MSD Manual

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MSD Manual
Veterinary Manual
The trusted provider of veterinary information since 1955

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VETERINARY PET
ECG, high-grade second-degree atrioventricular (AV) block, dog
ecg-high-grade-second-degree-atrioventricular-block-dog-kittleson-sized
ECG, high-grade second-degree atrioventricular (AV) block, dog

    Each QRS complex (R) on this ECG of a dog is accompanied by two or three P waves. This indicates that the SA node depolarization is only traversing the AV node 1 out of every 2 or 3 times.

Courtesy of Dr. Mark D. Kittleson.

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