Aortic valve replacement with Medtronic Freestyle Bioprosthesis: Operativetechnique and results

Objective: This study evaluates the initial results for safety and efficacy of aortic valve replacement (AVR) using the Medtronic Freestyle Bioprosthe sis. Methods: One hundred three patients underwent AVR with the Medtronic F reestyle Bioprosthesis over a 40-month period. There were 59 male and 44 fe male patients with a mean age of 74 years (range 36 to 88 years). Valve siz e ranged from 19 to 27 mm, and all valves were implanted using a freehand s ubcoronary technique. Anticoagulation with coumadin was only used for atria l fibrillation. Aspirin was given to patients with associated coronary arte ry disease. Echocardiography to assess transvalvular pressure gradient and effective valve orifice area was performed at discharge, 3 to 6 months, 1 y ear, and then annually. Results: There were 4 (3.9%) deaths within 30 days of operation and 5 (4.9%) late deaths. Two (1.9%) deaths were valve-related , one from commissural dehiscence and one from bacterial endocarditis. Thre e (2.9%) deaths, two early and one late, were from other cardiac causes. Th e re maining deaths were from noncardiac causes. Five (4.9%) patients suffe red a thromboembolic event, two had permanent neurological deficits, two ha d transient neurological events, and one had coronary artery occlusion. Mea n transvalvular gradient assessed by echocardiography was low at all time i ntervals: discharge (12.8 mmHg), 3 to 6 months (11.3 mmHg), 1 year (12.0 mm Hg), and 2 years (11.6 mmHg). Mean effective valve orifice area was good at all time intervals: discharge (1.4 cm(2)), 3 to 6 months (1.5 cm(2)), 1 ye ar (1.6 cm(2)), and 2 years (1.6 cm(2)). Of the 38 patients assessed by ech ocardiography at 1 year, 33 (87%) had no or trivial valve incompetence and the remainder had mild valve incompetence. Conclusions: Aortic valve replac ement with the Medtronic Freestyle Bioprosthesis has a low incidence of ear ly valve-related mortality and thromboembolism. The bioprosthesis demonstra tes good hemodynamic performance even in small diameters and is particularl y well suited for older patients and the small aortic root.