A junctional escape beat is a delayed heartbeat originating not from the atrium but from an ectopic focus somewhere in the AV junction. It occurs when the rate of depolarization of the sinoatrial node falls below the rate of the atrioventricular node. This dysrhythmia also may occur when the electrical impulses from the SA node fail to reach the AV node because of SA or AV block. It is a protective mechanism for the heart, to compensate for the SA node no longer handling the pacemaking activity, and is one of a series of backup sites that can take over pacemaker function when the SA node fails to do so.
Read more about Junctional Escape Beat: Etiology, ECG Characteristics, Significance
Famous quotes containing the words escape and/or beat:
“We know how powerful our mother was when we were little, but is our wife that powerful to us now? Must we relive our great deed of escape from Mama with every other woman in our life?”
—Frank Pittman (20th century)
“It is the fixed that horrifies us, the fixed that assails us with the tremendous force of mindlessness. The fixed is a Mason jar, and we can’t beat it open. ...The fixed is a world without fire--dead flint, dead tinder, and nowhere a spark. It is motion without direction, force without power, the aimless procession of caterpillars round the rim of a vase, and I hate it because at any moment I myself might step to that charmed and glistening thread.”
—Annie Dillard (b. 1945)