Initial Experience with the Medtronic ADVANTAGE Valve Prosthesis in the Mitral Position - Clinical Outcome and Analysis of Complications

Abstract

The Medtronic ADVANTAGE prosthetic heart valve is a bileaflet mechanical heart valve which has two main design modifications. The prosthesis has an enlarged central orifice to improve blood flow characteristics and an asymmetric butterfly pivot recess with expanded outflow component designed to enhance the blood flow washing through the pivot region. This report summarizes the initial experience with 55 patients who underwent isolated mitral valve replacement. We prospectively followed 55 patients undergoing mitral valve replacement with the Medtronic ADVANTAGE prosthesis in a single center study. All patients were operated on via a median sternotomy and a left atrial approach. The age of the patients at implant ranged from 42 years to 77 years with a mean of 61.8 years. Forty-five percent of the patients were male. Seventy-five percent of the patients were in NYHA functional class III or IV prior to valve replacement. The diameters of the implanted prostheses were as follows: 25 mm in 2 patients, 27 mm in 12 patients, 29 mm in 20 patients, and 31 mm in 21 patients. Coronary artery bypass grafting was performed with valve replacement in 16.4 % of patients and additional tricuspid repair in 10.9 %. After one year, 97.6 % and after two years 100 % of the included patients were in NYHA functional class I or II. All patients had Coumadin (warfarin) therapy postoperatively with a target INR range of 2.5 to 3.5, or 3.0 to 4.0. There were 4 thromboembolic events (7.3 %) in the early period and 2 late events (2.6 %). Episodes of valve thrombosis were not seen during the follow-up, which consisted of 76.5 patient years. The hemodynamic performance was favorable and within clinically acceptable ranges. The incidence of valve-related mortality and morbidity in this preliminary study was extremely low, indicating good clinical results comparable to those reported for other bileaflet valves. The ADVANTAGE valve is a safe and effective option for mitral valve replacement with a very low incidence of valve-related complications.