Unstable chest pain features include which of the following?

• A. New or unpredictable chest pain lasting longer and not relieved by rest
• B. Pain that is relieved by rest within minutes
• C. Chest pain only during rest
• D. Pain unrelated to heart

Answer: (A)

Unstable chest pain signals acute coronary syndrome, and it’s defined by a change in the pattern of ischemia. The key feature is new or unpredictable chest pain that lasts longer and is not relieved by rest. This indicates that ischemia is occurring more aggressively and at rest or with minimal activity, which is more dangerous than the typical, predictable chest pain patterns seen with stable angina.

In stable angina, chest pain is predictable, usually provoked by exertion, and relieved with rest or nitroglycerin within a short time. Pain that occurs only at rest or is unrelated to heart helps point away from an unstable cardiac process and toward non-cardiac causes or another cardiac syndrome such as vasospasm, not the unstable pattern.

Because unstable angina can progress to a heart attack, this presentation warrants urgent assessment with ECG and cardiac enzymes.