How is unstable angina typically characterized?

Unstable angina is typically characterized by chest pain or discomfort that lasts longer than 20 minutes. This condition is a type of coronary artery disease and is often a sign that a heart attack may occur soon. The duration of pain is a critical factor; prolonged episodes indicate a more severe, unstable situation, as opposed to stable angina, which tends to occur predictably and for shorter durations.

While unstable angina can sometimes be relieved by rest or medication, this relief is not consistent, and the pain often occurs at rest or with minimal exertion, marking a distinct difference from stable angina. Additionally, nausea may accompany some episodes of angina, but it is not a definitive characteristic of unstable angina itself and can vary widely among individuals. The key feature to recognize is the extended duration of pain, making it a serious condition that requires immediate medical attention.