Exercise-induced symptomatic ischaemia predicts a poor long-term prognosis after acute myocardial infarction

STUDY OBJECTIVES: To evaluate the long-term prognostic significance of symptomatic ischaemia during exercise testing performed 3 weeks after acute myocardial infarction (AMI). DESIGN: A prospective study with long-term follow-up. SETTING: A Cardiac Rehabilitation Clinic in a University Hospital. SUBJECTS: A total of 446 patients were allowed to perform exercise testing 3 weeks after AMI and followed for 72 +/- 20 months. MEASUREMENTS AND RESULTS: Patients were divided into three groups according to whether they had no ECG evidence of ischaemia during exercise testing (334 patients), silent ischaemia (90 patients) or symptomatic ischaemia (22 patients). Cardiac death was significantly more frequent in patients with symptomatic ischaemia when compared with silent ischaemia (31.8% vs. 7.8%, P < 0.01) or when compared with no ischaemia (31.8% vs. 10.2%, P < 0.01). The three groups had a low cardiac mortality during the first 48 months of follow-up. The prognosis of patients with symptomatic ischaemia worsens markedly thereafter. The results of exercise testing did not predict recurrence of myocardial infarction. Coronary revascularization was performed in 34.4% of those without ischaemia, 47.8% of those with silent ischaemia and 45.5% of those with symptomatic ischaemia (P < 0.01). CONCLUSIONS: Patients with symptomatic ischaemia have a good prognosis during the first 4 years of follow-up. Their prognosis worsens thereafter as opposed to patients with or without silent ischaemia. This high-risk group of patients with symptomatic ischaemia deserves optimal management including revascularization when appropriate.