Abstract: Objective: Managed ventricular pacing (MVP) and Search AV+ are representative dual-chamber pacing algorithms for minimizing ventricular pacing(VP). This study is to examine the difference in ability to reduce percentage of VP in patients of sick sinus syndrome who have been planted with pacemaker between these two algorithms. Methods: Subjects were randomly divided into the MVP group and Search AV+. The percentages of ventricular pacing of the patients were compared one month after planting pacemaker. Results: The median of percentages of VP were lower during the MVP operation than that during the Search AV+（0.3% vs 3.1%，P<0.01）. The percentages of atrial pacing have no significant difference between two groups. Conclusions: Managed ventricular pacing algorithm, compared with Search AV+, offers further percentage of VP reduction in patients of sick sinus syndrome with a dual-chamber pacemaker.

Key words: pacemaker, minimizing ventricular pacing, managed ventricular pacing, sick sinus syndrome, atrioventricular block