While the severity of angina varies, this condition is caused by reduced blood flow to the heart, states Mayo Clinic. Reduced blood flow is usually caused by coronary artery disease, which occurs as a result of plaque buildup on arterial walls. Red blood cells are responsible for carrying oxygen.
A person experiencing angina symptoms is not getting the appropriate amount of oxygen, which the heart needs to survive, explains Mayo Clinic. Other causes of arterial narrowing are stress, smoking, cold temperatures and heavy meals. Stable angina usually occurs when a person exercises. This happens because the heart requires more blood with exertion.
Unstable angina occurs when fat deposits or plaques rupture, causing a blood clot, according to Mayo Clinic. This blocks or narrows an artery, and this decreases blood flow to the heart. This type of angina is dangerous and most often requires medical treatment, as a heart attack can occur. Variant angina occurs when the artery spasms, temporarily decreasing blood flow to the heart. This occurs even when a person is resting and causes chest pain. This type of angina is treated with medications if required. Angina symptoms that are new or different may signal unstable angina. Symptoms of angina include dizziness, being short of breath, fatigue, sweating and pain in the chest. Pain in the neck, jaw, shoulder or back that is accompanied by chest pain is also a symptom of angina.