AORTIC-VALVE REPLACEMENT WITH TIME FREESTYLE STENTLESS XENOGRAFT

We performed aortic valve replacement with the Freestyle stentless xen ograft in 55 consecutive patients requiring a bioprosthesis. Thirty-fo ur were male and 21 female, and all were in New York Heart Association class III to V. Ages ranged from 44 to 87 years (median, 74 years). F ifteen patients required coronary bypass grafts. One required mitral v alve replacement (after attempted repair) and another needed repair of both. the mitral and tricuspid valves. Four were reoperations. Implan tation involved two-thirds transection at the aortic sinotubular junct ion and insertion of the xenograft cylinder into the aortic sinuses. I schemic times ranged from 34 to 58 minutes for isolated aortic valve r eplacement and up to 79 minutes for aortic plus mitral valve replaceme nt. Two patients died in the hospital of left ventricular failure. Sur vivors underwent echocardiographic assessment of systolic gradients. T he mean gradients for valve sizes of 21, 23, 25, and 27 cm were 13, 10 , 8, and 6.5 mm Hg, respectively. No patient had more than trivial reg urgitation. One died late of left ventricular failure. The Free-style stentless xenograft is user friendly and can be employed in a calcifie d root. The ''cylinder within a cylinder'' method is simple and reprod ucible and avoids aortic regurgitation. Follow-up has shown excellent hemodynamic function and decreasing gradients.