We report a case of spontaneous coronary artery rupture (SCAR) in a 43-year-old male who presented with symptoms of sudden onset of chest pain and hemodynamic collapse. There were no abnormal electrocardiogram changes and serum troponin was not detected. Acute aortic dissection was suspected but urgent contrast computed tomography (CT) showed a large pericardial effusion with cardiac tamponade. This was later confirmed on trans-oesophageal echocardiogram. The SCAR was seen intra-operatively as an isolated perforation of the posterior descending artery. The patient was successfully managed with direct repair under cardiopulmonary bypass. Postoperative multi-detector dual-source 64-slice CT coronary angiography revealed normal coronary arteries with absence of atherosclerotic plaque in all coronary arterial segments. It is concluded that, though rare, a differential diagnosis of SCAR should be considered in cases of acute chest pain with cardiac tamponade in adult patients of all ages.