小剂量多巴酚丁胺超声心动图试验和双核素心肌显像检测急性心肌梗死后患者存活心肌比较

Comparision of low-dose dobutamine echocardiography and dual-isotope emission simultaneous myocardial perfusion acquisition for myocardial viability assessment

目的比较小剂量多巴酚丁胺超声心动图试验(LDDE)和^(99)Tc-甲氧基异丁腈(MIBI)/^(18)F-脱氧葡萄糖(FDG)双核素同时采集法(DISA)单光子发射型断层显像(SPECT)对急性心肌梗死早期存活心肌检出的准确性。方法对44例急性心肌梗死患者于发病后5～10天内行 LDDE和 DISA-SPECT,所有患者在 LDDE 和 DISA 检查后接受经皮冠状动脉介入术。两种方法均采用16节段半定量法分析图像。心肌梗死后3个月随访二维超声,以局部室壁运动改善作为心肌存活标准,比较两种方法检测存活心肌的敏感性和特异性。结果 LDDE 检出存活心肌的敏感性、特异性、诊断准确性、阳性预测值和阴性预测值分别为77%、82%、79%、82%和77%。DISA 检出存活心肌的敏感性、特异性、诊断准确性、阳性预测值和阴性预测值分别为85%、62%、74%、71%和79%。LDDE 和DISA 两者对运动异常节段检出存活心肌的一致性为70%。对于运动减低节段,LDDE 和 DISA 对存活心肌检出率差异无统计学意义(74.1%比77.6%,P>0.05);对于无运动节段,LDDE 对存活心肌检出率低于 DISA(29%比53%,P<0.01)。结论对急性心肌梗死后的患者,DISA 检出存活心肌的敏感性高于 LDDE,而特异性低于 LDDE,联合应用起互补作用,提高检测存活心肌的能力。

Objective To compare the value of low-dose dobutamine echocardiography （LDDE） and dual-isotope emission simultaneous myocardial perfusion acquisition （technetium-99-m-tetrofosmin/ fluorine 18-fluorodeoxy-glucose ） single-photon emission computed tomography （DISA-SPECT） for myocardial viability assessment in patients with acute myocardial infarction （ MI）. Methods LDDE and DISA-SPECT were performed in 44 patients within 5-10 days after onset of first acute MI and percutaneous coronary intervension was made thereafter. A 16-segment semi-quantitative scoring model was adopted for both techniques. Wall motion improvement at follow-up （3 months after acute MI） compared with baseline before dobutamine infusion derived from two dimensional images was used as golden criteria for myocardial viability. Results The sensitivity, specificity, diagnostic accuracy, positive and predictive values for identification of viable myocardium were 77% ,82% ,79% ,82% and 77%, respectively by LDDE and 85%, 62% ,74% ,71% and 79%, respectively by DISA. No difference was found between LDDE and DISA for identifying viable myocardium in hypokinetic segments （74. 1% vs. 77.6%, P 〉 0. 05 ） but less viable myocardium was detected by LDDE than DISA in akinetic segments （ 29% vs. 53%, P 〈 0. 01 ）. Conclusions Sensitivity was higher while specificity was lower on detecting viable myocardium by DISA compared to LDDE. Combined use of the two techniques could improve viable myocardium detection in patients with acute MI.