The Olmec Heart Effigy Revisited: A Highly Accurate, Ancient Depiction of the Human Heart

THE OLMEC HEART EFFIGY REVISITED: A HIGHLY ACCURATE, ANCIENT DEPICTION OF THE HUMAN HEART COLIN K. PHOON* As a pediatric cardiologist with a special interest in cardiac morphology and cardiac imaging, I was fascinated by Dr. Gordon Bendersky's essay describing the "Olmec heart effigy" receptacle, first identified as a representation of the human heart by The Art Museum at Princeton University [I]. I found Bendersky's argument compelling and of great historical interest. However, I believe that the Olmec artisan who fashioned the receptacle deserves even more credit for anatomic accuracy than is given by Bendersky 's interpretation. Bendersky 's Argument Bendersky's argument that the Olmec receptacle represents a human heart is reasonably sound. I do agree that the receptacle (Fig. 1) looks like a "human figure with a heart (and great blood vessels) of exaggerated size," the obvious first step in his argument [I]. I also agree that it is rotated so that the postulated right and left ventricles of the heart are properly right and left, respectively, instead of rightward/anterior and leftward/posterior, which is how the chambers are normally situated in the chest. The Olmec heart's supero-inferior (top-bottom, so to speak) axis is also rotated, so that the apex ("bottom") points straight down, rather than down and leftward along an approximate 4 o'clock axis (Fig. 2). Bendersky argues that the groove running vertically down the midline of the receptacle represents the interventricular sulcus, and that it runs to the base of the great blood vessels. The heart is therefore represented as *Division of Pediatric Cardiology, Pediatric Echocardiography Laboratory, New York University Medical Center, 530 First Avenue, New York, NY 10016.© 1998 by The University of Chicago. All rights reserved. 0031-5982/98/4104-1069$01.00 540 Colin K Phoon ¦ Olmec Heart Effigy Revisited Pulmonary artery Aorta Superior vena cava "Enigmatic forms" Interventricular sulcus FiG. 1.—Diagram of the Olmec heart-shaped receptacle, with Bendersky's interpretation of the structures. having two chambers (two ventricles). Thus, he argues, the blood vessel arising to the right of the head (that is, to the right of the sulcus) and coursing rightward must be the pulmonary artery; the blood vessel arising immediately to the left of the head (that is, immediately to the left of the sulcus) and coursing leftward must be the aorta. This argument to define the great arteries by their locations relative to the interventricular sulcus is reasonable. The leftmost blood vessel is labeled the superior vena cava. In this interpretation of the receptacle, Bendersky does admit that the plane of the blood vessels, as well as the relative sizes of the pulmonary artery and aorta, are not quite anatomically accurate. Key Flaw in Bendersky 's Argument What Bendersky does not address is why the superior vena cava should be left-sided at all. The failure to ask this key question leads to quite a different interpretation of the Olmec receptacle's anatomy. In the normal heart, the superior vena cava is, in any plane ofview, a right-sided structure; it runs along an almost vertical direction down into the right side of the heart, into the right atrium (Fig. 2). No amount of exaggeration or distortion would produce a left-sided superior vena cava, short ofrotating a heart completely around with front facing back. Congenital heart malformations do occur in which a left superior vena cava is present together with a right superior vena cava, but an isolated left superior vena cava (in the absence of a right-sided one) is very rare. A left superior vena cava almost always runs into the coronary sinus, which is a posterior structure, around the back ofthe heart; therefore, a left superior vena cava is relatively inconspicPerspeclives in Biology and Medicine, 41, 4 ¦ Summer 1998 | 541 Aorta \ ^