Objective: The aim of this study is to debate the current status and justification for continued use of stentless valves, outlining the clinical results with the CryoLife-O'Brien composite porcine stentless valve™ (CLOB). Material And Methods: Between December 1992 and February 2000, 307 patients underwent aortic valve replacement with a CLOB valve. The mean age was 73 years (range 59-89 years with 16% being 80 years and over). All patients were assessed clinically and by echocardiography postoperatively at 6 days, 6 months, 12 months and yearly thereafter. Results: The hospital mortality was 1.3% (4 valve-unrelated cases). Late mortality occurred with 28 patients (9.2%), of which only 2 were valve-related (late endocarditis). Morbid events have included 2(0.6%) perioperative strokes, 2 (0.6%) perivalvar leaks, 6 (1.9%) endocarditis and 1 (0.3%) structural deterioration. Reoperation was required in 6 patients (1.9%): 3 for endocarditis, 2 for perivalvar leak and 1 for structural deterioration. Serial echocardiography demonstrated a mean gradient of 7mmHg with a very low incidence of trivial incompetence on Doppler, and significant left ventricular hypertrophic regression (p=0.05). Conclusion: Stentless valves have produced excellent early and mid-term results. However, surveillance is required to determine the durability at 10 to 12 years, a time when stented porcine valves begin to show failure from structural deterioration.
Heart valve prosthesis; Heart valve prosthesis implantation
