1. A medical image processing apparatus, comprising: a medical image data obtaining unit for obtaining medical image data containing an image of a heart; and a region extraction processing unit for extracting a left ventricular region of the heart in the medical image data obtained by the medical image data obtaining unit, and, based on an extraction result of the left ventricular region, performing region extraction processing for extracting at least one of a right ventricular region, a left atrium region, and a right atrium region of the heart.