Downside of Right Ventricular Apical Pacing

Downside of right ventricular apical pacing

Right ventricular apical pacing, the usual method of pacing the right ventricle in single chamber and dual chamber pacing, can be deleterious in the long run, as the normal activation sequence of the left ventricle is altered. ECG in right ventricular pacing has a left bundle branch block pattern and hence the left ventricular activation sequence can produce intra-ventricular dys-synchrony with lateral wall contracting later than the septum.

This dys-synchrony can in the long run cause left ventricular dysfunction due to wasted systolic effort. Long term right ventricular apical pacing can also have deleterious effects on left atrial structure and function. There can be a higher chance for atrial fibrillation and heart failure. Hence various algorithms to reduce ventricular pacing have been developed.

Right ventricular outflow or septal pacing have also been proposed as alternatives. When there is left ventricular dysfunction along with an indication for ventricular pacing, biventricular pacing or cardiac re-synchronization therapy can be preferred over conventional right ventricular pacing, in view of these considerations. Right ventricular pacing can cause worsening of mitral regurgitation, which can regress on upgradation to cardiac resynchronization therapy.

Newer pacing modalities like His bundle pacing and left bundle branch block correction are aimed at preventing right ventricular pacing induced left ventricular dyssynchrony and dysfunction in the long term [1]. But these newer modalities have a higher learning curve and needs different hardware and long term data is emerging. So only time will say if they are here to stay.

Reference

  1. Amal Muthumala, Weijian Huang, Pugazhendhi Vijayaraman. Decoding Left Bundle Branch Block: Insights Into the Future of His-Purkinje Conduction System Pacing. J Thorac Dis. 2019 May;11(5):1742-1745.