Valve Replacement in Narrow Aortic Roots: Serial Hemodynamics and Long-Term Clinical Outcome

Abstract

No long-term data are available that correlate clinical outcome with serial hemodynamic studies for small-diameter (17-mm or 19-mm) aortic prostheses implanted without enlargement of the annulus. After insertion of these valves without annuloplasty, 52 patients underwent resting catheterization and were followed up at the Surgery Clinic of the National Heart, Lung, and Blood Institute for 295 patient-years (mean, 5.7 years per patient). At similar flow rates, peak systolic gradients across 17-mm Björk-Shiley aortic prostheses (N = 6) tended to exceed those of the 19-mm Björk-Shiley model (N = 38); these gradients averaged 30 ± 6 mm Hg (mean ± standard error of the mean) and 20 ± 2 mm Hg, respectively ( p = .053). Those patients with 19-mm Hancock (N = 4) and St. Jude Medical valves (N = 4) were studied, and the lowest prosthetic gradients were found with the St. Jude Medical prosthesis (mean, 3 ± 2 mm Hg). Aortic gradient was independent of flow for 17-mm but not for 19-mm Björk-Shiley valves. There was no difference in calculated effective orifice area with respect to valve size. Effective orifice area and prosthetic gradients were stable during intervals of 2 to 12 years in 10 patients who underwent additional catheterizations. No association was found between prosthetic gradients, flows, or calculated orifice areas and early or late functional class. Actuarial survival was 86 ± 5% at 5 years, 83 ± 5% at 8 years, 71 ± 9% at 10 years, and 60 ± 12% at 12 years of complete follow-up. It is concluded that small aortic prostheses provide acceptable palliation for long periods and that resting hemodynamic studies have a limited predictive value for long-term prognosis.