Impact of transmurality and location on the diagnostic performance of 13N-ammonia PET in the detection of myocardial fibrosis - A hybrid PET/MR study.

Background: The influence of fibrosis transmurality and location on the diagnostic performance of positron emission tomography (PET) myocardial perfusion imaging (MPI) for detecting myocardial fibrosis remains unclear.

Methods And Results: One hundred patients with suspected or known coronary artery disease (n=50) or with a history of myocarditis (n=50) underwent simultaneous cardiac magnetic resonance (CMR) and 13N-ammonia PET imaging on a hybrid PET/MR device. CMR served as the reference with late gadolinium enhancement defining fibrosis of the left ventricular myocardium.