A Large Whale Heart

Abstract

A large whale heart weighing 256 pounds (116 Kg.) was dissected. The coronary arteries had extremely large right and left marginal branches, which supplied the major lateral mass of the right and left ventricles. The venous system was similar to other mammals. Crude ventricular volume and cardiac output was calculated to be 453 L. per minute based on a rate of 10 per minute. The size of the cardiac muscle fiber was similar to the human myocardium except in a fetal whale heart (wt. 1,600 Gm.) in which very small fibers were found. The aorta was found to be 20 cm. in diameter and the wall to consist of very large interwoven bundles of elastie tissue and fibrous tissue apparently devoid of muscle. There was no evidence of arteriosclerosis. Comparative estimated cardiac output/body weight ratios and heart weight/body weight ratios were made between the whale and the human.