How Do You Test for Angina?

Introduction

Effective diagnosis of any disease condition significantly impacts the treatment process of the disease. Do you know that a wrong health condition diagnosis will affect any treatment effort? This article discusses various diagnostics tests for angina and treatments. 

What is Angina?

Angina refers to chest pain experienced when the heart does not get the required blood and oxygen.¹ The root cause of angina is atherosclerosis, where there is fatty build up in the arteries, affecting blood movement in the body. Angina has similar symptoms to heart attack and can also be a symptom of coronary artery disease.¹⁶

In 2013, More than two million people in the UK were diagnosed with angina. Angina is categorised into stable, unstable, variant, and microvascular angina. ²

Symptoms

According to the American Heart Association, people suffering from angina can show all or some of the following symptoms:

Shortness of breath and pain in the centre of the chest can spread to the shoulder, neck, & arm, dizziness, nausea, and excessive sweating.

Causes/Risk Factors

Some factors can increase your chances of experiencing angina. These include: 

• High blood pressure 
• Diabetes
• Smoking 
• Unhealthy diet 
• Obesity 
• Physical inactivity 
• Ageing (men over 45 years have a higher risk of experiencing angina)

Diagnosis

Your health provider can perform various procedures and tests to diagnose you with angina or cardiovascular disease. This section describes the processes involved in the test, what to expect, how to prepare for the test and other relevant information.⁵

Electrocardiogram (ECG)

This test measures the heart's electrical activity, which helps detect any abnormal heart rhythm, whether fast or slow. This test also shows any abnormality in the heart wall’s appearance if it is enlarged or thicker than normal due to too much pressure.

How is the test done?

This test can be carried out by your GP and mostly in the emergency department of the hospital. Small sticky patches called 'electrodes' are placed on the chest and sometimes on the arms and legs. The ECG recording machine is connected to the patches through wires.

This test is not painful and does not have any risk associated with it. The only downside to this test is that a normal ECG reading does not necessarily mean that the person is not having an abnormality in the heart and vice versa.

Stress test

A stress test is also known as an exercise electrocardiogram or an exercise tolerance test. This test determines the level of stress/work your heart can handle. This test is like an ECG, but the readings are taken before, during, and after an exercise on the treadmill. The treadmill's speed is increased faster, and it is tilted to imitate the effect of climbing a small hill. Blood pressure and pulse readings are also recorded. 

This test is done to diagnose coronary heart disease since a reduced oxygen supply can be easily detected during the stress test. A positive exercise ECG results indicate that the heart's electrical activity is abnormal, which means coronary heart disease is possible. Normal electrical activity of the heart during the test means a negative exercise ECG result.

A stress test is also conducted to determine if the heart functions correctly after heart surgery or coronary angioplasty. It is done to detect heart problem symptoms such as chest pain and shortness of breath.⁶

There is little or no risk attached to this test, especially for healthy people. A health professional will be present throughout the test. You will be told to stop walking on the treadmill if you experience chest pain, shortness of breath, abnormal heart rate, or high/low blood pressure.

What to do before taking a stress test

It is recommended to inform your doctor about your other medications because the doctor might tell you not to take them before the test.

Wear loose-fitting clothing and comfortable footwear to make the treadmill movement easy.

It is advisable to avoid eating food 2-4 hours before the test. However, feel free to drink water.

Echocardiogram

This is a diagnostic test that shows accurate information about the condition of the heart and its pumping action. This test uses high-frequency sound waves to show the image of activities in the heart, just like a pregnancy ultrasound. 

The echocardiography test is also known as heart ultrasound. A trained sonographer can only carry out this test. And it is done in a private hospital room or ward because the patient will need to undress from the upper part of the body.

How is the test done?

It is required that you lie down on the bed; a gel will be applied on a probe (recorder) that is moved across your chest. This probe helps to record images of the heart activity. A specialist will be needed to interpret the result.

Echocardiography might be required to diagnose heart murmur, heart attack, chest pain, and a congenital heart defect. The test usually takes an hour, and it is a painless procedure with no risk attached to it.

What can an echocardiography test detect?

The echocardiography detects the following:

• Size and shape of the heart, movement of the heart 
• The activity of the heart valves; whether they are working correctly
• Any abnormal growth around the heart valves
• Narrowed heart valve
• Blood clots within the heart chamber
• Holes in the heart, and faulty blood vessels leaving and entering the heart

Nuclear stress test

This test helps measure the severity of heart problems such as coronary heart disease. A nuclear stress test is usually done when you have chest pain and or shortness of breath.

Risks associated with this test include dizziness, low blood pressure, and heart attack. The radiotracer will leave your body naturally through stool or urine.

How is the test done?

Images of your heart blood supply are taken with an imaging machine after being injected with the radiotracer while at rest and after exercise, such as walking on a treadmill.

Like the stress test mentioned earlier, a sticky patch called an electrode would be fixed on your chest, legs, and arms to take your ECG. But an IV line will be inserted into your arm, into which a radiotracer is injected. Also, the blood pressure will be taken as well. Your breathing ability during exercise will be measured by breathing into a tube.

A stress test will be carried out, and you will be asked to stop once you develop any chest pain, shortness of breath, very high or low blood pressure, or dizziness.

You will get another dose of radiotracer immediately after the exercise. Then another scan will take an image of your heart and blood vessels. The sticky patch is also connected to measure your ECG, and all other vitals taken before exercising are repeated all over.

