What is the main characteristic of Angina?

Angina is primarily characterized by chest pain or discomfort that can often be described as a sensation similar to indigestion. This is due to the heart muscle not receiving enough oxygen-rich blood, often triggered by physical exertion or stress. The pain typically feels like pressure, squeezing, or fullness in the chest, and can sometimes radiate to other areas such as the arms, neck, jaw, or back. Understanding this key symptom helps in recognizing angina as a sign of underlying heart issues, differentiating it from other conditions that cause different sensations or symptoms.

The other options reflect symptoms that are not associated with angina. Loss of balance is more related to neurological issues, sudden headaches might indicate other conditions like migraines or aneurysms, and extreme fatigue can be a sign of various health problems but is not a direct indicator of angina. Thus, the correct characterization of angina focuses on the typical pain described.