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Health - Cardio Vascular Disease

defibrillatorSudden cardiac arrest isn't the same as a heart attack.

Someone in the prime of their life -- a professional sports star, teen athlete, marathon runner, or other seemingly healthy person -- isn't supposed to collapse and die from heart disease. But it occasionally happens, making sudden cardiac arrest front-page news.

The rare nature of sudden cardiac arrest among the young is precisely what makes it so attention-grabbing. According to the Cleveland Clinic, sudden cardiac death kills 1 in 100,000 to 1 in 300,000 athletes under age 35, more often males.

 

Among the most publicized cases: U.S. Olympic volleyball player Flo Hyman in 1986; college basketball player Hank Gathers in 1990; and professional basketball players Pete Maravich in 1988 and Reggie Lewis in 1993.
People wonder if anything could have been done to prevent such an event. They wonder who's at risk, and whether anyone can survive sudden cardiac arrest.

Fortunately, the answer is yes, says Christine E. Lawless, MD, MBA, a cardiologist and sports medicine doctor in Chicago. She is the co-chair of the American College of Cardiology's sports and exercise council, and a consulting cardiologist for Major League Soccer.

"We're trying to get folks to recognize that the person can come back from [cardiac] arrest if you get there within a minute," Lawless says. With immediate use of an automated external defibrillator, people have a chance to live.

What Is Sudden Cardiac Arrest?

When you hear about a young person dropping dead, you may think "heart attack." But sudden cardiac arrest (also referred to as sudden cardiac death) is different.

A heart attack stems from a circulation, or "plumbing," problem of the heart, according to the Sudden Cardiac Arrest Association. It happens when a sudden blockage in a coronary artery severely reduces or cuts off blood flow to the heart, damaging the heart muscle.

In contrast, a sudden cardiac arrest is due to an "electrical" problem in the heart. It happens when electrical signals that control the heart's pumping ability essentially short-circuit. Suddenly, the heart may beat dangerously fast, causing the heart's ventricles to quiver or flutter instead of pumping blood in a coordinated fashion. This rhythm disturbance, called ventricular fibrillation, "occurs in response to an underlying heart condition that may or may not have been detected," Lawless says.

Ventricular fibrillation disrupts the heart's pumping action, stopping blood flow to the rest of the body. A person in sudden cardiac arrest will collapse suddenly and lose consciousness, with no pulse or breathing.

Without immediate CPR or a shock from an automated defibrillator, the person usually dies within minutes -- that's why it's called "sudden cardiac death."

There is a connection between heart attack and sudden cardiac death, however. A heart attack can trigger an electrical malfunction that can lead to sudden cardiac arrest.

You probably know that high blood pressure, high cholesterol, diabetes, and other problems can lead to heart disease in older people. But you may not know about the rare heart disorders that can cause sudden cardiac arrest in young people.

"The underlying conditions in young people are very different from the underlying conditions in somebody who is 50 or 60 years old," Lawless says. "In the younger people, we're looking for inherited diseases of the myocardium [the heart's muscular tissue], of the electrical system, and then of course, congenital [heart] diseases."

The No. 1 culprit: hypertrophic cardiomyopathy (HCM), a disorder marked by abnormal thickening of the heart muscle. "Their heart is thick," Lawless says. "The inner layers of the heart maybe are not getting enough blood supply with exercise."

But remember, HCM is rare. It has been estimated to affect only 0.05% to 0.2% of the population.

Congenital abnormalities of the coronary arteries pose another risk for sudden cardiac arrest. The arteries may be positioned improperly -- or, as in basketball star Pete Maravich's case, a person may be born with only one coronary artery, instead of the usual two.

Other conditions that can trigger sudden cardiac arrest include an inherited electrical disorder of the heart called long QT syndrome; an inflammatory heart condition called acute myocarditis; and Marfan syndrome, which led to Flo Hyman's cardiac arrest.

Marfan syndrome is a genetic disorder of the connective tissue that can have fatal cardiovascular effects. People with Marfan syndrome "tend to be tall and lanky," Lawless says. They are at risk for tears in their blood vessels (such as the aorta). That risk rises with sudden increases in blood pressure, as may happen during intense sporting activity.

Some athletes die after being struck in the chest, a trauma called commotio cordis.

"When the chest is hit at the vulnerable period of the cardiac cycle, the heart goes into this terrible rhythm, the ventricular fibrillation," Lawless says. The window of time is miniscule, she says. "It's got to happen within forty-thousandths of a second."

Screening for Sudden Cardiac Arrest Risk

Sudden cardiac arrest occurs without previous symptoms in some cases.

