Global Longitudinal Strain to Predict Pacing Induced Ventricular Dysfunction

Background: Chronic RV pacing leads to asynchronous left ventricular activation which in turn predisposes to deleterious effects on the left ventricular (LV) function leading to reduction in the left ventricular ejection fraction (LVEF) and pacing induced ventricular dysfunction (PIVD).Aim: The aim was to study the effects of right ventricular pacing on left ventricular function by deformation imaging using 2D speckle tracking echocardiography.Methods: The study included 50 patients with normal LVEF (≥55%) who underwent single and dual chamber pacemaker implantation for various conduction disturbances. LVEF and global longitudinal strain measurements assessed by 2D special tracking echocardiography at baseline and at 1 month and 12 months follow up. Results At 12 months follow up, 14 (28%) patients developed PIVD; 4 of which developed pacemaker induced cardiomyopathy (PICM). At the one month follow up, the GLS was significantly reduced in the 14 patients who subsequently developed PIVD at 12 months, compared to those who did not show significant decline in EF. (n = 38) (GLS -12.46 ± 2.77 vs-16.05-± 2.57 vs. -16.4 respectively; p = 0.001). The ejection fraction was also significantly reduced in this group at 1 month follow up compared to those without PIVD (EF 53.57 ± 5.05 vs 61.28 ± 4.67 respectively; p value= 0.001) When the 4 patients with PICMP were excluded, only the 1-month GLS was significantly reduced compared to baseline. Conclusion: Global longitudinal strain measurements after pacemaker provides valuable data in predicting patients who subsequently develop pacemaker induced dysfunction.