What primarily causes angina?

Angina primarily arises from myocardial ischemia, which occurs when the heart muscle does not receive enough oxygen-rich blood. This insufficient blood flow is often the result of atherosclerosis, a condition characterized by the buildup of plaques in the coronary arteries. These plaques can narrow the arteries, thereby restricting blood flow, especially during periods of increased demand such as physical exertion or emotional stress.

While factors like blood vessel dilation and rapid heart rate can influence heart function, they do not directly cause angina. Blood vessel dilation might actually relieve symptoms by improving blood flow, and a rapid heart rate can exacerbate the condition but is not a primary cause. Emotional stress is a recognized trigger for angina, as it can lead to increased heart rate and blood pressure, resulting in heightened oxygen demands. However, the underlying cause remains myocardial ischemia due to atherosclerosis, making it the principal factor in angina.