This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Yun, K. L. Articles by Khonsari, S. Search for Related Content PubMed PubMed Citation Articles by Yun, K. L. Articles by Khonsari, S. Related Collections Valvular heart disease Catheter-based coronary and valvular interventions: other Echocardiography CV surgery: aortic and vascular disease

(Circulation. 1999;100:II-17.)
© 1999 American Heart Association, Inc.

Surgery for Valvular Heart Disease

Aortic Valve Replacement With the Freestyle Stentless Bioprosthesis

Five-Year Experience

Kwok L. Yun, MD; Colleen F. Sintek, MD; Alden D. Fletcher, MD; Thomas A. Pfeffer, MD; Gary S. Kochamba, MD; Manly R. Hyde, MD; Jesus O. Torpoco, MD; Siavosh Khonsari, MD

From the Department of Cardiac Surgery, Kaiser Permanente Medical Center, Los Angeles, Calif.

Correspondence to Kwok L. Yun, MD, Department of Cardiac Surgery, Southern California Permanente Medical Group, 1526 N Edgemont St, 3rd Floor, Los Angeles, CA 90027. E-mail Kwok.L.Yun{at}KP.org

Background—Stentless aortic valves were designed to provide a more physiological flow pattern and lower transvalvular gradient, which may have an important bearing on postoperative left ventricular function and remodeling. In this study, we prospectively analyzed the 5-year clinical results with the Freestyle valve (Medtronic, Inc) and its hemodynamic performance by serial echocardiography.

Methods and Results—Between January 1993 and August 1997, 95 patients with a mean age of 75 years underwent aortic valve replacement with the Freestyle prosthesis. Sixty-four percent of patients received valves 23 mm, and 37% had concomitant coronary artery bypass grafting. Average follow-up was 44±18 months (mean±SD), and echocardiography was performed preoperatively, at discharge, at 3 to 6 months, and annually thereafter. The 30-day operative mortality rate was 3%, with an overall actuarial survival rate of 80±6% (mean±SEM) at 5 years. Of the 10 late deaths, only 2 were cardiac related, thereby yielding a freedom from cardiac mortality of 94±3% after 5 years. No patient required reoperation on the aortic valve for any reason, including structural degeneration, nonstructural dysfunction, or prosthetic valve endocarditis. There were 9 thromboembolic and 3 anticoagulant-related bleeding events, none of which was fatal. The actuarial freedom from valve-related morbidity and mortality was 79±4% at 5 years. Hemodynamically, the mean transvalvular gradient significantly decreased after valve replacement and was reduced further by 41% by 6 months with a corresponding increase in effective orifice area. Left ventricular mass index fell to 75% of the preoperative value by 2 years.

Conclusions—The Freestyle stentless valve can be implanted safely in the elderly with excellent midterm clinical results. It has superb hemodynamics in terms of residual transvalvular gradient, effective orifice area, and regression of left ventricular hypertrophy.

Key Words: valves • hemodynamics • echocardiography • survival