Surgical outcome of stentless aortic valve replacement for calcified aortic stenosis

We have conducted aortic valve replacement (AVR) using a stentless bioprosthesis (Medtronic Freestyle valve) on 10 patients with calcified aortic stenosis since March 2004. There were 64-84 years of age and 75 ± 5.5 years old on average, and included 4 males. Implantation was conducted by a modified subcoronary method in all the patients. The preoperative New York Heart Association class was class II in 80% of the patients. The preoperative left ventricular mass and the left ventricular mass index (LVMI) were 193.1-524.1 g and 144.1-299.5 g/m2 and, on average 328.4 ± 104.7 g and 217.3 ± 55.7 g/m2, respectively. The annulus dimension was 18-24 mm and, on average, 20.3 ± 1.7 mm. The size of implanted valve was 19-25 mm and, on average, 21 ± 2.2 mm. The maximum pressure gradient of the aortic valve remained at 14.2-46.5 mmHg, 25.2 ± 10.2 mmHg on average, 1 or 2 months after surgery, but the LVMI significantly improved to 153.2 ± 33.9 g/m2 (p = 0.018). The hospitalization period were 24.7 ± 16.9 days for all the patients and 19.3 ± 5.1 days for patients undergoing the AVR alone. These results show that LVMI is significantly reduced by using a stentless bioprosthesis in the early phase after surgery, and early discharge from hospital can be expected by concurrently using minimally invasive cardiac surgery.