Aortic Valve Replacement in Patients with Narrow Aortic Annulus : Clinical Evaluation of 19 mm St. Jude Medical Hemodynamic Plus Valve Prosthesis

Abstract

The 19 mm St. Jude Medical (SJM) Hemodynamic Plus valve prosthesis (19HP) is frequently used for aortic valve replacement patients with a small aortic annulus and small body surface area (BSA). Some patients with a 19HP have demonstrated a high aortic valve pressure gradient (AVG) across the prosthesis. This study was undertaken to assess the effectiveness of the 19HP valve and to examine if it could improve the patient's quality of life. The hemodynamic performance of the 19HP was compared to that of the standard St. Jude Medical 19A (19Std). Also, characteristics of patients who had high AVG were analyzed. Between January, 1980, and June, 1999, 66 patients underwent aortic valve replacement (AVR) with a 19HP and 20 patients with a 19Std. Long-term actuarial survival and event-free proportion were significantly higher in the 19HP group. No significant difference in the postoperative New York Heart Association classification was observed. Echocardiography showed a significant decrease in peak AVG in the 19HP group. However, 36.4% of the 19HP group still had a peak AVG above 30 mmHg at rest. All chronic hemodialysis patients in both groups showed severe AVG. Postoperative AVG showed no correlation with either the patient's BSA or the preoperative valvular lesions in the 19HP group. In conclusion, 19HP improved the prognosis of patients with a small annulus. However some patients still had a high AVG, and hemodialysis was thought to be an influential factor. An alternative procedure or enlargement of the aortic root might be required in such patients