Abstract
Changes in left ventricular global and regional longitudinal strain during right ventricular pacing
Author(s): Alaa Solaiman Algazzar, Azza Ali Katta, Kahled Said Ahmed, Nasima Mohamed Elkenany & Maher Abdelaleem EbrahimBackground: LV strain and functions may be altered by Right ventricular apical pacing (RVAP). Right ventricular Septal pacing (RVSP) might be a better alternative. The detrimental effect of RV pacing may be mediated by regional LV impairment. Objectives: Our study aimed to demonstrate the short term impacts of right ventricular (RV) apical and septal pacing on Left ventricular (LV) regional and global longitudinal strain (GLS) in patients with preserved ejection fraction (EF). Methods: 62 patients indicated for permanent pacemaker implantation and preserved LV systolic function were included. Dual chamber pacemakers were implanted in all patients. Patients were divided into 2 groups according to RV lead position: group A (RVAP, n = 32) and group B (RVSP, n = 30). Patients were examined at baseline and after 6 months of implantation for LV systolic functions, global and regional strain by echocardiography and 2D speckle tracking echocardiography. Results: Paced-QRS duration was significantly shorter in group B compared to group A patients (P value 0.02). Regarding ventricular strain, there were no statistically significant difference between both groups at baseline measurements in comparisons of GLS, relative apical longitudinal strain (rALS) and regional longitudinal strain (RLS) (P value of >0.05). In contrast there was statistically significant difference between both groups appeared in results of GLS (P value of 0.01) at 6 months. In addition, regional longitudinal strain in septal, apical and rALS were affected after 6 months with P value of 0.02, 0.03 and 0.03 respectively. Conclusion: RVAP appears to worsen global longitudinal strain more than RVSP, and the resultant decrease in apical strain is most correlated region to decrease in GLS.