Early and midterm results of model 300 CryoLife O’Brien stentless porcine aortic bioprosthesis

Abstract

Background. The Cryolife O’Brien (CLOB) is a composite stentless bioprosthesis constructed from noncoronary leaflets of three porcine aortic valves. This study aimed to investigate early and midterm results after aortic valve replacement with CLOB xenograft.Methods. Between 1993 and 2000, the CLOB was implanted in 125 patients (62 men; mean age 71.3 ± 6.4 years). Mean prosthesis size was 23.6 ± 2 mm. Mean follow-up time was 37.0 ± 12.1 months. Patients underwent echocardiographic studies preoperatively, at discharge, at 6 and 12 months postoperatively, and yearly thereafter.Results. Early (30-day) mortality rate was 2.4% (3 of 125 patients). Of the four late deaths, none was valve related. Actuarial 7-year survival was 93.6% ± 3%. Seven-year freedom from primary valve failure was 98.1% ± 1.8%. All patients showed an improvement of functional status (p < 0.001). ANOVA revealed a significant reduction over time in peak and mean systolic gradients (p < 0.001). Effective orifice area index increased (p < 0.001) and left ventricular mass index significantly reduced in all valve sizes (p < 0.001) during this time interval.Conclusions. Because the early and midterm results with CLOB xenograft have been satisfactory, we encourage its use as a valve substitute, particularly in patients with small aortic roots.