Role of routine endomyocardial biopsy to monitor late rejection after heart transplantation.

Endomycardial biopsy remains the standard used to monitor rejection after heart transplantation. There is, however, no consensus as to how often surveillance endomyocardial biopsy should be carried out after heart transplantation. We have analyzed 131 patients undergoing orthotopic heart transplantation during the first 4 years of the transplant program at St. Vincent's Hospital. The majority of endomyocardial biopsies that showed acute rejection occurred in the first 3 months after transplantation; after 9 months only 2.5% of endomyocardial biopsies performed showed rejection. Of those patients with rejection, 47% had symptoms. Seven patients experienced late rejection and all made a good recovery with normal cardiac function. We conclude that the incidence of acute rejection decreases significantly more than 3 months after-transplantation; after 9 months only 2.5% of endomyocardial biopsies will show rejection. Of these, 47% will be associated with symptoms. On the basis of experience, we believe that in our own unit, endomyocardial biopsy more than 9 months after transplantation seems unwarranted unless clinically indicated.