Objectives: Surgical repair of submitral aneurysms presents a technical challenge especially if the mitral valve (MV) apparatus is involved. We present our single center surgical experience and the potential of multi-slice computed tomography (MSCT) in the assessment of aneurysm morphology and changes in MV and LV geometry. Methods: In 05/06-04/12, 21 patients (m:w=17:4, ages 39 to 78, mean 63 yrs; mean NYHA class 2.8) with submitral LV aneurysm were operated upon. Echocardiography and MSCT (Somatom Definition, Siemens) were performed before and after surgery. LV and aneurysm end-diastolic/end-systolic volume were measured and indexed to body surface area (LV-EDVI/LV-ESVI, A-EDVI/A-ESVI). LV ejection fraction (LVEF), cardiac output (CO) and cardiac index (CI) were calculated on the basis of MSCT data. MV geometry was characterized by mid-systolic coaptation distance (CD), tenting area (TA) and MV closure angle (MVCA). Results: Thirty-day and 5-year survival was 88.9%±7.4% and 82.1%±9.5%. Aneurysms were localized in myocardial segments 4/10/11. Preoperative A-EDVI showed a slight systolic increase, demonstrating adverse volume shift. There was reduction of LV-EDVI (141.4±21.6 to 72.7±12.9 ml/sqm, p=0.006) and LV-ESVI (102.2±24.9 to 42.5±9.9 ml/sqm, p=0.024), LVEF improvement (32% to 45%, p=0.016) and significant increase in CO and CI after surgical repair. Mitral repair/replacement was necessary in three patients. Postoperative reduction of mitral regurgitation (from grade 0.94 to 0.24, p=0.003) corresponded with improvement of MV geometry (CD (reduced from 10.2 to 7.9 mm, p=0.06) and of TA (1.8 to 1.5 sqcm, p=0.04) and MVCA (103° to 116°, p=0.04). Conclusions: Reconstruction of submitral LV aneurysms can be performed with good mid-term results. MSCT provides valuable information about aneurysm localization, its extent and effect on MV and LV geometry and reverse remodeling, and also functional changes after surgical restoration.