Which statement best describes MAT findings?

Which statement best describes MAT findings?

• A. There are three or more P-wave morphologies
• B. Delta wave is present
• C. PR interval varies
• D. T-wave inversion

Answer: (C)

Multifocal atrial tachycardia stems from multiple atrial pacemaker sites firing at different times. Because the origin of atrial activation keeps shifting, the P waves come in different shapes and the conduction time from atria to ventricle changes beat to beat. That beat-to-beat change shows up as a varying PR interval on the ECG, which is the clearest single clue that MAT is present. While having several P-wave morphologies is also characteristic, the fluctuating PR interval directly reflects the core phenomenon of multiple atrial foci driving the rhythm, making it the best single descriptor. The delta wave is a sign of Wolff-Parkinson-White syndrome, and T-wave inversion is not specific to MAT.

Multifocal atrial tachycardia stems from multiple atrial pacemaker sites firing at different times. Because the origin of atrial activation keeps shifting, the P waves come in different shapes and the conduction time from atria to ventricle changes beat to beat. That beat-to-beat change shows up as a varying PR interval on the ECG, which is the clearest single clue that MAT is present. While having several P-wave morphologies is also characteristic, the fluctuating PR interval directly reflects the core phenomenon of multiple atrial foci driving the rhythm, making it the best single descriptor. The delta wave is a sign of Wolff-Parkinson-White syndrome, and T-wave inversion is not specific to MAT.