Sudden Cardiac Death

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What is Sudden Cardiac Death?

Sudden Cardiac Death (SCD) is a swift and unexpected death caused by a heart condition or mechanism, which may or may not be obvious. SCD varies in its range of definition. Usually, though, it applies to a situation where the person, who was thought to be free of heart disease, or only had a "mild" heart disease, suddenly died.

What causes these sudden deaths?

In the age range between 40 and older, the vast majority is due to coronary artery disease (heart "attacks"). In 20% (one out of five) of those who develop symptoms of coronary artery disease, and even among those with advanced coronary artery disease, the first symptom of the disease is sudden death. In those younger than forty years old, including teenagers, sudden death from "no apparent reason" is usually due to fatal ventricular arrythmia (heart irregularity), which could be brought on by electrolyte imbalance and other factors, and in some cases, to totally unknown cause.

Can illegal drugs like Cocaine cause sudden death?

Yes, particularly Cocaine. Other "recreational" drugs could also lead to sudden death, many by causing deadly heart irregularity.

What is a "Widow-Maker" coronary artery disease?

As the name implies, this particular condition results in sudden deaths among men, leaving their wives widows. This is usually due to a severe blockage of the left main coronary artery. This left main coronary artery has two branches, one supplying blood to the left ventricle and the septum (inner dividing wall) of the heart, and one supplying blood to the muscles of the back of the heart. If the left main coronary artery is blocked, all the left ventricular muscles are deprived of blood and suffer a massive acute heart attack, followed by sudden death. Even a single coronary blockage, if severe enough, could be dangerous, and deadly, depending on the portion of the heart that suffers.

Could Mitral Valve Prolapse cause sudden death?

Yes, but, fortunately, very rarely. Mitral Valve Prolapse is a condition where this valve on the left side of the heart (between the left upper and left lower chamber) is kind of "limp" and "weak" resulting in a slightly or moderately leaking Mitral Valve. This condition is generally benign and does not require surgery. Medications and some lifestyle changes are the therapies of choice.

What are the usual symptoms prior to SCD?

Interviews with family of the victims usually reveal some angina (chest discomfort or tightness), or heart irregularity, and/or shortness of breath, and worsening of the symptoms over a few days or a few hours before sudden collapse and death in 75% of these people. Some of these symptoms may even be self-diagnosed by the victims as indigestion, fatigue, muscle pains, or depression. Self-denial (of symptoms) makes this condition treacherous. Anyone with any of these symptoms should consult their physicians without delay.

Does a normal EKG preclude SCD?

No, a plain resting EKG that is reported as normal does not eliminate the possibility of Sudden Cardiac Death, especially among patients with coronary artery disease, whether previously diagnosed or still undetected. This is the reason why a Stress EKG, preferably with Thallium, or Stress Echocardiography, are recommended to find out how the heart would behave under stress. These are more accurate and significant tests compared to a simple resting EKG. A plain EKG is only helpful if it shows abnormal findings. If it is "normal," it does not have an accurate diagnostic value, and thus, cannot be depended upon for prognostication.

Can a Pacemaker prevent SCD?

Not really, if the coronary artery disease that is causing the problem is not treated. The Pacemaker only stimulates the heart muscles to beat, with small electrical jolts that the person does not even feel. If the heart muscles are not getting enough blood because the coronary arteries are blocked, these muscles will not beat well at all, in spite of the pacemaker stimulation.

How about Automatic Defibrillators?

Automatic Implantable Cardiac Defibrillator (AICD) is a self-contained computerized defibrillator (one that automatically shocks the heart when it develops ventricular fibrillation or when cardiac arrest occurs) combined with a pacemaker feature that paces the heart to a more regular and normal beat. This unit is slightly smaller than a hockey pock, implanted under the skin in the upper chest, much like a regular cardiac pacemaker. AICDs are recommended for people who have had cardiac arrests in the past or those who are candidates for Sudden Cardiac Death.

When a patient is hugging someone and the defibrillator sends a jolt, does the other person also feel the "electrical shock"?

No, not at all. Only the patient feels the jolt, which results in a sudden reflex body twitch. The current is so small it is not conducted to the other person. The patient, following this defibrillator shock, temporarily becomes confused, weak and tired. These implantable defibrillators have saved thousands of lives.

Can Sudden Cardiac Deaths be prevented?

Since most of these SCDs are due to coronary artery disease, primary prevention should be aimed at warding off coronary artery disease before it develops, like avoidance of cigarette smoking, obesity, sedentary lifestyle; and the management of high blood pressure, diabetes, and elevated cholesterol, if these are present. Secondary prevention is by early diagnosis and treatment of coronary artery disease, and any medically significant arrythmias present. And where indicated, AICD implantation should be considered.

Do these pacemakers and defibrillators trigger airport metal sensor to alarm?

Yes. This is one of the reasons why each patient with a cardiac pacemaker or a defibrillator is provided a medical identification card from the manufacturer of the device. A doctor's certification will also be acceptable to the airport security staff. Patients with any of these devices, who do not have any restrictions from their cardiologist, may travel by air safely.

©2003Raoul R. Diez, M.A.O.D.