Aortic elasticity and the influence of valve morphology in children with bicuspid aortic valve

Abstract

Aim: We investigated dimensions and elasticity of whole aorta in patients with bicuspid aortic valve and influence of valve phenotype. Method: The study group included 44 patients and 42 controls. Patients were divided into groups according to the type of valve opening as horizontal - fusion between right and left coronary cusps - and vertical - fusion between right-non-coronary cusps; according to age they were divided into younger (5-10 years) and older patients (11-16 years). Our study did not include valve phenotype with fusion between left and non-coronary cusps. Systolic-diastolic diameters of aortic annulus, sinus valsalva, sinutubular junction, arcus, and ascending-descending and abdominal aorta were measured and z-scores were obtained. Aortic strain, distensibility, and stiffness index were calculated. Flow-mediated dilatation of brachial artery was studied. Results: z-Scores at annulus, sinus valsalva, sinutubular junction, and ascending aorta were higher in study patients (p = 0.001, p = 0.0001, p = 0.0001, p = 0.0001, respectively). z-Scores of sinus valsalva and sinotubular junction were higher in the horizontal group than in the vertical group (p = 0.006, p = 0.023, respectively). z-Score was over +2 in 51% of patients with horizontal morphology and 33% of patients with vertical morphology (p = 0.0001). Ascending aorta was more distensible and less stiff in the study group (11.3 +/- 5.63 versus 7.91 +/- 4.5, p = 0.002; 4.76 +/- 3.60 versus 6.19 +/- 3.44 cm(2).dyn(-1).10(-6) p = 0.033, respectively). Stiffness index of ascending, arcus, and abdominal aorta were higher in the horizontal group (p = 0.004, p = 0.038, p = 0.006, respectively). Ascending aorta was more distensible and less stiff in the younger group (p = 0.007, p = 0.027, respectively) but did not differ in the older group compared with the control group. Conclusion: Aortic dimensions arc enlarged in patients with bicuspid aortic valve starting from childhood, suggesting the presence of generalised aortopathy. Aortic elasticity is increased at young age and decreased with age.