Which statement is not true about MAT?

Which statement is not true about MAT?

• A. MAT shows three or more P-wave morphologies
• B. PR interval varies
• C. Heart rate is typically over 100 bpm
• D. Delta wave is present

Answer: (D)

MAT is defined by atrial activity arising from multiple foci, which creates three or more distinct P-wave morphologies and an irregular rhythm. Because the impulse source changes from beat to beat, the PR interval varies as well. The heart rate is usually tachycardic, often over 100 bpm. A delta wave, however, is not a feature of MAT; delta waves indicate pre-excitation through an accessory pathway, as seen in Wolff-Parkinson-White syndrome. Therefore, the statement that a delta wave is present does not fit MAT.

MAT is defined by atrial activity arising from multiple foci, which creates three or more distinct P-wave morphologies and an irregular rhythm. Because the impulse source changes from beat to beat, the PR interval varies as well. The heart rate is usually tachycardic, often over 100 bpm. A delta wave, however, is not a feature of MAT; delta waves indicate pre-excitation through an accessory pathway, as seen in Wolff-Parkinson-White syndrome. Therefore, the statement that a delta wave is present does not fit MAT.