Assessment of the St. Jude Medical Regent Prosthetic Valve by Continuous-Wave Doppler and Dobutamine Stress Echocardiography

Abstract

The St. Jude Medical (SJM) Regent prosthetic valve (St. Paul, MN), a recently developed mechanical valve, is an improvement on the conventional SJM valve, having a wider valve area than the SJM HP valve. We evaluated this mechanical valve by Doppler echocardiography and dobutamine stress echocardiography (DSE). The functions of the SJM Regent valve were evaluated by continuous-wave Doppler echocardiography and DES in 58 cases of aortic valve replacement during a stable postoperative period. The peak pressure gradient of the replaced valves sized 17, 19, 21, and 23 mm was 27.5 +/- 11.1, 20.0 +/- 9.8, 15.6 +/- 5.7, and 14.3 +/- 9.1, mm Hg respectively, and the effective orifice area index was 0.97 +/- 0.32, 1.01 +/- 0.29, 1.09 +/- 0.30, and 1.41 +/- 0.54 cm(2)/m(2), respectively, with prosthesis-patient mismatch (PPM) found in 1, 3, 2, and 0 cases for the 17-, 19-, 21- and 23-mm valves, respectively, with a total incidence of 10.3%. In 20 cases, the peak pressure gradient and the effective orifice area index were significantly increased during DSE compared with those at rest. Although the PPM incidence was 6.6%, it was deemed from the data of DSE and clinical symptoms that there were no clinical issues for such cases of PPM in the early and intermediate phases after operation. Particularly, the effectiveness of the 17- and 19-mm valves in patients with a small aortic annulus was demonstrated, confirming the satisfactory functions of the SJM Regent prosthetic valve.