Overview of Exercise Stress Testing

The treadmill stress test is among the oldest tools in cardiology, and this review’s quiet point is that most clinicians read it too narrowly — fixating on the ECG tracing while ignoring richer information the test hands them for free.

Its diagnostic limits are stated honestly: sensitivity around 60–70%, specificity about 85%, best suited to patients at moderate pretest probability. But the prognostic payload extends well past ST-segment changes. Exercise capacity is the standout — someone who reaches 12 METs has roughly 95% five-year survival regardless of what the ECG shows. Heart-rate recovery is another: a drop of fewer than 12 beats in the first minute after stopping signals two-to-three-fold higher mortality. Blood-pressure response and the pattern of any changes round out the picture.

The practical takeaway is to read the whole test — functional capacity, heart-rate response and recovery, blood pressure — not just the tracing, and to know the danger signs that should stop it.

We rate the evidence moderate: a clear, peer-reviewed teaching review, though dated (2006) and from a regional journal. Its clinical significance is moderate and partly overtaken by events — imaging stress tests and the ISCHEMIA trial have since reshaped the approach to stable coronary disease — but its core lesson about extracting prognosis from exercise capacity and heart-rate recovery remains sound and underused.