A 74-year-old man with acute inferior wall myocardial infarction develops bradycardia with a heart rate of 38 bpm. Physical exam reveals cannon A waves in the neck. ECG shows P waves marching through QRS complexes at regular intervals, with QRS duration of 0.12 seconds. Which of the following is the most likely diagnosis?

  1. A)Sick sinus syndrome
  2. B)Sinus bradycardia with bundle branch block
  3. C)Third-degree atrioventricular block with junctional escape rhythmGABARITO
  4. D)Second-degree type II atrioventricular block
  5. E)First-degree atrioventricular block

Explicação

Third-degree (complete) AV block presents with complete dissociation of P and QRS complexes. P waves are regular but unrelated to QRS complexes. With inferior MI, the escape rhythm originates at the AV junction (junctional escape) with a rate of 40-60 bpm and ... Ver explicação completa e trilha adaptativa →

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