Signs of 'sudden' cardiac death may come weeks before: study

Signs of approaching "sudden" cardiac arrest, an electrical malfunction that stops the heart, usually appear at least a month ahead of time, according to a study of middle-age men in Portland, Oregon.

"We're looking at how to identify the Tim Russerts and Jim Gandolfinis - middle aged men in their 50s who drop dead and we don't have enough information why," said Sumeet Chugh, senior author of the study and associate director for genomic cardiology at the Cedars-Sinai Heart Institute in Los Angeles.

Some 360,000 out-of-hospital cardiac arrests occur each year in the United States, largely involving middle-aged men, with only 9.5 percent surviving, according to the American Heart Association.

Patients can survive if they are given cardiopulmonary resuscitation (CPR) immediately and their hearts are jolted back into normal rhythm with a defibrillator.

Earlier clinical trials have focused only on symptoms or warnings signs within an hour of such attacks. But Chugh's study set out to determine whether signs and symptoms occurred as much as a month before sudden cardiac arrests.

Researchers went back and examined medical records of men 35 to 65 years old after they had out-of-hospital attacks. In addition, paramedics reaching the scene of fatal attacks asked family members what signs and symptoms the patient may have had in preceding weeks.

What Is Sudden Cardiac Arrest?

Sudden cardiac arrest (SCA) is a condition in which the heart suddenly and unexpectedly stops beating. If this happens, blood stops flowing to the brain and other vital organs.

SCA usually causes death if it's not treated within minutes.
Overview

To understand SCA, it helps to understand how the heart works. The heart has an electrical system that controls the rate and rhythm of the heartbeat. Problems with the heart's electrical system can cause irregular heartbeats called arrhythmias (ah-RITH-me-ahs).

There are many types of arrhythmias. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm. Some arrhythmias can cause the heart to stop pumping blood to the body - these arrhythmias cause SCA.

SCA is not the same as a heart attack. A heart attack occurs if blood flow to part of the heart muscle is blocked. During a heart attack, the heart usually doesn't suddenly stop beating. SCA, however, may happen after or during recovery from a heart attack.

People who have heart disease are at higher risk for SCA. However, SCA can happen in people who appear healthy and have no known heart disease or other risk factors for SCA.
Outlook

Most people who have SCA die from it - often within minutes. Rapid treatment of SCA with a defibrillator can be lifesaving. A defibrillator is a device that sends an electric shock to the heart to try to restore its normal rhythm.