Lau C P, Leung W H, Wong C K, Tai Y T, Cheng C H
Department of Medicine, University of Hong Kong, Queen Mary Hospital.
Am J Cardiol. 1990 May 15;65(18):1198-203. doi: 10.1016/0002-9149(90)90973-5.
In 15 patients with atrial fibrillation (AF), a single right ventricular extrastimulus (intercalated pacing) was delivered after every sensed conducted beat resulting in a reduction in rate. This method was used in 10 patients with lone AF and the average success rate of inducing coupling was 86 +/- 14% (range 64 to 100), using a mean coupling interval of 232 +/- 28 ms (range 175 to 290). During intercalated pacing, the pulse rate of AF was reduced (from 137 +/- 26 to 75 +/- 14 beats/min, p less than 0.001). Intercalated pacing resulted in enhancement of mean stroke volume (28 +/- 6 vs 44 +/- 10 ml in AF, p less than 0.0001), pulse pressure and the pulse-to-pulse regularity. Both the systolic and diastolic arterial pressures were regularized. The reduction in pulse rate during intercalated pacing was determined by the coupling interval, and the induction of concealed ventriculoatrial conduction (82 +/- 44 ms). Myocardial lactate extraction was similar during AF and short-term intercalated pacing (28 +/- 10 vs 25 +/- 9%, difference not significant). In 5 patients with severe mitral stenosis in AF, intercalated pacing resulted in an improvement in the cardiac output (3.1 +/- 0.2 vs 3.4 +/- 0.2 liters/min, p less than 0.04), a reduction in the gradient across the mitral valve (16 +/- 8 vs 10 +/- 5 mm Hg, p less than 0.02), and a reduction in pulmonary arterial and wedge pressures. This new pacing method thus achieved rapid temporary control of rate, regularity and cardiac hemodynamics during AF, which were more prominent in patients with mitral stenosis and restricted left ventricular filling.
在15例心房颤动（AF）患者中，在每次感知到的传导搏动后发放单个右心室额外刺激（插入式起搏），从而使心率降低。该方法用于10例孤立性AF患者，诱导耦联的平均成功率为86±14%（范围64%至100%），平均耦联间期为232±28毫秒（范围175至290毫秒）。在插入式起搏期间，AF的脉率降低（从137±26次/分钟降至75±14次/分钟，p<0.001）。插入式起搏导致平均每搏量增加（AF时为28±6毫升，起搏时为44±10毫升，p<0.0001）、脉压和逐搏规律性增强。收缩期和舒张期动脉压均变得规律。插入式起搏期间脉率的降低取决于耦联间期以及隐匿性室房传导的诱发（82±44毫秒）。AF期间和短期插入式起搏期间心肌乳酸摄取相似（28±10%对25±9%，差异无统计学意义）。在5例AF合并严重二尖瓣狭窄的患者中，插入式起搏使心输出量增加（3.1±0.2升/分钟对3.4±0.2升/分钟，p<0.04），二尖瓣跨瓣压差降低（16±8毫米汞柱对10±5毫米汞柱，p<0.02），肺动脉压和楔压降低。因此，这种新的起搏方法在AF期间实现了对心率、节律和心脏血流动力学的快速临时控制，在二尖瓣狭窄和左心室充盈受限的患者中更为显著。
