Multifocal atrial tachycardia
Multifocal atrial tachycardia is an irregular atrial tachyarrhythmia defined by at least three distinct P-wave morphologies and varying PR intervals, arising from multiple atrial foci and strongly associated with severe pulmonary disease such as COPD exacerbation. Diagnosis is by ECG, and treatment centers on correcting the underlying illness, with a non-dihydropyridine calcium channel blocker for rate control.
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What this article covers
- Overview
Definition: multifocal atrial tachycardia (MAT) is an irregular supraventricular tachyarrhythmia originating from multiple atrial foci, defined by at least three distinct P-wave morphologies with…
- Epidemiology
Occurs mainly in older, acutely ill patients with pulmonary disease.
- Risk factors
COPD and other severe pulmonary disease with hypoxemia.
- Pathophysiology
Multiple ectopic atrial foci: enhanced automaticity and triggered activity in several atrial sites, promoted by atrial stretch, hypoxemia, catecholamines, and electrolyte derangement.
- Clinical features
Symptoms of the underlying illness dominate: dyspnea and hypoxemia of a COPD exacerbation.
- Differential diagnosis
Atrial fibrillation: irregular but without organized discrete P waves (atrial fibrillation).
- Diagnosis
Establish with an ECG showing at least three distinct P-wave morphologies with varying intervals at a rate above 100: the diagnostic basis is a 12-lead ECG demonstrating an irregular atrial…
- Management
First, treat the underlying illness: optimize oxygenation and treat the COPD exacerbation, sepsis, or heart failure driving the arrhythmia.
- Complications
Reflects severe underlying illness with attendant high mortality.
- Prognosis
Driven by the underlying disease: prognosis largely reflects the severity of the pulmonary or systemic illness.
- Prevention
Optimize chronic pulmonary disease and prevent exacerbations.
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