Evaluation of left ventricular dysfunction after single-chamber pacemaker implantation in patients with normal left ventricular function in a tertiary care institution in South India: An observational study

Background: In pacemaker recipients with preserved left ventricular ejection fraction, there is scant evidence regarding the effect of single-chamber pacing on left ventricular systolic function. The objective of the study was to assess the echocardiographic progression of pacemaker patients with preserved left ventricular ejection fraction at the baseline in relation to the level of right ventricular pacing and indication for pacing. Methodology: The clinical and diagnostic data from 200 patients who had undergone pacemaker implantation during 2018–2019 were analyzed. Of 200 patients, 32 patients were not included in the study in view of their baseline ejection fraction being <55% in 22 patients, loss to follow-up in six patients, and owing to four patients dying during the study. At admission and after a year of follow-up, the patient's biodata, indications for pacemaker insertion, pacing percentage and echocardiographic parameters, and treatment profile were recorded. Results: A total of 168 patients (48.2% of males and 51.8% of females) were implanted with single-chamber permanent pacemaker. By 1 year, the mean ejection fraction, which was 61.47%, had significantly dropped to 50%. Mitral annular tissue velocity diastolic (E/e′) increased significantly (>4%) after 1 year compared to the baseline. By 1 year, there has been a significant (>10%) change from the baseline in the transannular plane systolic excursion parameter. The left ventricular systolic dysfunction happened in a greater degree in patients with advanced conduction disease compared to those who had sinus node dysfunction. Conclusion: Clinically significant left ventricle dysfunction and right ventricle dysfunction developed in a large number of pacemaker recipients with normal left ventricular function at the baseline.