Echocardiography

What it is

Echocardiography (“echo” for short) uses high-frequency sound waves to create images of the heart in real time. A small probe, with gel on its tip, is placed on the chest. It uses no radiation, involves no injection and has no side effects.

The most common form, done through the chest wall, is called transthoracic echocardiography. Other forms exist (with a thin tube through the esophagus, or with stress), which are carried out only for special indications in specialized centers.

What it shows

• the size and thickness of the chambers and heart wall
• the pumping strength — the ejection fraction (EF) of the left ventricle
• the valves — whether they are narrowed (stenosis) or leaking (regurgitation)
• fluid around the heart (the pericardium)
• the estimated pressure in the pulmonary artery and the main vessel (the aorta)
• clots or masses inside the heart, when suspected

Echo does not replace the ECG: it does not show the heart rhythm. The ECG and the Holter ECG are separate exams for arrhythmias.

When an echocardiogram is needed

The doctor recommends it when there is a clinical question that echo can answer, for example:

• symptoms: dyspnea, unusual fatigue, swelling of the ankles (edema), palpitations, fainting, chest pain with suspected cardiac cause
• a heart murmur heard on examination
• hypertension with suspected thickening of the wall (left ventricular hypertrophy)
• after a heart attack or when heart failure is suspected
• follow-up of valve disease, e.g. aortic stenosis, at an interval set by the cardiologist
• before and during treatment with drugs that can affect the heart (some chemotherapies and targeted therapies) — to detect any drop in function early
• after a stroke or episodes of atrial fibrillation, when looking for a possible source of clots

Repeating echo “every year” in people with no symptoms and a healthy heart is usually not necessary. When it needs to be repeated, the cardiologist decides according to the diagnosis.

Preparation

• No fasting is needed and medicines are not stopped, unless the doctor tells you otherwise.
• Wear clothes that are easy to remove from the upper body.
• Bring previous exams (ECG, old echoes, discharge letters) — comparison is very helpful.

During the exam

You lie on your left side, with your left arm raised. The doctor places a few small electrodes on the chest (to follow the rhythm during the recording) and moves the probe to several positions. You may hear “whooshing” sounds — these are the sounds of blood flow (Doppler).

It usually takes 20–40 minutes. You may feel light pressure from the probe; it is not painful. In some people the images are less clear (overweight, hyperinflated lungs, changes after surgery) and the doctor takes this into account in the assessment.

Understanding the results

The cardiologist gives a report with the measurements and a conclusion. Some of the terms you will see:

• EF (ejection fraction): what share of the blood in the left ventricle is ejected with each beat. Usually 55% or higher is considered normal; lower values indicate reduced function.
• Dimensions: the size of the chambers and thickness of the wall — compared with norms for sex and body surface area.
• Valves: a “mild leak” (minimal regurgitation) is often seen in healthy people and usually has no clinical significance.

A mild finding in the report does not mean disease. The result is assessed together with symptoms, the ECG and blood tests — not in isolation.

Risks

Transthoracic echo has no known risks and can be repeated as often as needed. There may be mild skin irritation from the gel or electrodes.