Zhi Li-Da, Hua Wei, Zhang Shu, Shi Rong-Fang, Wang Fang-Zheng, Chen Xin
Division of Clinical Electrophysiology, Fuwai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China.
Chin Med J (Engl). 2004 Apr;117(4):516-20.
Right ventricular apical pacing has been reported to reduce cardiac performance. But there are few reports on the effects of dual chamber (DDD) pacing on cardiac function compared to sinus rhythm. In this study, we evaluated the effects of right atrial and ventricular DDD pacing on cardiac function and ventricular contraction synchrony using equilibrium radionuclide angiography.
Ten patients implanted with a right atrial and ventricular DDD pacemaker underwent equilibrium radionuclide angiography. The scintigraphic data were obtained during sinus rhythm and pacing rhythm. Cardiac function parameters were obtained semimanually. Phase analysis was used to study the ventricular activation sequence and ventricular synchrony.
The left ventricular 1/3 ejection fraction decreased significantly during pacing compared with that during sinus rhythm [(23.4 +/- 6.1)% vs (27.7 +/- 4.5)%, P = 0.01]. Regional ejection fraction also decreased during pacing, although the difference was not statistically significant. Phase analysis showed that the right ventricle was activated earlier than the left ventricle during pacing, and that the phase shift was significantly greater during pacing than that during sinus rhythm [64.13 degrees +/- 16.80 degrees vs 52.88 degrees +/- 9.26 degrees, P = 0.007]. The activation of both ventricles occurred simultaneously during sinus rhythm, with the activation sequence from proximal septum or base of left ventricle to apex. The earliest activation during pacing occurred at the right ventricular apex, and subsequently spread to the base and left ventricle.
Right atrial and ventricular DDD pacing impairs left ventricular systolic function and ventricular synchrony.
据报道，右心室心尖部起搏会降低心脏功能。但与窦性心律相比，关于双腔（DDD）起搏对心脏功能影响的报道较少。在本研究中，我们使用平衡放射性核素血管造影评估右心房和心室DDD起搏对心脏功能和心室收缩同步性的影响。
10例植入右心房和心室DDD起搏器的患者接受了平衡放射性核素血管造影。在窦性心律和起搏心律期间获取闪烁扫描数据。心脏功能参数通过半自动方式获得。相位分析用于研究心室激活顺序和心室同步性。
与窦性心律期间相比，起搏期间左心室1/3射血分数显著降低[（23.4±6.1）%对（27.7±4.5）%，P = 0.01]。起搏期间局部射血分数也有所下降，尽管差异无统计学意义。相位分析显示，起搏期间右心室比左心室更早激活，且起搏期间的相移显著大于窦性心律期间[64.13°±16.80°对52.88°±9.26°，P = 0.007]。窦性心律期间两心室同时激活，激活顺序从左心室近端间隔或底部至心尖。起搏期间最早的激活发生在右心室心尖部，随后扩散至底部和左心室。
右心房和心室DDD起搏会损害左心室收缩功能和心室同步性。
