His Bundle Pacing: A New Frontier in the Treatment of Heart Failure

Abstract

Biventricular pacing has revolutionised the treatment of heart failure in patients with sinus rhythm and left bundle branch block; however, left ventricular-lead placement is not always technically possible. Furthermore, biventricular pacing does not fully normalise ventricular activation and, therefore, the ventricular resynchronisation is imperfect. Right ventricular pacing for bradycardia may cause or worsen heart failure in some patients by causing dyssynchronous ventricular activation. His bundle pacing activates the ventricles via the native His-Purkinje system, resulting in true physiological pacing, and, therefore, is a promising alternate site for pacing in bradycardia and traditional CRT indications in cases where it can overcome left bundle branch block. Furthermore, it may open up new indications for pacing therapy in heart failure, such as targeting patients with PR prolongation, but a narrow QRS duration. In this article we explore the physiology, technology and potential roles of His bundle pacing in the prevention and treatment of heart failure.

Increased capture threshold in permanent His‐bundle pacing associated with flecainide

“…Interest in direct PHBP has grown rapidly in recent years as an alternative to right ventricular or biventricular pacing for prevention of pacing‐induced cardiomyopathy as well as for cardiac resynchronization in patients with heart failure and left bundle branch block. The development of a dedicated pacing lead and sheaths for PHBP implantation has further enhanced feasibility for routine clinical use 1 . Several observational studies have demonstrated a reduction in adverse cardiovascular events with PHBP compared to right ventricular pacing (RVP) in patients with bradycardia requiring pacemaker implantation 2,3 .…”

Transient rise in His‐lead threshold due to acute myocardial infarction

“…Right ventricular (RV) pacing has a long‐standing and well‐documented reputation for causing dyssynchronous activation of the ventricles, leading to an increased risk of atrial fibrillation and heart failure . Multiple studies have attempted to determine whether sites different to the RV apex (such as the RV septum) show superior clinical outcomes, and reduce the risk of pacing‐induced ventricular dysfunction, but to date none have been able to show this.…”

“…However, due to the lack of dedicated equipment available to permanently implant such leads, interest dropped, and it is only in the 21st century where the first article was published to support its cause . More recently, dedicated delivery sheaths and the discovery that the Select Secure 3830 active RV lead (Medtronic) with an active screw allows His bundle pacing to be delivered more successfully has caused interest to rapidly grow . Studies are underway to assess its potential to compete with biventricular pacing to improve heart failure symptoms while maintaining ventricular synchrony.…”

“…Right ventricular (RV) pacing has a long-standing and well-documented reputation for causing dyssynchronous activation of the ventricles, leading to an increased risk of atrial fibrillation and heart failure. [1][2][3] Multiple studies have attempted to determine whether sites different to the RV apex (such as the RV septum) show superior clinical His pacing has been around for almost five decades, first demonstrated in man in 1970 by Narula et al 4 Pacing through the His-Purkinje system allows normal activation of the ventricles to be achieved, thus preventing the LV desynchrony caused by RV apical pacing. However, due to the lack of dedicated equipment available to permanently implant such leads, interest dropped, and it is only in the 21st century where the first article was published to support its cause.…”

“…5 More recently, dedicated delivery sheaths and the discovery has caused interest to rapidly grow. 3 Studies are underway to assess its potential to compete with biventricular pacing to improve heart failure symptoms while maintaining ventricular synchrony. One of the difficulties of His bundle pacing is that pacing thresholds are usually higher than traditional RV pacing.…”