Clinical and haemodynamic evaluation of 19mm Bjork-Shiley aortic valve prosthesis

Between November, 1973, and March, 1980, 43 patients underwent isolated aortic valve replacement with 19 mm Björk-Shiley prostheses at the Johns Hopkins Hospital. There were 4 male and 39 female patients ranging from 12 to 75 years old (mean, 54.5 years). Average weight was 62 ± 2 kg and average body surface area, 1.64 ± 0.3 m². Five patients died within thirty days of operation; however, since 1975, hospital mortality has been 5.9%. The 38 survivors have been followed up for as long as 85 months (mean, 40 months). There were 4 late deaths, and actuarial survival in patients discharged from the hospital was 81% at five years. All long-term survivors were in New York Heart Association Functional Class I (29 patients) or Class II (5 patients). Preoperative and postoperative echocardiograms in 17 patients demonstrated significant decreases in mean left ventricular wall thickness (12.9 ± 1.8 mm vs 10.3 ± 1.4 mm; p < 0.001) and in left ventricular mass (262 ± 95 gm vs 188 ± 50 gm; p < 0.02).

Postoperative cardiac catheterization data were obtained from an additional 24 patients undergoing aortic valve replacement with the 19 mm Björk-Shiley prosthesis at the National Heart Institute. Average peak systolic gradient at rest was 16 mm Hg (range, 0 to 45 mm Hg) and was found to be directly related to body surface area (r = 0.60, p < 0.002). Average effective valve orifice area was 1.06 cm² (range, 0.63 to 2.02 cm²).

For patients with small aortic roots, aortic valve replacement with the 19 mm Björk-Shiley valve is a satisfactory and, perhaps, preferable alternative to aortic annuloplasty to accommodate larger sized prostheses.