Fight Medicine: Hardy’s Heart Condition

---

Former Ultimate Fighting Championship welterweight title contender Dan Hardy last week announced his withdrawal from a UFC on Fox 7 bout with Matt Brown on April 20 at the HP Pavilion in San Jose, Calif. While most fighters point to injury when announcing such exits, Hardy’s story was a little different. Pre-fight tests revealed he has a syndrome called Wolf-Parkinson-White, which is an abnormality in the conduction system of the heart.

The heart’s job is to pump blood to the lungs to get oxygen, receive back that blood, pump it to the rest of the body and then re-collect it to start the process again. The heart has four chambers, each of which is responsible for one of the four tasks mentioned. The heartbeat you can hear with a stethoscope is actually the sound of valves between each of these chambers closing after the blood has flowed to its next destination. The coordination of each of these chambers requires a finely tuned electrical conduction system.

The heart muscle cells are triggered to contract by a wave of electricity that starts at the top of the heart -- the SA node -- and spreads across the top two chambers, the left and right atrium, causing them to squeeze blood towards the bottom of the heart. The electrical signal then triggers another node -- the AV node -- above the two larger chambers, the left and right ventricles. From the AV node, a bundle of electrical fibers travels to the two large ventricle chambers, which causes them to contract, squeezing the blood to the lungs and the rest of the body; the right goes to the lungs, the left to the rest of the body.

In people with Wolf-Parkinson-White syndrome, there is an extra pathway that bypasses the AV node and goes straight from the left and right atrium to the left and right ventricles. This alters the coordination of the heart and can cause the ventricles to squeeze before they have had a chance to fill completely with blood. As a result, less blood gets pumped out of the heart for each heartbeat. Many of those afflicted remain without symptoms, but on occasion, some may experience dizziness, fainting or heart palpitations. In severe cases, the whole heart loses its coordination and sudden death can occur.

The diagnosis is usually made by an electrical heart monitor called an electrocardiogram or EKG. We have all seen the spiked pattern on a heart monitor in the movies before it flatlines and someone dies. That pattern represents very specific electrical discharges from different parts of the heart. When the EKG pattern is disrupted, it means something is wrong with the heart’s electrical activity. In the case of Wolf-Parkinson-White syndrome, the abnormality is called a “delta” wave because it looks like the Greek letter of the same name. Patients with the condition must be careful with what drugs they take because they can worsen the electrical abnormalities.

A fighter -- or any other athlete for that matter -- who has been diagnosed with Wolf-Parkinson-White syndrome should not compete until he or she is cleared by a cardiologist. The cardiologist may order a stress test, which is a way of seeing how one’s heart functions during exercise since the coordination may get out of control as it beats faster. This test can be done on a treadmill with an EKG, or medication can be given to speed up the heart.

If a cardiologist thinks the abnormality is under control, then no medication or intervention is necessary. However, if the stress test shows that the heart becomes even more out of control with exercise, he may order medication. The most definitive treatment is a procedure known as radiofrequency ablation, where specialized instruments are used to burn away the abnormal heart pathway, helping to restore the coordination of the heart.

Hardy appears to have undergone these tests, but the California State Athletic Commission is playing it safe and keeping the 30-year-old off the UFC on Fox 7 lineup and out of action for now. After all, bone and tendon injuries heal, but a heart that stops beating may never start again.

Follow Jon “The Fight Doc” Gelber on Twitter at @FightMedicine or visit FightMedicine.net.