负荷-静息99Tcm-MIBI门控心肌灌注断层显像相位分析评价左室缺血心肌收缩同步性

Systolic synchrony of ischemic myocardium assessed by stress-rest 99Tcm-MIBI gated SPECT myocardial perfusion imaging

目的 以99 Tcm-MIBI门控心肌灌注断层显像（GSMPI）相位分析探讨不同缺血灌注状态下左室心肌收缩同步性.方法 回顾性分析129例[男65例,女64例,年龄48～88（68.6±10.2）岁]行99 Tcm-MIBI两日法静息-负荷GSMPI患者的心肌灌注及心功能数据.采用17节段5分制对图像进行评分,获得负荷总积分及心肌缺血积分,分为灌注正常组及灌注异常组,后者再分为可逆性灌注缺损组及固定性灌注缺损组.采用两独立样本t检验比较分析各组间GSMPI的PSD和PHB,各组内静息与负荷PSD及PHB间差异的比较采用配对t检验.结果 129例患者中,灌注正常组66例,灌注异常组63例,其中可逆性灌注缺损组39例,固定性灌注缺损组24例.灌注异常组PSD及PHB显著大于灌注正常组,分别为18.3±7.8和14.3±6.6,68.6±30.9和50.2±20.0（t=-3.110和-3.989,均P＜0.05）.尽管固定性灌注缺损组的PSD和PHB较可逆性灌注缺损组有增大趋势,但差异均无统计学意义（=-1.554～-0.408,均P＞0.05）;两亚组静息和负荷PSD和PHB间亦无明显差异（t=-0.961 ～-0.114,均P＞0.05）.LVEF≤60％组的静息和负荷PSD（20.4±8.1和20.8±6.4）均显著大于LVEF＞ 60％组（15.0±6.8和15.3±7.0;t=3.642和3.886,均P＜0.05）;LVEF≤60％组的静息和负荷PHB （77.8±53.5和78.4±26.7）也显著大于LVEF＞60％组（53.5±23.0和55.9±24.5;t=4.567和4.302,均P＜0.05）.结论 99Tcm-MIBI GSMPI相位分析能够反映血流灌注异常对心肌收缩同步性的损害及由此造成的对左室整体收缩功能的影响,可在一定程度上反映不同心肌缺血状态下左室收缩同步性的差异;就99Tcm-MIBI而言,负荷和静息GSMPI相位分析对左室收缩同步性评估的价值相当.

Objective To investigate the left ventricular synchrony under different ischemic statuses using phase analysis of 99Tem-MIBI gated SPECT MPI （GSMPI）.Methods The data of 129 patients （65 males,64 females,age：48-88 （68.6±10.2） years） who underwent 2-d stress-rest GSMPI were retrospectively analyzed.Perfusion images were scored by a 5-grade criteria （0-4） based on 17 coronary artery segments.Patients were divided into normal perfusion group （G1） and abnormal perfusion group （G2） according to the summed stress scores.G2 was divided into reversible perfusion defect subgroup （G2a） and irreversible perfusion defect subgroup （G2b） by the summed difference scores.The difference of PSD and PHB between groups and the difference between stress and rest GSMPI within each subgroup were compared using two-sample t test and paired t test,respectively.Results The numbers of patients in G1,G2,G2a and G2b were 66,63,39 and 24,respectively.The PSD （18.3±7.8） and PHB （68.6±30.9） of G2 were significantly higher than those （14.3±6.6 and 50.2±20.0） of G1 （t =-3.110,-3.989,both P〈0.05）.The PSD and PHB of G2b were higher than those of G2a,but the difference was not statistically significant （t：-1.554 to-0.408,all P〉0.05）,and the differences of PSD and PHB between rest and stress MPI within each subgroup were not significantly different （t：-0.961 to-0.114,all P〉0.05）.The PSD （20.4±8.1 and 20.8±6.4） and PHB （77.8±53.5 and 78.4±26.7） of rest and stress GSMPI in patients with LVEF ≤60%were significantly higher than those in patients with LVEF〉60%（15.0±6.8 and 15.3±7.0,53.5±23.0 and 55.9±24.5;t：3.642 to 4.567,all P〈0.05）.Conclusions 99Tcm-MIBI GSMPI phase analysis can show damage effect of abnormal myocardial perfusion on left ventricular synchrony,which influencing global left ventricular function,and it can show different left ventricular synchrony due to different degrees of myocardial ischemia.There is nearly same value of stress GSMPI and rest GSMPI in assessment of left ventricular synchrony.