Cardiovascular Medicine: Item 68

Cardiovascular Medicine > Coronary Artery Disease > Chronic Stable Coronary Artery Disease > Treatment > Secondary Risk Factor Reduction

Normal Lab Values

A 49-year-old man is evaluated in the emergency department for mild chest discomfort accompanied by nausea and dyspnea which began 2 hours ago. Antacids provide no relief for the discomfort. He has never had similar symptoms, has no significant medical history, and takes no medications. His older brother had a myocardial infarction 9 months earlier, and his father had coronary artery bypass graft surgery 12 years ago.

The patient's blood pressure is 109/78 mm Hg and pulse rate is 88/min. Cardiac examination reveals no jugular vein distention, no carotid bruits, a normal S1 and S2, with no gallops, rubs, or murmurs. The chest is clear, and examination of the abdomen and extremities is normal. Troponin level is 6 ng/mL (6 μg/L) (normal <0.5 ng/mL). Electrocardiogram shows a 1-mV ST elevation in leads II, III, and aVF.

He is treated with enoxaparin, aspirin, metoprolol, and glycoprotein receptor blockers and taken to the cardiac catheterization laboratory. A drug-eluting stent is placed in a subtotally occluded right coronary artery. Echocardiogram on day 2 of hospitalization shows normal left ventricular wall motion, no mitral regurgitation, and no pericardial effusion. By day 4, he has no complications and is prepared to be discharged.

In addition to aspirin, clopidogrel, and metoprolol, what medications should be given?

A Atorvastatin
B Lisinopril
C Warfarin
D Niacin
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Answer and Critique (Correct Answer = A)
Key Points
  • In patients with an acute coronary syndrome, statin therapy is indicated regardless of the serum cholesterol level.
  • In patients treated with coronary artery stenting for coronary artery disease, statin therapy is recommended even in the absence of elevated total cholesterol.

This patient has survived a small inferior myocardial infarction and was successfully treated with a coronary drug-eluting stent. At discharge, he should receive aspirin, metoprolol, clopidogrel for at least 180 days, and a statin regardless of his serum cholesterol level. In patients with coronary artery disease, especially those presenting with symptoms as well as those undergoing revascularization either by stenting or bypass graft surgery, statin therapy reduces late cardiovascular events despite having minimal or no effect on the angiographic appearance of the coronary artery.

The PROVE IT-TIMI 22 study compared moderate-dose statin (pravastatin 40 mg daily) to high-dose statin (atorvastatin 80 mg daily) in patients hospitalized for acute coronary syndrome. The median LDL cholesterol levels achieved were 95 mg/dL by the pravastatin group and 62 mg/dL for the atorvastatin group. Those receiving atorvastatin had a 16% reduction in the composite endpoint of death from any cause, myocardial infarction, unstable angina requiring rehospitalization, coronary artery revascularization, and stroke during 2 years of follow-up. These results showed evidence of benefit from early aggressive LDL cholesterol lowering with high-dose atorvastatin.

Lisinopril is an antihypertensive, afterload-reducing therapy that is most effective for those with hypertension or large myocardial infarctions, especially of the anterior wall. This young patient has relatively low blood pressure and normal left ventricular wall motion. An angiotensin-converting enzyme inhibitor is optional in this setting.

Warfarin is not indicated after ST-elevation myocardial infarction treated by stenting unless there is another indication such as atrial fibrillation, deep venous thrombosis, or intracardiac thrombus.

Niacin for hypertriglyeridemia may be needed, but at this time the triglyceride values are not reported and may be falsely elevated early in the course of ST-elevation myocardial infarction. The first line of treatment would be statins even for normal LDL cholesterol levels in patients with documented coronary artery disease. The combination of statins with a fibrate is attractive for persons who have both high serum cholesterol and high triglycerides or for those who continue to have elevated triglycerides after reaching their LDL cholesterol target on statin therapy.

Bibliography
  1. Schwartz GG, Olsson AG, Ezekowitz MD, Ganz P, Oliver MF, Waters D, et al. Effects of atorvastatin on early recurrent ischemic events in acute coronary syndromes: the MIRACL study: a randomized controlled trial. JAMA. 2001;285:1711-8. [PMID: 11277825] [PubMed]
  2. Pasternak RC, Smith SC Jr, Bairey-Merz CN, Grundy SM, Cleeman JI, Lenfant C, et al. ACC/AHA/NHLBI clinical advisory on the use and safety of statins. J Am Coll Cardiol. 2002;40:567-72. [PMID: 12142128] [PubMed]
  3. Cannon CP, Braunwald E, McCabe CH, Rader DJ, Rouleau JL, Belder R, et al. Pravastatin or Atorvastatin Evaluation and Infection Therapy-Thrombolysis in Myocardial Infarction 22 Investigators. Intensive versus moderate lipid lowering with statins after acute coronary syndromes. N Engl J Med. 2004;350:1495-504. [PMID: 15007110] [PubMed]