Paradoxical embolism in coronary artery is a rarely diagnosed clinical entity. In the majority of reported cases; the diagnostic of this pathology is « presumptive » based on certain criteria. It can be considered "proven" when the embolus is found lodged in the abnormal communication between the venous and arterial circulation; which is very rare. We herein report a case of myocardial infarction caused by a proven paradoxical coronary embolism through a patent foramen ovale. The authors highlight through this paper the contribution of echocardiography and particularly trans-esophageal echocardiography, especially if performed soon after presentation, for early diagnosis.