Application of Regent mechanical valve in patients with small aortic annulus: 3-year follow-up.

Background: Aortic valve replacement (AVR) with a small aortic annulus is always challenging for the cardiac surgeon. In this study, we sought to evaluate the midterm performance of implantation with a 17-mm or 19-mm St. Jude Medical Regent (SJM Regent) mechanical valve in retrospective consecutive cohort of patients with small aortic annulus (diameter ≤19 mm). Methods: From January 2008 to April 2011, 40 patients (31 female, mean age=47.2±5.8 years) with small aortic annulus (≤19 mm in diameter) underwent aortic valve replacement with a 17-mm or 19-mm St. Jude Medical Regent (SJM Regent) mechanical valve. Preoperative mean body surface area, New York Heart Association class, and mean aortic annulus were 1.61±0.26 m 2 , 3.2±0.4, and 18±1.4 mm respectively. Patients were divided into two groups, according to the implantation of 17 mm SJM Regent mechanical valve (group 1, n=18) or 19 mm SJM Regent valve (group 2, n=22). All patients underwent echocardiography examination preoperatively and at one year post-operation. Results: There were no early deaths in either group. Follow-up time averaged 36±17.6 months. The mean postoperative New York Heart Association class was 1.3±0.6 (p<0.001). By echocardiography, in group 1, the left ventricular ejection fraction (LVEF), left ventricular fraction shortening (LVFS), and the indexed effective orifice area (EOAI) increased from 43.7%±11.6%, 27.3%±7.6%, and 0.70±0.06 cm 2 /m 2 to 69.8±9.3%, 41.4±8.3%, and 0.92±0.10 cm 2 /m 2 respectively (P<0.05), while the left ventricular mass index (LVMI), and the aortic transvalvular pressure gradient decreased from 116.4±25.4 g/m 2 , 46.1±8.5 mmHg to 86.7±18.2 g/m 2 , 13.7±5.2 mmHg respectively. In group 2, the LVEF, LVFS and EOAI increased from 45.9%±9.7%, 30.7%±8.0%, and 0.81±0.09 cm 2 /m 2 to 77.4%±9.7%, 44.5%±9.6%, and 1.27±0.11 cm 2 /m 2 respectively, while the LVMI, and the aortic transvalvular pressure gradient decreased from 118.3±27.6 g/m 2 , 44.0±6.7 mmHg to 80.1±19.7 g/m 2 , 10.8±4.1 mmHg as well. The prevalence of PPM was documented in 2 patients in Group 1. Conclusions: Patients with small aortic annulus and body surface area, experienced satisfactory clinical improvement after aortic valve replacement with modern SJM Regent bileaflet prostheses.