心肌梗死患者超急性期心肌超声背向散射参数检测及其意义

Examination of myocardial ultrasonic backscatter parameters and its value in patients with super-acute phase of myocardial infarction

目的 应用心肌组织超声背向散射积分（IBS）分析健康人及心肌梗死患者超急性期的心肌运动变化及其意义.方法 将38例急性心肌梗死（AMI）患者于超急性期（梗死时间在2 h内）及急性期（梗死时间＞2 h,有典型的心电图改变）进行心肌超声背向散射参数检测,另设健康对照组25例.分别测量心肌梗死区域和非梗死区域心肌组织的心动周期时间平均背向散射积分（IBS）,并将其与心包IBS的比值作为心肌IBS的校正值（IBS%）,舒张末期与收缩末期的IBS差值即IBS的周期变化幅度（CVIB）,并将其与心包IBS的比值作为心肌CVIB的校正值（CVIB%）.同期作心电图、心肌酶谱及心肌肌钙蛋白I检测.结果 当AMI超急性期患者心电图还无典型变化时,心肌梗死部位的IBS值已经明显大于健康对照组[（43.7±10.8）dB比（22.6±4.6）dB,P＜0.01],而CVIB 明显小于健康对照组[（10.2±2.6）dB比（13.2±3.8）dB,P＜0.01].急性期患者其IBS明显高于健康对照组及患者非梗死部位,而CVIB明显小于健康对照组及患者本身非梗死部位.且与心电图变化完全一致.结论 心肌超声背向散射参数有助于AMI超急性期诊断,并可判断心肌病变的范围和程度.

Objective To study the changes and their value of ultrasonic myocardial integrated backscatter （IBS）in normal control and patients with super-acute phase of myocardial infarction. Methods There were 38 cases of acute myocardial infarction（AMI）patients in the super-acute phase（time 〈 2 h infarction）and the acute phase（infarction time 〉 2 h,typical ECG changes）for myocardial ultrasonic backscatter parameters detection,an additional 25 cases as healthy control group. The myocardial infarction region and non-infracted myocardial tissue region average duration of cardiac cycle of integrated backscatter（IBS）were measured,and IBS adjusted value （IBS%）was calculated as the ratio of myocardial IBS to the pericardium,the difference of IBS at end-diastolic and late systolic was used as cyclic variation of IBS（CVIB）. The ratio of IBS to pericardial CVIB was used as its adjusted value（CVIB%）. Over the same period for the electrocardiogram,myocardial enzymes and cardiac troponin I were measured. Results When ECG was not typically changed in patients with super-acute phase AMI,the IBS values significantly increased in the myocardial infarction region than the normal control group （43. 7 ± 10. 8）dB vs.（22. 6 ± 4. 6）dB,P 〈0.01）,and CVIB was significantly lower than that in the normal control group（10. 2 ±2. 6）dB vs.（13. 2 ± 3.8）dB,P 〈 0.01]. The IBS in the acute phase in patients was significantly higher than that in the normal control group and those non-infarcted areas,and CVIB was significantly lower than that in the normal control group and those in the non-infarcted areas. The changes were consistent with the ECG changes. Conclusions Ultrasonic backscatter parameters might be helpful for diagnosis of hyperacute period of AMI,and the determination of the scope and extent of AMI.