ACCELERATED DEGENERATION OF ALLOGRAFTS IN THE FIRST 2 YEARS OF LIFE

Between January 1988 and May 1994, 53 of 159 patients have received cr yopreserved aortic and pulmonary allografts for reconstruction of the pulmonary circuit in the first 2 years of life with body weight rangin g from 2.2 to 18 kg (mean, 8.2 +/- 3.4 kg). The implanted allografts r anged in internal diameter from 9 to 23 mm (mean, 16.3 +/- 3.5 mm). Of the 38 survivors who regularly had postoperative echocardiographic ex aminations 15 (39.5%) underwent cardiac catheterization 1 to 31 months after operation. Allograft dysfunction (gradient greater than or equa l to 50 mm Hg with or without pulmonary insufficiency) was confirmed. in 9 patients leading to reoperation in 5 and valvulo-angioplasty in 4 . At 48 months actuarial survival was 64%. In the aortic and pulmonary allografts freedom from wall calcification at 20 months was 19% and 1 00%, respectively. Freedom from valve dysfunction in patients with aor tic and pulmonary allografts was 53% and 88%, respectively; it was 49% in allografts with an internal diameter of 17 mm or smaller. Freedom from reoperation in ail patients was 78%. In conclusion, young age, an tigenicity (ABO compatibility), and type of allograft seemed to be ind ependent risk factors for early allograft conduit degeneration and lat e valve dysfunction. Pulmonary allografts seemed to be more resistant to early wall calcification and valve dysfunction than aortic allograf ts.