Introduction
It is well known that long-term right ventricular paving (RVP) might lead to a long QRS duration (QRSd) and left ventricular (LV) dyssynchrony and consequently result in LV systolic dysfunction. And more and more studies have demonstrated that conventional pacing sites (i.e., the apex or septum) could increase mortality and hospitalization of heart failure in pacemaker-dependent patients [1-3]. However, the incidence of PICM remains relatively high, and no response to cardiac resynchronization therapy (CRT) for these patients. And the biventricular pacing upgrade is still not the optimal recommendation (IIb) for these patients in recent guidelines [4].
What would help those patients with PICM? His-Purkinje system pacing, including HBP and LBBP, was chosen as an alternative procedure in patients with indications of bradycardia or heart failure [4]. The safety and efficiency have been confirmed by recent publications [5-7]. However, studies focusing on the outcome of HBP and LBBP upgrades in PICM patients are extremely rare [8, 9]. It is unknown whether this is an effective procedure in patients with PICM and AF. We consequently performed this study to investigate the clinical outcome of HBP and LBBP upgrades in these patients.