Abstract
Introduction: Right ventricular (RV) pacing can negatively affect left ventricular (LV) function. Therefore, we aimed to assess the role of ventricular strain measured by speckle tracking echocardiography [STE] in the early prediction of LV dysfunction after pacemaker implantation.
Methods: Seventy-five patients with high-degree atrioventricular (AV) block scheduled for permanent pacemaker implantation with good LV systolic function were evaluated. STE was used to assess the left ventricular global longitudinal strain [GLS] 1 month after pacemaker implantation. Patients were followed after 1 year to detect patients with pacemaker-induced cardiomyopathy [PICM] and pacemaker-induced ventricular dysfunction [PIVD].
Results: patients with PICM and PIVD had significantly lower 1-month GLS with no significant statistical difference regarding LV ejection fraction. The percentage of pacing was substantially higher among PICM patients (P 0.0001). Multivariate regression analysis revealed that age, one-month GLS, QRS duration after pacing, and percentage of pacing are independent predictors of one-year LV dysfunction. The ROC curve showed that one-month GLS≥-16 (sensitivity=95.65%, specificity=98.08%, AUC=0.979, P=0.001), QRS duration after pacing≥145 msec (sensitivity=47.83%, specificity=90.38%, AUC=0.824, P=0.001), and percentage of pacing≥84% (sensitivity=65.22%, specificity=90.38%, AUC=0.910, P=0.001) were the best diagnostic values for predicting LV dysfunction.
Conclusion: STE changes are earlier than LVEF in predicting LV dysfunction after RV pacing. It should be used to assess patients undergoing pacemaker implantation to predict those more likely to develop LV dysfunction.