Echocardiographic Evaluation Of Elasticity Of Widen Ascending Aorta And Abdominal Aorta In Patients With Bicuspid Aortic Valve

Objective: Bicuspid aortic valve(BAV)is the most common clinical congenital heart disease,which often associated with aortic valve dysfunction and aortic disease.Many studies have found that the middle layer of the aorta in BAV patients was degraded,including ruptured elastic fibers,local smooth muscle cell apoptosis,and increased proteoglycans even if do not have significant valve dysfunction,which also affected the abdominal aorta.The hemodynamics in the ascending aorta of BAV are different between different subtypes,which may be the reason for the expansion of different parts of their ascending aorta.The purpose of this study was to evaluate the elasticity of the widened ascending aorta and abdominal aorta in patients with different types of BAV using type M and two-dimensional speckle tracking.Methods: 39 patients with BAV diagnosis of normal valve function whose ascending aorta greater than 19 mm / m2 in males and greater than 22 mm / m2 in females were enrolled.According to the Sievers’ classification,they were divided into without a raphe(type BAV 0)and one raphe(left-right fusion,type BAV L-R;right-non-coronary fusion,type BAV R-N).In addition,20 sex and age-matched people were selected as the control group.The elasticity of the ascending aorta and abdominal aorta in each group was measured and analyzed.1.Conventional echocardiography parameters: aortic valve peak velocity(PFV),aortic valve peak pressure gradient(PPG),aortic valve mean pressure gradient(MPG),aortic valve area(AVA)was calculated,and left ventricular ejection fraction(LVEF).2.Aortic elasticity parameter:(1)Type M parameters: ascending aortic systolic diameter(AoS),ascending aortic diastolic diameter(AoD),and aortic strain(Aortic strain),aortic stiffness index(AoSI),and aortic distensibility(AoDIS).(2)Longitudinal strain parameters: longitudinal strain of the anterior and posterior wall of ascending aorta and abdominal aorta,and also average longitudinal strain.Results: 1.Comparison between BAV group and control group(1)Type M parameters: aortic strain and AoDIS decreased(P <0.05),AoSI increased(P <0.05).(2)Longitudinal strain parameters: the longitudinal strain of the anterior ascending aorta and the longitudinal strain of the posterior ascending aorta are reduced(P <0.001);the longitudinal strain of the anterior wall of the abdominal aorta and the longitudinal strain of the posterior wall decreased(P <0.05).2.BAV subgroup analysis(1)Type M parameters(1)AoS,AoD,and AoD correction: there are no differences between Type 0,L-R,and R-N(P>0.05).(2)Aortic strain: there is no difference between type 0 and type L-R,and there is no difference between type R-N and type L-R.Type 0 increases compared with type R-N(P <0.01).(3)AoSI: type 0 is lower than type L-R(P <0.05),there is no difference between type R-N and type L-R,and type 0 was lower than type R-N(P <0.05).(4)AoDIS: there is no difference between type 0 and type L-R,and there is no difference between type R-N and type L-R.Type 0 increases compared with type R-N(P <0.01).(2)Longitudinal strain parameters(1)Longitudinal strain of the anterior wall of the ascending aorta: type 0 increased compared with type L-R(P <0.05),and type 0 increased compared with type R-N(P<0.05),there is no difference between type L-R and type R-N.(2)Longitudinal strain of the posterior wall of the ascending aorta: type 0 is reduced compared with type L-R(P <0.05),type 0 increased compared with type R-N(P<0.05),and the type R-N is lower than type L-R(P <0.01).(3)Average longitudinal strain of the ascending aorta: there is no difference between type 0 and type L-R,type 0 is increased compared with type R-N(P <0.01),type L-R increased compared with type R-N(P <0.01).(4)The anterior and posterior wall and also average longitudinal strain of abdominal aorta: there is no difference between type 0,type L-R and type R-N.3.Correlation analysisThe average longitudinal strain of the ascending aorta is negatively related to the ascending aortic systolic diameter and the diastolic diameter,negatively related to the diastole diameter corrected by body surface area,and negatively related to the systolic and diastolic blood pressure.conclusion: 1.The elasticity of widen ascending aorta in BAV patients diagnosis of normal valve function is impaired,although there is no difference in diameter of the ascending aorta between different subtypes,the degree of elasticity of the front and back walls is different,type R-N ascending aorta has the most impaired elasticity.2.The elasticity of abdominal aorta in BAV patients diagnosis of normal valve function is impaired,but there is no difference in abdominal aortic elasticity between different subtypes.3.The average longitudinal strain of the anterior and posterior wall of the ascending aorta is negatively related to the diameter of the ascending aorta and blood pressure,so it is particularly important to monitor the diameter of the aorta and control blood pressure.