Wellens syndrome is an acute coronary syndrome with a high risk of life-threatening myocardial ischaemic disease. It should be emphasised that it is not always an acute process, and may manifest itself over periods of weeks and result in an Impending Acute Myocardial Infarction of the anterior wall. The aim of this research lies in the importance of detecting this pathology in a timely manner, because, although it is infrequent, it has a high mortality rate in patients who present it and do not have an early detection.