Self-control Trial Of AAISafeR Pacing Mode

BackgroundIt was 50 years since cardiac pacemaker used in clinic. Keeping the heart rhythm regular,the hydrodynamics stable and the blood circulation normal are the most essential function of cardiac pacemaker. People are always making their efforts to gain the best physiological effects from optimizing different pacing modes,which include atrioventricular synchronization,cardiac chronotropic pacing and ventricular synchronization. Obviously , these optimized pacing mode make the cardiac pacemaker more effectively used in clinic.However,many multi-centres international clinical trails have indicated that it is hazard in ventricular pacing,which increased the incidence rate of atrial fibrillation and heart failure. So,how to reduce ventricular pacing will become focal point recently.The pacemaker with mode of AAIsafeR can work with AAI normally. Once the intrinsic ventricualr activity was founded disappearing,the pacemaker will alter to pace with mode of DDD rapidly to ensure the safety of patients. At presen,it have not correlation research about clinical application of AAIsafeR in china. So,we carry out the study to verification its effct.ObjectiveTo analyse the relationship of cardiac structure and function with cumulative percent ventricular pacing (Cum%VP) in patients implanted with Symphony 2450. MethodsTo observe the Changes of L AD,LVEDV,LVESV and LVEF with different pacing mode(DDD,AAISafeR) in 42 patients with single-blind,randomized and self-control controlled principle.ResultAfter following-up 3-month with different pacing mode separately,the diameter of LA was diminution,the diameter of LV and LVEF did not changed. Comparison with DDD mode,the cum%VP in AAISafeR mode had significant difference .ConclusionThe mode of AAIsafeR could diminish the Cum%VP obviously and minimumlize the harmless of right entricular pacing.