Rupture of the left ventricle wall is a fatal complication of myocardial infarction, with a significant hospital mortality of up to 80% [
1]. This complication is rare, and its incidence has decreased progressively and in parallel with the improvement of myocardial reperfusion strategies [
2] and the early use of drugs, especially low-molecular-weight heparin and beta blockers [
1]. Incidence has decreased from 4 to 0.2% [
1]. Rupture of the anterior wall is more serious than rupture of the posterior wall because it is more likely to cause a hemopericardium, whereas rupture of the posterior wall often enables the generation of an inflammatory reaction of the posterior pericardium at the origin of pericardial adhesions and the development of a pseudoaneurysm [
3]. Posterior pseudoaneurysms are the most frequent, accounting for 83% of false aneurysms [
4]. Pseudoaneurysm is sometimes associated with other mechanical complications, such as significant mitral insufficiency (by reaching the posterior papillary muscle) [
5] and interventricular communication [
6]. These pseudoaneurysms may be asymptomatic (> 10%) [
7] or present with nonspecific signs such as congestive heart failure, angina, rhythm disturbances, or thromboembolic events, which occur after a variable delay of the acute event, after an average of 50 days [
8]. Thus, pseudoaneurysm is rarely diagnosed in the clinic. It is important to know how to distinguish between an aneurysm and a pseudoaneurysm because the therapeutic cares differ. Left ventricular angiography associated with coronary angiography was the reference examination to confirm the diagnosis of LV pseudoaneurysms and to assess the need for associated coronary bypass [
7]. Transthoracic ultrasound is currently the reference. It provides important information regarding the anatomy and localization of the defect and the presence of a thrombus or associated valvulopathy. It can also assess left ventricular function and look for pericardial effusion. Transesophageal ultrasound appears to provide more information than transthoracic ultrasound, especially in terms of posterior pseudoaneurysms [
9]. Meanwhile, the diagnosis is not always obvious. Zoffoli
et al. [
5] had therefore established certain ultrasound and angiographic criteria making it possible to differentiate between false and true aneurysms. MRI has 100% sensitivity and a good negative predictive value. It successfully identifies thrombi and delayed enhancement of pericardium [
10]. The European Society of Cardiology recommends transthoracic ultrasound as the first-line examination to confirm pseudoaneurysms and suggests that MRI can complement the diagnosis by identifying the contained cardiac rupture and its anatomical features to guide surgical intervention [
11]. In our patient, MRI provided us with additional information regarding the presence of thrombus and the viability of the myocardium of the affected territory. Urgent surgery is the best treatment given the risk of embolization and rupture of pseudoaneurysms, which is of the order of 30–45% [
7]. It consists of an aneurysmectomy and patch closure. However, the risk of recurrence of these pseudoaneurysms still exists, and 5-year survival is only about 60% [
8]. Some cases of percutaneous closure for patients at high surgical risk have been described with good results [
12]. There are some who have even opted for conservative treatment [
13].