Title : Does conduction system pacing preserve left ventricular ejection fraction and prevent the development of dyssynchronous cardiomyopathy?
Abstract:
Background: It is well known that conventional right ventricular (RV) pacing results in left ventricular dyssynchrony. Approximately 30% of patients with normal baseline ejection fraction (EF) and >40% of RV pacing will go on to develop cardiomyopathy and heart failure. Conduction system pacing (CSP) is now increasingly used as a mode of resynchronization to correct dyssynchronous heart failure. However, guidelines do not recommend resynchronization pacing for patients with preserved EF, and there are few data to show that preemptive CSP in such patients prevents development of cardiomyopathy.
Methods: We reviewed electronic medical records of all patients with normal baseline EF with anticipated high percentage of ventricular pacing who received CSP devices, had >90% ventricular pacing, and had a minimum of 3 weeks of follow up. Baseline clinical characteristics and EF were collected and compared to latest follow-up data.
Results: A total of 50 patients were included (24 His bundle and 26 left bundle branch area pacing). Baseline characteristics are shown in table 1. At a mean follow-up of 516+523 (range 15-2,066) days there was no significant change in EF (61±5% vs 60±8%, p=0.11) or left ventricular end diastolic diameter (4.5±0.7 vs. 4.4±0.6 cm, p=0.24) despite a high percentage (91%) of pacing (Table 2).
Conclusions: CSP preserves EF over medium-term follow-up and prevents development of dyssynchronous heart failure. If validated in larger cohorts with longer follow up, CSP should be considered as the pacing modality of choice in patients with anticipated high percentage of ventricular pacing, even when baseline EF is normal.
Audience Take Away
CSP preserves EF over medium-term follow-up and prevents development of dyssynchronous heart failure. If validated in larger cohorts with longer follow up, CSP should be considered as the pacing modality of choice in patients with anticipated high percentage of ventricular pacing, even when baseline EF is normal.
