A congenital left ventricular aneurysm or diverticulum is a rare cardiac malformation described in 418 cases since the first description in 1816, being associated with other cardiac, vascular or thoracoabdominal abnormalities in about 75%. It appears to be a developmental anomaly, starting in the 4th embryonic week. Diagnosis can be made after exclusion of coronary artery disease, local or systemic inflammation or traumatic causes as well as cardiomyopathies. Clinically, most congenital left ventricular aneurysms and diverticula are asymptomatic, but some of them may cause systemic embolization, heart failure, valvular regurgitation, ventricular wall rupture, ventricular tachycardia, or sudden cardiac death. Diagnosis is established by imaging studies such as echocardiography, magnetic resonance imaging or left ventricular angiography, visualizing the structural changes and accompanying abnormalities. Mode of treatment has to be individually tailored and depends on clinical presentation, accompanying abnormalities and possible complications, options include surgical resection, especially in symptomatic patients, anticoagulation after systemic embolization, radiofrequency ablation or implantation of a cardioverter defibrillator in case of symptomatic ventricular tachycardias, occasionally combined with class I or III antiarrhythmic drugs. Because of the usually benign course of congenital left ventricular aneurysms and diverticula in the adulthood, most of them can be managed conservatively.