Definition: A supraventricular arrhythmia characterized by uncoordinated atrial myocardium activation due to multiple reentry circuits with consequent deterioration of atrial mechanical function. Instead of intermittently contracting, the atria quiver continuously in a chaotic pattern, causing a totally irregular, often tachycardia ventricular rate. On the ECG it is described by the replacement of consistent P waves by rapid oscillations or fibrillatory waves that vary in size, shape, and timing, associated with an irregular, frequently rapid ventricular response when atrioventricular conduction is intact. (NCI)
Synonyms (terms occurring on more labels are shown first): atrial fibrillation, AFIB, fibrillation atrial, atrial fibrillations, atrial fibrilla tion, atrialfibrillation
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