Morphological And Hemodynamic Analysis Of Right-sided Aortic Arch With Kommerell’s Diverticulum

Background and Objective: Though cases of the right-sided aortic arch with Kommerell’s diverticulum(RAA-KD)have been reported,the disease spectrum and morphological characteristics of RAA-KD have rarely been described.Our goal is to investigate the disease spectrum,morphology,and hemodynamics in RAA-KD.Material and Method: Part I is concerning the aortic morphology of RAA-KD.We prospectively collected data from 65 cases with RAA-KD.Areas and lengths of different aortic segments were measured.Diameters were calculated from the corresponding areas.According to the maximal diameter of KD,65 cases of RAA-KD were divided into aneurysmal group and non-aneurysmal group.Part II is the hemodynamic analysis of the aorta of RAA-KD.Based on the results from Part I,we analyze the data from 30 RAA-KD patients by applying hemodynamic technique.We use the Pearson coefficient to investigate the correlation between the time-averaged wall shear stress and the diameter of the KD.All the analysis is performed within SPSS 26.P<0.05 is considered significant.Result: Part I: Cases with RAA-KD in aneurysmal group were older(59.0±2.0yrs vs 52.0±1.5yrs,P=0.021*)and had more calcified aortic arches(70.4% vs 42.1%,P=0.024*).All diameters were positively correlated with age(P ﹤.05*)and greater in the aneurysmal group(P﹤.05*).After indexed to age,the diameter of proximal descending aorta remained greater in the aneurysmal group(P=0.001*).The lengths of ascending aorta,aortic arch,and descending aorta were positively correlated with age(P ﹤.05*),were longer in aneurysmal group(P﹤.05*),and had no difference between groups(P﹥.05)after indexed to age.The length of aortic isthmus was shorter in aneurysmal group(13.7±6.3mm vs 17.8±7.7mm,P=0.043*).The length of KD was longer in aneurysmal group(P=0.01*).The KD diameter is negatively correlated to the length of aortic isthmus and positively correlated to the KD length.PART II: In RAA-KD,the TAWSS of the KD segment do not correlate to age and the length of aortic isthmus.the TAWSS of the KD segment shows no difference between the group with calcified aortic arch and the group with non-calcified aortic arch.The TAWSS of the KD segment is negatively correlated to the diameter of KD(r= ﹣ 0.582,P=0.001*).The TAWSS is significantly lower in the aneurysmal group than in the non-aneurysmal group(0.70±0.26 Pa vs 1.17±0.81 Pa,P=0.046*).Conclusion: In patients with RAA-KD,the aorta dilated and stretched with age,and KD dilated with age.The dilation of KD was accompanied by dilation of the proximal descending aorta,elongation of KD,and shortening of the aortic isthmus.TAWSS in aorta of KD segment is lower as the KD diameter is larger.