急性心肌梗塞运动异常的自发改善和小剂量多巴酚丁胺超声心动图试验的预测价值

The Predicting Value of Low-Dose Dobutamine Echocardiography for Spontaneous Functional Improvement of Dyssynergic Segments in Patients with Acute Myocardial Infarction

观察急性心肌梗塞运动异常节段功能的自发性改善 ,评价小剂量多巴酚丁胺 (Dob)二维超声心动图 (2 DE)试验的预测价值和安全性。 方法 :急性心肌梗塞患者 17例 ,于梗塞后 7～ 14(10± 3)天行基础 2 DE和小剂量 [5μg/ (kg· min)和 10μg/ (kg·min) ]Dob- 2 DE试验 ,6个月左右行 2 DE复查。用 16 -节段半定量分析法对左心室各节段收缩运动和增厚情况给予分级记分。观察随诊时运动异常节段收缩功能改善情况 ,并将试验时检出的存活心肌节段与此对比 ,计算小剂量 Dob- 2 DE试验预测急性心肌梗塞运动异常节段收缩功能自发改善的准确性 ,并评价其安全性。 结果 :17例首次急性心肌梗塞患者 134个异常节段中 ,5 1个节段 (38.1% )收缩功能有自发改善 ,小剂量 Dob[5μg/(kg· min)和 10μg/ (kg· min) ]2 DE试验对此预测的敏感性、特异性、阳性、阴性预测值和准确性分别为 80 .4%～88.2 %、83.1%～ 86 .7%、74.5 %～ 80 .4%、87.3%～ 92 .3%和 82 .1%～ 87.3% ,1例在 Dob 10μg时出现胸痛伴 ST段抬高。无运动节段功能自发改善率和 Dob- 2 DE预测敏感性比运动低下节段均显著为低 (19.2 %对 42 .3%和 40 .0 %～6 0 .0 %对 84.8%～ 91.3% ;P均 <0 .0 5 )。 结论 :1急性心肌梗塞异常节段中约 38.

Objective:To observe spontaneous functional improvement of dyssynergic segments in patients with acute myocardial infarction (AMI),and to evaluate the predicting value of low dose dobutamine (Dob) echocardiogrphy for the improvement. Methods:In 17 patients with first AMI,regional wall motion abnormality (RWMA) was evaluated at baseline and during a low dose[5 μg/(kg·min) and 10 μg/(kg·min)]Dob (Dob 5 and 10) stress 2DE test performed within 7～14 (a mean of 10±3) days after AMI,and at 6 month (a mean of 163±17 days) follow up.Left ventricular regional wall motion and thickening in each segment were graded and scored using a 16 segment model and semiquantitative analysis method.The viable myocardial segments detected were compared with the actual spontaneous functional improvement of corresponding segments to calculate the sensitivity,specificity,positive predicting value (PPV),negtive predicting value (NPV) and accuracy of the test in predicting spontaneous functional improvement. Results:Of 134 dyssynergic segments in 17 patients with AMI,51 segments (38 1%) showed spontaneous functional improvement at 6 month fellow up.The sensitivity,specificity,PPV,NPV and accuracy of Dob 5 and 10 2DE tests for predicting functional improvement in patients with AMI were 80 4% 88 2%,83 1% 86 7%,74 5% 80 4%,87 3% 92 3% and 82 1% 87 3%,respectively,and angina pectoris with ST segment elevation was induced in one patient during Dob 10 infusion.Besides,the rate of spontaneous functional improvement in akinetic segments and the sensitivities for its prediction with Dob 2DE test were both lower than those in hypokinetic segments (19 2% vs.42 3%,and 40 0% 60 0% vs.84 8% 91 3%;both p <0 05). Conclusion:①The spontaneous functional improvement can happen in 38 1% of dyssynergic segments after first AMI,and low dose[5 μg(kg·min)和10 μg/(kg·min)]Dob 2DE tests can accurately predict the improvement,with the possibility of induced ischemia of Dob 10 μg/(kg·min).②The spontaneous improvement rate and the sensitivity for its prediction with Dob 2DE test in akinetic segments are both lower than those in hypokinetic segments.