of the Left Ventricular Endocardium for Cardiac Resynchronization Therapy in Non-Responders and Previously Untreatable Patients
Study Phase II
During the early phases (phases 1 and 2), researchers assess safety, side effects, optimal dosages and risks/benefits. In the later phase (phase 3), researchers study whether the treatment works better than the current standard therapy. They also compare the safety of the new treatment with that of current treatments. Phase 3 trials include large numbers of people to make sure that the result is valid. There are also less common very early (phase 0) and later (phase 4) phases. Phase 0 trials are small trials that help researchers decide if a new agent should be tested in a phase 1 trial. Phase 4 trials look at long-term safety and effectiveness, after a new treatment has been approved and is on the market.
ABOUT THIS STUDY
This study is a prospective, multi-center, randomized, controlled, double blinded, pivotal trial to study the safety and efficacy of the WiSE-LV System for Cardiac Re-synchronization Therapy.
Mayo Clinic principal investigator
Yong-Mei Cha, M.D.
Yongmei Cha M.D.