Coronary Artery Disease USMLE Step 1 Practice Question
A 58 year old man is admitted for an inferior wall myocardial infarction. On hospital day 1 he develops episodic dizziness. Telemetry shows progressive prolongation of the PR interval until a QRS complex is dropped, after which the cycle repeats. Which of the following is the most likely site of conduction delay?
Answer choices
- APurkinje fibers
- BBundle of His
- CSinoatrial node
- DRight bundle branch
- EAtrioventricular nodeCorrect answer
- FLeft anterior fascicle
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