Submaximal predischarge exercise testing after myocardial infarction: prognostic value and limitations

The prognostic value of abnormalities resulting from predischargesubmaximal treadmill exercise testing was evaluated in 222 patientsafter myocardial infarction. The presence of the following variables— ST segment depression and elevation, an abnormal bloodpressure response, limited exercise duration, angina pectoris,ventricular arrhythmias — were predictive of subsequentcardiac events (P<0.001) among the 154 patients with oneor more of these abnormalities. When the presence or absenceof specific variables was assessed, only an abnormal blood pressureresponse, limited exercise duration (P<0.001), and ST segmentelevation and shift (P<0.05), were significantly associatedwith cardiac death. Exercise-induced angina was predictive onlyof the development of subsequent angina (P<0.05), and STdepression was associated only with future coronary surgery(P<0.01). Ventricular arrhythmias had no independent prognosticvalue. Markers of left ventricular dysfunction elicited by submaximalexercise testing are therefore valuable in identifying patientsat high risk of death after infarction. Hallmarks of residualreversible myocardial ischaemia are of limited prognostic importance.The test result may be useful in selecting patients for coronaryangiography.