Preliminary experience with the St. Jude Medical Regent mechanical heart valve in the aortic position: early in vivo hemodynamic results

Background. The St. Jude Medical Regent is a new generation mechanical aortic valve. Methods. Between March 2000 and July 2001, this valve was implanted in the aortic position in 40 patients (21 men; mean age 59.1 ± 9.0 years). Preoperatively, 24 patients (60%) were in New York Heart Association functional class III or IV. Eighteen patients (45%) underwent associated procedures. Mean valve size was 21.4 ± 2.4 mm. The mean duration of follow-up was 8.5 ± 4.5 months (range, 1 to 16 months). Results. There were no operative deaths. Early complications included one reoperation for bleeding and one transient low output syndrome. Valve replacement was followed by a significant reduction in mean and peak transaortic gradients over time (p< 0.001) and analysis of variance failed to demonstrate statistical differences between valve size over time (p = not significant). A significant reduction in left ventricular hypertrophy occurred over time (p = 0.01) in all valve sizes (p = not significant between groups): baseline left ventricular mass index was 194 g/cm2; it reduced by 22 g/cm2 (p = 0.006) at discharge. Left ventricular mass index decreased from 172 ± 55 g/cm2 to 156 ± 44 g/cm2 (p = 0.03) from discharge to 2 months. Further reductions were not significant. Relative wall thickness decreased from 0.57 ± 0.13 preoperatively to 0.42 ± 0.06 at discharge (p = 0.001), and again at 2 months (−0.2; p = not significant), and at 1 year (−0.02; p = not significant). Conclusions. The early experience with the St. Jude Medical Regent valve has been satisfactory.