We describe the first reported case of active pericarditis diagnosed by positron emission tomography (PET) and cardiac magnetic resonance (CMR) fusion imaging.
A 68-year-old female presented with chest pain. She has a remote history of localized breast cancer treated with bilateral mastectomy and adjuvant chemotherapy, without radiotherapy. A myocardial stress perfusion study was negative for ischaemia. Given her history of breast cancer, 18-fluorodeoxyglucose PET imaging was performed. This demonstrated diffuse hypermetabolic activity in the pericardium. There were no other metabolically active foci to suggest metastatic disease. Her serum inflammatory markers were significantly elevated: ultra-sensitive C-reactive protein of 64.8 (<3.1 mg/dL); Westergren sedimentation rate of 26 (0–20 mm/h). Cardiac magnetic resonance was performed to investigate the suspicion of active pericarditis as the cause of her chest pain, which demonstrated significantly increased pericardial signal on short-tau inversion recovery (STIR) imaging, consistent with pericardial oedema. On delayed-enhancement imaging, there was significantly increased pericardial signal, consistent with active pericardial inflammation. Subsequently, fusion of PET and CMR imaging, demonstrated regions of increased pericardial metabolic activity corresponding to regions of increased signal on STIR and delayed-enhancement imaging. These findings are consistent with active pericarditis with pericardial inflammation/oedema and increased metabolic activity. The patient was treated with ibuprofen and colchicine. At 1-month follow-up, she has dramatically improved clinically, with resolution of symptoms and normalization of inflammatory markers. This case highlights the additive utility of the combination of PET and CMR imaging in diagnosing active pericarditis.
Active pericarditis on positron emission tomography (PET) and cardiac magnetic resonance (CMR) imaging: short-tau inversion recovery CMR imaging demonstrated significant pericardial oedema at the basal (A), mid (D), and apical (G) levels; corresponding fat-suppressed phase-sensitive inversion recovery late gadolinium enhancement MRI sequence demonstrated significant pericardial delayed-enhancement at the basal (B), mid (E), and apical (H) levels; 18-fluorodeoxyglucose PET/CMR fusion images demonstrated increased pericardial metabolic activity corresponding to that seen on CMR imaging at the equivalent basal (C), mid (F), and apical (I) levels.
