fusion beat(redirected from summation beat)
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 beat triggered by more than a single electrical impulse, when the wave fronts coincide to act together on a single final pathway of activity; in the electrocardiogram, the atrial or ventricular complex when either atria or ventricles are activated jointly by two simultaneous or nearly simultaneous invading impulses.
fusion beatCardiology The superimposing of an ectopic beat on a paced natural sinoatrial node beat; an FB is usually narrower than a paced impulse and has various morphologies that reflect the relative contributions of the impulse to the venticular depolarization. See Pseudofusion beat.
fu·sion beat(fyū'zhŭn bēt)
A beat triggered by more than a single electrical impulse, when the wave fronts coincide to act together on a single final pathway of activity; in the electrocardiogram, the atrial or ventricular complex when either atria or ventricles are activated jointly by two simultaneous or nearly simultaneous invading impulses.