Sudden Cardiac Death

What Are the Risk Factors of Sudden Cardiac Arrest?

There are many risk factors that can increase a person’s risk of sudden cardiac arrest and sudden cardiac death, including the following:

• Previous heart attack with a large area of the heart damaged (75 percent of SCD cases are linked to a previous heart attack).
• A person’s risk of SCD is higher during the first six months after a heart attack.
• Coronary artery disease (80 percent of SCD cases are linked with this disease).
• Risk factors for coronary artery disease include smoking, family history of heart disease, and high cholesterol.

Other risk factors of sudden cardiac arrest include:

• Ejection fraction of less than 40 percent, combined with ventricular tachycardia.
• Prior episode of sudden cardiac arrest.
• Family history of sudden cardiac arrest or SCD.
• Personal or family history of certain abnormal heart rhythms, including long or short QT syndrome, Wolff-Parkinson-White syndrome, extremely low heart rates, or heart block.
• Ventricular tachycardia or ventricular fibrillation after a heart attack.
• History of congenital heart defects or blood vessel abnormalities.
• History of syncope (fainting episodes of unknown cause).
• Heart failure: a condition in which the heart’s pumping power is weaker than normal. Patients with heart failure are 6 to 9 times more likely than the general population to experience ventricular arrhythmias that can lead to sudden cardiac arrest.
• Dilated cardiomyopathy (cause of SCD in about 10 percent of the cases): a decrease in the heart’s ability to pump
• Hypertrophic cardiomyopathy: a thickened heart muscle that especially affects the ventricles.
• Significant changes in blood levels of potassium and magnesium (from using diuretics, for example), even if there is not underlying heart disease.
• Obesity.
• Diabetes.
• Recreational drug abuse.
• Taking drugs that are “pro-arrhythmic” may increase the risk for life-threatening arrhythmias