Sudden cardiac arrests might not be sudden in most cases, a US study said Tuesday.

More than half of the middle-age men who had a sudden cardiac arrest had possible warning signs up to a month before, according to the study presented at the American Heart Association's Scientific Sessions 2013 in Dallas.

Cardiac arrest occurs when the heart abruptly stops pumping. Patients can sometimes survive if they receive cardiopulmonary resuscitation immediately and a defibrillator is used quickly to shock the heart into a normal rhythm.

About 360,000 out-of-hospital cardiac arrests are reported each year in the United States, according to the American Heart Association. Only 9.5 percent of people who suffer a cardiac arrest outside the hospital survive.

"By the time rescuers get there, it's much too late," Eloi Marijon, study lead author and a visiting scientist at Cedars- Sinai Heart Institute in Los Angeles, said in a statement.

The researchers gathered information about the symptoms and health history of 567 men 35 to 65 years old who had out-of- hospital cardiac arrests between 2002 and 2012 and found 53 percent had symptoms beforehand.

Of those with symptoms, 56 percent had chest pain, 13 percent had shortness of breath and 4 percent had dizziness, fainting or palpitations, the researchers said.

Marijon said almost 80 percent of the symptoms occurred between four weeks and one hour before the sudden cardiac arrest.

"The lesson is, if you have these kinds of symptoms, please don 't blow them off," Sumeet Chugh, senior author and associate director for genomic cardiology at the Cedars-Sinai Heart Institute, said. "Go see your healthcare provider. Don't waste time."

The researchers said now they are conducting similar work in women.