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a throb or pulsation, as of the heart or of an artery.
apex beat the beat felt over the apex of the heart in the point of maximal impulse.
atrial beat an ectopic beat originating in an atrium.
1. a heartbeat resulting from the production of a ventricular complex by a supraventricular source following a period of atrioventricular dissociation.
dropped beat absence of one ventricular contraction.
echo beat reciprocal beat.
ectopic beat a heartbeat originating at some point other than the sinus node.
escape beat (escaped beat) heartbeats that follow an abnormally long pause.
forced beat an extrasystole produced by artificial stimulation of the heart.
fusion beat in electrocardiography, a P or QRS complex that results from the concurrent activation of the atria or the ventricles by two stimuli in the same chambers. An atrial fusion beat results when the sinus beat coincides with an atrial ectopic beat, when two atrial ectopic beats coincide, or when an atrial or sinus beat coincides with retrograde conduction from a junctional focus. A ventricular fusion beat results when a ventricular beat coincides with a sinus beat, a ventricular ectopic beat, or a junctional beat.
junctional beat an ectopic beat originating at the atrioventricular junction; see also junctional rhythm.
premature beat a cardiac event resulting from discharge by an atrial, junctional, or ventricular focus before the next expected sinus beat and at an interval from the last sinus beat that is shorter than its own intrinsic rhythm.
reciprocal beat a heartbeat resulting from an atrial or ventricular complex caused by a return of an impulse to its chamber of origin; called also echo beat.
sinus beat a heartbeat with sinus rhythm.
ventricular beat an ectopic beat originating in a ventricle.
a cardiac arrhythmia in which the impulse arising in the AV junction descends to and activates the ventricles on one intrajunctional pathway and simultaneously ascends toward the atria in parallel pathways; before reaching the atria, however, the impulse is reflected downward and again activates the ventricles, producing an echo or reciprocal beat; recognized in the electrocardiogram by the presence of an inverted P wave in lead aVF and usually II sandwiched between two ventricular complexes aberrantly, both of which may be normal or one of which may be conducted.