Repetitive nontreated episodes of grade 1B or 2 acute rejection impair long-term cardiac graft function

Episodes of grade 1B or 2 acute heart rejection are usually not treated, and most of them resolve spontaneously.

With the aim to assess long-term outcome in patients with repetitive nontreated episodes of low-grade (1B, 2) acute rejection, we have studied 141 heart transplant recipients in whom the evolutive pattern of acute rejection during the first 6 months after transplantation could be determined.

Forty-four patients (31%) had only grade 0 or 1A acute rejection episodes (pattern A); 23 patients (16%) had three or more episodes of grade 1B or 2 acute rejection without 3A or more advanced rejection (pattern B); 48 patients (34%) had one or two episodes of grade 3A, 3B, or 4 acute rejection only during the first 6 months after transplantation (pattern C); and 26 patients (19%) had three or more episodes of grade 3A, 3B, or 4 acute rejection (pattern D). Overall mortality was 11%, 26%, 19%, and 46% for patients with patterns A, B, C, and D, respectively. No difference was found among patterns with regard to incidence of graft atherosclerosis. Left ventricular ejection fraction at 1 year after transplantation was significantly lower (p < 0.05) for patients with pattern B (50% +/- 5% versus 59% +/- 7%, 59% +/- 11%, and 56% +/- 6% for patterns A, C, and D, respectively); cardiac index also was lower for patients with pattern B than for those with pattern A (3.6 +/- 0.6 versus 4.1 +/- 0.6 L/min/m2, p < 0.05).

Although mortality was higher for patients with more severe episodes of acute rejection, only repetitive nontreated episodes of grade 1B or 2 rejection significantly impaired long-term graft function.