TORONTO STENTLESS AORTIC-VALVE REPLACEMENT IN ELDERLY PATIENTS

From July 1992 to October 1994, we inserted new Toronto SPV stentless aortic heterografts (SJM Med, Inc., St Paul, Minneapolis, USA) in 40 o f a series of 50 consecutive patients older than 70 years. The mean ag e was 75.7 years (range 70 - 86 years). All, except 4 patients, were p re-operatively in NYHA functional class III or higher. The aortic clam p time was significantly higher in the stentless group (75 v. 53 minut es, P < 0.001). The average 255 mm size of the implanted valves stands in stark contrast to the low body surface area (1.69 m(2)) of this pa tient group. The surgeon's (in)experience was the major reason for the drawbacks (5/50) associated with a stentless procedure. The follow-up period ranged from 2 to 27 months and was complete in 100% of cases. We encountered 1 hospital death and no late deaths (97.5% actuarial su rvival). The mean NYHA class at follow-up was 1.5, and without excepti on patients were in class I or II. We noted one transient ischaemic at tack immediately postoperatively and another later incident in a patie nt with a previous severe vascular history. With a low-intensity antic oagulation regimen for the first 3 months, there were two incidents of haemorrhaging necessitating premature anticoagulation withdrawal. Ech ocardiographic transthoracic valvular gradients compared favourably wi th the reported gradients of other biological valves, especially the s maller ones and significantly better haemodynamics were noted in most cases 6 months after implantation. Comparison of data with stented val ves implanted during the same period indicates that the average size o f the stentless valves was significantly higher (223 v. 255 mm, P < 0. 001) in an equivalent population.