USMLE Step Three

A 92-year-old male with hypertension and gout presents to the emergency department with an episode of passing out while sitting at the table. He has felt generally weak for the past 4 days. He denies any chest pains, shortness of breath or other complaints. His medications include metoprolol and celecoxib. His blood pressure is 115/65 mm Hg, heart rate 42 bpm, respirations 12 breaths per minute and he is afebrile. His physical examination reveals normal lung sounds; a regular, bradycardic rhythm with varying intensities of the S1 heart sound; and intermittent large intermittent cannon A waves in the jugular venous pulsations. His laboratory studies are normal. His ECG is below. What is the appropriate treatment?

A 45-year-old male with a history of hypertension and dyslipidemia presents to the emergency department with substernal chest pressure for 1 hour. The pain occurred at rest, is 10/10 in severity and is associated with shortness of breath. His temperature is 37.1 C, blood pressure 80/50 mm Hg, heart rate 90 bpm and respirations 20 breaths per minute. His laboratory studies are normal. His ECG is below. What is the appropriate initial management?

A 56-year-old male presents to the emergency department with chest pain, nausea and vomiting. His temperature is 37.2, blood pressure 110/70 mm Hg, heart rate 50 bpm, respirations 20 breaths per minute and oxygen saturation normal on room air. Physical examination reveals normal breath sounds, an S4 heart sound and a regularly irregular rhythm. Laboratory studies reveal an elevated troponin I level and appropriate therapy for acute coronary syndrome is started. His ECG is below. What is the treatment for his heart rhythm?