Invasive Complications and Infection-Related Reconstruction in Bicuspid Versus Tricuspid Native Aortic Valve Endocarditis: A 12-Year Surgical Cohort Study

Background: Detailed operative evidence comparing invasive anatomy and reconstruction between bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) cases of native-valve infective endocarditis is limited. We examined the association of BAV morphology with non-leaflet invasive complications and infection-related reconstruction. Methods: We retrospectively studied 317 adults who underwent surgery for native aortic valve infective endocarditis from 2013 through 2025 (113 BAV; 204 TAV). The primary outcome was any non-leaflet invasive complication; infection-related reconstruction was a secondary operative outcome reflecting operative management of invasive anatomy. Modified Poisson regression estimated adjusted prevalence ratios (aPRs), corresponding 95% confidence intervals (CIs), and marginally standardized absolute differences. Site-specific and invasive-subgroup analyses were exploratory. Results: Patients with BAV were younger, more frequently male, and had a lower comorbidity burden. Non-leaflet invasive complications occurred in 44.2% of patients with BAV and 18.6% with TAV (aPR, 2.08; 95% CI, 1.41–3.06; adjusted absolute difference, 21.1 percentage points; 95% CI, 9.6–32.6). Abscess involving non-leaflet structures was more frequent in BAV than in TAV (43.4% vs. 16.7%; p < 0.001). In the full cohort, aortic annular and left ventricular outflow tract involvement were more frequent in BAV. Infection-related reconstruction was performed in 31.9% of patients with BAV and 15.2% of those with TAV. Within the invasive subgroup, reconstruction was performed in 72.0% and 81.6% of BAV and TAV cases, respectively (unadjusted PR, 0.88; 95% CI, 0.70–1.11). Early mortality was low in both groups, and the adjusted analysis did not identify a clear difference in long-term mortality. Conclusions: Bicuspid morphology was associated with a higher prevalence of non-leaflet invasive complications, predominantly abscess, and a higher overall frequency of infection-related reconstruction.