The Heart Rhythm Society (HRS) has announced the findings of three clinical trials demonstrating positive outcomes of conduction system pacing (CSP) for patients in need of cardiac resynchronisation therapy (CRT). The studies were presented as late-breaking clinical science at HRS 2022 (29 April–1 May, San Francisco, USA).
CRT is a treatment that uses pacing to target abnormal heartbeats and restore heart function for patients with heart failure and conduction abnormalities. As a key strategy to address heart rhythm disorders, researchers are continuously evaluating the latest approaches to deliver cardiac pacing safely and effectively. The traditional, standard approach to CRT has been biventricular pacing. Over the last decade, evidence around His bundle pacing and left bundle branch pacing (LBBP) has grown to offer alternative solutions.
Findings of the LBBP-RESYNC trial indicate LBBP-CRT could potentially be considered a first-line resynchronisation strategy alongside BiVP-CRT in patients with heart failure. This study is the first prospective randomised head-to-head controlled trial to compare the clinical efficacy between LBBP and BiVP, HRS said in a press release.
In the study, the LBBP-CRT group significantly increased left ventricular ejection fraction compared to BiVP-CRT, using intention-to-treat analysis (p=0.029).
“We are encouraged by our results and the potential for left bundle branch pacing as a first-line strategy for CRT in heart failure patients with non-ischemic cardiomyopathy and left bundle branch block,” said Jiangang Zou (First Affiliated Hospital, Nanjing Medical University, Nanjing, China) and principal investigator of the LBBP-RESYNC trial. “As the number of patients with heart failure continues to grow, it’s important to have alternative options for resynchronisation therapy especially in patients less likely to respond to conventional biventricular pacing.”
‘Clinical outcomes of conduction system pacing compared to biventricular pacing in patients requiring cardiac resynchronization therapy’, a non-randomised, observational, retrospective, two-centre study showed CSP improved clinical outcomes when compared to BiVP in a large cohort of patients with class I or II indications for CRT.
CSP was associated with significant reduction in the combined endpoint of time to death or heart failure hospitalisation (28.3% vs 38.4%; HR 1.52; CI 1.082-2.087; p=0.013).
“The results of this study help establish conduction system pacing as an additional and even alternative treatment option to the traditional biventricular approach. It is exciting and vital to our patients to have options when it comes to pacing solutions,” said Pugazhendhi Vijayaraman, (Geisinger Heart Institute, Danville, USA), the study’s principal investigator.
In a further presentation, results from the international LBBAP collaborative study group demonstrate that left bundle branch area pacing (LBBAP) is a viable alternative option for CRT in patients who failed traditional BiVP due to coronary sinus lead implantation failure or failure to respond to biventricular pacing. In the retrospective, multicentre study, rescue LBBAP was found to be feasible in 200 of 212 (94%) patients.
“These findings are promising, especially for patients where the traditional strategy has
failed,” said Vijayaraman. “We look forward to future larger, randomised trials to further validate conduction system pacing as a safe and effective tool to deliver cardiac resynchronisation therapy.”
