Ascending aortic wall degeneration in patients with bicuspid versus tricuspid aortic valve

Abstract

Background The magnitude of ascending aortic degeneration in patients with bicuspid aortic valves (BAV) is controversial. Methods The aim of this study was to investigate ascending aortic wall degeneration in patients with BAV as compared with tricuspid aortic valves (TAV). The ascending aortic wall of 67 consecutive patients was processed for histology and immunohistochemistry. The extent of surgery and wall degeneration were investigated. Unadjusted survival was evaluated by Kaplan–Meier analysis. Median follow-up for patients with BAV and TAV was 3.8 years (interquartile range [IQR] 3.5–4.1) and 3.7 years (IQR 3.4–3.9), respectively. Results There were 33 patients with BAV and 34 with TAV. Mid-ascending aorta diameter was 54 mm (IQR 50–60). Replacement of the aortic valve, together with an ascending aortic prosthesis, was more frequent in BAV vs TAV patients (24% vs. 3%, P = 0.013). However, medial fibrosis, elastic fiber thinning, incremental medial degeneration and smooth muscle cell nuclei loss were less prominent in BAV vs TAV patients (0.1 ± 0.4 vs. 0.8 ± 1.4, P = 0.016; 0.6 ± 1.4 vs. 1.6 ± 2.0, P = 0.027; 1.7 ± 0.7 vs. 2.2 ± 0.8, P = 0.045 and 2.3 ± 1.5 vs. 3.2 ± 1.3, P = 0.026, respectively). Conclusions Since degeneration of the ascending aortic wall was seldom prominent, histopathology alone may not support the need for surgery of the dilated ascending aorta in BAV patients as compared with TAV patients.

SPP1/osteopontin: a driver of fibrosis and inflammation in degenerative ascending aortic aneurysm?

“…The intima-media layer of each aorta was separated from the adventitia and mRNA was extracted from the former using an RNeasy kit (Qiagen, Hilden, Germany), according to the manufacturer’s instructions. Global gene expression was then measured in 23 participants with TAV-ND, 21 with TAV-D, 31 with BAV-ND, and 44 with BAV-D using an Affymetrix GeneChip® Human Exon 1.0 ST array and the associated protocols, as previously described [ 7 ].…”

“…In BAV-associated AscAA, EndMT seems to manifest in the aortic intima-media, leaving the aortic wall structurally well-preserved. In TAV patients, on the other hand, EndMT-related changes are signified by medial degeneration [ 7 ], elastin fragmentation, excessive matrix component production, smooth muscle cell depletion, and, notably, inflammation [ 4 , 8 ]. These are key features of a fibrotic type of EndMT, which interestingly also have been identified in abdominal aortic aneurysms (AAAs) [ 9 , 10 ].…”