摘要目的 应用单光子发射计算机断层成像(SPECT)/CT门控心肌灌注显像(GMPI)相位分析技术评价陈旧性心肌梗死(OMI)患者的左心室收缩同步性,并探讨影响收缩不同步的独立危险因素.方法 选择2010年10月至2013年9月在常州市第一人民医院确诊的OMI患者76例作为OMI组,同时选择健康者74例作为对照组,对其临床资料进行回顾性分析.所有研究对象均进行静息GMPI检查,应用Cedars Sinai QGS软件相位分析技术获得左心室收缩同步性参数[相位直方图带宽(BW)和相位标准差(SD)]以及心功能参数,应用QPS软件获得心肌灌注缺损范围.分别比较OMI组与对照组、左心室射血分数(LVEF)≤35％与LVEF＞ 35％ OMI患者之间的BW和SD值.以对照组BW值的x-±2s为异常临界阈值,大于该阈值定义为左心室收缩不同步,分析其独立危险因素.结果 (1)OMI组的BW[(91.3 ±58.6)°比(37.2±11.7)°,P＜0.001]和SD值[(27.3±20.8)°比(1 1.8±5.4)°,P＜0.001]均高于对照组,LVEF低于对照组(P＜0.001).LVEF≤35％的OMI患者BW[(136.0±52.9)°比(51.0±24.0)°,P＜0.001]和SD值[(38.7±21.3)°比(17.1±14.0)°,P ＜0.001]均高于LVEF＞ 35％的OMI患者.(2)在OMI患者中,左心室收缩不同步(BW ＞60.6°)的比例为57.9％ (44/76).与左心室收缩同步性正常OMI患者比较,不同步患者的LVEF较低(P＜0.0O1),左心室舒张末期容积、收缩末期容积、室壁运动异常总积分、室壁增厚异常总积分和心肌灌注缺损范围均较高(P均＜0.001).(3)LVEF≤35％的OMI患者合并左心室收缩不同步的比例高于LVEF＞35％的患者[91.7％ (33/36)比27.5％ (11/40),P＜0.001].(4)Pearson线性相关分析显示,LVEF与BW呈负相关(r=-0.807,P＜0.001).(5)多因素logistic回归分析显示,心肌灌注缺损范围是导致OMI患者发生左心室收缩不同步的独立危险因素(OR=1.076,95％ CI:1.015 ～1.141,P=0.015).结论 GMPI相位分析可客观反映左心室收缩同步性;OMI患者左心室收缩同步性减低,左心室收缩不同步与LVEF相关;心肌灌注缺损范围是OMI患者发生左心室收缩不同步的独立危险因素.

abstractsObjective To assess the left ventricular (LV) systolic synchrony by phase analysis of gated myocardial perfusion imaging (GMPI) with SPECT/CT in patients with old myocardial infarction (OMI) and further to identify independent predictors for LV dyssynchrony.Methods Seventy-six OMI patients and seventy-four healthy volunteers (control group) underwent resting GMPI from October 2010 to September 2013 in our hospital were included in this study.The left ventricular systolic synchrony parameters including phase histogram bandwidth (BW) and phase standard deviation (SD) were obtained by Cedars-Sinai quantitative gated SPECT (QGS) phase analysis technique,and LV cardiac function was also measured.The extent of myocardial perfusion defect was analyzed by the Quantitative Perfusion SPECT (QPS) software.The value of BW and SD were compared between OMI and the control groups,between LVEF ≤ 35％ and LVEF ＞ 35％ groups in OMI patients.Dyssynchrony was defined when the BW exceeded the abnormality threshold derived from a normal control group (threshold =x-± 2s for normal BW).Results (1) TheBW ((91.3±58.6)°vs.(37.2 ±11.7)°) and SD ((27.3 ±20.8)° vs.(11.8± 5.4) °) were significantly higher and the LVEF was significantly lower in OMI group than in the normal controlgroup (all P ＜0.01).In addition,BW ((136.0 ± 52.9)° vs.(51.0 ± 24.0)°) and SD ((38.7 ± 21.3) ° vs.(17.1 ± 14.0)°) were significantly higher in patients with LVEF ≤ 35％ than in patients with LVEF ＞ 35％ (all P ＜ 0.001).(2) Dyssynchrony (BW ＞ 60.6°) prevalence was 57.9％ (44/76) in OMI patients.Compared with the synchrony group,LVEF was significantly lower,while the left ventricular end-diastolic volume,end-systolic volume,summed motion score,summed thickening score and extent were significantly higher in dyssynchrony group (all P ＜ 0.001).(3) Additionally,dyssynchrony prevalence was significantly higher in patients with LVEF≤35％ compared with patients with LVEF ＞ 35％ (91.7％ (33/36) vs.27.5％ (11/40),P ＜0.001).(4) Pearson correlation analysis showed that LVEF was negatively correlated with BW (r =-0.807,P ＜ 0.001).(5) Multivariate logistic regression analysis revealed that the extent of myocardial perfusion defect was an independent predictor for dyssynchrony in OMI patients (OR =1.076,95％ CI:1.015-1.141,P =0.015).Conclusions GMPI phase analysis can reliably reflect left ventricular systolic synchrony.The left ventricular systolic dyssynchrony in OMI patients is significantly increased.Left ventricular dyssynchrony is closely related to LVEF.The extent of myocardial perfusion defect (Extent) is an independent predictor for left ventricular systolic dyssynchrony in OMI patients