Echocardiography – ECHO

What is echocardiography?

Echocardiography (commonly known as ECHO) is an imaging modality (similar to ultrasonography) used to visualize the interior of your heart. An echocardiogram employs special sound waves to produce graphic images of the heart.

What are the indications for echocardiography?

Your physician may order echocardiography for you if you present with features of heart disease.  These include- shortness of breath, swelling in the legs, palpitations, dizziness and chest pain. Echocardiography is also indicated in infants and children in order to detect congenital heart defects.

What can an echocardiography test detect?

An echocardiography test can detect changes in-

The size of heart (Cardiomegaly)- The size of heart increases in conditions such as hypertension (known as hypertrophic cardiomyopathy, it involves the thickening of the walls of the left lower chamber of the heart-the left ventricle). The heart can also enlarge in size secondary to alcoholism, diabetes, and coronary artery disease. In these cases, the disorder is known as dilated cardiomyopathy.

The shape of heart- Apart from the conditions described above, the heart can change shape with advancing age, in tetralogy of Fallot (a congenital disease) and Takotsubocardiomyopathy (a stress-induced disorder).

The functioning of your heart– Any compromise with the blood flow to the heart (either from a previous heart attack or an ongoing cardiac insult) can weaken the cardiac muscles. These weak muscles are unable to pump blood effectively.

The functioning of the heart valves– An echocardiogram can detect if the valves of the heart are opening and closing efficiently. Any stenosis or regurgitation of the valves can be visualized.

Structural imaging of the great vessels– The vessels visualized include the aorta and the pulmonary vessels.

Structural imaging of the pericardium (the covering of the heart)-Diseases such as pericardial effusion and infective pericarditis can be detected.

Congenital diseases– An echocardiography test can detect congenital cardiac diseases in a fetus (fetal echocardiogram).

What are the different types of echocardiography tests?

Transthoracic echocardiography (commonly referred to as TTE) is the most common variety of echocardiography tests. It uses a device called a transducer to send sound waves to your heart via the chest wall. As these waves are reflected by the heart, a computer converts them into images that can be viewed on a screen. In this article, we will be talking about TTE mostly.

Stress echocardiography– It is a type of echocardiography where the heart is made to beat faster and harder by exposing it to stress. The subsequent procedure is the same as TTE. The stress may be in the form of physical activity (running on a treadmill or cycling a stationary bike) or drug-induced.

This technique helps in unmasking diseases of the heart which may not be visible during normal echocardiography (e.g. coronary artery disease).

Transesophageal Echocardiography (TEE)– To visualize the interior of your heart with more clarity, the physician may attach the transducer to the end of a flexible tube and insert it in your throat and into your esophagus (food pipe).

As the ultrasound waves have a lesser distance to travel, the images obtained are of very high quality. Three-dimensional echocardiography- 3-D images with a very high resolution are produced.

Fetal echocardiography– It is performed between 18-22 weeks of pregnancy in order to look for any congenital cardiac defect in the fetus. The transducer is moved over the abdominal region of the pregnant female and the images procured.

Doppler echocardiography– It employs the ‘Doppler phenomenon’ to ascertain the speed and direction of blood flow in the heart and its major blood vessels. It does so by detecting changes in the frequency of the ‘backscatter signal’ from small moving structures.

Can I undergo echocardiography if I am pregnant?

An echocardiography test does not use any radiation. Therefore, it is perfectly safe to undergo echocardiography during pregnancy. In fact, fetal echocardiography is performed to detect congenital heart diseases before birth.

Can children undergo echocardiography test?

Yes. It is safe for children to undergo echocardiography. No radiation is used during this process.

What are the risks involved?

Echocardiography is a non-invasive, painless and safe procedure.

– A dye is used sometimes used in echocardiography in order to visualize the interior of the heart better. An allergic reaction to the dye is rare but at times a serious complication.

– During transesophageal echocardiography you may feel pain, bruising, bleeding and subsequently infection at the site of intravenous access. You may experience soreness in your throat for some time. A sedative is used in TEE in many cases. You may experience side effects related to it.esophageal perforation–1 in 10,000 is another rare complication.

– During stress echocardiography, there is a risk of precipitating an underlying heart disorder. But these risks are related to the stress-inducing exercise/medicine and not directly linked with the procedure.

What are the contra-indications of echocardiography?

There are no absolute contra-indications for echocardiography. However, as per the FDA (US Food and Drug Administration) guidelines, transthoracic echo test should not be performed in the following cases-

– Acute MI (myocardial infarction) or acute coronary syndrome
– Heart failure (worsening or unstable)
– Serious ventricular arrhythmia
– Respiratory failure
– Conditions that may lead to pulmonary hypertension

How should I prepare for echocardiography?

There are no specific precautions required on your part before undergoing am echocardiography test. However, if you are undergoing a TEE, you need to fast for 6-8 hours prior to the test. Moreover, you need to talk to your physician regarding your medical history, past drug history, any medicines that you might be taking and allergies that you suffer from.

It is advisable to remove any precious jewelry before coming to the hospital for the test. Remove any piercings on your chest as these may interfere with the transducer. Males undergoing this procedure are sometimes advised to shave off their chest hair to make it easier for the electrodes to be patched onto the chest and facilitate their removal at the end of the procedure.

Do I need to fast before an echocardiography exam?

There is no need to fast before an echocardiography test. However, if you are supposed to undergo TEE, you need to fast for 6-8 hours prior to the test.

How is an echocardiography test performed?

An echocardiogram is performed on an outpatient basis- either in a hospital or a diagnostic center.

What happens before the echocardiography procedure begins?

Before the procedure-

– Your physician will explain the procedure of echocardiography to you.

– You will be asked to remove your clothes, waist up. If you are a female, you will be given a hospital gown to wear.

How is an echocardiography procedure performed?

– You will be made to lie on an examination table on your side (the left lateral decubitus position is commonly used). You will be asked to place your left arm over your head.

– You may be asked to change positions during the procedure and to hold your breath at times.

– Electrodes (usually 3 in number) will be applied to your chest. These are soft, sticky flat patches that help in recording the electrical activity of your heart in the form of an ECG (electrocardiogram).

– A wand-like an instrument known as the ultrasound transducer will be moved over the area of your chest. A gel is applied both on the wand and your chest to increase the conductibility of the waves.

– You may feel some discomfort when the transducer is pressed firmly against your chest.

– The transducer performs the function of sending ultrasonic waves to your heart.

-As your heart sends echoes of the sound waves, these are detected by the transducer and conveyed to a computer. The computer converts these waves into images that can be stored in the form of discs.

What happens after the procedure is over?

After the procedure-

– There are no specific instructions to be followed once the test is over.

– If you have undergone a transesophageal echo, you will be shifted to a recovery room to recover from the effects of the sedative used.

How long does an echocardiography exam take?

A standard echocardiography test takes about 45-60 minutes to be conducted.

What is the cost of undergoing echocardiography in India?

The cost of undergoing echocardiography in India ranges from INR 1500-5000.

What are the advantages and limitations of an echocardiography test?