Around 6% of patients suffering an acute myocardial infarction (AMI) have normal coronary arteries. The mechanisms responsible are not fully known, but include hypercoagulable state, coronary endothelial dysfunction, aortic dissection, inflammation, coronary thrombosis, aortic wall stiffening, cocaine abuse, carbon monoxide poisoning and paradoxical embolism. Here, the case of a lifelong regular exerciser without risk factors for cardiovascular disease who suffered an AMI with normal coronaries is reported. Despite normal cardiac function on left ventriculography and echocardiography, late gadolinium enhancement by cardiac magnetic resonance (CMR) revealed significant cardiac necrosis. The long-term prognosis is favourable with low rates of coronary morbidity and mortality. Acute chest pain should not be considered as benign and warrants medical investigation.