The Heart of a Champion

There was an article in Monday's New York Times about ongoing research on the size of elite athletes' hearts. There has been concern in recent years about the possible stress that an enlarged heart places on the rest of the body. Three U. S. Olympic rowers are among the athletes participating in a study to determine whether a huge heart is dangerous or a normal adaption to strenuous exercise.

Doctors and scientists have known for some time that athletes like marathon runners and Tour de France cyclists have enlarged hearts and many have wondered whether the phenomenon can contribute to sudden death. Now it seems that their fears are unfounded. According to Dr. Paul Thompson, a cardiologist at Hartford Hospital, as long as a heart is healthy, there is never a point at which it is too big. Dr. Benjamin Levine, a cardiologist at the University of Texas Southwestern Medical Center in Dallas, notes that a heart can grow or shrink by a third depending on the demands being placed on it.

Nonetheless it was a surprise to cardiologists Dr. Malissa Wood and Dr. Aaron Baggish, both of Mass. General, when they began to study the hearts of three Olympic rowers. They took their first readings in December and were amazed at the sizes of the the rowers' hearts. "Their hearts were incredible, " Wood said. "Their masses were some of the biggest we have ever seen." And when they checked those same hearts three months later, they were even more amazed to discover they had grown even larger.

These large hearts actually mimic those of athletes who have hypertrophic cardiomyopathy, a condition that effects 1 in 1500 people and is the leading cause of sudden death in athletes. But there is an important difference, according to Wood. The key in determining a healthy large heart from one that is not as healthy is not its size but its functions, specifically those of high velocity pumping and super powerful suctioning of blood back into the heart. In particular, an ill heart does not have the same suctioning capabilities.

All of which reminded me of Secretariat's heart, which upon his death was determined to be almost twice the average size and a third larger than any equine heart Dr. Thomas Swerczek (the doctor who performed the necropsy) had ever seen. And yet, according to Swerczek, "It wasn't pathologically enlarged. All the chambers and the valves were normal. It was just larger."

Romantics like to attribute "a big heart" to superior athletic performance but in this case, science has demonstrated that a big heart is often the by product of elite training.

So the question remains, did Secretariat's heart become that big over time or was it always oversize? And in the end, did it contribute to his accomplishments or result from them?

Leave me a comment and let me know what you think.