Results: Baseline characteristics for the healthy study group: The LV myocardium was significantly thicker in all segments for men compared with women. Mean segmental LVMT were 5.4±0.8mm for women and 6.6±0.9 mm for men. By multivariate analysis, male gender, age, body surface area, systolic blood pressure, hard physical activity, and smoking were significantly associated with thicker LV myocardium. The LV showed same overall geometrical patterns for men and women. However, the LV of women where significantly more heterogenic. LV geometry: Women Men Background: Left ventricular hypertrophy is associated with cardiovascular complications and geometry is important for prognosis. Computed tomographic coronary angiography (CTA) is increasingly being accepted as a key diagnostic modality for the non-invasive detection of coronary artery disease. Precise imaging of the cardiac geometry is available as a spin-off from each CTA, without increasing the imaging time, radiation exposure, or administered contrast media to the patient. Contact: Louise Hindsø, Email: louisehindsoe@hotmail.com, Phone: +45 51948114 Methods: 4,295 participants from the Copenhagen General Population Study were randomly enrolled in a MDCT sub study and a CTA were performed in late diastole. We defined a healthy study group (n=805) by following exclusion criteria: [1] evidence of cardiopulmonary disease, [2] hypertension, [3] subjects taking prescription medications for cardiovascular disease [4] overweight defined as BMI ≥25, and [5] diabetes. Images were analyzed by semi-automatic computer software, Vitrea 6.3, and regional left ventricular thickness was assessed using the American Heart Association 17 segment Model. The 17th segment was excluded due to artefacts. LV geometry was illustrated, by dividing segmental thickness, in each individual segment, with mean overall thickness of the LV. Conclusion: The normal human heart was found to be morphologically heterogenic, and significantly more heterogenic for woman than men. This study provided gender specific reference values for regional LVMT and LV geometry, derived with MDCT in a healthy population. The aim of this study was to derive reference values of regional LV myocardial thickness (LVMT) and geometry, with the use of 320-detector computed tomography (MDCT). Moreover, we wanted to determine gender related differences. Regional left ventricular myocardial thickness and geometry – assessed with 320-detector computed tomographyin a healthy population in a healthy populationL Hindsø L Hindsø1,21,2, A Fuchs, A Fuchs11, T Kühl, T Kühl11, BG Nordestgaard, BG Nordestgaard3,43,4, L Køber, L Køber1,31,3, KF Kofoed, KF Kofoed1,21,21: Department of Cardiology, 1: Department of Cardiology, RighospitaletRighospitalet, University of Copenhagen, Denmark, University of Copenhagen, Denmark2: Department of Radiology, 2: Department of Radiology, RighospitaletRighospitalet, University of Copenhagen, Denmark, University of Copenhagen, Denmark3: 3: Faculty of Health Sciences, University of Copenhagen, Denmark 4: Department of Clinical Biochemistry, Herlev Hospital, University of Copenhagen, Denmark Characteristics Men (n=276) Women (n=529) P-value Age (years) 57 (10) 55 (9) 0.04 Height (cm) 180 (7) 167 (6) <0.01 Weight (kg) 75 (7) 63 (6) <0.01 BMI (kg/m2) 23 (1) 22 (2) <0.01 BSA (m2) 1.9 (0.1) 1.7 (0.1) <0.01 Systolic BP (mmHg) 128 (10) 125 (12) <0.01 Diastolic BP (mmHg) 77 (7) 76 (8) 0.23 Smoking Former 42 (15%) 77 (15%) 0.79 Current 115 (42%) 204 (38%) 0.38 Hard physical activity 53 (19%) 39 (7%) <0.01