64排螺旋CT不同R-R间期间隔法在评估左心室功能中的对比研究

Comparative study of the assessment of left ventricular function with 64-slice spiral CT at different R-R intervals

目的探讨在使用多排螺旋CT评估左心功能时，采用不同R-R间期间隔会对统计结果产生怎样的影响。方法50例临床怀疑冠心病的患者，行64排螺旋CT冠状动脉血管造影检查。扫描结束后，将原始数据分别按照2％、5％、10％和15％的R—R间期间隔进行重建，所得数据导人工作站中，利用心功能分析软件，测量左心室舒张末期容积、收缩末期容积、每搏输出量和左室射血分数。以2％R-R间期间隔所得数据为标准，并利用统计软件，观察5％、10％和15％的R-R间期间隔重建的数据是否具有统计差异。结果5％、10％R-R间期间隔重建的数据会在一定程度上高估左心室收缩末期容积，同时低估舒张末期容积、每搏输出量和左室射血分数，但无显著性差异，均可用于左心功能评估；15％R-R间期间隔重建所得的四种心功能参数与2％间期之间形成明显差异，具有统计学意义，不能用于心功能的评估。结论以10％R-R间期重建评定心功能，工作量最小（仅为2％R-R间期重建1／5；5％R-R间期重建的1／2），虽然每搏输出量和左室射血分数会较实际情况略小，但无统计学差异，临床可以广泛应用。

Objective To evaluate left ventricular （LV） function with 64-slice spiral CT at different R-R intervals. Methods 50 patients with suspected coronary artery disease underwent 64-slice CT coronary angiography. The o- riginal data were reconstructed with the 2%, 5%, 10% and 15% R-R intervals. Left ventrieular end diastolic vol- ume （EDV）, end systolic volume （ESV）, stroke volume （SV） and left ventricular ejection fraction （LVEF） was measured at different R-R intervals. Results Left ventricular end-systolic volume is overestimated at 5 %, 10 % R- R interval, and left ventricular end diastolic volume, stroke volume and left ventricular ejection fraction is underesti- mated at 5%, 10% R-R interval. The data of 5%, 10% R-R interval with no difference that can be used for left heart functional assessment, and the data of 2%, 15% R-R interval with significant difference that can not be used for left heart functional assessment. Conclusion It is simple to assess cardiac function at 10% R-R interval, there is no significant difference in stroke volume and left ventricular ejection fraction.