Q. What is ST segment depression at rest?

ST- segment depression has become severe, that is, 3 to 4mm or more in vigorous asymptomatic subjects. If the patient is known to have severe CAD or angina at low workloads of if the patient is known to have severe CAD or angina at low work loads or if the patient has ST segment depression at rest, exercise should be terminated with only minor increases in ST segment depression over the baseline tracing. One should also terminate exercise when ST-segment depression exceeds 2mm if the onset of ischemia is at low work loads.