How effective is electrocardiogram for angina?

An ECG records the heart's electrical signals through sensors placed on the skin. It may show changes linked with a current problem, a previous heart injury, an irregular rhythm or another explanation for chest symptoms. Angina can occur when the heart needs more oxygen, such as during exertion, while a resting ECG may be taken between episodes. The clinician therefore combines the tracing with the pain pattern, examination and risk factors.

Describe when discomfort starts, how long it lasts, where it spreads and whether rest changes it. Ask what the ECG showed and whether you need further assessment, such as blood tests, heart imaging or an exercise-based test. Take prescribed medicines as directed and do not increase activity to provoke symptoms unless a clinician has specifically advised supervised testing.

Call emergency services for chest pressure or tightness that is severe, new, worsening or persistent, especially with sweating, breathlessness, nausea, fainting or pain spreading to the arm, jaw or back. Do not rely on a previous normal ECG to judge a new episode. Sit and rest while waiting for help, following local emergency advice.

Ask whether the ECG was recorded during symptoms, what findings matter, and what test should come next if concern remains. You can also ask how to distinguish your usual pattern from a change, which activity is safe, and when to seek emergency help.