Valve Oversizing and Geometric Factors in Structural Valve Deterioration After Pulmonary Valve Replacement

Valve oversizing has been associated with structural valve deterioration after pulmonary valve replacement, but the mechanism is unclear. We investigated whether geometric relationships between the implanted valve and the right ventricular outflow tract contribute to structural valve deterioration.

We retrospectively analyzed patients with congenital heart disease who underwent pulmonary valve replacement with a bioprosthetic valve in the native right ventricular outflow tract and had postoperative computed tomography. Four geometric parameters were quantified. Valve oversizing was assessed by indexing the true internal diameter of the valve to body surface area. Structural valve deterioration was defined as moderate or greater pulmonary regurgitation or pulmonary stenosis with peak transvalvular velocity ≥3.0 m/s. Associations were evaluated by competing risk regression.

Eighty-two patients were included, with a median follow-up of 7.2 years. Freedom from structural valve deterioration was 84% at 5 years and 65% at 10 years. Posterior angulation of the implanted valve was associated with structural valve deterioration and remained an independent predictor in multivariable analysis (adjusted hazard ratio, 83.5; 95% CI, 3.61-1930). Posterior angulation correlated with valve oversizing (r = 0.23; P = .04). A posterior angulation index cutoff value of 0.27 provided optimal discrimination for the risk.

Prosthetic valve angulation relative to the right ventricular outflow tract was associated with structural valve deterioration and was closely related to valve oversizing. Valve-outflow tract geometry, rather than valve size alone, may influence valve durability.