摘要
Objective: Our study aimed to assess the 6 months effect of right ventricular apical (RVA) pacing on RV longitudinal systolic strain (LSS) using two-dimensional speckle tracking echocardiography (2D STE). Background: RVA pacing differs from the natural conduction through His-Purkinje fibers in having slower conduction velocity as well as altering the normal myocardial sequences of activation. Despite the fact that numerous studies have investigated the effects of RVA pacing on the LV, data on the effects on the RV function remain scarce. 2-D STE permits an objective and quantitative assessment of segmental and global myocardial function and has been validated against tagged MRI. We used 2-D STE to evaluate the RV LSS in response to RVA pacing. Methods: This case-control study was carried out on 60 subjects (30 patients implanted with DDD devices for 3rd degree AV block + 30 age and sex matched controls) in the period between February 2018 and February 2020 in the Cardiology Department, Faculty of Medicine, Menoufia University. The patients were evaluated 6 months after their implantation using conventional echo, M Mode, Doppler and 2D STE. 2D STE was used to identify the LSS of RV myocardial segments at the time of aortic valve closure. Statistical analysis was conducted using SPSS software v 20. Results: Results revealed that RVA pacing resulted in a statistically significant reduction of the global RV LSS in patients with DDD pacemakers vs controls (P Conclusion: RVA pacing reduces the RV free wall and the global RV LSS. Apical segments were the most affected.
Objective: Our study aimed to assess the 6 months effect of right ventricular apical (RVA) pacing on RV longitudinal systolic strain (LSS) using two-dimensional speckle tracking echocardiography (2D STE). Background: RVA pacing differs from the natural conduction through His-Purkinje fibers in having slower conduction velocity as well as altering the normal myocardial sequences of activation. Despite the fact that numerous studies have investigated the effects of RVA pacing on the LV, data on the effects on the RV function remain scarce. 2-D STE permits an objective and quantitative assessment of segmental and global myocardial function and has been validated against tagged MRI. We used 2-D STE to evaluate the RV LSS in response to RVA pacing. Methods: This case-control study was carried out on 60 subjects (30 patients implanted with DDD devices for 3rd degree AV block + 30 age and sex matched controls) in the period between February 2018 and February 2020 in the Cardiology Department, Faculty of Medicine, Menoufia University. The patients were evaluated 6 months after their implantation using conventional echo, M Mode, Doppler and 2D STE. 2D STE was used to identify the LSS of RV myocardial segments at the time of aortic valve closure. Statistical analysis was conducted using SPSS software v 20. Results: Results revealed that RVA pacing resulted in a statistically significant reduction of the global RV LSS in patients with DDD pacemakers vs controls (P Conclusion: RVA pacing reduces the RV free wall and the global RV LSS. Apical segments were the most affected.
