A patient with atherosclerotic heart disease experiences chest pain during exertion because:

A patient with atherosclerotic heart disease experiences chest pain during exertion because:

• A. the lumen of the coronary artery is narrowed and cannot accommodate increased blood flow.
• B. one or more coronary arteries suddenly spasm.
• C. a weakened area develops in the aortic wall.
• D. tissues of the myocardium undergo necrosis secondary to a prolonged absence of oxygen.

Answer: (A)

When a person exercises, the heart requires more oxygen, so the coronary arteries must deliver more blood. In atherosclerotic disease, plaques narrow the lumen of the coronary vessels, reducing the maximum blood flow they can provide. Because the normal vessels can’t dilate enough to compensate for the fixed narrowing, the myocardium becomes ischemic during increased activity, causing chest pain known as angina. This differs from a sudden coronary spasm, which can cause chest pain but is usually episodic and can occur independently of exertion. An aortic wall weakness leading to an aneurysm or dissection isn't the typical cause of exertional chest pain in this context. And tissue necrosis from prolonged oxygen deprivation describes a myocardial infarction, which is a more advanced outcome of sustained ischemia rather than the usual exertional angina seen with stable atherosclerotic narrowing.

When a person exercises, the heart requires more oxygen, so the coronary arteries must deliver more blood. In atherosclerotic disease, plaques narrow the lumen of the coronary vessels, reducing the maximum blood flow they can provide. Because the normal vessels can’t dilate enough to compensate for the fixed narrowing, the myocardium becomes ischemic during increased activity, causing chest pain known as angina.

This differs from a sudden coronary spasm, which can cause chest pain but is usually episodic and can occur independently of exertion. An aortic wall weakness leading to an aneurysm or dissection isn't the typical cause of exertional chest pain in this context. And tissue necrosis from prolonged oxygen deprivation describes a myocardial infarction, which is a more advanced outcome of sustained ischemia rather than the usual exertional angina seen with stable atherosclerotic narrowing.