Factors that can worsen angina

Angina may worsen when another condition:

• Forces your heart to work harder, which increases the amount of oxygen it needs.
• Decreases the amount of oxygen the heart receives.

In either case, there is an imbalance between the amount of oxygen that your heart needs and the amount that it receives through the blood supply from your coronary arteries. If your heart can't get enough oxygen, your symptoms of stable angina may worsen.

Conditions that may worsen angina symptoms include:

• Atrial fibrillation. When atrial fibrillation worsens angina, you must slow your heart rate down as quickly as possible. Medications such as digoxin, beta-blockers, or calcium channel blockers are often effective at controlling your heart rate. You may also need other medications, called antiarrhythmics, which can stop the irregular beat and bring back your normal, regular heartbeat. If you have prolonged or severe symptoms of angina or if you develop heart failure or low blood pressure, it may be necessary to stop your atrial fibrillation more quickly with an electric cardioversion to your chest.
• Fever and infection. If you develop an infection, it typically causes your heart to beat faster and harder, and may worsen angina. When an infection (such as a urinary tract infection, bronchitis, pneumonia, or influenza) worsens angina, you need to identify the source of the infection and treat it with antibiotics if necessary. You also need to reduce your temperature with aspirin, acetaminophen, or another fever-lowering medication to reduce the stress on your heart. Talk to your doctor about the benefits of the pneumonia vaccine and a yearly flu vaccination.
• Hyperthyroidism. Hyperthyroidism speeds up many of your body's functions, including your heart rate, which can worsen angina. Medications such as beta-blockers can reduce the effect of thyroid hormone on your heart and lower your heart rate. Your doctor may also recommend other medications that gradually decrease the amount of thyroid hormone your thyroid is producing.
• Anemia. Anemia decreases oxygen supply to the heart and can worsen angina. You should receive oxygen therapy and possibly a blood transfusion to increase the amount of oxygen in your blood. Medications that lower your heart rate, such as beta-blockers, can help control angina attacks associated with anemia.You can also take vitamins and iron supplements, according to your doctor's instructions, to help your body manufacture more red blood cells. If you have anemia, you may want to be tested to see if it is caused by a more serious condition, such as a bleeding ulcer or cancer.
• Aortic valve stenosis. Aortic valve stenosis develops when the valve between the lower left chamber (left ventricle) of the heart and the major blood vessel called the aorta becomes narrowed (stenosis). This leaves too small a space for the blood to flow to the body. Because aortic stenosis causes a buildup of pressure inside your left ventricle, the heart compensates by thickening. The thickened heart muscle requires a large amount of oxygen to function properly. If a buildup of plaque has narrowed coronary arteries, the heart begins to suffer from a lack of oxygen, a condition called ischemia. Angina can be more severe when both conditions are present.