Which condition is a known risk factor for multifocal atrial tachycardia (MAT)?

Which condition is a known risk factor for multifocal atrial tachycardia (MAT)?

• A. COPD
• B. Hypertension
• C. Hyperthyroidism
• D. Coronary artery disease

Answer: (A)

MAT arises most often in the setting of significant lung disease, where hypoxemia and atrial irritability create multiple competing atrial pacemaker sites. Its defining feature is an irregular rhythm with at least three different P-wave morphologies and variable PR intervals, reflecting several ectopic atrial foci firing at different rates. Chronic obstructive pulmonary disease fits this pattern best because COPD frequently causes hypoxemia, hypercapnia, and inflammatory stress on the atrial tissue, leading to the disorganized atrial activity that MAT requires. The other conditions listed are not classic triggers for MAT; they more commonly relate to other tachyarrhythmias—hypertension and coronary artery disease are more associated with atrial fibrillation, and hyperthyroidism can cause tachycardias in general but not specifically MAT.

MAT arises most often in the setting of significant lung disease, where hypoxemia and atrial irritability create multiple competing atrial pacemaker sites. Its defining feature is an irregular rhythm with at least three different P-wave morphologies and variable PR intervals, reflecting several ectopic atrial foci firing at different rates.

Chronic obstructive pulmonary disease fits this pattern best because COPD frequently causes hypoxemia, hypercapnia, and inflammatory stress on the atrial tissue, leading to the disorganized atrial activity that MAT requires. The other conditions listed are not classic triggers for MAT; they more commonly relate to other tachyarrhythmias—hypertension and coronary artery disease are more associated with atrial fibrillation, and hyperthyroidism can cause tachycardias in general but not specifically MAT.