Voci P, Bilotta F, Scibilia G, Caretta Q, Mercanti C, Marino B
II Cattedra di Cardiologia, Università degli Studi La Sapienza, Roma, Italy.
Cardiologia. 1992 Feb;37(2):105-11.
This study evaluated the early effect of coronary artery bypass grafting (CABG) on left ventricular systolic function. Intraoperative echocardiography was performed in 32 patients with coronary artery disease and chronic, stable angina pectoris. Left ventricular short-axis images at mid-papillary muscle level were videotaped at similar loading conditions shortly after pericardiotomy and 28 +/- 5 min after weaning from cardiopulmonary bypass. Inotropic or vasodilator administration was avoided or suspended at least 5 min before echocardiography. The left ventricle was divided off-line into 8 segments. The ejection fraction and percent systolic wall thickening (PSWT) were calculated pre- and post-CABG. A total of 256 myocardial segments were analyzed. Any segment showing a preoperative PSWT of less than 30% was considered dysfunctional, while segments with a PSWT of greater than 30% were considered normal. After surgery, the PSWT in 162 dysfunctional segments (63%) increased from 11.8 +/- 8.9 to 24.3 +/- 14.3% (p less than 0.001). Conversely, a reverse trend was found in the remaining 94 normal segments (37%) with a decreasing PSWT from 46.2 +/- 13.8 to 33.4 +/- 14.8% (p less than 0.001). Ejection fraction also increased from 47.2 +/- 3.5 to 58.5 +/- 18.9% (p less than 0.05). Thus, CABG is followed by an immediate recovery of systolic function in dysfunctional myocardial segments, while compensatory hyperfunction is reduced in normal segments. These results indicate that the post-CABG improvement in PSWT is due to redistribution of coronary blood flow, rather than to pharmacological or hormonal influences. Intraoperative echocardiography is a useful technique to monitor left ventricular function during surgery.
本研究评估了冠状动脉旁路移植术（CABG）对左心室收缩功能的早期影响。对32例冠心病合并慢性稳定型心绞痛患者进行了术中超声心动图检查。在心包切开术后不久以及体外循环停机后28±5分钟，于相似的负荷条件下录制乳头肌水平的左心室短轴图像。在超声心动图检查前至少5分钟避免或停用正性肌力药物或血管扩张剂。离线将左心室分为8个节段。计算CABG前后的射血分数和收缩期室壁增厚百分比（PSWT）。共分析了256个心肌节段。术前PSWT小于30%的任何节段被视为功能异常，而PSWT大于30%的节段被视为正常。术后，162个功能异常节段（63%）的PSWT从11.8±8.9增加到24.3±14.3%（p<0.001）。相反，在其余94个正常节段（37%）中发现了相反的趋势，PSWT从46.2±13.8降低到33.4±14.8%（p<0.001）。射血分数也从47.2±3.5增加到58.5±18.9%（p<0.05）。因此，CABG后功能异常的心肌节段收缩功能立即恢复，而正常节段的代偿性高功能降低。这些结果表明，CABG后PSWT的改善是由于冠状动脉血流的重新分布，而非药物或激素影响。术中超声心动图是手术期间监测左心室功能的有用技术。
