Post-infarction ventricular aneurysm is a complication of myocardial infarction. While the involvement of the anterior wall is quite common, posterobasal left ventricular aneurysm is a rare clinical complication in this setting. In this case report, we report a post-infarction posterobasal left ventricular aneurysm combined with ischemic mitral regurgitation due to coronary artery disease, for which we successfully performed triple coronary artery bypass and ventricular geometry restitution via a modified Dor's procedure with mitral valve replacement through an extracardiac approach.1.