The perfect match: Aortic valve sizing to maximize hemodynamic performance and survival

Objective: We assessed the value of using a size ratio of implanted valve opening diameter to native annular diameter to determine postoperative hemodynamics and survival after surgical aortic valve replacement. Methods: In total, 1519 patients from 3 trials had a preoperative computed tomography scan. A size ratio was created using the implanted valve's Ebels' prosthetic valve−derived effective diameter (ED) and the patient's computed tomography perimeter−derived native annular diameter (CTD). Restricted cubic spline curves showed the association between size ratio and hemodynamic performance. Patients were divided into 3 ratio groups: <80%, 80% to 90%, and >90%. Hemodynamic performance was evaluated yearly for 5 years. Multivariable proportional hazard regression examined the association between size ratio and 5-year survival. Results: Mean valve gradient, peak velocity, effective orifice area (EOA), indexed EOA, dimensionless velocity index, and prosthesis-patient mismatch were significantly better advancing from the 80% to the 90% groups (P < .001). The >90% group had a single-digit mean valve gradient, peak velocity ≤2.0 m/s, EOA ≥2.0 cm2, indexed EOA ≥1.0 cm2/m2, dimensionless velocity index ≥0.5, and no prosthesis-patient mismatch ≥85% at 1 and 5 years. Size ratio was an independent predictor of mortality with survival benefit through 5 years (80%-90% vs <80%, hazard ratio, 0.752; 95% confidence interval, 0.611-0.927, P = .008; >90% vs <80%, hazard ratio, 0.712; 95% confidence interval, 0.506-1.001, P = .05). Conclusions: An ED/CTD size ratio >90% is associated with optimal postoperative hemodynamic performance and improved 5-year survival. Preoperative ED/CTD ratio provides the ideal implanted valve size and helps determine if annular enlargement is necessary.