BACKGROUND: Two-dimensional Doppler echocardiography from transthoracic approach is the accepted tool to examine expected pathologies of the aortic valve (AV) in the daily clinical routine. Three-dimensional speckle-tracking echocardiography (3DSTE) is known to be one of the newest cardiovascular imaging modalities, which is mostly used for cardiac chamber quantifications including volumetric and strain assessments. However, capability of 3DSTE in 'en-face' assessment of valvular annuli has also been demonstrated as a potentially valid imaging alternative for AV annular (AVA) assessments as well. Considering the importance of the AV and its pathologies, it has been found to be important to present the 3DSTE-derived normal reference values of AVA dimensions in a healthy adult population in different ages and genders. METHODS: The present cohort study comprised 251 adult Caucasian healthy individuals. Due to inferior image quality during 3DSTE, 101 cases were excluded (40%); hence, the final number of cases proved to be 150, with a mean age of 34.8±12.3 years (82 males). This population has been further divided according to their age: 18-29 years (n=67; mean age: 24.6±2.7 years, 35 males), 30-39 years (n=40; mean age: 33.8±2.8 years, 29 males), 40-49 years (n=18; mean age: 43.1±3.8 years, 11 males) and 50+ years (n=25, mean age: 57.3±4.9 years, 7 males). RESULTS: Females have lower AVA dimensions than males, but the difference disappears in subjects aged 50+ years. Most end-systolic AVA parameters are larger than those measured in end-diastole only in younger age decades. Dimensions of the AVA become tendentiously smaller with age in females, and a significant enlargement of AVA dimensions is present in case of 50+ years. Similar changes in AVA size could not be demonstrated in males. CONCLUSIONS: Age and gender-dependency of 3DSTE-derived AVA dimensions could be demonstrated in healthy adults.