Prognosis of new and worsening angina pectoris.
The natural history of new and worsening angina pectoris was studied in 251 men aged under 70 years. Most were ambulant and all were referred by selected general practitioners to a special hospital clinic over two and a half years. Heart attacks developed in 39 patients, nine of whom died. Seventy-two per cent of the attacks occurred within six weeks of the onset or worsening of angina. Of the 212 patients who did not suffer myocardial infarction and who were clinically reviewed six months after their first attendance 66 had been pain free for the previous three months and 14 had experienced only infrequent attacks of angina. Of the 128 men aged under 65 years who were previously in employment 81% had returned to full-time work six months after their first attendance. A discriminant function analysis using many variables was made to develop a predictive index that would allow patients with new or worsening angina who were likely to develop serious cardiac complications to be identified. This did not prove possible, and the only predictive factor of significance was an increased cardiothoracic ratio. The syndrome of new and worsening angina has a low risk of early death, and many patients are symptom free six months later. In general, emergency coronary arteriography and surgery is not indicated.