Cardiac Diagnostic Tests

Early diagnosis of cardiac diseases plays a vital role in the treatment of heart problems. Various tests are available, which not only provides doctors the guidelines for deciding the course of treatment for their patients, but also gives prior warning to the patients for improving their lifestyle and taking preventive measures for minimising the risk of a heart disease.


Resting Electrocardiogram (ECG) is a simple test which is commonly used for basic evaluation of cardiac status. It records intrinsic electrical activity of the heart by placing electrodes on the limbs and chest. The recorded signals provide useful information regarding previous damage to the heart muscles, enlargement of heart chambers and abnormalities in the electrical system of the heart.

The most valuable role of ECG is in diagnosis and initial management of acute heart attack.

Preparations for the test

No special preparation is required.


In this test, the Electrocardiogram (ECG) is continuously monitored for 24 to 48 hours. The signals are recorded on a special recorder which is worn by the patient. This prolonged monitoring records transient rhythm or EGG abnormalities. This test is especially useful in patients with palpitations, giddiness or fainting spells. It can also help in assessing response to drug therapy.

Preparations for the test


Treadmill Test (TMT) assesses the response of your heart to increased workload and demand for blood. This is done by recording the ECG while you are walking on a treadmill machine.

Preparations for the test

Once you start walking on the treadmill, your blood pressure, heart rate, general condition and ECG will be monitored continuously. After every three minutes the speed and incline of the treadmill will be increased. You will be encouraged to exercise for as long as you can and the test will be continued till you reach a desired heart rate or cannot exercise any more. After the test, you will be asked to rest while ECG and blood pressure are recorded till your reach the baseline heart rate. All the recordings are analyzed by a cardiologist and the results made available in a few minutes.

Safety of the test

Exercise treadmill testing is very safe. Some patients might experience chest pain during the test. However, the risk of heart attack or abnormal heart beat is extremely low.


It is a diagnostic procedure performed by using ultrasound to take images and measurements of different parts of the heart


Preparations for the test

On the day of the test, you can eat or drink as usual and should take all prescribed medications. No special preparation is needed.

About the test

The test is performed by a cardiologist. You will be asked to change into a hospital gown. Gel is used for better contact between transducers and skin. The test will involve placing a transducer on the chest wall over the heart..


Echocardiography is an indispensable, non-invasive ultrasonic procedure used in the diagnosis and management of cardiac diseases in the fetus, newborns, infants and children. Preparations for the test

There is no need to withhold food or drink. Paediatric patients have to be quiet during the study. They may have to be sedated with a mild oral sedative, in which case no oral feeds should be given until the child is fully awake after the feed.

Fetal Echocardiogram is best performed between 20 and 24 weeks of gestation and no special preparation is required.

About the test

The test is performed by a cardiologist.

Safety of the test

At the present time, adverse effects resulting from application of diagnostic ultrasound have not been reported and the benefits to patients outweigh to risks, if any, that may be present.


Stress Echocardiography is a diagnostic test that uses ultrasound images of the heart to supplement ECG information obtained during a stress test. The results obtained by Stress Echocardiography are comparable to nuclear stress tests and are being used in major medical centres across the world to assess probability of coronary artery blockages or viability of damaged heart muscles.

Preparations for the test About the test

All stress tests are performed under supervision of a doctor. There are two forms of Stress Echocardiogram. If you are able to exercise vigorously on a treadmill, an exercise echocardiogram will be performed. The second method of stressing the heart is with administration of special medication intravenously that simulates exercise.

Safety of the test

Stress Echocardiography is a very safe test. However, some patients could develop chest pain, irregular heart beat or blood pressure changes. Stress Echocardiography is as safe as a regular nuclear exercise stress test. It gives the same type of information as a nuclear stress test, but without any radiation exposure.


It is a diagnostic procedure in which a tube with a tiny ultrasound probe is inserted through the patient's mouth and pictures of the heart are obtained using sound waves. The procedure is performed by an experienced cardiologist.

Preparations for the test

You should not eat or drink anything on the day of the test. If the test is in the afternoon, take your morning medicines as usual. If the test is the morning, do not take your routine medicines.

How is the test done?

You will be asked to change into a hospital gown. Your throat will be sprayed with an anesthetic solution to numb it and you will be given an intravenous sedative if required. The TEE tube will be introduced through the mouth into the food pipe and stomach. Initially you will be asked to swallow repeatedly. This will facilitate passage of the tube to pass from the back of the throat and minimize discomfort. It takes 5-10 minutes to obtain different views of the heart.

After the procedure you will be observed for sometime before being allowed to go home. It is not unusual to feel some soreness in the throat for one or two days after the test.

Safety of the test

TEE is a semi-invasive procedure and carries a small risk of trauma to the food pipe or throat.


Occasional blood pressure measurements taken at home or in a clinic at times do not provide adequate information and your physician may ask for this test. This test monitors blood pressure on an hourly basis for 24 hours and readings are recorded on a special recorder. These readings are then analysed by sophisticated equipment and the results are interpreted by an experienced cardiologist.

Preparations for the test


Some patients complain of dizziness or episodic loss of consciousness, with no obvious cause for it. This special test is performed to discern the cause. During the test, patient is tilted head up to a certain angle for up to 45 minutes, while heart rate, ECG and blood pressure is continuously monitored. Any change in heart rate, blood pressure or recurrence of symptoms is carefully observed.

How is the test done? Safety of the test

Some patients have unpleasant feelings during the test. However, rest assured that this is a very safe test