Which condition associated with elevated S-T segments is characterized by severe chest pain at rest?

Vasospastic angina, also known as Prinzmetal angina, is a condition where severe chest pain occurs at rest due to transient spasms in the coronary arteries. These spasms lead to temporary reductions in blood flow to the heart muscle, resulting in ischemia. The characteristic elevation of ST segments observed in an electrocardiogram (ECG) during an episode of vasospastic angina reflects this temporary ischemia, signaling that the heart is not receiving sufficient oxygen at that moment.

Unlike stable angina, which typically occurs during exertion and improves with rest or nitroglycerin, and conditions like aortic stenosis or heart rhythm disorders, vasospastic angina specifically features pain at rest and is often unpredictable. This makes it distinct, as the pain arises not from increased demand but from spontaneous coronary artery constriction. Understanding these mechanisms is crucial for recognizing the different manifestations of angina and their implications in a clinical setting.