Sudden Cardiac Death (SCD) - Detection

Dateline: 11/01/98

Have you read my previous article on SCD syndrome - Sudden Cardiac Death - Causes and Mechanisms ?

How to identify SCD ?

The night before she died, Florence Griffith Joyner felt "a little tired" but showed no outward signs of illness, her former coach said. Asked about a seizure Griffith Joyner had in St. Louis two years ago, Kersee said she was hospitalized overnight but doctors could find nothing wrong and released her.

How then could anyone have known she was at risk for SCD ?

Flo Jo's case only highlights the fact that SCD is almost impossible to predict with any degree of certainty. Prodromal symptoms are so non-specific that they are of no value in forecasting a serious event. In fact, in many cases they may result in patient contact with the medical system in the weeks or months preceeding SCD.

The onset of the terminal event - the period of one hour or less between onset of acute changes in cardiovascular status and the actual cardiac arrest - is one area about which there is limited information. This limited data available reveals an increase in the heart electrical rhythm disturbances - ventricular ectopy.

The cardiac arrest itself is a highly recognizable, indeed dramatic event. There is an abrupt loss of consciousness, caused by a reduction in blood flow to the brain. Uniformly, death will ensue unless immediate action is taken.

Do all victims succumb to cardiac arrest ?

Certainly not. However, the potential for successful resuscitation depends upon

• the setting in which the cardiac arrest occurs
• the mechanism of the cardiac arrest - rhythm disturbance, mechanical failure etc.
• the underlying clinical status of the victim

The progression to the next irreversible stage of biological death is directly related to the intensity of the efforts to save the patient. Without intervention, irreversible brain damage occurs within 4 to 6 minutes ! Attendent upon this knowledge, then, is the need to make an important decision in victims seen late after the cardiac arrest - to resuscitate or not.

Recommended Reading :

Sudden Cardiac Death in the Athlete
by N. A. Mark Estes(Editor), et al / Hardcover / Published 1998
Buy it from Amazon.com. Visit the Heart Bookstore for more titles on SCD.

To learn more about Sudden Cardiac Death syndrome, read the next article in this series.