Primary aortic valve replacement with allografts over twenty-five years: Valve-related and procedure-related determinants of outcome

Objectives: Allografts offer many advantages over prosthetic valves, but al lograft durability varies considerably. Methods: From 1969 through 1993, 61 8 patients aged 15 to 84 years underwent their first aortic valve replaceme nt with an aortic allograft. Concomitant surgery included aortic root tailo ring (n = 58), replacement or tailoring of the ascending aorta (n = 56), an d coronary artery bypass grafting (n = 87). Allograft implantation was done by means of a "freehand" subcoronary technique (n = 551) or total root rep lacement (n = 67). The allografts were antibiotic sterilized (n = 479), cry opreserved (n = 12), or viable (unprocessed, harvested from brain-dead mult iorgan donors or heart transplant recipients, n = 127). Maximum follow-up w as 27.1 years. Results: Thirty-day mortality was 5.0%, and crude survival w as 67% and 35% at 10 and 20 years. Ten- and 20-year Fates of freedom from c omplications were as follows: endocarditis, 93 % and 89 %; primary tissue f ailure, 62% and 18%; and redo aortic valve replacement, 81% and 35%. Multiv ariable Cox analyses identified several valve- and procedure-related determ inants: rising allograft donor age and antibiotic-sterilized allograft for mortality; donor more than 10 years older than patient for endocarditis; ri sing donor age minus patient age, rising implantation time (from harvest to aortic valve replacement), and donor age more than 65 years for tissue fai lure; and rising donor age minus patient age, young patient age, rising imp lantation time, and subcoronary implantation preceded by aortic root tailor ing for redo aortic valve replacement. Estimated 10- and 20-year rates of f reedom from tissue failure for a 70-year-old patient with a viable valve fr om a 30-year-old donor and no other risk factors were 91% and 64%; the figu res were 71% and 20% if the donor age was 65 years. The rates of freedom fr om tissue failure for a 30-year-old patient with a 30-year-old donor were 8 2% and 39%; the figures were 49% and 3% with a 65-year-old donor. Beneficia l influences of a viable valve were largely covered by short harvest time ( no delay for allografts from brain dead organ donors or heart transplant re cipients) and short implantation time. Conclusions: Primary allograft aorti c valve replacement can give acceptable results for up to 25 years. The lat e results can be improved by the use of a viable allograft, by matching pat ient and donor age, and by more liberal use of free root replacement with r e-implantation of the coronary arteries rather than tailoring the root to a ccommodate a subcoronary implantation.