CMR in the diagnosis of acute pericarditis

Abstract

Background Acute pericarditis is the most common condition affecting the pericardium. Diagnosis has historically been based upon a combination of clinical history, examination, ECG findings, inflammatory markers and echocardiographic findings of pericardial thickening and effusion. Literature on the role of CMR and the appearances of acute pericarditis is limited. Method All patients with a clinical diagnosis of acute pericarditis and who had a cardiovascular magnetic resonance (CMR) examination from January 2006 to June 2010 were retrospectively evaluated from a high-volume center (performing 6,230 CMR studies during this period) Patients with confirmed myocarditis or myocardial infarction, or previous cardiac surgery were excluded. Age and sex matched controls were obtained from the department’s database. Images were blindly evaluated by an expert radiologist with SCMR level 3 experience. Pericardial thickness was measured on T2 black blood DIR images to minimize artifact from chemical shift. Pericardial enhancement on late gadolinium enhancement (LGE) images was graded from 0-3 (0=absent, 3=intense enhancement). Pericardial effusions were graded as physiological (trivial/small) vs pathological (medium or large). The presence of pleural effusions was also recorded. Results CMR images from 21 patients with clinically confirmed acute pericarditis were reviewed. Pericardial thickness was significantly increased in patients with pericarditis compared with controls 2.35 +/- 0.54mm vs 1.77 +/0.34mm (p<0.05). Pericardial LGE was demonstrated in 19 (86%). Of these, 12 (63%) had intense, 5 (26%) moderate, and 1 (5)% mild LGE. In comparison no controls had significant LGE. There was a strong