Predictive implications of bioptic diagnosis in cardiac allografts.

The prognostic value as represented by the predictive implications of the histopathologic bioptic diagnosis in cardiac allografts was studied in a total of 3209 biopsies from 111 patients under triple-drug immunosuppressive therapy after transplantation during a period of more than 2 years (0 to 782 days). The application of the so-called Hannover classification in the histopathologic diagnosis of rejection has revealed that there are certain configurations of histopathologic changes that lead significantly more frequently to the forms of acute rejection (moderate or severe) that require therapy. These are mild acute rejection with retrogressive changes in myocytes and a late-resolving phase of acute rejection with a severe vasculopathy. In cases with the simultaneous presence of the chronic phase of rejection, a slight prolongation of the interval taken by the conversion of these two diagnoses into the therapy-requiring forms of acute rejection could be observed. On average, however, the time interval of conversion of mild acute rejection with retrogressive changes in myocytes and of the late-resolving phase of acute rejection with interstitial vascular reaction into the therapy-requiring forms ranges between 7 and 10 days. Thus a second biopsy should be performed within this time interval.