Pericardial fat necrosis: an underdiagnosed cause of acute chest pain.

Pericardial fat necrosis (PFN) is a rare, benign cause of acute pleuritic chest pain, sharing symptomatic overlap with more serious cardiopulmonary conditions. We present a case of a woman in her early 50s who experienced progressive, left-sided pleuritic chest pain. Initial investigations, including an ECG, troponin and D-dimer, were negative. On re-presentation, inflammatory markers were raised and a small left pleural effusion was noted. CT pulmonary angiography, performed to exclude pulmonary embolism, revealed focal pericardial fat inflammation, retrospectively diagnosed as PFN. Follow-up imaging demonstrated complete resolution, consistent with the self-limiting nature of the condition. This case highlights the diagnostic challenge posed by PFN, given its non-specific symptoms which often mimic more serious acute pathology. Given that many patients undergo CT imaging as part of their work-up, awareness of PFN can prevent unnecessary, and potentially invasive, further investigations.