Reduction of left ventricular hypertrophy with St. Jude Medical 19 mm valve prosthesis.

Abstract

To determine the permissible range of the St. Jude Medical 19 mm valve (SJM19) as an aortic prosthesis, transvalvular maximal pressure gradient (maxPG) and postoperative reduction of left ventricular (LV) hypertrophy were examined in 21 patients (body surface area [BSA] 1.28-1.56 m2, mean 1.42 m2). Doppler echocardiographically measured maxPG at rest was 31 +/- 16 mmHg, which showed no significant difference from the differences in patients' diseases (aortic regurgitation = AR or stenosis = AS), or BSA. The maxPG, also measured during dobutamine administration when they were less than 40 mmHg at rest, increased significantly from 21 +/- 11 mmHg to 32.1 +/- 15 mmHg, having no differences from the differences in diseases or BSA. Reduction of LV hypertrophy was achieved postoperatively (mean postoperative period of ten months), with the reduction rates of 26 +/- 19% in LV mass and 21 +/- 15% in LV cross-sectional area. No significant differences were found between the reduction rates and the differences in the patients' diseases or BSA. These results indicate that, following the implantation of SJM19, LV hypertrophy was reduced in patients with AR as well as with AS, when their BSA values were less than 1.6 m2. However, limited use is recommended because the increase in pressure gradient during exercise cannot be ignored.