multifocal atrial tachycardia

tachycardia /tachy·car·dia/ (-kahr´de-ah) abnormally rapid heart rate.tachycar´diac

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atrial tachycardia  a rapid cardiac rate, usually 160–190 per minute, originating from an atrial locus.

atrioventricular (AV) junctional tachycardia , atrioventricular (AV) nodal tachycardia junctional t.

atrioventricular nodal reentrant tachycardia  that resulting from reentry in or around the atrioventricular node; it may be antidromic, in which conduction is anterograde over the accessory pathway and retrograde over the normal conduction pathway or orthodromic, in which conduction is anterograde over the normal conduction pathway and retrograde over the accessory pathway.

atrioventricular reciprocating tachycardia  (AVRT) a reentrant tachycardia in which the reentrant circuit contains both the normal conduction pathway and an accessory pathway as integral parts.

chaotic atrial tachycardia  that characterized by atrial rates of 100 to 130 beats per minute, markedly variable P wave morphology, and irregular P–P intervals, often leading to atrial fibrillation.

circus movement tachycardia  reentrant t.

ectopic tachycardia  rapid heart action in response to impulses arising outside the sinoatrial node.

junctional tachycardia  that arising in response to impulses originating in the atrioventricular junction, i.e., in the atrioventricular node, with a heart rate greater than 75 beats per minute.

multifocal atrial tachycardia  (MAT) chaotic atrial t.

nonparoxysmal junctional tachycardia  a junctional tachycardia of slow onset, with a heart rate of 70 to 130 beats per minute; due to enhanced automaticity of the atrioventricular junctional tissue, often secondary to disease or trauma.

paroxysmal tachycardia  rapid heart action that starts and stops abruptly.

paroxysmal supraventricular tachycardia  (PSVT) supraventricular tachycardia occurring in attacks of rapid onset and cessation, usually due to a reentrant circuit.

reciprocating tachycardia  a tachycardia due to a reentrant mechanism and characterized by a reciprocating rhythm.

reentrant tachycardia  any tachycardia characterized by a reentrant circuit.

sinus tachycardia  (ST) tachycardia originating in the sinus node; normal during exercise or anxiety but also associated with shock, hypotension, hypoxia, congestive heart failure, fever, and various high output states.

supraventricular tachycardia  (SVT) any regular tachycardia in which the point of stimulation is above the bundle branches; it may also include those arising from large reentrant circuits that encompass both atrial and ventricular sites.

ventricular tachycardia  an abnormally rapid ventricular rhythm with aberrant ventricular excitation, usually above 150 beats per minute, generated within the ventricle, and most often associated with atrioventricular dissociation.

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multifocal atrial tachycardia,

an atrial rhythm with a rate exceeding 100 beats/min caused by multifocal atrial activity and characterized by at least three different shapes of P′ waves on the electrocardiogram. The condition is often associated with chronic obstructive lung disease. Also called chaotic atrial tachycardia.

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multifocal atrial tachycardia

Atrial tachycardia Cardiology A rapid cardiac arrhythmia caused by stimuli to the heart from multiple locations within the atria, and characterized by irregularity, variable 'P' waves and–in adults–a poor prognosis; in MAT, multiple atrial foci “fire,” leading to tachycardia, often 100 to 180 beats/min, ↑ cardiac workload, but ↓ filling time, thus ↓ cardiac function; MAT is seen in 0.05-0.32% of the EKGs interpreted in general hospitals and is more common in the acutely ill–burns, sepsis, CHF, lung cancer, respiratory failure–COPD, PTE, CAD, elderly, recent surgery, hypoxia, theophylline or digitalis overdose, DM, bacterial infections, etc Treatment Magnesium, potassium, CCBs–eg, verapamil, β-adrenergic blockers–eg, metoprolol Prognosis 43% of Pts with MAT died during the hospital stay in which the arrhythmia was documented, but death was usually related to the underlying disease