Sudden cardiac death (SCD) is the sudden, unexpected death caused by loss of heart function (sudden cardiac arrest). Sudden cardiac death is the largest cause of natural death in the United States, causing about 325,000 adult deaths in the United States each year. Sudden cardiac death is responsible for half of all heart disease deaths.

Sudden cardiac death occurs most frequently in adults in their mid-30s to mid-40s, and affects men twice as often as it does women. This condition is rare in children, affecting only 1 to 2 per 100,000 children each year.

Sudden cardiac arrest symptoms are immediate and drastic and include: sudden collapse, no pulse, no breathing, and loss of consciousness. Sometimes other signs and symptoms precede sudden cardiac arrest. These may include fatigue, fainting, blackouts, dizziness, chest pain, shortness of breath, weakness, profuse sweating, palpitations or vomiting. But sudden cardiac arrest often occurs with no warning.

Sudden cardiac arrest is not necessarily the same as a heart attack (myocardial infarction). Heart attacks occur when there is a blockage in one or more of the coronary arteries, preventing the heart from receiving enough oxygen-rich blood. If the oxygen in the blood cannot reach the heart muscle, the heart becomes damaged. In contrast, sudden cardiac arrest occurs when the electrical system to the heart malfunctions and suddenly becomes very irregular. The heart beats dangerously fast. The ventricles may flutter or quiver (ventricular fibrillation), and blood is not delivered to the body.

In the first few minutes, the greatest concern is that blood flow to the brain will be reduced so drastically that a person will lose consciousness. Death follows unless emergency treatment is begun immediately. Emergency treatment includes cardiopulmonary resuscitation (CPR) and defibrillation. CPR keeps enough oxygen in the lungs and gets it to the brain until the normal heart rhythm is restored with an electric shock to the chest (defibrillation). Portable defibrillators used by emergency personnel, or public access defibrillators (AEDs) may help save the person’s life. A patient who survives a sudden cardiac arrest, will most likely need an implantable defibrillator implanted in their chest to prevent this from happening again. Patients like this will need to followed up regularly by a heart rhythm specialists such as Dr. Hassan.

Studies have identified which patients are at risk for sudden cardiac arrest, which affords us an opportunity to identify these patients, assess their risk and protect them from these serious, possibly life-ending events before they happen. The largest population of patient at risk of sudden cardiac death are patients with weak heart muscle (left ventricular dysfunction) or cardiomyopathy and patients with previous heart attacks. If you have such condition, assessment by your cardiologist or our heart rhythm specialist is recommended.

Implantable Cardioverter Defibrillators (Heart Failure ICD or CRT-D)

Courtesy of St. Jude