Heart conditions - angina

About heart conditions – angina

Angina (also known as angina pectoris, which in Latin means 'squeezing of the chest') is a temporary discomfort or pain that happens when part of your heart muscle is temporarily not able to get enough blood and oxygen to meet its needs.

The coronary arteries located in the heart supply the heart muscle with oxygen and blood. If these arteries are narrowed, the reduced blood flow means that the heart muscle receives less oxygen than it needs to function properly. A common cause of narrowed coronary arteries is atherosclerosis – a condition characterised by fatty plaques, which develop in the artery walls.

Angina is not the same as a heart attack. Angina is associated with only a temporary reduction in your heart’s blood supply and, if relieved, doesn’t damage your heart muscle. Cardiovascular disease risk factors increase the risk of angina.

Symptoms of angina

The pain or discomfort associated with angina usually feels tight, gripping or squeezing, and can vary from mild to severe. Angina is usually felt in the centre of your chest, but may spread to either or both of your shoulders, or your back, neck, jaw or arm. It can even be felt in your hands.

Sometimes, angina is felt in other areas of your body without being felt in your chest. Many people don’t even feel pain – just an unpleasant sensation or discomfort in their chest. Angina may also be experienced as shortness of breath, rather than pain.

If angina symptoms last longer than 10 minutes, call triple zero (000) for an ambulance.

Common triggers of angina

Angina attacks can be prompted by exertion or physical exercise, when the hard-working heart muscle requires greater amounts of oxygen. The pain usually fades away with rest. Other triggers of angina may include:

• high emotion, such as anger or excitement
• cold temperatures
• eating a large meal.

Unstable angina

Angina pain usually occurs with physical activity and goes away after a few minutes of rest. It can also be relieved by angina medicine (nitrate spray or tablets).

Unstable angina usually happens while resting, and can affect people in different ways and at different times. You may get angina early in the morning only, or you may get it when you are resting or even sleeping.

Risk factors for angina

Over time, the coronary arteries are narrowed by a layering of fatty deposits (plaques) in the inner linings of the artery walls. This is called  atherosclerosis. These plaques are caused by a combination of factors, including:

• unhealthy eating
• overweight or obesity
• insufficient physical activity
• smoking
• high cholesterol
• high blood pressure
• unmanaged diabetes
• age
• being male
• genetic factors or having a family history of cardiovascular disease
• ethnicity – such as Māori, Pasifika people and those from South Asian countries, are at higher risk of heart disease
• being a post-menopausal woman
• severe mental illness.

Diagnosis of angina

Angina is diagnosed using a number of tests, including:

• exercise stress test – the heart is monitored using a device called an electrocardiogram (ECG) while you ride a stationary bicycle or walk on a treadmill. The test is halted once angina (chest pain) is triggered
• cardiac catheterisation (angiogram) – a tube, or catheter, is threaded into the coronary arteries via a blood vessel in the groin. A special dye is then injected into the coronary artery. This outlines the artery while movie x-rays are taken. Narrowings and blockages within the artery are outlined by the dye.

Treatment for angina

Angina can be treated and managed with medicines and surgery, and by making healthier lifestyle choices. Treatment may include:

• aspirin – taken daily to help manage the condition and reduce the risk of blood clots
• nitrates – to ease the pain of an angina attack. Nitrates can be taken in many forms, including an aerosol pump spray or a tablet dissolved under the tongue. The side effects of nitrates can include flushing, headache and dizziness – to avoid falls, take medication while sitting down
• medications (statins) to stabilise fatty deposits in the coronary arteries
• medications to lower blood pressure and slow the heart rate – which reduces how hard the heart must work
• lifestyle changes – including quitting smoking, losing excess body fat, switching to healthy eating patterns and doing regular physical activity (such as walking every day)
• surgery – procedures such as angioplasty and bypass surgery are used if the angina doesn’t respond to medications and lifestyle changes.

Only take medications if prescribed by a doctor.

Surgery for angina

Surgery is not a cure for atherosclerosis. Unless substantial lifestyle changes are made, fatty plaques will continue to build up in the artery walls.

The two main types of surgical intervention include:

• coronary angioplasty – a thin tube is threaded into the coronary arteries via a blood vessel in the groin or wrist, in a similar procedure to cardiac catheterisation. A small balloon attached to the end of the tube is inflated, which widens the blocked portion of the artery and allows increased blood flow to the affected part of the heart muscle. Stents (tubular grids) may be inserted to hold open the affected part of the artery. The balloon is then deflated and removed
• bypass surgery – the blockage is bypassed with a section of vein taken from the leg, or artery taken from the forearm or inside the chest. Blood flow is then directed through this newly attached blood vessel, into the coronary artery beyond the narrowing or blockage.

Long-term management of angina

Fatty plaques will continue to narrow the coronary arteries unless you make substantial lifestyle changes under medical supervision – even if you’ve had surgery for angina. Stents can develop plaque over time just like an artery. Lifestyle changes include:

• being smoke-free
• benjoying healthy eating
• being physically active
• managing your blood pressure and cholesterol
• achieving and maintaining a healthy body weight 
• maintaining your psychological and social health
• taking your medicines as prescribed.

People with diabetes should generally aim to maintain their blood glucose levels within the target range and follow the advice from their doctor or diabetes educator.

Angina and heart attack

Angina doesn’t cause any lasting harm to the heart muscle. The danger of leaving the condition untreated, however, is the increased risk of heart attack.

If your symptoms don’t go away within 10 minutes of rest and using your nitrate medicine, you may be having a heart attack. Symptoms of angina that are different to your usual pattern of symptoms (such as increased severity or frequency) can also increase your risk of a heart attack. 

Call triple zero (000) immediately and ask for an ambulance.

Where to get help

• In an emergency, always call triple zero (000)
• Your GP (doctor) 
• Heart Foundation Helpline Tel. 13 11 12