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

Background. The Cryolife O'Brien (CLOB) is a composite stentless bioprosthe sis constructed from noncoronary leaflets of three porcine aortic valves. T his 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 echocardio graphic studies preoperatively, at discharge, at 6 and 12 months postoperat ively, 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). ANO VA revealed a significant reduction over time in peak and mean systolic gra dients (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, particularl y in patients with small aortic roots. (C) 2001 by The Society of Thoracic Surgeons.