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Question 12 of 40Block: Cardiology
Untimed 00:00
CardiologyHigh-yieldMedium

A 62-year-old man comes to the emergency department with 40 minutes of crushing substernal chest pain radiating to the jaw, with sweating and nausea. Blood pressure is 92/58 mm Hg and pulse is 48/min. ECG shows ST-segment elevation in leads II, III and aVF, with reciprocal ST depression in lead aVL.

Occlusion of which artery is most likely responsible?

Educational objective

ST elevation in II, III and aVF places the infarct in the inferior wall, which the right coronary artery supplies in most patients. Bradycardia (SA or AV nodal ischemia) and hypotension (right ventricular involvement) further point to the RCA.

Reference: [Textbook title], [edition], chapter [__], page [___].
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Checking the answer against its sources
AI double-checkQuestion 12, Cardiology
Confirmed
Your answer

Answer supported by the sources
Precise source[Textbook title], [edition]Chapter [__], page [___], section “[section name]”
“[The exact passage from the textbook that supports this answer appears here.]”
Detailed explanation
  1. ST elevation in II, III and aVF localizes the infarct to the inferior wall.
  2. The inferior wall is supplied by the right coronary artery in most people.
  3. Bradycardia and hypotension point to SA/AV nodal and right ventricular involvement, which is also RCA territory.
Also supported by: [Second source], page [___]

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Answer double-checkedQuestion 12, Cardiology
Confirmed
Answer checkedC. Right coronary artery
Precise source[Textbook title], [edition]Chapter [__], page [___], section “[section name]”
“[The exact passage from the textbook that supports this answer appears here.]”
Detailed explanation
  1. ST elevation in II, III and aVF localizes the infarct to the inferior wall.
  2. The inferior wall is supplied by the right coronary artery in most people.
  3. Bradycardia and hypotension point to SA/AV nodal and right ventricular involvement, which is also RCA territory.
Also supported by: [Second source], page [___]

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Thu20:00
Group session: renal and acid-baseSolve 20 questions together, then review
Going
Discussion on question 1042
A
Member

I picked B because of the low bicarbonate. Why is the answer C?

M
Member

Calculate the anion gap first. It is normal here, so think about diarrhea or renal tubular acidosis. I shared my notes on this.

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