Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (74 page)

   It may be due to active lifestyle, drugs (e.g., estrogens, alcohol, phenytoin, phenobarbital, rifampicin, griseofulvin).

   Low HDL-C Lipidemia

   Familial hypoalphalipoproteinemia (autosomal dominant disorder with HDL-C).

   It may be due to deficiency of apo A-I and apo C-III, abetalipoproteinemia, hypobetalipoproteinemia (<30 mg/dL in women and <40 mg/dL in men), or drugs (isotretinoin, anabolic steroids).

Suggested Reading

Hachem S, Mooradian A. Familial dyslipidaemias: an overview of genetics, pathophysiology and management.
Drugs.
2006;66(15):1949–1969.

ATHEROSCLEROSIS

   Definition

   Atherosclerosis is the condition in which the atheroma (plaque) is the characteristic lesion found in the intima of medium-sized and large arteries as an inflammatory response to injury. The plaques contain lipids, smooth muscle cells, connective tissue, inflammatory cell, and other extracellular constituents.

   Atherosclerosis is responsible for almost all cases of coronary heart disease.

   Plaque stability is variable and can rupture, triggering in situ thrombosis or embolization, leading to potential acute ischemic events.

   Who Should Be Suspected?

   Atherogenesis occurs over years and is initially asymptomatic until ischemia is clinically manifested. Clinical manifestation is dependent on the particular circulatory bed affected. Manifestations include myocardial infarction and angina, intermittent claudication and gangrene, stroke, mesenteric ischemia or renal artery stenosis, aneurysms, and arterial dissection.

   Risk factors for atherosclerosis include age, gender, cigarette smoking, DM, endothelial dysfunction, dyslipidemia, hypertension, and family history.

   Risk assessment models and guidelines derived from these risk factors allow for the matching of intensity of management to the degree of cardiovascular risk. This is critical given the prevalence of established risk factor in the general population and the substantial cost associated with escalating medical therapy. The most well established risk model continues to be the Framingham Risk Score, which serves as the foundation for prevention treatment guidelines (see
http://framinghamheartstudy.org/risk/hrdcoronary.html
)