急性心肌梗死超急性期的超声诊断

The value of diagnosis of the harmonic imaging ultrasonic integrated backscatter on the very early stage of acute myocardial infarction

目的研究急性心肌梗死（AMI）超急性期时的心肌组织超声背向散射积分（IBS）的变化及对临床诊断AMI超急性期的价值。方法将72例AMI患者分成2组：超急性期组（梗死时间在2h以内）30例，急性期组42例（梗死时间〉2h，有典型的心电图改变）；另取正常对照组30例。用HP-5500型超声诊断仪，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（IB％），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％）。同时作心电图的比较对照。结果当AMI超急性期组患者心电图还无典型变化时，心肌梗死部位的IBS值已明显大于正常人[（18．8±3．4）dB比（8．3±1．2）dB，P〈0．01]，而CVIB明显小于正常人[（6．3±0．7）dB比（7．6±1．1）dB，P〈0．01]。急性期组患者，其IBS明显高于正常人及患者本身非心肌梗死部位[（22．2±4．1）dB比（8．3±1．2）dB，（21．1±3．2）dB比（8．7±0．9）dB，P〈0．01]，而CVIB则明显低于正常人及患者本身非心肌梗死部位[（5．6±0．8）dB比（7．6±1．1）dB，P〈0．05；（5．8±0．7）dB比（9．3±0．9）dB，P〈0．01]。且与心电图的变化完全一致。结论心肌组织背向散射积分对临床上诊断AMI超急性期有很高的价值，并可判断病变心肌的范围和功能状况。

Objective To study change and the value of diagnosis of harmonic imaging ultrasonic integrated backscatter（IBS） on the very early diagnosis of acute myocardial infarction （AMI）. Method 72 patients were divided 2 groups, A group 30 cases with AMI at the very early stage of acute myocardial infarction （in 2 hours）, B group 42 cases with typical acute myocardial infarction （ in 2 - 12 hours） were examined by IBS and the cyclic variation of integrated backscatter （CVIB） with HP-5500 ultrasonic system in the segment of myocardial infarction and no myocardial infarction. Results In A group the IBS of the segment of AMI are very higher than that of the segment of no AMI[ （ 18.8 ± 3.4） dB vs （8.3 ± 1.2） dB,P 〈 0. 01 ], the CVIB are lower [ （6. 3 ± 0. 7） dB vs （7.6 ± 1.1 ）dB, P 〈 0. 01 ]. But in the meanwhile there are no obvious changes in ECG. In B group the IBS of the segment of AMI is obvious higher than the normal person and no infarction segment in the same heart [ （22. 2 ±4. 1）dB vs （8.3± 1.2）dB, （21.1 ±3.2）dB vs （ 8.7± 0. 9） dB, P 〈 0. 05 ], but CVIB is obvious lower than the normal person and no infarction segment in the same heart[ （5.6 ±0. 8）dB vs （7.6 ±1.1）dB, P〈0.05;（5.8±0. 7）dB vs （9.3 ±0.9）dB,P〈 0.01 ] ,the changes of the ultrasonic is coincidence with ECG. The change of IBS are very obvious just as in ECG. Conclusion The result demonstrate that ultrasonic tissue characterization with harmonic imaging integrated backscatter can be used for diagnosis the very early stage of AMI, and can judge the segment range of AMI and function of the whole heart.