208 SECTION 3 Preventive medicine and public Health SEDENTARY LIFESTYLE has progressed when the patient comes under medical care. Even in the presence of severe CAD, there may be little or no It seems that at least 30 minutes of moderate exercise (. g, warning before MI occurs. After acute medical and surgical fast walking )at least three times per week reduces the risk therapy (tertiary prevention) is provided, the provider of cardiovascular disease. There is increasing evidence that should initiate efforts directed at symptomatic stage preven- sittingitself, independent of the amount of exer sa it is tion(also tertiary prevention in this case) the risk of MI. The uncertainty occurs partly because difficult to design observational studies that completely 3. Symptomatic Stage Prevention avoid the potential bias of self-selection ncipient heart disease may have cues that tell them to avoid Every patient with symptomatic cardiac disease needs evalu potential benefits of even modest. easing emphasis on the ation for risk factors and a plan to reduce the risk of adverse exercise). Nevertheless, there is ine direct effects on lipids and also helps to keep weight down, gone revascularization(opening up blocked arteries)through which itself improves the blood lipid profile. Conversely, percutaneous transluminal coronary angioplasty(cardiac there is a growing appreciation for adverse health effects of catheterization) or coronary artery bypass surgery, the goals sedentariness nclude preventing restenosis and slowing the progression of atherosclerosis elsewhere EXCESS WEIGHT In people who are overweight, the risk for cardiovascular BEHAVIOR MODIFICATION disease partly depends on how the body fat is distributed. Fat Patients should be questioned about smoking, exercise, and an be distributed in the hips and legs (peripheral adiposity eating habits, all of which affect the risks of cardiovascular giving the body a pear shape) or predominantly in the disease. Smokers should be encouraged to stop smoking(see bdominal cavity(central adiposity, giving the body an apple Chapter 15 and Box 15-2), and all patients should receive shape, more common in men than women. Fat in the hips nutrition counseling and information about the types and and legs does not seem to increase the risk of cardiovascular appropriate levels of exercise to pursue Hospitalized patients sease. In contrast, fat in the abdominal cavity seems to be with elevated blood lipids should be placed on a"heart more metabolically active, and the risk of cardiovascular healthy diet(see Chapter 19)and encouraged to continu disease is increased. This is not surprising, because fat mobi this type of diet when they return home. This change in diet lized from the omentum goes directly to the liver, which is the requires considerable coaching, often provided by a special center of the body s lipid metabolism. Centrally located body ized cardiac rehabilitation nurse, dietitian, or both fat is implicated in the insulin resistance syndrome and is asso- ciated with increased sympathetic tone and hypertension Weight loss ameliorates some important cardiac risk OTHER MEASURES The assessment and appropriate management of known risk studies question this conclusion. The most recent findings events in patients with symptomatic CAD in this area suggest that weight gain and loss may result in lasting hormonal and cytokine alt erations that facilitate B. Dyslipidemia regaining weight. Although weight cycling may have spe cific associated risks, whether any such risks are truly inde pendent of obesity itself remains unclear. 3-l6At tion in one or more of the lipids or lipid particles found emia, is a general term used to ibe an abnormal elev expert opinion generally supports a benefit from ape ve/ght on the following with greater benefit clearly attached to sustain the blood. The complete lipid profile provides information loss(http://www.nwcr.ws/).acHievingsustain loss remains a considerable challenge(see Chapter 19) Total cholesterol (TC) High-density lipoprotein(HDL) cholesterol DYSLIPIDEMIA a Low-density lipoprotein(LDL) cholest The risk of progression of cardiovascular disease is increased a Very-low-density lipoprotein(VLDLcholesterol, which in patients with dyslipidemia(abnormal levels of lipids and is associated with triglycerides(TGs) the particles that carry them), which can act synergistically The TC level is equal to the sum of the HDL, LDL, and with other risk factors(see later and also Chapter 5, espe VLDL levels cially Table 5-2, and Chapter 19). Disease progression can be slowed by improving blood lipid levels or by address TC=HDL+LDL+ VLDL other modifiable risk factors(e.g, hypertension, diabete (HDL)+(LDL)+(TGs, that benefit from diet and exercise The"good cholesterol, "HDL, is actually not only cholesterol 2. Therapy but rather a particle(known as apoprotein) that contains cholesterol and acts as a scavenger to remove excess choles- The immediate care and long-term care of patients with terol in the body(also known as reverse cholesterol transport) symptomatic CAD depend on the extent to which the disease HDl is predominantly protein, and elevated HDL levels have