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The risk of sudden cardiac arrest (SCA) increases:
The major risk factor for SCA is ischemic heart disease. Most people who have SCA have some degree of ischemic heart disease; however, many people may not know that they have heart disease until SCA occurs. Usually their heart disease is “silent”—that is, it has no signs or symptoms. Because of this, doctors and nurses have not detected it.
Many people who have SCA also have silent, or undiagnosed, heart attacks before sudden cardiac arrest happens. These people have no clear signs of heart attack, and they don’t even realize that they’ve had one. Read more about risk factors for ischemic heart disease.
Other risk factors for SCA include: