This picture shows an ECG (electrocardiogram, EKG) of a person with
an abnormal rhythm (arrhythmia) called an atrioventricular (AV)
block. P waves show that the top of the heart received electrical
activity. Each P wave is usually followed by the tall (QRS) waves.
QRS waves reflect the electrical activity that causes the heart to
contract. When a P wave is present and not followed by a QRS wave
(and heart contraction), there is an atrioventricular block, and a
very slow pulse (bradycardia).
Review Date: 05/23/2010
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of
General Medicine, Department of Medicine, University of Washington
School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical
Director, A.D.A.M., Inc.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)
