Physiological Pacing: A New Road to Future

Abstract

Anatomy and physiology are the basis of human body functioning and as we have progressed in management of various diseases, we have understood that physiological intervention is always better than an anatomical one. For more than 50 years, a standard approach to permanent cardiac pacing has been an anatomical placement of transvenous pacing lead at the right ventricular apex with a proven benefit of restoring the rhythm. However, the resultant ventricular dyssynchrony on the long-term follow-up in patients requiring more than 40% ventricular pacing led to untoward side effects in the form of heart failure and arrhythmias. To counter such adverse side effects, a need for physiological cardiac pacing wherein the electrical impulse be transmitted directly through the normal conduction system was sought. His bundle pacing (HBP) with an intriguing alternative of left bundle branch pacing (LBBP) is aimed at restoring such physiological activation of ventricles. HBP is safe, efficacious, and feasible; however, localization and placement of a pacing lead at the His bundle is challenging with existing transvenous systems due to its small anatomic size, surrounding fibrous tissue, long-learning curve, and the concern remains about lead dislodgement and progressive electrical block distal to the HBP lead. In this article, we aim to take the reader through the challenging journey of HBP with focus upon the hardware and technique, selective versus nonselective HBP, indications and potential disadvantages, and finally the future prospects.