Paediatric Cardiology Unit, Children's Hospital, Toulouse University Hospital, Toulouse, France.
Arch Cardiovasc Dis. 2013 May;106(5):295-302. doi: 10.1016/j.acvd.2012.11.005. Epub 2013 Mar 11.
Congenital bicuspid aortic valve (BAV) is the most common congenital heart defect and may be responsible for aortic stenosis early in life. However, its pathogenesis remains unclear. A relationship between the severity of aortic stenosis and valvular surfaces has not been reported in the paediatric population.
To assess the feasibility of three-dimensional transthoracic echocardiographic planimetry in congenital BAV in children and to evaluate the influence of valvular asymmetry and aortic valve area (AVA) on stenosis severity.
Seventy consecutive children with BAV were included in this prospective single-centre study. Using the multiplanar review mode, surfaces were measured by planimetry (in systole for AVA and diastole for cusp surfaces). The degree of stenosis was assessed by instantaneous aortic Doppler. Results are expressed as medians and first and third quartiles.
Median age was 5.6 years (2.2-11.5). Feasibility was 97%. Intra- and interobserver concordances were excellent for the measurement of cusp surfaces and AVA. Among the 70 children, 25 had aortic stenosis. The small/large cusp ratio was strongly associated with aortic stenosis (P<0.001). The area under the receiver operating characteristic curve was 0.89 (95% confidence interval 0.82-0.97). The best cut-off value for differentiating stenotic from non-stenotic valve was 0.75, with 84% sensitivity and 83% specificity. When indexed for body surface area, AVA was significantly smaller (P=0.031) in case of stenotic BAV (1.51cm(2) [0.99-2.28]) compared with non-stenotic BAV (1.99cm(2) [1.57-2.52]).
Three-dimensional echocardiographic planimetry is a feasible and reproducible method for assessing aortic surfaces in congenital BAV. Aortic stenosis seems to strongly depend on the asymmetry of the valve.
先天性二叶式主动脉瓣（BAV）是最常见的先天性心脏缺陷，可能导致生命早期的主动脉瓣狭窄。然而，其发病机制尚不清楚。在儿科人群中，主动脉瓣狭窄的严重程度与瓣叶表面之间的关系尚未有报道。
评估三维经胸超声心动图在儿童先天性 BAV 中的可行性，并评估瓣叶不对称和主动脉瓣口面积（AVA）对狭窄严重程度的影响。
本前瞻性单中心研究纳入了 70 例连续的 BAV 患儿。使用多平面回顾模式，通过平面测量法（收缩期测量 AVA，舒张期测量瓣叶表面）测量瓣叶表面。狭窄程度通过即时主动脉多普勒评估。结果表示为中位数及第一四分位数和第三四分位数。
中位年龄为 5.6 岁（2.2-11.5）。可行性为 97%。测量瓣叶表面和 AVA 的观察者内和观察者间一致性均极好。70 例患儿中，25 例存在主动脉瓣狭窄。小/大瓣叶比值与主动脉瓣狭窄密切相关（P<0.001）。受试者工作特征曲线下面积为 0.89（95%置信区间 0.82-0.97）。区分狭窄和非狭窄瓣膜的最佳截断值为 0.75，其敏感性为 84%，特异性为 83%。当按体表面积校正时，狭窄性 BAV 的 AVA 明显较小（P=0.031）（1.51cm2[0.99-2.28]），而非狭窄性 BAV 的 AVA 较大（1.99cm2[1.57-2.52]）。
三维超声心动图平面测量法是评估先天性 BAV 主动脉瓣叶的一种可行且可重复的方法。主动脉瓣狭窄似乎强烈依赖于瓣叶的不对称性。
