主动脉缩窄术后磁共振脉搏波传导速度法评估主动脉顺应性

目的 使用磁共振脉搏波传导速度法(PWV)评估主动脉缩窄(CoA)术后主动脉顺应性.方法 回顾性分析22例CoA术后患儿心脏磁共振,使用MRI相位对比序列测量并计算主动脉PWV,同时期行超声心动图测量双侧心室功能及心肌厚度.另选取年龄、性别匹配的22例健康儿童组成对照组测量主动脉PWV.结果 研究组平均PWV明显高于对照组(4.42±3.02)m/s vs(2.73±0.76)m/s,P=0.02].在研究组中,吻合口中度狭窄患儿PWV值最高,受试者工作特征(ROC)曲线分析发现,取PWV为3.37 m/s时,区分轻、中度吻合口狭窄的敏感性、特异性最高.左侧心室舒张末期容积、收缩末期容积、射血分数及左室壁厚度与PWV无明显相关性.结论 CoA术后患儿PWV升高,中度吻合口狭窄患儿存在较显著主动脉重构.

Evaluation of aorta's compliance after repair of coarctation of aorta using pulse wave velocity of MRI

Objective To evaluate aorta's compliance after repair of coarctation of the aorta (CoA)using the pulse wave velocity (PWV)of MRI.Methods A retrospective analysis of cardiac MR images in 22 patients after repair of CoA was performed.PWV was measured and calculated with phase contrast MRI,and echocardiography was performed to measure both ventricular function and myocardial thickness during the same period.Age and sex-matched 22 normal subjects were served as a control group and their aortic PWVs were measured.Results The averaged PWV in study group was significantly higher than that in control group (4 .42 ± 3 .02 )m/s vs (2 .73 ± 0 .76 )m/s,P =0.02].In study group,the PWV value of children with moderate anastomotic stenosis was the highest. ROC curve analysis showed the highest sensitivity and specificity could be achieved to distinguish the mild or moderate anastomotic stenosis when the threshold for PWV was 3.37 m/s.No significant correlations were found between left ventricular end-diastolic volume,left ventricular end-systolic volume,ejection fraction,left ventricular thickness and PWV.Conclusion PWV is increased in children after repair of CoA.Significant aortic remodelling can be observed in patients with moderate anastomotic stenosis.