What unstable angina means

Angina is discomfort caused when the heart muscle does not receive enough oxygen-rich blood for its needs. The word unstable describes a change in the usual pattern. Symptoms may be new, happen with less exertion, last longer, feel stronger, or appear while resting. It is a warning that the blood supply may be changing and that the situation can progress.

The term does not describe a blood-pressure reading, and it cannot be confirmed from the sensation alone. A [Chest Tightness](/symptoms/chest-tightness/) page explains one common symptom, while [Angina](/conditions/angina/) gives broader condition information. A clinician may need an examination, an electrocardiogram, and blood tests.

Stop what you are doing and rest when symptoms begin. For new, worsening, or rest-related discomfort, contact emergency services or attend an emergency department promptly. Follow any personal angina plan exactly, but do not delay help to monitor symptoms at home or to obtain a blood-pressure reading.

Medical care may include observation, repeat testing, and medicines to improve blood flow or reduce cardiovascular risk. Blood-pressure treatment may be adjusted when needed; [Blood Pressure Medication](/treatments/medical-management/blood-pressure-medication/) should be used only according to the prescribed plan.

Get emergency help for pressure, squeezing, heaviness, or tightness that persists or returns, especially with breathlessness, sweating, nausea, fainting, severe weakness, or discomfort spreading beyond the chest. Do not drive yourself if a heart problem is possible.

Ask your doctor what makes your symptoms unstable, which test results support the diagnosis, what medicine is for immediate use, and which symptoms mean you should call emergency services. Also ask how blood pressure, cholesterol, and smoking affect your prevention plan.