RESUMO
BACKGROUND: Right ventricular (RV) apical pacing can induce both interventricular dyssynchrony and intraventricular dyssynchrony. Mechanical dyssynchrony after long-term RV apical pacing is associated with reduced left ventricular (LV) systolic function and deterioration in functional capacity. AIM: We aimed to identify the short-term effects of the pacemaker RV lead position on remodeling of LV systolic functions. PATIENTS AND METHODS: The study included 30 patients who presented with an indication of permanent pacing and who underwent permanent single- or dual-chamber pacemaker insertion: 15 patients with RV apical pacing (RV apex), and 15 patients with non-apical pacing (mid-septal). The two-dimensional (2D) speckle tracking imaging technique was used for quantification of global longitudinal function of the left ventricle and dyssynchrony evaluation before pacemaker implantation and after a 3-month follow-up. RESULTS: At the 3month follow-up, post-pacing 2D speckle tracking echocardiography revealed impairment of global longitudinal strain in all patients and intraventricular dyssynchrony was significantly increased in the apical location compared with the non-apical location (radial dyssynchrony: 108.67⯱ 11.68â¯ms vs. 80.53⯱ 8.17â¯ms, pâ¯< 0.001) with a greater difference (50.53⯱ 13.30â¯ms) in the apical location than in the non-apical location (29.87⯱ 6.64â¯ms, pâ¯< 0.001). CONCLUSION: In the short-term follow-up, 2D speckle tracking echocardiography showed more radial dyssynchrony in the apical location than in the non-apical location of RV lead. The RV septal pacing is a better alternative in terms of less dyssynchrony compared to RV apical pacing. Older age, higher percentage of pacing, and device type are prognostic factors for development of pacemaker-induced cardiomyopathy.