双源CT与3.0T MRI比较评估不同时相的左心房容积和功能

目的 与3.0 T MRI比较,探讨双源CT(DSCT)评估心动周期中不同时相左心房容积和功能的能力.方法 回顾性分析行冠状动脉CTA检查的49例患者,同一天完成DSCT和MR检查,并获得DSCT容积数据及左心房垂直长轴和左心室短轴快速稳态平衡进动序列(FIESTA)电影图像.分析左心房不同时相容积并计算左心房功能指标,所有的左心房功能指标都经体表面积校正.通过线性相关和Bland-Altman分析评估DSCT和MR电影(CMR)两种检查方法间的相关性和一致性.结果 DSCT与CMR测量的体表面积校正参数分别为:最大左心房容积(LAVmax):(47.4±11.1)和(46.2±9.7)ml/m2；最小左心房容积(LAVmin):(22.2±6.9)和(21.3±5.8) ml/m2；P波对应的左心房容积(LAVp):(34.8±8.8)和(33.6±7.8) ml/m2；左心房存储容积(LARV):(24.0±5.7)和(21.5±5.0) ml/m2；左心房被动收缩容积(LAPV):(11.6±3.9)和(10.9±3.9)ml/m2；左心房主动收缩容积(LAAV):(12.4±3.9)和(10.7±3.6) ml/m2；左心房管道容积(LACV):(22.6±8.4)和(21.0±6.4)ml/m2；左心房射血分数(LAEF):(52.8±7.4)％和(54.5±6.3)％；DSCT与CMR测值之间的相关性分别为:0.89、0.90、0.90、0.80、0.82、0.80、0.76和0.78(P值均＜0.01).但DSCT高估了校正后的LAVmax、LAVmin、LAVp、LARV、LAPV、LAAV和LACV,其高估的偏差分别为1.2、0.9、1.1、0.3、0.1、0.2和0.4 ml/m2.与CMR相比,DSCT稍微低估了LAEF约0.6％.对左心房功能指标的测量,DSCT操作者间的差异低于CMR操作者间的差异(P＜0.05).结论 DSCT对心动周期内不同时相左心房的容积和功能的评估较准确、重复性较强,可为临床提供冠状动脉以外的信息.

Assessment of left atrial volume and function with dual-source CT: comparison with 3.0 T MRI

Objective To assess the performance of dual-source CT (DSCT) for left atrial volume and function evaluation and compare this performance to that of cardiac cine MR ( CMR ),which was considered as the standard reference technique.Methods Forty-nine patients referred for CT coronary angiography were enrolled in this study.DSCT data sets and FIESTA cines of the vertical long axis covering the left atrium and the short axis covering the left ventricle were obtained on the same day without additional medicine.All images were analyzed to obtain left atrial volume at different time and its function values.All the parameters were corrected by body surface area.Inter-modality agreement was tested through linear regression and Bland-Altman analyses.Repeated measurements were performed to determine inter-observer variation.Results The indexed measurements of DSCT and CMR were (47.4 ± 11.1 ) and (46.2 ± 9.7 )ml/m2 for LAVmax,( 22.2 ± 6.9) and ( 21.3 ± 5.8 ) ml/m2 for LAVmin,( 34.8 ± 8.8 ) and ( 33.6 ± 7.8 )ml/m2 for LAVp,(24.0 ±5.7)and(21.5 ±5.0) ml/m2 for LARV,(11.6 ±3.9)and(10.9 ±3.9) ml/m2 for LAPV,(12.4 ±3.9)and(10.7 ±3.6) ml/m2 for LAAV,(22.6 ±8.4)and(21.0 ±6.4) ml/m2 for LACV,(52.8 ± 7.4) ％ and ( 54.5 ± 6.3 ) ％ for LAEF,respectively.The correlation coefficients between DSCT and CMR measurements for LAVmax,LAVmin,LAVp,LARV,LAPV,LAAV,LACV and LAEF were 0.89,0.90,0.90,0.80,0.82,0.80,0.76 and 0.78,respectively.However,DSCT slightly overestimated LAVmax,LAVmin,LAVp,LARV,LAPV,LAAV and LACV,and the deviation was 1.2,0.9,1.1,0.3,0.1,0.2 and 0.4 ml/m2,respectively.Compared with CMR,DSCT slightly underestimated LAEF of about 0.6％.Interobserver variation was lower in DSCT examination than CMR for the measurements of left atrial function.ConclusionDSCT provided accurate and reproducible measurements of left atrial volume and function.