Treatment of ischaemic heart disease: Role of drugs, surgery and angioplasty in unstable angina patients

The term unstable angina should only be used to describe patients whose immediate prognosis is uncertain and the nature of the unstable disease may vary on a patient to patient basis, making broad categorization of such patients inappropriate. Unstable angina may be caused by extracardiac factors, such as uncontrolled hypertension and tachycardia, disruption of an atheromatous plaque, dynamic or intermittent coronary artery thrombosis, haemorrhagic dissection into an atheromatous plaque, epicardial coronary spasm or progression of atherosclerosis as a result of plaque healing. Control of symptoms using medical therapy with a combination of nitrates, beta-blockers and calcium antagonists is usually quite successful. In the absence of contra-indications, intravenous heparin, and possibly anti-platelet agents, should also be used in the acute phase of treatment. In addition, one aspirin a day is indicated unless there are definite contra-indications. If symptoms are relieved, evaluation and management should proceed as with chronic stable angina. Identification of patients with a poor prognosis should be the main indication for urgent revascularization. One of the best predictors of a poor prognosis in unstable disease is persistent pain despite optimum therapy. Urgent surgery should be considered in any patient with multivessel coronary artery stenosis who has evidence of persistent myocardial ischaemia, despite adequate medical therapy.