The electrocardiogram recording, when an acute coronary syndrome is suspected, is of paramount importance as the modifications of the ST segment confirms the diagnosis of STEMI (ST-elevation myocardial infarction) which needs immediate treatment, or NSTEMI (Non-ST elevation myocardial infarction). In case of NSTEMI, the invasive procedure is generally performed in the first 24 to 72 hours. However, one patient in four present an acute occluded artery at the time of the coronary angiography and this is associated with a worse outcome. In this article, we describe an emblematic case, discuss the worse outcome of these patients and explore some ways to prevent this problem.