Health Resources

MedlinePlus®

MerckSource received the 2006 WebAward for Outstanding Website Development from the Web Marketing Association at the annual WebAward competition.

MerckSource was honored at the Healthcare Internet Conference in Atlanta, receiving the 2006 Gold eHealthcare Leadership Award for best health/healthcare content.

MerckSource received the 2006 WWW site Award of Excellence from the Health Improvement Institute. This award honors excellence in health communications.

Resource Library

This information is provided by an independent source. Merck & Co., Inc. is not responsible for this content. Please discuss any and all treatment options with your healthcare professional. The manufacturer of a product generally has the most complete information about that product.

Return to Main Index

>> How to Use

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

defibrillation (de-fib″rĭ-la�shәn) termination of atrial or ventricular fibrillation, usually by electric shock. Defibrillation by precordial shock is done by delivering a nonsynchronized direct current to the myocardium; this is an emergency procedure, used to stop life-threatening ventricular arrhythmia. The electric shock is delivered either by placing metal paddles on the chest (closed defibrillation) or by applying paddles directly to the heart muscle, as in cardiac surgery. The high-voltage electrical current delivered during precordial shock causes complete depolarization of the heart muscle, disrupting all the electrical circuits that are activating it and causing ventricular fibrillation. That allows the heart's natural pacemaker to regain control and regulation of the heart rate and rhythm.

Search MerckSource

Sign In

Health Resources

MedlinePlus®

Resource Library