What characterizes unstable angina?

Unstable angina is characterized by partially blocked blood flow to the heart, which results in chest pain or discomfort. This condition occurs when there is a sudden worsening of previously stable angina, often manifesting with more severe pain, increased frequency of episodes, or pain that occurs at rest.

The distinction of unstable angina lies in its unpredictability and the potential to progress to a heart attack, making it a critical condition that requires immediate medical attention. The chest pain associated with unstable angina may not be triggered by physical exertion or stress, and patients frequently describe it as more intense or different from their usual angina episodes.

In contrast, stable blood flow denotes a condition where the heart is receiving adequate blood supply, thus ruling out the characteristic pain associated with unstable angina. A complete blockage of a coronary artery would lead to a myocardial infarction (heart attack) rather than unstable angina. Lastly, a condition with no symptoms does not apply, as chest pain is a primary symptom of unstable angina. Overall, the key aspect of unstable angina is the compromised blood flow that leads to notable symptoms such as chest pain, distinguishing it from other conditions related to coronary artery disease.