UNSTABLE ANGINA - ARE WE ABLE TO RECOGNIZE HIGH-RISK PATIENTS

It is difficult to identify characteristics of patients with unstable angina that are predictive of a high likelihood of developing clinical events., However, several features have been recognized. Patients wit h a clinical history of previous stable exertional angina symptoms who began to experience rest pain appear to be at risk and tend to have m ore extensively underlying coronary disease. When the ischemic episode s are accompanied by rales, a new or worsening mitral regurgitation mu rmur, or hypotension, there is a high likelihood of significant corona ry artery disease and one should triage these patients to early cardia c catheterization and prompt revascularization. An angiographic featur e that carries a high risk is a lesion in the proximal left anterior d escending or in the left main coronary artery. Certain typical ECG pat terns are very suggestive for a critical narrowing in these coronary a rteries. If chest pain and ST-segment changes recur on vigorous medica l management, early invasive evaluation should be strongly considered. Even so, the left ventricular function is very important prognostical ly. According to serologic tests, the level of C-reactive protein and serum amyloid A protein suggesting that there may be active inflammati on predicts an early poor outcome. However, these serologic abnormalit ies do not have much clinical value. An increased platelet activation and a reduced fibrinolytic capacity play a role in the pathogenesis of unstable angina, but thrombolytic therapy does not improve the progno sis in patients with unstable angina.