Cardiologists in the Keck School of Medicine of USC are applauding the federal government’s expanded Medicare coverage of implantable cardioverter defibrillators (ICDs), noting the decision will likely save thousands of lives a year.

More Americans die from coronary heart disease than from any other cause. Cardiologists say that cardiac arrest – also called sudden cardiac death – accounts for about half of those coronary heart disease deaths.

When implanted in a patient’s chest, an ICD can interrupt cardiac arrest by monitoring the heart’s rhythm and delivering an electrical shock when a life-threatening arrhythmia is detected.

“Sudden cardiac death causes about a thousand deaths in this country every single day,” said cardiac electrophysiologist Leslie A. Saxon, professor of medicine in the Keck School.

“Research shows that 95 percent of people who experience cardiac arrest die, often before they can even reach an emergency room. But with an implantable defibrillator, sudden death could actually be prevented in 98 percent of cases,” Saxon said.

Saxon helped conduct much of the research showing that defibrillators and similar cardiac devices can save lives.

Many patients with heart trouble who have needed the defibrillators have been unable to afford them, until now. Medicare’s expanded coverage will allow patients who have never had a heart attack – but who have a serious heart condition – to benefit from the ICDs.

Medicare is the federal health insurance program for the elderly and disabled.

Now, said Saxon, who serves in the division of cardiovascular medicine as director of electrophysiology at USC University Hospital, Americans must educate themselves about their heart health, so that if they develop a condition that puts them at risk for sudden cardiac death, they may receive treatment – and an ICD, if appropriate – in time potentially to save their lives.

Saxon explained that with every heartbeat, oxygen-rich blood is squeezed or ejected out of the heart’s left ventricle, the biggest and most muscular of the heart’s four chambers.

Using tests, such as an echocardiogram, doctors can see how well the left ventricle works by taking a measure called an ejection fraction, which is the percentage of blood squeezed out of the left ventricle with each heartbeat. An ejection fraction of 50 percent means the ventricle spurts out half its volume each time it contracts.

Healthy ejection fractions are 50 percent or higher; lower ejection fractions can mean cardiomyopathy – a disease of the heart muscle that saps the muscle’s strength.

Cardiomyopathy is a major cause of sudden cardiac death. Under the proposed Medicare decision, the insurance program would cover implantation of an ICD in most patients with cardiomyopathy and an ejection fraction of 30 percent or less.

“Everyone should know their ejection fraction, just like they know their cholesterol level, blood pressure and other measures of cardiovascular health,” Saxon said.

Victims of sudden cardiac arrest average about 60 years old, and many are active and seem healthy until the moment the heart gives out.

Saxon noted that cardiologists recognize a list of factors that point to a high risk for sudden cardiac death. She encourages people to watch for the following factors:

• A history of heart attack or heart muscle damage;
• shortness of breath;
• fatigue;
• ankle swelling; and
• exertional intolerance (having a hard time with exercise or physical effort such as climbing stairs or carrying a load.)

“It’s important not only to recognize these factors in yourself, but also in your family and loved ones,” Saxon said.

“If heart disease is diagnosed in time, and appropriately treated through medication and devices, if needed, many of the more than 340,000 lives lost each year to sudden cardiac death could be saved.”

For more information on ICDs or eligibility requirements, visit http://www.usc.edu/cardiacep or call 1-800-USC-CARE.