Heart Disease: Sudden Cardiac Death (cont.)

Other risk factors 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.

Can Sudden Cardiac Death Be Prevented?

If you have any of the above listed risk factors for SCD, it is important that you speak with your doctor about possible steps to reduce your risk.

Keeping regular follow-up appointments with your doctor, making certain lifestyle changes, taking medications as prescribed, and having interventional procedures or surgery (as recommended) are ways you can reduce your risk.

Follow-up Care with Your Doctor: Your doctor will tell you how often you need to have follow-up visits. To prevent future episodes of sudden cardiac arrest, your doctor will want to perform diagnostic tests to determine what caused the cardiac event. Tests may include electrocardiogram (ECG or EKG), ambulatory monitoring, echocardiogram, cardiac catheterization and electrophysiology studies.

Ejection Fraction (EF): EF is a measurement of the percentage of blood pumped out of the heart with each beat. EF can be measured in your doctor's office during an echocardiogram (echo) or during other tests such as a MUGA (multiple gated acquisition) scan, cardiac catheterization, nuclear stress test, or magnetic resonance imaging (MRI) scan of the heart. The EF of a healthy heart ranges from 55 to 65 percent. Your EF can go up and down, based on your heart condition and the effectiveness of the therapies that have been prescribed. If you have heart disease, it is important to have your EF measured initially, and then as needed, based on changes in your condition. Ask your doctor how often you should have your EF checked.

Reducing your risk factors: If you have coronary artery disease -- and even if you do not -- there are certain lifestyle changes you can make to reduce your risk of sudden cardiac arrest.

These lifestyle changes include:

If you have questions or are unsure how make these changes, talk to your doctor. Patients and families should know the signs and symptoms of coronary artery disease and the steps to take if symptoms occur.

Medications: To help reduce the risk of sudden cardiac arrest, doctors may prescribe medications to people who have had heart attacks or who have heart failure or arrhythmias such as irregular heart rhythms. These medications may include ACE inhibitors, beta blockers, calcium channel blockers, and other antiarrhythmics. For patients with high cholesterol and coronary artery disease, statin medications may be prescribed.

If medication is prescribed, your doctor will give you more specific instructions. It is important that you know the names of your medications and any directions that you need to follow when taking them. If you have any questions, be sure to ask your doctor or pharmacist.

Implantable cardioverter-defibrillator (ICD): For people whose risk factors put them at great risk for sudden cardiac death, an ICD may be inserted as a preventive treatment. An ICD is a small machine similar to a pacemaker that is designed to correct arrhythmias. It detects and then corrects a fast heart rate. The ICD constantly monitors the heart rhythm. When it detects a very fast or slow heart rhythm, it delivers energy (a small, but powerful shock) to the heart muscle to cause the heart to beat in a normal rhythm again. The ICD also records the data of each abnormal heartbeat, which can be viewed by the doctor through a third part of the system kept at the hospital.


STAY INFORMED

Get the Latest health and medical information delivered direct to your inbox!