The quantitative anatomy and morphology of hypoplastic ventricles were studied in 28 afflicted hearts (15 with left ventricular hypoplasia, 13 with right ventricular hypoplasia). The control comprised 10 normal heart specimens. All the 38 specimens were studied morphometrically; this was complemented with angiocardiometry and ventricular volume estimations in diagnosing right ventricular hypoplasia. Based on the study results, the morphometric criteria of ventricular hypoplasias and their variant forms were established. The linear characteristics were found to be informative enough both in hypoplasia diagnosis and in its degree assessment. To choose a therapeutic method, two degrees of right ventricular hypoplasia were distinguished. Radical correction aimed at eliminating concomitant conditions was found to be feasible and performed in 27 patients with moderate right ventricular hypoplasia.