冠心病介入治疗前行实时心肌声学造影评价缺血或存活心肌的实用价值

Assessment of Viable Myocardium in Patients With Coronary Artery Disease Before Intervention by Real Time Myocardial Contrast Echocardiography

目的:探讨冠状动脉支架置入术前行实时心肌声学造影(RTMCE)评价存活心肌的临床应用价值。方法:对20例择期行经皮冠状动脉支架置入术的冠心病患者(病例组)和7例冠状动脉造影未见异常患者(对照组)分别于支架置入术前后行RTMCE检查及双嘧达莫负荷后RTMCE检查,分析心肌血流再灌注的时间-密度曲线形态及相应的心肌显像峰值强度(A)、曲线上升平均斜率(β)和局部心肌血流量(A·β),评估用药前后各指标的比值变化。结果:静息状态灌注正常的病变节段,负荷前A、β及A·β与正常心肌无显著差异,负荷后A、β及A·β储备值明显低于正常心肌,缺血心肌支架置入术后心肌灌注明显改善。静息状态灌注异常的病变节段,负荷前A、β及A·β明显低于正常心肌,负荷后A、β及A·β储备值明显低于正常心肌,缺血心肌治疗后心肌灌注较治疗前有改善,但仍明显低于正常心肌。结论:冠心病患者冠状动脉支架置入术前行RTMCE检查有助于筛选合适的病例进行血运重建,避免给患者造成不必要的损伤。

Objective：To study the necessity of real time myocardial contrast echocardiography （RTMCE）in assessing viable myocardium prior to intracoronary stent implantation. Methods：Twenty patients with coronary artery disease（CAD） by coronary angiography underwent elective intracoronary stent implantation ,and 7 healthy subjects were used as controls. RTMCE was performed before and after procedure. During the contrast agent infusion and incremental triggering, the power Doppler signals were analyzed and the scores were recorded according to the extent of contrast agent infusion. In addition, myocardial reperfusion was observed before and after dipyridamole injection. The time-amplitude curves,the maximal amplitude score A, the mean ascending slope of the curve β and the product of A ·β, the changes of the reserve of A,β and A ·β were analyzed using CUSQ software. Results：The ischemic segments with normal perfusion at rest,A,β and A ·β had no significant differences compared with normal myocardium, but the reserve of A, β and A ·β was reduced after stress . After procedure, reperfusion of ischemic myocardium was obviously improved. For the ischemic segments with abnormal perfusion at rest, A, β and A·β were significantly decreased before stress, and the reserve of A, β and A ·β was lowered after stress . After procedure,reperfusion of ischemic myocardium was obviously improved, but was still obviously lower than that of normal myocardium. Conclusion. RTMCE before intracoronary stent implantation is helpful for screening the candidates of ideal CAD patients.