SPECT门控心肌灌注显像相位图在冠状动脉慢性闭塞病变患者中的应用价值

Clinical value of gated MPI phase histogram in patients with chronic total occlusive coronary artery disease

目的分析冠状动脉慢性闭塞病变（CTO）患者SPECTG—MPI相位图，探讨其在CTO患者中的应用价值。方法回顾性分析2012年中国CTO俱乐部的21例CTO患者[均为男性，年龄37～77（平均56．6）岁]。患者术前完成^99Tc^m-MIBIG—MPI和^18F—FDG心肌代谢显像。应用G—MPI所测LVEF评价左心室功能，并将患者分为2组：正常组（11例，LVEF〉60％）和非正常组（10例，LVEF≤60％）。采用两样本t检验或Wilcoxon秩和检验比较2组患者的LVEF、灌注／代谢缺损、左心室收缩同步性参数，分析CTO患者中同步性参数[峰相位，相位标准差（SD），相位图带宽、偏斜及陡度]与LVEF的线性相关性。结果21例CTO患者闭塞时间为3—60个月，相位SD和相位图带宽均高于健康参考值，分别为（30．8±28．3）°与（14．2±5．1）°，t=3．09；（58．1±39．4）°与（38．7±11．8）°，t=2．61，均P〈0．05。这2个参数与LVEF均呈负相关（r=-0．785、-0．883，均P〈0．01），而相位图偏斜和陡度与LVEF均呈正相关（r=0．755、0.666，均P〈0．01）。正常组患者LVEF高于非正常组患者：（69．3±4．7）％与（44．7±13．0）％，t=-5．65，P〈0．01；灌注缺损比例低于非正常组：4．0％与16．0％；Z=-2．23，P〈0．05；代谢缺损比例差异无统计学意义（Z=-1．82，P〉0．05）。正常组相位SD及相位图带宽显著低于非正常组，分别为（18．7±19．0）°与（44．2±31．6）°，t=2．21；（36．4±12．7）°与（82．1±45．4）°，t=3．08，均P〈0．05。相位图偏斜、陡度正常组高于非正常组-5．11±0．75与3．55±1．05，t=-3．89；30．77±10．49与15．66±10．12．t=-3．35，均P〈0．01。结论CTO患者左心室收缩同步性较健康人差，核素显像相位图同步性参数可有效预测左心室泵功能。

Objective To evaluate the clinical value of phase diagrams in G-MPI for patients with chronic total occlusive coronary artery disease （CTO）. Methods Twenty-one CTO patients （all males, average age： 56.6 years, age range： 37-77 years） from CTO Club of China in 2012 were retrospectively analyzed. ^99Tc^m- MIBI myocardial perfusion and ISF-FDG myocardial metabolic imaging were performed. Patients were divided into normal group with LVEF〉60% （n= 11） and abnormal group with LVEF≤60% （n= 10）. Differences of LVEF, perfusion/metabolic deficit and synchrony were compared by two-sample t test or Wilcoxon rank sum test. Correlations between LVEF and synchrony were analyzed by linear correlation analysis in all CTO patients. The synchrony parameters included peak phase, phase standard deviation （ SD）, phase histogram bandwidth, skewness and kurtosis. Results The history of occlusion for the 21 patients ranged from 3 to 60 months. In all CTO patients, the phase SD and bandwidth were higher than the healthy reference values： （（30.8±28.3）°vs （14.2±5.1）°, t=3.09; （58.1±39.4）° vs （38.7±11.8）°, t=2.61, both P〈0.05）. LVEF was negatively correlated with the phase SD and bandwidth （r=-0.785, -0.883, both P〈0.01） but positively correlated with phase histogram skewness and kurtosis （r= 0.755, 0.666, both P〈0.01 ）. Higher LVEF value was shown in normal group than that in group（（69.3±4.7） % vs （44.7±13.0）%, t =-5.65, P〈 0. 01）. The perfusion deficit in normal group （4.0%） was lower than that in abnormal group （16.0%） （Z= -2.23, P〈0.05） while the metabolic deficit of the two groups was similar （Z=- 1.82, P〉0.05）. The phase SD and bandwidth were lower in normal group than those in abnormal group （（ 18.7±19.0）° vs （44.2±31.6）°, t=2.21; （36.4±12.7）° vs （82.1±45.4）°, t=3.08, both P〈0.05） and skewness and kurosis were higher in normal group than those in abnormal group （5.11±0.75 vs 3.55±1.05, t=-3.89; 30.77±10. 49 vs 15. 66±10.12, t=-3.35, both P〈0.01）. Conclusions The left ventricle synchrony was significantly worse in patients with CTO than that in normal individuals. The phase histogram could be used to estimate the the contractile function of left ventricle in the patients with CTO.