RESUMO
Objective To evaluate the effect of pacing in right ventricular outflow septal (RVOTs) or in right ventricular apex (RVA) on cardiac function in patients with sick sinus syndrome. Methods Sixty-two patients with sick sinus syndrome (SSS) were enrolled into the study. They were divided into AAI, RVOTs and RVA groups and implanted DDD/DDDR pacemakers in different pacing sites. The follow-up was ranged from 1 to 12 months after operation. Then we measured Tei index , E/E′and other parameters. And their difference in cardiac function and hemodynamic effect among different groups were compared. Results At 1 year post-operation there were significant differences in Tei index and E/E' among 3 groups (P < 0.05). LV and RV Tei index of RVOTs group was higher than that of AAI group , and LV and RV Tei indexes of RVA group were the highest among the three groups. E/E'of RVA group was the highest and in AAI group was the lowest. At 1 year post-operation LVEF and SV of AAI group were the highest, and those in RVA group were the lowest. The differences were statistically significant (P < 0.05). Conclusion Pacing in RVOTs in patients with SSS could offer better cardiac function and hemodynamics effect than pacing in RVA , but is still not better than atrial pacing.