The rate of blood supply in the heart will show if there is a problem with your arteries or heart.

Chest X-ray

This test shows the picture of the heart, lungs, and chest bones but does not show the heart's internal structures. It helps reveal the position and size of the heart, blood vessels, and lungs.

The test is done in the hospital, where you will be given a specific posture to take next to the x-ray film. An x-ray machine is turned on for less than a second. A beam of rays passes through the chest examined and produces an image on the unique photographic film.

The x-ray emitted into the body is one-fifth of a person's daily dose from a natural source (e.g., the sun) per year. So, it is not considered a dangerous procedure, although pregnant women are not advised to undergo the test.

Blood tests

Blood tests focus more on measuring the level of certain enzymes associated with the heart muscle and heart attack. These enzymes include troponin and creatine kinases. The test is done by getting a blood sample from the person to be tested.

Testing positive for heart muscle damage, a condition experienced as angina, will indicate a higher troponin level in such a person's blood. Also, creatine kinase is usually released in high quantities into the blood during a heart attack, so high levels of this enzyme indicate that you have had a heart attack.

A blood test is also carried out to measure cholesterol (bad or good) in your blood. High bad cholesterol levels in the blood are the primary source of cholesterol build-up that blocks or narrows the arteries' size, which affects the blood supply in the heart. Higher or lower triglycerides in the body can indicate coronary heart disease - experienced as chest pain/angina.

Coronary angiography

This test is carried out to detect any blocked coronary artery. The test can only be performed in the hospital heart catheterisation laboratory, and specialist doctors and technicians do it. Coronary angiography shows x-ray images that make any problem in the blood vessel visible to the doctor.

How is the test done?

Coronary angiograms are done by carrying out a cardiac catheterisation. A thin hollow tube called a catheter is passed through a large blood vessel (artery) up to the heart. The tube is filled with a special fluid dye that makes the arteries visible in the x-ray scan. You may be administered medicine before the procedure to make you relax. The test is done while lying down.

The common part of the body that is punctured to access a large blood vessel is usually the groin or arm. When the catheter is passed into your blood vessel, you might be uncomfortable. However, the place is usually numb before the insertion is done.

Before taking the test, you should inform your doctor if you are on any medication or are allergic to anything.

The risk associated with this procedure

• The puncture site might leave a small bruise on the body
• The special fluid filled in the catheter makes some people get itchy
• The puncture site might get swollen if bleeding continues after leaving the hospital. Call the emergency number

Cardiac computerised tomography (CT) scan

This test is a non-invasive one that takes a detailed picture of your heart and blood vessels; the picture is then formed into a full 3D model of the heart.

This test helps your doctor detect heart problems or blood vessels around the heart and within the body.

Medicines such as beta-blockers are usually administered to slow down your heartbeat, or nitro-glycerine to help dilate the blood vessel arteries.

Before the test is done, you will be injected with a contrast dye to show a clearer picture of your blood vessels.

The CT scanner is usually a large, tunnel-like machine. During the test, you will need to lie on a table, which will slide into the scanner.

The risk associated with this test is that the contrast dye injected into your body might cause more damage to the kidney if you have known chronic kidney disease. 

Multiple CT scans in people younger than 40 can predispose them to cancer, because radiation is used during the scan.

Pregnant women must inform the doctor before the test so that provisions will be made to protect the foetus during the scanning process.

Cardiac MRI

Magnetic Resonance Imaging (MRI) is mostly done to investigate the internal part of the heart and blood vessels. This test shows a detailed picture of the heart and blood vessels with the aid of radio waves and magnets.

The test is quite like a CT scan, but you will be required to spend at least an hour in the scanner. You will be required to take off any metal objects on you. Anyone with an implanted hearing aid or any foreign metal cannot undergo this test.

Treatments

It is recorded that angina affects more than 10 million in the USA. Hence an effective treatment plan is very important, but it depends on the type and root cause of the chest pain. It can include either surgery, administration of medication, or lifestyle change. Treatment is usually targeted at reducing the risk of developing heart disease, reducing the severity and pain or discomfort caused by angina, and the condition's frequency.

Medication

Medication administered depends on what characterised the chest pain. Examples of commonly prescribed medication according to the American Heart Association could include:

• Aspirin. This hinders blood clots from forming and also helps to prevent plaque build-up in the artery. Aspirin is usually given to people experiencing unstable angina.
• Calcium Channel Blockers, e.g. verapamil and amlodipine (Norvasc). This medication interrupts the movement of calcium into the heart and blood vessels cell.
• Cholesterol-Lowering Medications such as Niacin
• Vasodilators, e.g. Nitroglycerin, These dilate and relax blood vessels.

Lifestyle changes for angina

Maintaining a healthy lifestyle has been proven to lower the risk of developing angina and other heart-related problems. Try to:

• Avoid smoking and reduce your alcohol intake.
• Eat healthy: limit your intake of high cholesterol-containing foods.
• Maintain a healthy weight by engaging in regular exercise.

When should I contact my doctor?

Suppose you notice any abnormality like bleeding after taking any test like the coronary angiography. You should contact your doctor if you notice any unexpected life-threatened symptoms after taking prescribed medications.

Conclusion

Angina can be effectively treated once it is rightly diagnosed. So contact your health provider immediately if you notice any chest pain that keeps reoccurring and does not go immediately after resting.