Leadless ultrasound-based cardiac resynchronization system in heart failure results from the SOLVE-CRT randomised sub-study and the primary population patient cohort

Abstract

Abstract Background Despite the well-established role of CRT in heart failure, major limitations of CRT include an occasional incidence of unsuccessful coronary sinus (CS) lead placement, one third non-responders in conventional CRT patients and higher complications risk in CRT upgrade procedures. The WiSE® CRT System (EBR Systems, Inc) is designed to overcome these limitations. Prior non-randomized studies with the WiSE System have shown high implant success rates and improvement in LV remodeling and heart failure symptoms. Objectives The pivotal SOLVE-CRT study is comprised of two parts: a randomized part and the subsequent single-arm part enrolled during the pandemic. The primary safety endpoint is freedom from Type I (device & procedure-related) complications through 6 months and primary efficacy endpoint is the mean relative (%) change in left ventricular end systolic volume (LVESV) from baseline to 6 months. Method Between Jan. 2018 and Mar. 2020 the randomized part enrolled 108 participants for three indications: non-responders (NR), previously untreated, including acute and chronic lead failures (PU), and high-risk upgrades (HRU). All underwent device implantation and were then randomized in 1:1 ratio to Treatment (system turned ON) or Control (system turned OFF) groups. In the single arm, 75 participants had been enrolled within two indications: PU and HRU. The efficacy analysis of the entire randomised cohort included 99 participants (PU, HRU, NR). For the primary indication sub-population, 57 participants (PU, HRU) were analysed. Results Randomized Group: Results were available for 91 of the 99 patients. Significant improvements were seen between the Treatment and Control groups with a mean reduction in LVESV (-14.6% vs -5.2%, p=0.005), mean reduction in LVEDV (-8.1% vs -3.0%, p=0.027), mean increase in LVEF (5.4% vs 2.4%, p=0.048) and mean reduction in QRS (-41.9ms vs -1.7ms, p=0.001). Primary Indication Sub-Population Group: The primary indication sub-population also saw significant improvements between Treatment and Control group with a mean reduction in LVESV (-18.2% vs -3.1%, p=0.002), mean reduction in LVEDV (-11.6% vs -2.1%, p=0.004), mean increase in LVEF (5.7% vs 1.1%, p=0.025) and mean reduction in QRS (-38.0ms vs -3.1ms, p<0.001). Conclusion This pivotal SOLVE-CRT trial demonstrates that leadless, ultrasound-based endocardial pacing for heart failure is feasible and efficacious showing evidence of left ventricular remodelling and electrical response after 6 month in the primary population as well as in the sub-study group. Picture 1: Efficacy entire randomised population Picture 2: Efficacy primary indications population