What typically causes angina?

Angina is primarily caused by a lack of oxygen delivered to the heart muscle, which can occur due to various underlying conditions, most commonly coronary artery disease. When the heart muscle does not receive enough oxygenated blood, it can result in chest pain or discomfort, typically described as a pressure or squeezing sensation. This oxygen deficit often arises during physical exertion or emotional stress, when the heart demands more oxygen than usual.

While high blood pressure, stress, and an excessive heart rate can contribute to the overall strain on the heart and might exacerbiate the condition, these factors do not directly result in the oxygen deficit that characterizes angina. The core issue remains the insufficient supply of oxygen to meet the heart's needs, making the understanding of blood flow distribution and oxygen supply crucial in the context of angina.