超声背向散射积分对心肌梗死超急性期的临床诊断价值

目的研究心肌组织二次谐波成像背向散射积分（IBS）用于临床诊断心肌梗死超急性期的价值.方法选择30例正常人、12例心肌梗死超急性期患者（梗死时间在2 h以内）、36例典型急性心肌梗死患者（梗死时间在2～12 h,有典型的心电图改变）,应用超声于胸骨旁左室乳头肌短轴观,分别测量心肌梗死区域组织和非梗死区域心肌组织的IBS,并将其与心包IBS的比值作为心肌IBS的校正值（IB%）,舒张末期与收缩末期的IBS差值即IBS的周期变化（CVIB）,并将其与心包IBS的比值作为心肌CVIB的校正值（CVIB%）.同时记录心电图进行比较对照.结果12例心肌梗死超急性期患者心肌梗死部位的IBS值明显大于正常人（14.7对8.3,P＜0.01）,而CVIB明显小于正常人（6.1对7.6,P＜0.05）,此时心电图尚无典型变化.36例典型急性心肌梗死患者IBS明显高于正常人及患者本身非心肌梗死部位（21.3对8.3,20.2对8.5,P＜0.05）,而CⅥB则明显低于正常人及患者本身非心肌梗死部位（5.8对7.6,5.9对9.4,P＜0.05）,与心电图的变化完全一致.结论心肌组织IBS对临床上判断心肌梗死超急性期有很高的特异性和敏感性,并可判断病变心肌的范围和功能状况,可作为早期诊断心肌梗死超急性期的一个可靠指标.

Value of harmonic imaging diagnosis of very early stage of acute myocardial infarction by ultrasonic integrated backscatter

Objective To study the very early diagnosis of acute myocardial infarction (AMI) by harmonic imaging integrated backscatter(IBS).Methods Thirty normal persons,12 cases at the very early stage of AMI (in 2 hours),36 cases with AMI (in 2-12 hours) were examined by IBS and the cyclic variation of integrated backscatter (CVIB) with HP Sonos 5500 ultrasonic system in different areas (the areas of myocardial infarction and no myocardial infarction).Results In the areas of AMI of the very early stage (in 2 hours),IBS was much higher than that of the areas of normal (14.7 vs 8.3,P<0.01),CVIB was lower (6.1 vs 7.6,P<0.05).But at that time there were no obvious changes of AMI in ECG.In the other 36 cases with AMI the changes of the ultrasonic IBS were very obvious completely coincidence with ECG.IBS was obvious higher than normal person and no infracted areas of the patient himself (21.3 vs8.3,20.2vs8.5,P<0.05).But the CVIB was obvious lower than normal person and no infracted areas of the patient himself (5.8 vs 7.6,5.9 vs 9.4,P<0.05).Conclusions Ultrasonic tissue characterization with IBS can be used for diagnosis the very early stage of AMI,and can judge the area of AMI and function in the range of AMI.