A 45-year-old man comes to the hospital with acute onset of severe chest pain and diaphoresis. The patient describes the pain as "squeezing," different from any discomfort he has ever had. He has a past medical history of hypertension, and his father underwent coronary artery bypass grafting at age 50. The patient is diagnosed with acute ST-elevation myocardial infarction and undergoes an urgent coronary intervention with stent placement into the right coronary artery. He is also started on high-intensity atorvastatin therapy, along with antiplatelet therapy and appropriate medications to control blood pressure. Four weeks later, the patient's total cholesterol level is 140 mg/dL, down from 200 mg/dL before discharge. Which of the following has most likely increased as the result of the therapy?

Question

A 45-year-old man comes to the hospital with acute onset of severe chest pain and diaphoresis.  The patient describes the pain as "squeezing," different from any discomfort he has ever had.  He has a past medical history of hypertension, and his father underwent coronary artery bypass grafting at age 50.  The patient is diagnosed with acute ST-elevation myocardial infarction and undergoes an urgent coronary intervention with stent placement into the right coronary artery.  He is also started on high-intensity atorvastatin therapy, along with antiplatelet therapy and appropriate medications to control blood pressure.  Four weeks later, the patient's total cholesterol level is 140 mg/dL, down from 200 mg/dL before discharge.  Which of the following has most likely increased as the result of the therapy?

Quizplus · Accepted Answer

11ec160b_3b8a_66eb_9249_f35b1c28e43b_MD0001_00 HMG-CoA reductase inhibitors (statins) inhibit the rate-limiting enzyme in hepatic cholesterol synthesis. In response to these changes, hepatocytes increase their surface expression of the LDL receptor to increase uptake of circulating LDL. Treatment generally produces a 20%-50% reduction in serum cholesterol and LDL concentration. High-intensity statin therapy reduces the risk of acute coronary events. This risk reduction is greater than that seen with other classes of lipid-lowering medications and is likely due to additional properties of statins. Besides effects on lipids, statins have anti-inflammatory properties, improve endothelial dysfunction, and appear to stabilize atherosclerotic plaques. (Choice A) ApoB-100 is an apoprotein present in VLDL and LDL. Decreases in circulating LDL and VLDL will cause the ApoB-100 concentration to decrease as well. (Choice B) The biliary excretion of cholesterol decreases in patients on statins due to decreased de novo hepatic synthesis of cholesterol. (Choice D) Statins lower serum triglycerides modestly and have only a minimal effect on plasma free fatty acid concentrations. (Choice E) Statins produce small decreases in VLDL. Fibrates and nicotinic acid therapy decrease hepatic production of VLDL and are the mainstay of treatment for primary hypertriglyceridemia (increased VLDL). Educational objective: Treatment with statins causes hepatocytes to increase their LDL receptor density, leading to increased uptake of circulating LDL. __________ References: Statins: a new insight into their mechanisms of action and consequent pleiotropic effects. (http://www.ncbi.nlm.nih.gov/pubmed/18048949)

A 45-Year-Old Man Comes to the Hospital with Acute Onset