Occurrence of adverse outcomes in patients with pacing-induced cardiomyopathy: a retrospective study

Pacemaker implantation is recommended as a treatment for several diseases, mainly atrioventricular block (AVB) and sinus node disease. Despite all the proven benefits, these devices can result in electromechanical desynchrony and, consequently, in pacing-induced cardiomyopathy (PICM), causing ventricular remodeling and higher rates of hospitalizations and mortality.

To study the prevalence of PICM and the occurrence of Major Adverse Cardiac Events (MACE) in patients with high percentage of right ventricular pacing (%RVP, >90%) compared with low %RVP (<10%).

Observational, analytical and retrospective study, which included patients who underwent pacemaker implantation between January 2015 and December 2017. A 5-year follow-up period was performed and MACE defined as mortality, hospitalization due to heart failure and upgrade to CRT at 1 and 5 years.

The group of patients with RVP> 90% (n= 394) was characterized by a higher median age (86 years (IQR 10), p< 0.001) and a higher proportion of men (62.9%, p= 0.001). It presented a lower minimum heart rate (35 bpm (IQR 10), p< 0,001) and higher NT-proBNP (1789 ng/mL (IQR 5227), p< 0.001) prior to implantation. The atrioventricular block was the most prevalent indication for pacemaker implantation in RVP>90% (77.9% vs. 49.4%), whereas sinus node disease was more prevalent in RVP<10% (45,4% vs. 4,3%). The incidence of PICM in the pacemaker population was 14.6% and the average time until its development was 32.3 ± 18 months. After 5 years, the RVP>90% group had a higher mortality (36.8% vs. 27,3%) and hospitalization rate due to heart failure (9.1% vs. 3,2%), compared to the RVP<10% group (n= 249).

Patients with %RVP >90% have a higher incidence of mortality and re-hospitalization due to heart failure in five years follow-up. The roles of prevention and timely detection of PICM must be reinforced.