Efficacy of Leadless Ultrasound-Based Left Ventricular Endocardial Pacing for Cardiac Resynchronization Therapy: A Meta-Analysis

Heart failure with reduced ejection fraction is a major cause of morbidity and mortality. Cardiac resynchronization therapy (CRT) improves outcomes but faces challenges such as unsuccessful lead placement and suboptimal responses. The Wireless Stimulation Endocardially for CRT (WiSE-CRT) system, a novel leadless left ventricular (LV) pacing technology, uses ultrasonic energy to deliver electrical stimulation directly to the LV endocardium, potentially improving the response rates. A comprehensive literature search was performed across multiple databases from inception until August 2024. The outcomes of interest included the New York Heart Association (NYHA) functional score, LV ejection fraction (LVEF), LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), and QRS duration. Statistical analysis involved pooling the mean differences (MDs) and their corresponding 95% confidence intervals (CIs) from each study using the inverse-variance random-effects model in RevMan version 5.4.1 software. Seven studies, including 468 patients with heart failure treated with the WiSE-CRT system, were included. The pooled analysis showed significant improvements in NYHA functional score (MD: -0.44; 95% CI: -0.67 to -0.21; P = 0.0002; I2 = 77%), LVEF (MD: 5.71; 95% CI: 4.54 to 6.87; P < 0.001), LVEDV (MD: -24.49; 95% CI: -33.24 to -15.73; P < 0.001), and LVESV (MD: -24.47; 95% CI: -32.80 to -16.14; P < 0.001). The QRS duration also decreased significantly (MD: -38.62; 95% CI: -46.76 to -30.49; P < 0.001; I2 = 60%). The WiSE-CRT system significantly improved NYHA functional score, LVEF, QRS duration, LVEDV, and LVESV in patients with heart failure. This leadless pacing technology offers a promising alternative for ineligible candidates or for those who do not respond to conventional CRT.