A young female athlete is described with anomalous origin of the main stem of the left coronary artery from the non-facing sinus of Valsalva who sustained myocardial infarction and died suddenly after physical exertion. Autopsy findings illustrated the mechanistic importance of acute angle take-off of the left main coronary artery and a slit-like orifice, which was likely compressed and obstructed by acute expansion of the aortic wall. This rare type of coronary anomaly has been regarded as having little clinical significance, but it can lead to sudden cardiac death under physical exertion.
