The patient displays stable angina pectoris with an underlying risk factor for atherosclerosis (smoking). Fixed atherosclerotic plaques obstructing >75% of coronary arteries are associated with stable angina.
Chronic (stable) angina pectoris is characterized by 3 distinct features: deep, poorly localized chest or arm pain, reproducible with physical exertion, and relieved with 5 minutes of rest or use of sub-lingual nitroglycerin. Hypertension, cigarette smoking, and hyperlipidemia are three major risk factors for atherosclerosis.
Zanger et al. discuss the management of stable angina. Chronic stable angina is able to be appropriately managed with medical therapy in the majority of patients. Medications used in the treatment of chronic angina include aspirin, beta-blockers, cholesterol-lowering agents and other anti-ischemic drugs that can ameliorate angina and improve the patient's quality of life.
Hansson reviews inflammation, atherosclerosis and coronary artery disease. Atherosclerosis is the accumulation of atheromatous lesions that cause asymmetric focal thickenings of the arterial intima. The atheromas consist of cells, connective-tissue, lipids, and debris. Inflammatory and immune cells are also an important component of an atheroma. An atheroma is preceded by a "fatty streak", which is an accumulation of lipid-laden cells beneath the endothelium. Fatty streaks can be found in young people, yet never cause symptoms. They may progress to atheromas or eventually disappear.
Illustration A depicts an overview image of stable angina. Illustration B depicts the usual progression of atherosclerosis from a fatty streak all the way to an occluding thrombus formation.
Answer 2: Plaques obstructing <75% are usually asymptomatic.
Answer 3: Ulcerated fibrous plaques are associated with unstable angina.
Answer 4: PE's usually do not typically present like the vignette above describes.
Answer 5: Ruptured plaques with a fully obstructive thrombus are associated with a transmural MI.
Zanger DR, Solomon AJ, Gersh BJ. Contemporary management of angina: part II. Medical management of chronic stable angina. Am Fam Physician. 2000 Jan 1;61(1):129-38. Review.
PMID:10643954 (Link to Abstract)
Hansson GK. Inflammation, atherosclerosis, and coronary artery disease. N Engl J Med. 2005 Apr 21;352(16):1685-95. Review.
PMID:15843671 (Link to Abstract)
USMLE World Step 1 QBank Question #36. Copyright © USMLEWorld, LLC 2012.