Alfieri O, La Canna G, Giubbini R, Pardini A, Zogno M, Fucci C
Division of Cardiac Surgery, Civic Hospital, Brescia, Italy.
Eur J Cardiothorac Surg. 1993;7(6):325-30; discussion 330. doi: 10.1016/1010-7940(93)90175-b.
Recovery of myocardial contraction represents an important target of coronary revascularization and the preoperative recognition of viable akinetic (hibernating) myocardium is a crucial point of the preoperative investigation of patients with chronically depressed left ventricular function. In 14 patients dobutamine infusion during echocardiography was utilized to evoke the contractile reserve retained by viable akinetic segments. Redistribution of thallium(TI)-201 after the rest injection was also used to assess the viability of akinetic areas. The wall motion response to dobutamine infusion predicted immediate postoperative improvement in 85 of 93 segments (sensitivity 91.3%) and identified 25 of the 32 segments which did not exhibit early postoperative improvement (specificity 78.1%). Rest redistribution of TI-201 demonstrated high sensitivity (93.0%) but low specificity (43.7%) for predicting the early recovery of regional wall motion. When late recovery was also considered, the specificity of this method increased to 64.0%. Rest distribution of TI-201 identifies viability which is not necessarily associated with the early recovery of function postoperatively. When the echo-dobutamine test is positive, on the other hand, the recovery of function usually occurs immediately after revascularization and the operative risk is expected to be low even in the presence of severely compromised left ventricular function.
心肌收缩功能的恢复是冠状动脉血运重建的一个重要目标，术前识别存活的运动减弱（冬眠）心肌是术前评估左心室功能长期受损患者的关键点。在14例患者中，超声心动图检查期间使用多巴酚丁胺输注来激发存活运动减弱节段保留的收缩储备。静息注射后铊（TI）-201的再分布也用于评估运动减弱区域的存活情况。多巴酚丁胺输注后的室壁运动反应预测了93个节段中85个节段术后立即改善（敏感性91.3%），并识别出32个术后未早期改善节段中的25个节段（特异性78.1%）。TI-201静息再分布在预测局部室壁运动早期恢复方面显示出高敏感性（93.0%）但低特异性（43.7%）。当考虑延迟恢复时，该方法的特异性增加到64.0%。TI-201静息分布识别出的存活情况不一定与术后功能早期恢复相关。另一方面，当超声多巴酚丁胺试验呈阳性时，功能恢复通常在血运重建后立即发生，即使在左心室功能严重受损的情况下，手术风险预计也较低。
