小剂量多巴酚丁胺超声心动图试验的临床研究

Clinical Study of Low-Dose dobutamine echocardiography

目的评价小剂量多巴酚丁胺超声心动图试验（ＬＤＤＥ）在急性心肌梗塞早期对心肌梗塞后局部左室功能改善的预测价值。方法对７１例急性心肌梗塞患者于发病后２周内行ＬＤＤＥ，观察静态、静注多巴酚丁胺（５、１０μｇ·ｋｇ－１·ｍｉｎ－１）及心梗后３个月局部室壁运动变化。结果ＬＤＤＥ发现静态时运动减弱节段的心肌存活比无运动节段更常见（分别为５０％和１５％，Ｐ＜０．０００１，优势比为５．２７，９５％可信区间为３．０２～９．２１）。静态时运动减弱节段在随访时局部功能改善比无运动节段更常见（分别为５０％和２３％，Ｐ＜０．０００１，优势比为３．３５，９５％可信区间为１．９８～５．６７）。以随访时节段局部功能改善作为心肌存活的参考标准，ＬＤＤＥ预测节段局部功能改善总的敏感性、特异性分别为７３％、９２％。根据ＬＤＤＥ时室壁运动反应分为心肌存活组（Ａ组，３１例）及无存活组（Ｂ组，４０例）。Ａ组随访时室壁运动指数较静态时下降（１．４６±０．３１降至１．２１±０．３０，Ｐ＝０．００１６），Ｂ组则无改变。随访时与静态时室壁运动指数差值绝对值Ａ组明显高于Ｂ组（分别为０．２５０±０．０１２与０．０６０±０．１０４，Ｐ＜０．０００１）。结论ＬＤＤＥ?

Objective This study was performed to detect viable myocardium using low-dose dobutamine echocardiography (LDDE) and evaluate the role of this method for predicting the improvement of regional left ventricular (LV) function in 71 patients with a first acute myocardial infarction (Q wave) within 2 weeks after onset of acute MI. Methods Regional wall motion was evaluated with 2dimensional echocardiography at rest, during dobutamine infusion (5,10μg·kg-1·min-1) and that at 3month followup. Results Viability of myocardium detected by LDDE was more frequent in hypokinetic segments than that in akinetic segments (50% vs 15%, P<0.0001,odds ratio 5.27, 95% confidence interval 3.02 to 9.21). Spontaneous recovery of mycardium at followup was more frequent in hypokinetic segments than that in akinetic segments (50% vs 23%, P<0.0001, OR 3.35, CI 1.98 to 5.67). Sensitivity and specificity of detecting viable segments by LDDE were 73% and 93%, respectively. Myocardial viability in the infarct zone by LDDE was documented in 31 patients(group A) and absent in 40 patients(group B).At followup, recovery of regional contractile function was observed in group A (RWMI decreased from 1.46±0.31 to 1.21±0.30; P=0.0016),but not in group B patients.Conclusion Lowdose dobutamine echocardiography can be safely performed to detect viable myocardium early after acute MI. It may predict improvement of regional left ventricular function with a high specificity.