Risk stratification in coronary artery disease and special populations

In patients with coronary artery disease (CAD), left ventricular (LV) function, the number of diseased vessels, and the severity of myocardial ischemia are important determinants of survival. These factors can be used to identify subsets of high-risk patients who are candidates for aggressive intervention. Among patients with LV dysfunction, those with left main CAD, three-vessel disease, and one- or two-vessel disease with inducible ischemia are at highest risk. High-risk subsets among those with preserved LV function include patients with left main CAD and those with inducible ischemia and either three-vessel disease or two-vessel disease with involvement of the proximal left anterior descending coronary artery. Thus, exercise testing, assessment of ventricular function and, in selected patients, coronary angiography to determine coronary anatomy are valuable tools in risk stratification. In the primary-care setting, patient characteristics such as gender, race, age, and concomitant medical conditions may also be most useful in identifying high-risk patients. Although women in general have some primary protection against premature CAD, especially prior to the menopause, coronary risk in women who have experienced a cardiovascular event is similar to that in men. Coronary mortality is increased in minority populations, and the presence of other risk factors, such as diabetes and hyperlipidemia, can further increase this risk. Up to 80% of diabetic patients die of cardiovascular disease, 75% of which is CAD. The risk in this population is exacerbated by the abnormalities in lipid metabolism associated with the diabetic state. CAD mortality increases with aging, but it is recommended that elderly patients with CAD also receive risk factor intervention, such as cholesterol-lowering therapy. Consideration of the impact of such therapy on quality of life is especially important in initiating such interventions in the older population.