The Study About The Deformation And The Hemodynamics Of The Bicuspid Aortic Valve And The Ascending Aorta By Using The CTA And 4D Flow MRI

Objective:Retrospectively evaluate the type of aortic valves fusion,calcification of aortic valves and width of ascending aorta in the patients with bicuspid aortic valve(BAV)by using cardiac CTA images.Correlations between the type of aortic valves fusion and calcification of aortic valves,width of ascending aorta were discussed.Methods:A total of 165 BAV patients from August 2015 through December 2016 in this single center were retrospectively analyzed,including 113 males.Average age of the patients was 53.7±10.4 years.According to the CTA data,patients were classified into five groups,valvular fusion of right and left coronary cusps(RL type),valvular fusion of right and non-coronary cusps(RN type),valvular fusion of left and non-coronary cusps(LN type),anterior-posterior valves(AP type)and lateral valves(LA type).Diameter of aortic annulus,sinuses of Valsalva,sinotubular junction and proximal ascending aorta was measured.Degree of aortic valvular calcification was assessed.Results :30.3%(50/165)patients were RL type,13.9%(23/165)patients were RN type,6.1%(10/160)patients were LN type,7.3%(12/165)patients were AP type and42.4%(70/165)patients were LA type.Diameter of aortic annulus is widest in RL group(P=0.046).Diameter of sinuses of Valsalva is widest in RN group(P=0.263).Diameter of sinotubular junction(P=0.621)and proximal ascending aorta(P=0.467)is widest in AP group.Significant different was shown in diameter of aortic annulus between RL type and LA group(P=0.001),LN group(P=0.007).Diameter of sinusesof Valsalva in RL group was significant wider than LN group(P=0.045).The degree of valvular calcification is highest in LN group(P=0.162).Significant different was shown in valvular calcification between LN and RN groups(P=0.048),between LA and RN groups(P=0.038).Conclusions:BAV with LA type was most commen in this study with LN type rare.The diameter of the aortic root is the widest in RL type patients.The degree of valvular calcification is the lowest in RN type patients with higher in LN and LA type patients.Objective Toevaluate the hemodynamic relationship between bicuspid aortic valve malformation and the deformation of ascending aorta by using 4D Flow MRI techniques.Methods 12 cases of BAV confirmed by clinic and ultrasound were prospectively enrolled.10 healthy volunteers were enrolled as control group.The MRI sequences included Cine MRI sequence,CE MRA and 4D flow MRI sequences.The peak flow,reverse flow,regurgitation fraction and the blood flow pattern of the aortic different level was measured by using CAAS MR 4D Flow post-processing software.Combined with CE MRA data,the relationship between BAV and expansion of ascending aorta was discussed.Compare(1)discrepancy of hemodynamic parameters in the same plan between the two groups;(2)discrepancy of hemodynamic parameters of one subject in different aortic plans.Results Peak flow,reverse flow and regurgitation fraction of ascending aorta in BAV group was higher than control group(p<0.05).No significant difference was found in peak flow,reverse flow and regurgitation fraction at aortic arch and descending aorta between the two groups.Significant difference generated in peak flow,reverse flow and regurgitation fraction among different aortic plans in BAV group.Peak flow,reverse flow and regurgitation fraction were decreased from ascending aorta to abdominal aorta.Blood flow pattern of BAV patients with right hand spiral vortex and complex vortex easily caused ascending aorta expansion.Conclusions The hemodynamic change is the main cause of the ascending aorta expansion in BAV patients.4D Flow MRI technique can provide information for clinical prevention and treatment of BAV patients by evaluating the hemodynamic changes.