Final answer:
Angina is chest pain caused by inadequate blood flow to the heart muscle resulting in oxygen deprivation. It can lead to more severe conditions like a heart attack if blood flow becomes entirely blocked. Angina is often associated with coronary heart disease.
Step-by-step explanation:
Angina refers to chest pain or pressure that is typically caused by reduced blood flow to the heart's muscles, resulting in a lack of necessary oxygen to these tissues—a condition known as ischemia. The heart depends on its coronary arteries for oxygen delivery, and when these arteries become narrowed from the buildup of plaque, a situation referred to as coronary heart disease, the result can be angina. This chest pain is often a warning sign of heart disease and may manifest as feelings of pressure or a squeezing sensation in the chest, possibly extending to the back, neck, shoulders, or jaw. Individuals might also experience shortness of breath, sweating, or nausea.
A more severe form of reduced blood flow can lead to a myocardial infarction—commonly known as a heart attack. A heart attack occurs when blood flow to a part of the heart is completely obstructed, often due to a blood clot or the rupture of an arterial plaque, leading to the death of cardiac muscle fibers. While angina is a symptom of coronary heart disease that can occur intermittently, mostly during stress or physical activity, a heart attack is a medical emergency requiring immediate attention.