Optimal results of aortic valve replacement with small mechanical valves (< 19 mm).

BACKGROUND AND AIM OF THE STUDY: Controversy exists regarding the optimal operative method or type of prosthesis for patients with a small aortic root. The aim of this retrospective study was to investigate the early and mid-term outcomes of standard aortic valve replacement (AVR) using 16 mm or 18 mm ATS Advanced Performance (AP) or 17 mm St. Jude Medical (SJM) Regent valves for a small aortic root.
METHODS: Between April 2003 and August 2009, 78 patients (age range: 50-86 years; 86% aged > or = 65 years) underwent AVR with 16 mm or 18 mm ATS AP valves (16AP group: n = 21, 18AP group: n = 32), or a 17 mm SJM Regent valve (17Regent group: n = 25). Fifty-six patients (72%) had a body surface area (BSA) of < 1.5 m2; the BSA in the 16AP group was significantly smaller than in the other two groups. The early and mid-term outcomes, and the hemodynamic performance of the prostheses, were evaluated and compared among the groups.
RESULTS: No operative deaths were observed in the 16AP and 17Regent groups, but one hospital death occurred in the 18AP group. During follow up, there were four cardiac-related deaths (two patients each in the 16AP and 18AP groups). Although the postoperative pressure gradient of the 16AP group was significantly higher than that of the 18AP group, the left ventricular mass in all groups was decreased significantly during follow up, but the extent of left ventricular mass regression was similar among the groups (-30%, -25% and -28% in the 16AP, 17Regent and 18AP groups, respectively; p = 0.844).
CONCLUSION: The early and mid-term results of AVR with 16 mm or 18 mm ATS AP valves, or with a 17 mm SJM Regent valve, were satisfactory. Therefore, standard AVR using these small mechanical prostheses, which avoids the need to enlarge the annulus or to conduct stentless bioprosthesis implantation, might represent an acceptable method, especially in elderly patients with a small aortic root.