Abstract 102: Granular Media Calcinosis in the Aortic Wall of Patients With Bicuspid and Tricuspid Aortic Valves

Abstract

Background: Bicuspid aortic valve is the most frequent congenital cardiac abnormality and associated with proximal aortic disease (i.e. aneurysm, dissection or rupture). Granular media calcinosis(GMC)--suggested to increase stiffness and play a pathogenetic role in dissecting aneurysm--has not yet been quantified in BAV. Methods: Specimen of the proximal aortic wall from 76 patients--32 with tricuspid (TAV) and 44 with bicuspid aortic valve (BAV)--were obtained during surgery to quantify media thickness and GMC by von Kossa staining (panel C), comparing the convexity (Cvx) and concavity (Ccv) in BAV vs. TAV. Results: Interlamellar GMC affected the most central layers of the media and those adjacent to the outer adventitia with a doubling within both--the Cvx and Ccv--of pts with BAV compared to patients with TAV (13.3±9.6 vs. 6.6±7.4 and 12.8±10.8 vs. 6.4±7.1; p<0.05, panel A) was seen, but neither a difference in calcification between the Ccx and the Ccv side within the BAV nor the TAV group. No association between age and calcification grade , neither in the Cvx nor the Ccv (r=0.132, p=0.218 and 0.103, p=0.341) was seen. There was a significant difference in the total media thickness between BAV and TAV at the Cvx (867±162μm vs . 993±158μm; p<0.05) and the Ccv (1005 ± 236 vs 1223 ± 217μm; p<0.05, panel B). Independent of aortic valve morphology, the Cvx was thinner than the Ccv side (TAV: 993 ± 158 vs.1223 ± 217μm; p<0.001; BAV: 869 ± 162 vs.1005 ± 236μm; p<0.05, panel B). Conclusion: BAVs had significantly thinner media and twice as much GMC than their tricuspid peers possibly associated with the loosening of the bond between the elastic lamellae causing a decrease in elasticity possibly explaining a higher risk for dissection and rupture.