256 iCT对左心耳容积和功能的评价

Evaluation of the Volume and Function of Left Atrial Appendage with 256-Slice Spiral Computed Tomography

目的利用256 iCT冠状动脉成像多期相三维容积重组评价左心耳的容积和功能。方法选取本院40例行256层螺旋冠状动脉CTA检查结果阴性患者的影像资料;将原始扫描数据重组成10个时相（5%~95%,间隔10%）,于Philips EBW 4.5工作站测量各时相左心耳容积,观察左心耳在整个心动周期中容积的变化,确定其最大容积（LAAVmax）、最小容积（LAAVmin）,并计算左心耳排血量（LAAEV）、左心耳排空分数（LAAEF）。分析左心耳各参数间的相关性及其与个体常规指标的相关性。结果左心耳容积在整个心动周期中是不断变化的,期间有两次排空;65%~85%时相期间左心耳容积变化较小,接近其自然状态。LAAVmax与LAAVmin明显相关,并分别与身高、体重、体表面积相关;LAAEV与身高、体重、体表面积、LAAVmax、LAAVmin明显相关;LAAEF与LAAVmin呈明显负相关,与LAAVmax无关。结论 256 iCT冠状动脉成像多期相三维容积重组可以对左心耳的容积和功能进行评价,为临床提供重要参考。

Objective To assess the volume and function of left atrial appendage （LAA） by using 256-slice spiral CT coronary angiography with multi-phase three-dimensional volume rendering technique. Methods A total of 40 patients with negative 256-slice spiral CT coronary angiography were enrolled in this study. Using the raw data, ten phase sets of transversal images were reconstructed （ 5% - 95% with an interval of 10% ）. All images were reviewed to observe the change of LAA volume in the cardiac cycle and to measure the maximum and minimum volume of left atrial appendage （LAAVmax and LAAVmin） , left atrial appendage ejection volume （LAAEV） , and left atrial appendage ejection fraction （LAAEF） on a Philips EBW 4.5 workstation. The correlations between each other among all LAA parameters, and the cor- relations between LAA parameters and conventional physical indexes were statistically analyzed. Results During the whole cardiac cycle the LAA volume kept changing and the LAA emptied twice. During 65% - 85% of cardiac cycle the LAA volume changed slightly, approximate to its natural state. Obvious linear correlation existed between LAAVmax and LAAVmin, and both LAAVmax and LAAVmin had a positive correlation with patient＇ s height, weight, and body surface area （ r = O. 862, r = 0. 540, r = 0. 533 and r = 0. 588, r = 0. 449, r = 0. 407, respectively）. LAAEV bore a close relation- ship with patient＇ s height, weight, body surface area, LAAVmax and LAAVmin （ r = 0. 522, r = 0. 538, r = 0. 587, r = O. 946, r = 0.651, respectively）, while LAAEV had a negative relationship with LAAVmin （ r = - 0. 542） and had no re- lationship with LAAVmax （r = -O. 057）. Conclusion 256-slice spiral CT coronary angiography with multi-phase three- dimensional volume rendering technique is very helpful in evaluating the volume and function of LAA, providing important reference for clinical diagnosis and treatment.