Aortic tortuosity is related to aortic phenotype in patients with bicuspid aortic valve: A CT scan study of 83 cases

Abstract

Although the incidence of aortic dissection is higher in patients with bicuspid aortic valve (BAV) compared to tricuspid aortic valve (TAV), risk stratification remains unclear. Aortic tortuosity (AT) is emerging as a novel risk marker in patients with genetic thoracic aortic aneurysm (TAA), but has not been assessed in BAV. Our aim is to describe the relationship between AT and ascending aortic phenotype in patients with BAV. Eighty-three patients (43 ± 16 years, 19 women) with BAV but without significant aortic valve disease nor surgery were included. Aortic diameters and AT were measured on CT scans. Descending and total aortic length and tortuosity were also measured in 61 patients with abdominal images available. Sixty-two (75%) patients presented a typical BAV (LR type 1 or antero-posterior type 0). Aortic dilatation (Valsalva and/or tubular Z-score > 2) was present in 80 patients (96%) including 67 (81%) with a tubular dilatation. The aortic phenotype, the maximal aortic diameters and aortic tortuosity index were similar in typical and atypical BAV. Total aortic tortuosity index was correlated with tubular Z-score ( r = 0.31; P = 0,014) but not with Valsalva Z-score ( P = 0,55). In patients with tubular dilatation, total aortic tortuosity index was higher than in patients without tubular dilatation (2.01 vs 1.85; P = 0,015) ( Fig. 1 ). Total aortic tortuosity is associated with tubular dilatation but not with Valsalva dilatation in BAV patients suggesting that tubular phenotype may be at higher risk of complication in BAV. Further studies evaluating the association between aortic tortuosity and clinical outcomes in BAV are needed.