Thursday 29 March 2018

Testing For Heart Blockages - Step By Step Guide. Dr Vivek Baliga Writes.

One of the most common questions I get asked as a doctor is whether or not a person has ‘heart blockages’.

The term is a very broad one and many a time it is unclear to us as to what the patient is trying to convey. From what I gather, patients wish to know if the blood supply to the heart muscle is reduced and whether they are at a risk of a heart attack.

For the purpose of this article, I will talk about heart blockages in the same context as patients refer to it. This way, I hope to give you a clear understanding as to how we can detect this problem through both non-invasive and invasive methods.

Testing For Heart Blockages

In the first instance, the most important thing for us as doctors is to know what the history of the patient is.

Is there a history of chest pain? 

Is this chest pain any worse when walking and is it relieved upon resting? 

Is the pain any worse when you move or take a deep breath in? 

The answer to these questions can help give us a better idea as to whether or not the pain an
individual is experiencing is heart -related.

If the symptoms are suggestive of heart disease, the first test to perform is an electrocardiogram, or ECG.

Dr vivek baliga heart specialist ecg


An electrocardiogram is useful in detecting whether there are any electrical changes within the heart muscle that have been brought upon by narrowing in the heart arteries.

Please note that it is quite normal for patients to have a completely normal electrocardiogram but still have heart artery disease.

However, if an ECG is conducted at the same time a patient is experiencing chest pain, a normal ECG usually rules out disease. That being said, by looking at the risk factor profile, we
decide whether or not further investigation is required.

The next best test to learn about the health of the heart is an echocardiogram, also called an ‘echo test’.

This is an ultrasound test of the heart that can help find out how well the heart is pumping and how efficient it is. It also looks at whether or not any damage has occurred to the heart muscle due to reduce circulation to a particular part. It can also find out whether there are any holes in the heart or problems with any of the heart valves.

An echocardiogram can sometimes show subtle changes which are indicative of reduced circulation to the heart muscle. I personally have picked up hidden heart disease in many patients just by doing an echocardiogram.

Given that it is a painless test, it is essential that it is performed as a part of a cardiac evaluation.

If the echocardiogram is unremarkable, the next test would be a treadmill test.

The treadmill test is one that will help determine whether the heart is receiving adequate amount of blood during times of stress. By walking on a treadmill at a particular speed, the patient is put under a deal of cardiac stress which should unmask problems with circulation through either changes on the ECG or the occurrence of symptoms such as chest pain.

Once again, it is important to note that a negative treadmill test does not necessarily rule out heart disease completely. In fact, one in every five treadmill tests can be negative despite there being some degree of heart artery narrowing.

Given that it is a non-invasive test, it becomes less sensitive than the invasive tests described below.

Depending on how positive the treadmill test is, further investigations such as an angiogram may be performed. An angiogram can be performed either as a CT scan or as a conventional angiogram in the hospital.

The former is reserved for patients who are at a low to intermediate risk (fewer risk factors) while the latter is reserved for more high-risk patients.

An angiogram is the best test to determine if there are heart blockages. These days they are performed as day procedures and do not require admission to hospital as such.

Do I Need All These Tests?

Not everybody requires all these investigations. Depending on the risk factor profile such as a history of smoking, family history of heart disease, abnormally high cholesterol levels, the presence of high blood pressure and diabetes, a determination will be made as to what test would be appropriate.

The best way to know if you have heart blockages is to speak to your doctor and get yourself tested.