Sudden cardiac arrest may not always be so sudden, heart experts say.
A recent study has found that cardiac arrest symptoms in men can appear at least a month ahead of time. Signs can include chest pain, shortness of breath, dizziness, fainting or palpitations.
About 360,000 Americans suffer cardiac arrest each year. Fewer than 10 percent survive. It is responsible for half of all heart disease-related deaths.
Sudden cardiac arrest differs from a heart attack. Cardiac arrest occurs when electrical impulses in the heart become rapid or chaotic, causing the heart to stop beating. A heart attack happens when the blood supply to the heart is blocked.
The most common cause of cardiac arrest is an abnormal heart rhythm (arrhythmia) called ventricular fibrillation. This occurs when erratic electrical impulses cause your heart's lower chambers to quiver instead of pumping blood.
In the new study, researchers examined medical records of 800 men aged 35 to 65 who had an out-of-hospital cardiac arrest during a 12-year period in Portland, Oregon.
Of the 567 men who had an arrest, researchers determined 53 percent had symptoms beforehand. Those included chest pain, shortness of breath, dizziness, fainting and flu-like symptoms.
Eighty percent of the symptoms happened between four weeks and one hour before the actual arrest. Most of the men had heart disease, but only half had been diagnosed.