Role of CTA-derived imaging parameters in bicuspid-aortic valve associated aortopathy

Ascending aortic diameter is routinely used for clinical decision-making in bicuspid aortic valve (BAV) patients but is an imperfect predictor of aortic growth and outcomes. This study investigates the potential of additional imaging parameters in predicting ascending aortic diameter growth in BAV patients.

Baseline imaging characteristics from cardiothoracic CT angiograms (CTA) performed from Jan 2004 to Apr 2020 were reviewed. The median imaging follow-up duration was 5.4 years (IQR 4.7-6.0 years). Parameters included BAV morphology, aortic valve calcium score (AVCS), aortic annulus and ascending aorta angles, aortic and greater curvature length, and maximum root, ascending, and descending diameters. Additional data on demographics, medical, and family history were obtained. Statistical analysis included Pearson's correlation, univariate and multivariate logistic regression.

148 BAV patients (52.7 ± 11.7 years, 119 males) were evaluated. Baseline aortic and greater curvature length, maximum root and ascending aortic diameters, and ascending:descending (A:D) ratio positively correlated with ascending aortic diameter growth rate (p = 0.005, 0.019, 0.018, 0.002, 0.021). Longitudinal growth analyses were carried out in a subset of patients without interval surgery (n = 121). Ascending aortic angle correlated negatively with growth rate (p = 0.005). Using a threshold growth rate of ≥0.7 mm/year, A:D ratio, aortic, and greater curvature length increased the odds of growth (OR = 24.114, 1.181, 1.039). Multivariate analysis revealed that ascending aortic angle predicted aortic growth (OR = 0.947, p = 0.031), and AVCS predicted subsequent surgery (OR = 1.001, p = 0.041).

Aortic length, greater curvature length, and A:D ratio can predict ascending aortic diameter growth in BAV patients.