Cardiac resynchronization therapy with His bundle pacing.

Abstract

A novel therapy offering cardiac resynchronization therapy (CRT) with an additional lead placed in His bundle has been reported in a few case reports and case series as improving the hemodynamical and clinical condition of patients with permanent atrial fibrillation (AF) in whom other therapeutic methods have not been successful. Fourteen consecutive patients with permanent AF, heart failure (HF), bundle branch block (BBB) with QRS complex width>130ms, and impaired left ventricular ejection fraction (LVEF) underwent implantation of implantable cardioverter defibrillator (ICD)/CRT systems with His bundle pacing (HBP). During the follow-up, we assessed the efficacy of ICD/CRT systems with HBP in HF treatment. The study cohort consisted of 14 patients with the mean age of 67.35±10 years. The mean duration of QRS was 159.2±28.6ms, mean LVEF was 24.36±10.7%, and mean follow-up duration was 14.4 months. One patient died due to HF aggravation during the follow-up. In the remaining 13 patients, the mean LVEF significantly improved from 24% to 38%, P=0.0015. The left ventricular end-diastolic dimension decreased from 72mm to 59mm, P<0.001; left ventricular end-systolic dimension decreased from 59mm to 47mm, P=0.0026. The mean QRS duration shortened from 159ms to 128ms, P=0.016. The mean percentage of HBP reached 97%. As a result, 92.3% of patients demonstrated significant improvement in the New York Heart Association functional class, P<0.001. The use of atrial channel for HBP, choice of optimal ICD/CRT pacing configuration, and optimization of pharmacological therapy resulted in a substantial narrowing of QRS width and clinical improvement in left ventricular mechanical function during the follow-up.