双源CT冠状动脉成像的重建时相及其与心率的相关性

Reconstruction phases of dual-source CT coronary angiography and correlation with heart rate

目的探讨双源CT(DSCT)冠状动脉成像的最佳重建时相及其与心率的相关性。方法 163例患者接受DSCT冠状动脉成像检查,选择自动化最佳舒张期和最佳收缩期重建模式,按美国心脏协会(AHA)分类指南将冠状动脉树分为15个节段,分3级评价图像质量。分析冠状动脉成像重建的最佳舒张期和最佳收缩期时相位置,采用Pearson相关分析评价其与心率的相关性。结果 163例患者平均心率为(69.3±14.6)次/分,冠状动脉成像重建的最佳舒张期时相为(75.5±4.6)%R-R间期,最佳收缩期时相为(36.4±4.5)%R-R间期;最佳舒张期、最佳收缩期时相的位置与心率分别存在相关性(r=0.307、0.579,P均<0.05);单一最佳时相重建时,总体冠状动脉图像质量得分为(1.06±0.22)分。结论 DSCT冠状动脉成像质量存在两个高峰期,即舒张中期和收缩中晚期;随着心率的增高,最佳舒张期时相位于舒张中期越晚的时相,最佳收缩期时相位于收缩中晚期越晚的时相。

Objective To evaluate the correlation of reconstruction phases and heart rate（HR）in patients undergoing dual-source CT（DSCT）coronary angiography.Methods A total of 163 patients underwent contrast-enhanced DSCT coronary angiography.Datasets of best diastolic phase（BDP）and best systolic phase（BSP）were reconstructed automatically.The image quality was assessed using a three-point scale according to the AHA criteria.Pearson correlation analysis was used for statistical procession.Results During scanning,the mean heart rate was（69.3±14.6）bpm.BDP was at（75.5±4.6）% R-R intervals,and BSP was at（36.4±4.5）% R-R intervals.Positive correlation was found between HR and BDP（r=0.307,P〈0.05）,also between HR and BSP（r=0.579,P〈0.05）.The mean score of the whole coronary in the optimal reconstruction phase was 1.06±0.22.Conclusion In DSCT coronary angiography,the best image quality can be obtained both in mid-diastole intervals and mid-late systole intervals.With the increase of HR,BDP appears more often in the later phase in mid-diastole intervals,and BSP appears more often in the later phase in mid-late systole intervals.