A 54-year-old woman is brought to the emergency department because of a 2-hour history of nausea and retrosternal chest pain. She has a 15-year history of type 2 diabetes mellitus. Her current medications include atorvastatin, metformin, and lisinopril. She is diaphoretic. Her serum troponin level is 3.0 ng/mL (N:

Question

A 54-year-old woman is brought to the emergency department because of a 2-hour history of nausea and retrosternal chest pain. She has a 15-year history of type 2 diabetes mellitus. Her current medications include atorvastatin, metformin, and lisinopril. She is diaphoretic. Her serum troponin level is 3.0 ng/mL (N: < 0.04). She undergoes cardiac catheterization which shows right-dominant coronary circulation and a thrombotic occlusion of the proximal right coronary artery, which supplies blood to the patient's right ventricle and the inferior and posterior portions of the left ventricle.  A drug-eluting stent is placed, and she is discharged 2 days later without complication. After 6 weeks, an echocardiography that shows left ventricular contractile dysfunction with normal right ventricular function.  Which of the following characteristics of the right ventricle compared to the left ventricle best explains these echocardiography findings?

Quizplus · Accepted Answer

Eductional Objective: The right ventricle (RV) is relatively protected from myocardial infarction (MI), and contractile function of the RV usually returns to normal following MI.  Factors contributing to this protection include relatively small muscle mass with high capacity to increase oxygen extraction, perfusion throughout the cardiac cycle, and heightened ischemic preconditioning.

A 54-Year-Old Woman Is Brought to the Emergency Department Because