Nonconducted PAC in bigeminy

Elderly with HTN, dyslipidemia, S/P CABG is admitted for dizziness. BP in the 160's/90's. CBC, Trop, electrolyes - N. Brain MRI - neg.

What is the cause of the bradycardia? (asymptomatic during this event)

If you look closely at the T waves in V1 and compare the the complexes on the left and during the bradycardia, then you see that the T waves are "pointee". Those distortions in the T waves (clear in V1) are the PAC's. So, the bradycardia is due to non-conducted PAC's.

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