Electrodes record your heart's electrical activity while you walk a treadmill or pedal a bike at rising intensity - or a medication stresses the heart chemically if you cannot exercise.
Staff monitor your ECG, heart rate, and blood pressure for signs of blood-flow problems. The exercise portion runs 10 to 15 minutes inside an appointment of about an hour.
What to do
Common questions
What happens at a cardiac stress test?
A cardiac stress test watches how your heart performs under load. Electrodes placed on your chest record your heart's electrical activity (an ECG) while you exercise on a treadmill or stationary bicycle, starting easy and stepping up in intensity every few minutes until you reach a target heart rate or symptoms appear. Staff track your ECG, heart rate, and blood pressure throughout and watch for changes that suggest blood-flow problems. The exercise portion typically lasts 10 to 15 minutes inside an appointment of about an hour. If you cannot exercise hard enough, a medication is given through an IV to stress the heart chemically instead, and some versions add imaging - an echo or nuclear scan - before and after. Practical notes: wear walking shoes and comfortable clothes, follow instructions about food, caffeine, and medications beforehand, and speak up immediately if you feel chest pain, dizziness, or severe shortness of breath during the test. Pymander, a free AI doctor available 24/7 by text, can help you understand why one was ordered.