But sometimes, there are red flags. For example, Reggie Lewis fainted during a basketball game a few months before his death.

The American Heart Association recommends a 12-step screening for high school and college athletes. It includes a careful family and medical history and a physical exam. The assessment asks about chest pain on exertion, unexplained fainting, a family history of premature death from heart disease, and other relevant issues. The physical exam includes a check for heart murmurs, pulses, blood pressure, and physical signs of Marfan syndrome.

But the assessment isn't applauded across the board, and how to best identify patients at risk remains debatable. Not all doctors use the assessment -- or even know that it exists -- and there are various issues involved.

For example, the causes of sudden cardiac arrest in athletes are rare. It's challenging to find a needle in a haystack in the best of circumstances.

Also, some athletes may be reluctant to report symptoms, especially if they think it could affect their playing time, rank, or scholarship chances.

There's another issue on top of that. "Probably the screening isn't done as diligently as it could be," says Vincent Mosesso, MD, FACEP, medical director of the Sudden Cardiac Arrest Association and a University of Pittsburgh professor of emergency medicine.

The AHA guidelines don't include a routine electrocardiogram (EKG) or echocardiogram (ultrasound evaluation of the heart). The use of these tests to screen athletes prior to participation is controversial and adds significant cost.

Opponents argue that there isn't enough evidence to support their effectiveness in screening, that these tests aren't cost-effective, and that they can lead to further unwarranted testing. They may also produce misleading results that bar many athletes unnecessarily. "The fact that they'll be left out is a very real problem," Lawless says.

But not everyone is waiting for these tests to get the official green light. In Maryland, Johns Hopkins offers a screening program for student athletes, aged 14 to 18. In addition to a medical questionnaire and physical exam, it includes an electrocardiogram to check the heart's electrical rhythm and to screen for long QT syndrome, and an echocardiogram to assess heart size and shape, pumping function, heart muscle thickness, and condition of the heart valves.

Despite the debate over screening techniques, it's important to catch problems early because treatment can reduce risk of sudden cardiac arrest. For example, young people who are at risk might need to avoid competitive sports, take beta blocker drugs to prevent the heart from beating too fast, or have surgery to implant a defibrillator that can shock their heart back into a normal electrical rhythm.

What to Do

Make sure your teen athlete gets the recommended AHA screening.

"You have to step up and insist on certain things at times," Mosesso says. "It's important for parents to tell the doctor that they actually want them to do the screening. A lot of times, my sense is that people just want someone to sign off on a form and just assume the kid's fine."

It might be a good idea to bring a copy of the AHA screening process to the visit.

Pay serious attention to any symptoms.

Heart problems that lead to cardiac arrest can produce signs, such as chest pain and blackouts (especially with exertion), fainting, palpitations or fluttering of the heart, becoming easily fatigued, weakness, dizziness, and shortness of breath.

Sports will increase stress on a vulnerable heart, so such symptoms tend to occur during or right after exercise.

Never ignore symptoms. Lawless recalls one high school athlete who went to the school nurse 16 times to complain of chest pain, but no one took his concerns seriously. "He then died from hypertrophic cardiomyopathy during sports," she says.

Don't forget: Young athletes don't always volunteer information when they feel unwell. "They're warriors. They want to stay in the game and show that they're 100% fit and that they can do the job," Lawless says.

But parents need to ask. "Be gentle with them and if something doesn't seem right to you -- if they get winded easily or they're clutching their chest -- make sure you have a conversation with them," Lawless says.

Even after a diagnosis, some athletes insist on playing. Lawless encountered one high school basketball player diagnosed with hypertrophic myocardiopathy after blacking out a couple of times on the court. Still, he wanted to play in college. "It takes a lot to convince people that when they have these conditions, they can't be playing these very high-intensity sports," Lawless says.

The same goes for adults. Any possible signs of heart trouble should not be ignored. Although symptoms with exertion in adults are unlikely to be due to these rare heart conditions, they may be due to coronary artery disease and should still be reported to your doctor so they can be evaluated.

Push for access to automated external defibrillators (AEDs).

These should be available at school and all sporting events and practices.

"There's absolutely no reason not to have them -- no good reason, in my mind," Lawless says.

AEDs are also available at some workplaces and public buildings. You don't have to be a doctor to use them -- they come with instructions. Once attached to the victim, they will diagnose and treat rhythm abnormalities automatically.
If you're intimidated by the idea of using an AED -- or want to be more prepared and also learn how to perform CPR -- the American Heart Association and Red Cross are two national groups that provide training.

People worry that defibrillators will require maintenance and increase liability, Lawless says, but the machines have been proven to save lives. "We know they work," Mosesso says.

By Katherine Kam