Cardiovascular magnetic resonance imaging in asymptomatic acute heart rejection: a case report

Diagnosis of rejection is a major objective in the management of heart transplant recipients. It has been reported that one-third of protocol biopsies in asymptomatic, biochemically stable organ transplant recipients in the first 6 months show unsuspected subclinical graft rejection.

We present the case of a 43-year-old man suffering from dilated cardiomyopathy who underwent orthotropic heart transplantation. The patient was admitted for a protocol endomyocardial biopsy and magnetic resonance imaging (MRI) on the 4th postoperative month as a protocol procedure. The examination revealed clinical status NYHA I with no signs of fatigue, diminution of exercise tolerance, or shortness of breath. His body temperature was not raised. He was referred for endomyocardial biopsy and cardiovascular magnetic resonance (CMR) imaging. CMR imaging showed good left and right ventricle function and contractility. T2 imaging revealed increased signal in the area of the right ventricular free wall, seen both in 4-chamber and short axis views. The patient underwent an endomyocardial biopsy, which demonstrated diffuse infiltrate with multifocal miocyte damage and cellular edema recognized as acute rejection (3a ISHLT grade). Consequently, he was treated with parenteral methylprednisolone administration. The CMR study performed after 1 week of therapy showed that the signal intensity of the edematous areas was significantly decreased. Repetitive endomyocardial biopsy revealed no signs of rejection.

CMR can be helpful in graft monitoring following heart transplantation. It gives a whole-heart perspective that can be competitive with and/or complementary to endomyocardial biopsy. As a noninvasive study it can be applied more often and facilitates diagnosis of asymptomatic rejection episodes.