小剂量多巴酚丁胺门控心肌显像预测左心室功能受损的冠心病患者CABG术后早期疗效

目的用小剂量多巴酚丁胺结合99mTc-甲氧基异丁基异腈(MIBI)门控心肌显像(SPECT)检测结果预测存活心肌在接受冠状动脉旁路移植术(CABG)的左心室功能受损的冠心病患者的疗效。方法对38例接受CABG的患者手术前行静息与小剂量多巴酚丁胺结合99mTc-MIBISPECT显像,术后3个月行静息SPECT随访。根据术后左心室射血分数(LVEF)与基线的变化,患者被分为2组:A组19人,术后LVEF值提高≥5%;B组19人,术后LVEF值提高<5%。结果A组术后LVEF值较基线提高(P<0.001),左心室舒张末期容积(EDV)、左心室收缩末期容积(ESV)明显缩小(P<0.05);B组术后LVEF、EDV、ESV值均无明显改善(P>0.05)。临床随访过程中B组有3位患者因心力衰竭再次住院治疗。以术后LVEF较基线提高≥5%作为标准,用ROC曲线得出多巴酚丁胺负荷试验过程中LVEF提高≥4.5%为预测值。多巴酚丁胺负荷试验过程中LVEF提高≥4.5%在A组中有10人,在B组中有3人。以多巴酚丁胺负荷试验过程中LVEF提高≥4.5%作为术后LVEF提高的标准,敏感度为76.9%,特异性为64%,准确性为68.4%。多巴酚丁胺负荷试验过程中LVEF与术后LVEF有明显相关性(r=0.83,P=0.000);多巴酚丁胺负荷试验过程中EDV、ESV与术后EDV、ESV有明显相关性(r=0.79,P=0.000,r=0.88,P=0.000)。结论小剂量多巴酚丁胺结合99mTc-MIBISPECT显像中LVEF提高≥4.5%可作为术后LVEF提高的预测指标。

Prognostic Value of Dobutamine ~(99m)Tc-MIBI SPECT in Early Stage Following Coronary Artery Bypass Grafts in Patients with Coronary Heart Disease and Left Ventricular Dysfunction

Objective Dobutamine ^99mTc-MIBI SPECT has been shown to enhance the detection of myocardial viability,this study evaluated its prognostic value in patients with coronary heart disease and left ventricular(LV) dysfunction after CABG.Methods Before CABG,38 patients(31 male,7 female;mean age was(66.5±7.0) years with LV dysfunction(42.7±12.5)% underwent the rest-dobutamine stressed ^99mTc-MIBI SPECT.The rest ^99mTc-MIBI SPECT follow up was performed 3 months later.Results(1) A post-revascularization improvement in ejection fraction(EF) ≥5% was defined as significant,patients were divided into tow groups:group A:LVEF increased significantly ≥5% in 19 patients at follow-up and group B:LVEF increased<5% in 19 patients.After CABG,LVEF in group A increased(P<0.001);end-diastolic volumes(EDV) and end-systolic volumes(ESV) decreased significantly(P<0.05);but LVEF,EDV and ESV had no change in group B.Three patients in group B had recurrent heart failure at follow-up.(2) According to receive-curve analysis,an increase in ejection fraction≥4.5% after dobutamine administration was the optimal cutoff value for predicting a significant postrevascularization improvement,with 76.9% sensitivity,64% specificity,and 68.4%accuracy.(3) A significant correlation was found between dobutamine and postrevascularization ejection fraction(r=0.83,P<0.001).The increase in ejection fraction during dobutamine administration is a good predictor of an improvement in ejection fraction after revascularization.Conclusion An increase in ejection fraction ≥4.5% during dobutamine ^99mTc-MIBI SPECT was the optimal cutoff value for predicting a significant postrevascularization improvement.