Wang Daniel Y, Kelly Lauren A, Richmond Marc E, Quinn T Alexander, Cheng Bin, Spotnitz Michelle D, Cabreriza Santos E, Naka Yoshifumi, Stewart Allan S, Smith Craig R, Spotnitz Henry M
Departments of Medicine (Dr. Wang), Surgery (Drs. Naka, Smith, H. Spotnitz, M. Spotnitz, and Stewart, and Mr. Cabreriza and Ms Kelly), Pediatrics (Dr. Richmond), and Biostatistics (Dr. Cheng), Columbia University, New York, NY 10032; and National Heart and Lung Institute (Dr. Quinn), Imperial College London, Harefield Heart Science Centre, Harefield UB9 6JH, United Kingdom.
Tex Heart Inst J. 2013;40(4):403-9.
In selected patients undergoing cardiac surgery, our research group previously showed that optimized temporary biventricular pacing can increase cardiac output one hour after weaning from cardiopulmonary bypass. Whether pacing is effective after beating-heart surgery is unknown. Accordingly, in this study we examined the feasibility of temporary biventricular pacing after off-pump coronary artery bypass grafting. The effects of optimized pacing on cardiac output were measured with an electromagnetic aortic flow probe at the conclusion of surgery in 5 patients with a preoperative mean left ventricular ejection fraction of 0.26 (range, 0.15-0.35). Atrioventricular (7) and interventricular (9) delay settings were optimized in randomized order. Cardiac output with optimized biventricular pacing was 4.2 ± 0.7 L/min; in sinus rhythm, it was 3.8 ± 0.5 L/min. Atrial pacing at a matched heart rate resulted in cardiac output intermediate to that of sinus rhythm and biventricular pacing (4 ± 0.6 L/min). Optimization of atrioventricular and interventricular delay, in comparison with nominal settings, trended toward increased flow. This study shows that temporary biventricular pacing is feasible in patients with preoperative left ventricular dysfunction who are undergoing off-pump coronary artery bypass grafting. Further study of the possible clinical benefits of this intervention is warranted.
在部分接受心脏手术的患者中，我们的研究小组先前表明，优化的临时双心室起搏可在体外循环撤机后1小时增加心输出量。心脏不停跳手术后起搏是否有效尚不清楚。因此，在本研究中，我们探讨了非体外循环冠状动脉搭桥术后临时双心室起搏的可行性。在5例术前平均左心室射血分数为0.26（范围为0.15 - 0.35）的患者手术结束时，使用电磁主动脉血流探头测量优化起搏对心输出量的影响。房室（7个）和室间（9个）延迟设置按随机顺序进行优化。优化双心室起搏时的心输出量为4.2±0.7 L/分钟；在窦性心律时，心输出量为3.8±0.5 L/分钟。以匹配心率进行心房起搏时的心输出量介于窦性心律和双心室起搏之间（4±0.6 L/分钟）。与标称设置相比，优化房室和室间延迟有使血流量增加的趋势。本研究表明，对于术前左心室功能不全且接受非体外循环冠状动脉搭桥术的患者，临时双心室起搏是可行的。有必要进一步研究这种干预措施可能带来的临床益处。
