Ultrasonic Studies for the Early Detection of Acute Cardiac Rejection1,2

SUMMARY Cardiac dimensions were measured serially using recently developed ultrasonic echographic techniques in 12 patients after orthotopic cardiac allotransplantation. Changes in the echographic measurement were noted in 20 of the 26 episodes of acute rejection that were diagnosed by other methods during the period of study. Increased posterior left ventricular wall thickness and right ventricular dilation were the changes most often observed during acute rejection, and these changes were reversed by successful immunosuppressive therapy. While false positive diagnoses were noted relatively frequently by the echographic criteria employed in this study, this did not detract significantly from the clinical utility of the technique. Directional changes in cardiac dimensions noted with echography are consistent with the known histopathological and pathophysiological changes in the cardiac graft during acute immunological rejection. The echographic technique used in this study is atraumatic and easily repeatable, suggests early stages of the rejection process, and is moderatelv reliable in indicating rejection.