Reducing Ventricular Pacing Frequency in Patients With Atrioventricular Block
Is It Time to Change the Current Pacing Paradigm?
This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
With aging of the general population, an increased incidence of conduction disease will result in an increased need for permanent pacemaker therapy. According to the 2015 European Heart Rhythm Association (EHRA) White Book, in the 56 member countries of the European Society of Cardiology (ESC), the pacemaker implantation rate has increased from a mean implantation rate of 614 per million inhabitants in 2010 to 641 in 2014, thus growing at a rate of about 0.4% to 0.6% per year.1
Much has been learned from clinical studies to identify optimal device mode selection and device programming for an individual patient to maximize the benefits of cardiac implantable electronic device therapy, as well as to minimize any potential adverse outcomes caused by ventricular pacing (VP). Several clinical studies have reported that chronic right ventricular (RV) pacing has detrimental effects on cardiovascular outcomes, including adverse cardiac remodeling, atrial fibrillation (AF), congestive heart failure (HF), and mortality. The potential mechanism(s) by which RV pacing increases the risk for HF and AF are not completely elucidated, but are likely caused by both electric and mechanical dyssynchrony, disruption of sympathetic/parasympathetic balance that alters myocardial activation pattern and contraction sequence, thereby modifying myocardial strain resulting in less efficient contraction. These changes lead to chamber enlargement, functional mitral regurgitation, reduction of parasympathetic/sympathetic balance in response to reduced ventricular output, and contribute to the development of HF and AF. Notably, not all patients paced in the RV experience adverse outcomes; these detrimental effects seem to be dependent on a high cumulative percentage of RV pacing, generally indicated by >40%. Furthermore, the increased risk of HF has been more frequently observed in those with pre-existing left ventricular (LV) systolic dysfunction. A recent review by Gillis2 has covered the optimal pacing mode for RV and biventricular devices. It is …