In a series of 88 human hearts, from individuals aged between 24 h and 94 yr (x= 61.09 +/- 21.96), the coronary arterial distribution of the right ventricle was studied using a modified Selvester's system of segmentation. Postmortem angiographies and microdissection techniques were used. The analysis of the six segments of the right ventricle shows that the three anterior segments, basal, mesial, and--less frequently--apical, present a type of irrigation that is practically constant and is dual. The postero-basal and postero-mesial segments are irrigated almost exclusively by the right coronary artery. In the remaining segments the vascularization was of mixed type, although a considerable degree of exclusive arterial perfusion was observed in the antero-apical segment. The segmental analysis allows us to conclude that although arterial vascularization of the right ventricle depends fundamentally on the right coronary artery, the anterior interventricular artery irrigates more than 20% of the right ventricular myocardium. Results from segmental analysis are compared with data from clinical and necropsic studies.