门控心肌灌注断层显像相位分析评价健康人左室心肌收缩同步性

摘要

Objective To investigate the value of Cedars-Sinai quantitative gated SPECT (QGS) phase analysis for left ventricular synchrony assessment in healthy subjects.Methods Seventy-four healthy subjects (41 males,33 females,average age:(60±13) years) underwent both rest and exercise 99Tcm-MIBI G-MPI.QGS software was used to analyze the reconstructed rest gated SPECT images automatically,and then the parameters of left ventricular synchrony including phase bandwidth (BW) and phase standard deviation (SD) were obtained.The influences of gender and age (age＜60 years,n =36; age ≥ 60 years,n =38) on left ventricular systolic synchronicity were analyzed.The phase angle for original segmental contraction was measured to determine the onset of the ventricular contraction using 17-segment model.Forty healthy subjects were selected by simple random sampling method to evaluate the intra-observer and interobserver repeatability of QGS phase analysis software.Two-sample t test and linear correlation analysis were used to analyze the data.Results The BW and SD of left ventricular in healthy subjects were (37.22 ±11.71)°,(11.84±5.39)° respectively.Comparisons between male and female for BW and SD yielded no statistical significance (BW:(36.00±9.70)°,(38.73±13.84)°; SD:(11.88±5.56)°,(11.79±5.26)°; t=0.96 and-0.07,both P＞0.05) ; whereas the older subjects (age≥60 years) had larger BW than the others (age＜60 years ; (39.95± 12.65) °,(34.33± 10.00) ° ; t =-2.11,P＜0.05) and no statistical significance was shown for SD between the two age groups ((11.18±4.31) °,(12.54±6.33) ° ; t =1.08,P＞0.05).Of the 74 subjects,the mechanical activation started from the ventricular base to apex in 54 subjects (73％),and from apex to base in only 20 subjects (27％).High repeatability of phase analysis was observed for both intra-observer and inter-observer (r=0.867-0.906,all P＜0.001).Conclusions Good left ventricular segmental synchrony is shown in healthy subjects.No gender difference exists for ventricular synchrony assessment.Age (＜60 years) is important for better synchrony.Cedars-Sinai QGS cardiac phase analysis software is valuable in quantitative assessment of left ventricular synchrony with high repeatability.%目的 应用美国Cedars-Sinai定量门控心肌断层显像(QGS)软件的相位分析技术定量分析健康人左室心肌收缩同步性.方法 对74名健康人[男41名,女33名,平均年龄(60±13)岁]进行运动-静息99Tcm-MIBI G-MPI.应用QGS软件对重建后的静息图像进行自动分析,获得左室心肌收缩同步性参数:相位直方图带宽(BW)和相位标准差(SD),比较不同性别及年龄组(＜60岁组,36名；≥60岁组,38名)间左室心肌收缩同步性的差别.测量左室17个节段的起始相位角度,确定左室心肌最早收缩部位,简单随机抽样选择40名受检者评价QGS软件相位分析技术在同一操作者和不同操作者间的重复性.数据分析采用两样本t检验和直线相关分析.结果 74名受检者左室BW和SD值分别为(37.22±11.71)°和(11.84±5.39)°.男性和女性BW及SD值差异均无统计学意义[BW:(36.00±9.70)°和(38.73±13.84)°；SD:(11.88±5.56)°和(11.79±5.26)°；t=0.96和-0.07,均P＞0.05).年龄≥60岁组较年龄＜60岁组BW宽[(39.95±12.65)°和(34.33±10.00)°；t=-2.11,P＜0.05]；但2年龄组间SD差异无统计学意义[(11.18±4.31)°和(12.54±6.33)°；t=1.08,P＞0.05].74名受检者中,54名(73％)左室心肌收缩从基底部向心尖部扩散,仅20名(27％)由心尖部向基底部扩散.同一操作者2次操作及2名操作者间相位分析结果均相关(r=0.867～0.906,均P＜0.001).结论 健康人左室心肌收缩同步性良好,不同性别间无明显差异,年龄＜60岁者心肌收缩同步性较≥60岁者更好.QGS心脏相位分析软件是可定量评价左室心肌收缩同步性的工具,且重复性好.