Final answer:
The key difference between stable and unstable angina is that stable angina involves chest discomfort during exertion and improves with rest, while unstable angina occurs at rest, lasts longer, and requires urgent medical attention.
Step-by-step explanation:
Difference Between Stable Angina and Unstable Angina
The difference between stable and unstable angina is primarily about when the chest discomfort occurs and the severity of the situation. Stable angina involves chest discomfort during exertion, such as exercise and improves with rest or medication. In contrast, unstable angina occurs even at rest, can last longer, and is a sign of a more serious underlying condition, potentially even an imminent heart attack. Unstable angina requires immediate medical attention and is considered a medical emergency.
Stable angina may develop over time as the coronary arteries become narrowed due to the buildup of plaque. When exertion surpasses the limited oxygen supply available through the narrowed arteries, chest pain occurs. However, with rest or the use of nitroglycerin, which dilates the coronary arteries, the pain usually subsides.
Unstable angina is unpredictable and can signal that a part of the heart muscle is not getting enough blood flow, especially during times of rest. It is less predictable and more concerning than stable angina because it can occur without any precipitating exertion and doesn't improve as readily with rest or medication.