Clinical Outcomes in Patients With Bicuspid Aortic Valves and Ascending Aorta ≥50 mm Under Surveillance

Background: Clinical outcomes of bicuspid aortic valve (BAV) patients with ascending aortic diameters ≥50 mm who are under surveillance are poorly defined. Objectives: The purpose of this study was to assess clinical outcomes in BAV patients with ascending aorta ≥50 mm. Methods: Multicenter retrospective cohort study of BAV adults with ascending aorta diameters ≥50 mm by transthoracic echocardiography (TTE). Patients were categorized into 50 to 54 mm and ≥55 mm groups. Clinical outcomes were aortic dissection (AoD), aorta surgery, surgical mortality, and all-cause death. Results: Of 875 consecutive BAV patients (age 60 ± 13 years, 86% men, aortic diameter 51 mm [interquartile range (IQR): 50-53 mm]), 328 (37%) underwent early surgery ≤3 months from index TTE. Of the remaining 547 patients under surveillance, 496 had diameters 50 to 54 mm and 51 had diameters ≥55 mm and were collectively followed for 7.51 (IQR: 3.98-12.20) years. Of 496 patients with diameters 50 to 54 mm under surveillance, 266 (54%) underwent surgery 2.0 (IQR: 0.77-4.16) years from index TTE. AoD occurred in 9/496 (1.8%) patients for an incidence of 0.4 cases per 100 person-years, surgical mortality was 5/266 (1.9%); and ≥moderate aortic stenosis (but not aorta size) was associated with all-cause death, hazard ratio: 2.05 (95% CI: 1.32-3.20), P = 0.001. Conversely, in 547 total patients under surveillance (including 50-54 mm and ≥55 mm), both aorta size and ≥moderate aortic stenosis were associated with all-cause death (both P ≤ 0.027). AoD rate in patients ≥55 mm under surveillance was 5.9%. Conclusions: In BAV patients with ascending aorta 50 to 54 mm under surveillance, AoD incidence is low and the overall rates of AoD and surgical mortality are similar, suggesting clinical equivalence between surgical and surveillance strategies. Conversely, patients with aortas ≥55 mm should undergo surgery. Aortic stenosis is associated with all-cause death in these patients.