Abstract：
Bicuspid aortic valve (BAV) is associated with progressive aortic dilation. Although the etiology is complex, altered flow dynamics is thought to play an important role. Blood speckle tracking (BST) allows for visualization and quantification of complex flow, which could be useful in identifying patients at risk of root dilation and could aid in surgical planning. The aims of this study were to assess and quantify flow in the aortic root and left ventricle using BST in children with bicuspid aortic valves.
A total of 38 children <10 y of age were included (24 controls, 14 with BAV). Flow dynamics were examined using BST in the aortic root and left ventricle. Children with BAV had altered systolic flow patterns in the aortic root and higher aortic root average vorticity (25.9 [23.4-29.2] Hz vs. 17.8 [9.0-26.2] Hz, p < 0.05), vector complexity (0.17 [0.14-0.31] vs. 0.05 [0.02-0.13], p < 0.01) and rate of energy loss (7.9 [4.9-12.1] mW/m vs. 2.7 [1.2-7.4] mW/m, p = 0.01). Left ventricular average diastolic vorticity (20.9 ± 5.8 Hz vs. 11.4 ± 5.2 Hz, p < 0.01), kinetic energy (0.11 ± 0.05 J/m vs. 0.04 ± 0.02 J/m, p < 0.01), vector complexity (0.38 ± 0.1 vs. 0.23 ± 0.1, p < 0.01) and rate of energy loss (11.1 ± 4.8 mW/m vs. 2.7 ± 1.9 mW/m, p < 0.01) were higher in children with BAV.
Children with BAV exhibit altered flow dynamics in the aortic root and left ventricle in the absence of significant aortic root dilation. This may represent a substrate and potential predictor for future dilation and diastolic dysfunction.
A total of 38 children <10 y of age were included (24 controls, 14 with BAV). Flow dynamics were examined using BST in the aortic root and left ventricle. Children with BAV had altered systolic flow patterns in the aortic root and higher aortic root average vorticity (25.9 [23.4-29.2] Hz vs. 17.8 [9.0-26.2] Hz, p < 0.05), vector complexity (0.17 [0.14-0.31] vs. 0.05 [0.02-0.13], p < 0.01) and rate of energy loss (7.9 [4.9-12.1] mW/m vs. 2.7 [1.2-7.4] mW/m, p = 0.01). Left ventricular average diastolic vorticity (20.9 ± 5.8 Hz vs. 11.4 ± 5.2 Hz, p < 0.01), kinetic energy (0.11 ± 0.05 J/m vs. 0.04 ± 0.02 J/m, p < 0.01), vector complexity (0.38 ± 0.1 vs. 0.23 ± 0.1, p < 0.01) and rate of energy loss (11.1 ± 4.8 mW/m vs. 2.7 ± 1.9 mW/m, p < 0.01) were higher in children with BAV.
Children with BAV exhibit altered flow dynamics in the aortic root and left ventricle in the absence of significant aortic root dilation. This may represent a substrate and potential predictor for future dilation and diastolic dysfunction.
摘要：
目的：二叶主动脉瓣（BAV）与进行性主动脉扩张有关。虽然病因复杂,改变的流动动力学被认为起着重要的作用。血液斑点跟踪（BST）允许复杂流动的可视化和量化，这可能有助于识别有根部扩张风险的患者，并有助于手术计划。这项研究的目的是使用BST评估和量化二叶主动脉瓣患儿的主动脉根部和左心室的流量。
结果：共纳入38名年龄<10岁的儿童（24名对照，14与BAV）。使用BST检查主动脉根部和左心室的血流动力学。BAV患儿主动脉根部收缩期血流模式改变，主动脉根部平均涡度较高（25.9[23.4-29.2]Hzvs.17.8[9.0-26.2]Hz,p<0.05)，向量复杂度(0.17[0.14-0.31]与0.05[0.02-0.13]，p<0.01）和能量损失率（7.9[4.9-12.1]mW/m与2.7[1.2-7.4]mW/m,p=0.01)。左心室平均舒张涡度（20.9±5.8Hzvs.11.4±5.2Hz,p<0.01),动能(0.11±0.05J/mvs.0.04±0.02J/m,p<0.01),向量复杂度(0.38±0.1vs.0.23±0.1，p<0.01）和能量损失率（11.1±4.8mW/mvs.2.7±1.9mW/m,p<0.01）在BAV儿童中更高。
结论：在没有明显主动脉根部扩张的情况下，BAV患儿在主动脉根部和左心室的血流动力学改变。这可能是未来扩张和舒张功能障碍的基础和潜在预测因素。
结果：共纳入38名年龄<10岁的儿童（24名对照，14与BAV）。使用BST检查主动脉根部和左心室的血流动力学。BAV患儿主动脉根部收缩期血流模式改变，主动脉根部平均涡度较高（25.9[23.4-29.2]Hzvs.17.8[9.0-26.2]Hz,p<0.05)，向量复杂度(0.17[0.14-0.31]与0.05[0.02-0.13]，p<0.01）和能量损失率（7.9[4.9-12.1]mW/m与2.7[1.2-7.4]mW/m,p=0.01)。左心室平均舒张涡度（20.9±5.8Hzvs.11.4±5.2Hz,p<0.01),动能(0.11±0.05J/mvs.0.04±0.02J/m,p<0.01),向量复杂度(0.38±0.1vs.0.23±0.1，p<0.01）和能量损失率（11.1±4.8mW/mvs.2.7±1.9mW/m,p<0.01）在BAV儿童中更高。
结论：在没有明显主动脉根部扩张的情况下，BAV患儿在主动脉根部和左心室的血流动力学改变。这可能是未来扩张和舒张功能障碍的基础和潜在预测因素。
