BACKGROUND: Computed tomography (CT) criteria for eligibility for right anterior mini-thoracotomy (RAMT) with regard to the assessment of the ascending aorta and AV position and depth are previously described in the literature. Sites reported percentage of patients undergoing aortic valve replacement (AVR) using RAMT approach di"er between institutions depending on multiple factors. We evaluated anatomic di"erences in first 54 patients, who underwent preoperative CT scanning during learning curve METHODS: 54 all comers selected for isolated AVR underwent preoperative CT scan. In 28 RAMT approach was selected and in 26 upper partial sternotomy. Image interpretation was performed from reconstruction of axial and sagittal source images. CT criteria used for the purpose of this analysis were: percentage of aortic diameter positioned on the right in respect to a vertical line drawn from the right sternal border to the ascending aorta; distance from skin to ascending aorta along vertical line drawn from the right sternal border; the angle between the midline and the inclination of ascending aorta (α angle), aortic annulus size. RESULTS: Selected CT parameters were not statistically di"erent between groups.CONCLUSIONS: CT measurements did not di"er significantly between groups. Patients were selected predominanlty based on aortic annulus size.