The feasibility and efficacy of His-Purkinje system pacing in chronic heart failure with permanent atrial fibrillation

Abstract

Objective To study the feasibility and efficacy of His-Purkinje system pacing (HPSP) in cardiac resynchronization therapy (CRT) candidates of chronic heart failure with permanent atrial fibrillation (AF) . Methods Eighteen patients with chronic heart failure and permanent AFof Zhongshan Hospital, Fudan University from July 2017 to January 2019 were enrolled in the study, including 16 cases with slow ventricular heart rate indicated for ventricular pacing and 2 cases combined with fast ventricular heart rate, QRS duration >130 msreceiving atrioventricular (AV) node ablation. At baseline, 8 cases had narrow QRS duration (<120 ms) , 2 cases had left bundle branch block (LBBB) , and 8 had intraventricular block. All the patients were CRT candidates and received a CRT-P or CRT-D implantation. HPSP lead connected to the RA port of the generator was implanted together with conventional bi-ventricular pacing (BVP) and was programed as HPSP only or fusion with BVP post-procedure. QRS durations were measured and compared during intrinsic, BVP and post-procedure. Pacing parameters were measured and compared during post-implantation immediately and 6 months post-implantation. Echocardiogram parameters, New York Heart Association (NYHA) class and 6 minutes walking distance (6 MWD) were collected and compared between baseline and 6 months post-implantation. Results All the cases were divided into 2 groups: HPSP (n=13, His bundle pacing, n=6) and HPSP fusion with BVP (n=5, His bundle pacing, n=3) . QRS durations were significant different in both two groups as compared to BVP[ (116.7±14.2) ms vs. (156.7±11.1) ms, P<0.000 1]; [ (141.4±9.5) ms vs. (174.6±9.6) ms, P=0.01, respectively]. Pacing parameters including threshold and R wave amplitude were not significant different during post-implantation immediately and 6 months post-implantation in both two groups. Impedance was significant different in HPSP group[ (594.1±104.7) Ωvs. (501.5±74.8) Ω, P=0.016], but was not found in HPSP fusion with BVP group. Left ventricular ejection fraction (LVEF) , left atrium dimension (LAD) , left ventricular end diastolic dimension (LVEDD) , left ventricular end systolic di mension (LVESD) , tricuspid annular plane systolic excursion (TAPSE) , pulmonary artery systolic pressure (PASP) , and the percentages of moderate to severe mitral regurgitation and tricuspid regurgitation were not significantly different between baseline and 6 months post-implantation in both two groups. NYHA class and 6 MWD were significantly different in HPSP group (P<0.000 1) . Conclusion HPSP was feasible and effective in CRT candidates of chronic heart failure with permanent atrial fibrillation. It could significantly reduce QRS duration both in HPSP and HPSP fusion with BVP groups. Moreover, though LVEF was not significantly improved, the pacing parameters were stable and NYHA class and 6MWD were significantly improved in HPSP group after 6 months’follow-up. Key words: Heart Failure; Cardiac pacing, artificial; His-Purkinje conduction system; Atrial fibrillation; Cardiac resynchronization therapy