Undetected heart conditions stop athletes with no warning

By Stu Durando, St. Louis Post-Dispatch, March 10, 2007

Holly Morrell was a child when her cousin Kyle collapsed and died while walking home from school in 1975. One year later, another cousin, Mitchell, suffered the same fate after climbing a fence.

In all, six of Morrell''s relatives in California have died from hypertrophic cardiomyopathy (HCM), a condition in which the heart has extra muscle that can cause it to function abnormally and prompt sudden death.

Doctors have known for years that when a seemingly healthy person dies suddenly, as did former Missouri running back Damien Nash on Feb. 24, the most common cause is an undetected heart condition. Among those conditions is HCM, which Dr. Keith Mankowitz, director of the Hypertrophic Cardiomyopathy Clinic at Barnes-Jewish Hospital, says is responsible for 36 percent of sudden deaths among athletes younger than 35.

The cause of Nash''s death is still under investigation, and other conditions, such as coronary artery anomalies, which killed retired basketball star Pete Maravich, and Marfan syndrome, which claimed volleyball star Flo Hyman, can be responsible.

But HCM, which is estimated to be present in 1 in 500 people, according to the New England Journal of Medicine, has been tied to the deaths of many high-profile athletes, including basketball players Hank Gathers and Reggie Lewis, figure skater Sergei Grinkov and several international soccer stars.

"It''s not necessarily the athlete, but anyone who exerts themselves, especially in sudden bursts, who can put themselves at increased risk of sudden death," Mankowitz said. "It''s the exertion of sudden sprinting or bursts of physical exertion that provokes and brings out the worst in underlying heart conditions."

Nash''s brother, Darris, had a heart muscle condition called dilated cardiomyopathy (DCM) and underwent a heart transplant last year. DCM causes the heart to become enlarged and to pump less strongly.

Dr. Gregory Ewald, the cardiologist who treats Darris Nash, said Damien Nash likely would have shown symptoms before his death if he also had DCM. And although DCM can be genetic, Ewald said it would be unusual for the gene that causes the disorder to cause HCM in a family member.

"Usually you have the same type of clusters in a family and a gene that is responsible," he said. "For the most part, family members are going to have the same form of cardiomyopathy. Darris'' cardiomyopathy is not necessarily genetic in nature."

Morrell, 40, was diagnosed with HCM in 2002 and now has a defibrillator imbedded in her chest. In addition to her cousins, she has lost her father and a grandmother, aunt and uncle to the disease. She educates athletes and the general public about the disease through A Heart for Sports, an organization she formed to screen high school and college athletes.

The death of NFL player Thomas Herrion in 2005 led her to believe that the number of HCM-related deaths might be higher than reported. Herrion''s autopsy did not show he had HCM until four top cardiologists studied the report as part of an ESPN investigation and reached that conclusion.

The second-most common cause of cardiovascular sudden death is coronary artery anomalies, which Mankowitz said are best detected through a CAT scan or MRI of the coronary arteries.

Sudden deaths have been reported in many sports but are most common in basketball and football in the United States and in soccer in Europe. And men are nine times more likely to die than women.

"The numbers should be getting better because we have better technology," said Dr. Ben Wedro of the Gundersen Lutheran Medical Center in La Crosse, Wis. "There are more athletic trainers at events."

But sometimes, such as in Nash''s case, a person is not stricken at an athletic event. Medical treatment must be administered within three to five minutes for the best outcome, so a person''s location can determine the chances of survival.

Mankowitz said standard physicals detect HCM in few cases. Patients can increase the likelihood of discovering the disorder by having their doctor listen to their heart while they stand and squat, he said.

The next step is to get an EKG, which is even more accurate. He said the "gold standard" for diagnosing HCM is an echocardiogram.

"Most patients who die have no symptoms," Mankowitz said. "It''s very difficult to pick it up on a basic physical exam. If kids have chest pains, passing out or shortness of breath, we look for this condition specifically."

Once diagnosed, he said, a person with HCM should not participate in activities that involve "burst exertion" such as soccer, football and basketball. Medications exist for HCM, but they do not protect against sudden death.