Echocardiogram
Also known as: echo, heart ultrasound, transthoracic echo, transoesophageal echo
An ultrasound of the beating heart. It shows the size and thickness of the chambers, how strongly the ventricles pump, whether the valves open and close properly, and the pressures inside, all in real time and without radiation.
- Abbreviations
- TTE, TOE
- Kind
- Imaging study
- Categories
- Cardiovascular, Imaging
- Specimen
- No specimen
- Method
- Ultrasound
- Modality
- Ultrasound
- Type
- Cardiac ultrasound
- Sample
- No sample; a probe with gel on the chest, 20-40 minutes
- Used for
- Heart failure, murmurs and valve disease, after a heart attack, stroke work-up
- Measures
- Heart structure, pumping function, valve function and pressures in real time
- Result
- Measurements (ejection fraction, chamber sizes, wall thickness, valve gradients) with a structured report
Why is it used?
- Breathlessness or raised BNP (heart failure)
- A murmur or suspected valve disease
- After a heart attack
- Atrial fibrillation, stroke (looking for a source of clots)
- Suspected endocarditis, pericardial fluid, congenital heart disease
What does it measure?
| Component | What it measures | A higher value may be seen in | A lower value may be seen in |
|---|---|---|---|
| Left ventricular ejection fraction LVEF | Percentage of blood the left ventricle ejects each beat | Hyperdynamic states (sepsis, anaemia, thyrotoxicosis) | Heart failure with reduced ejection fraction, previous infarction, cardiomyopathy |
| Wall motion | Whether each segment of muscle contracts normally | Not applicable | Regional abnormality: infarction or ischaemia in a coronary territory |
| Chamber size and wall thickness | Dilatation or hypertrophy of the atria and ventricles | Dilated: heart failure, valve leaks, atrial fibrillation; thick walls: hypertension, aortic stenosis, hypertrophic cardiomyopathy | Small chambers: dehydration, restrictive disease |
| Valve function | Narrowing (stenosis) or leaking (regurgitation) of each valve, graded by Doppler | Severe stenosis or regurgitation may need repair or replacement | Not applicable |
| Diastolic function and filling pressures | How the ventricle relaxes and fills | Raised filling pressures: heart failure with preserved ejection fraction, hypertension, older age | Not applicable |
| Pericardium and estimated pulmonary pressure | Fluid around the heart; right-heart pressures | Pericardial effusion; pulmonary hypertension from lung disease, clots or left-heart disease | Not applicable |
A high or low value can be associated with several different situations; the result is interpreted with other results, symptoms, history and clinical findings.
How is it performed?
Lying on the left side, a probe with gel is moved over the chest for 20-40 minutes. A transoesophageal echo passes a probe down the gullet for clearer views, with sedation.
Specimen. None: ultrasound images of the beating heart
Do I need to prepare?
None for the standard test; fasting for the transoesophageal version.
What do the results generally mean?
| Finding | What it may indicate |
|---|---|
| Ejection fraction 30% | Significantly reduced pumping; start heart-failure treatment |
| Severe aortic stenosis | Valve replacement when symptoms appear |
| Regional wall-motion abnormality | Coronary disease with previous infarction |
| Normal study | Heart failure and valve disease effectively excluded |
What can affect the result?
- Image quality: obesity, lung disease and chest-wall shape limit the acoustic window (a transoesophageal echo or contrast may be needed)
- Heart rate and rhythm at the time (atrial fibrillation makes measurements variable)
- Blood pressure and fluid status on the day
- Operator experience and machine settings
Medicines. Heart-failure medicines can improve ejection fraction over months; beta blockers and rate control change measurements in atrial fibrillation; some chemotherapy (anthracyclines, trastuzumab) is monitored with serial echocardiograms.
What can the test not tell you?
- Whether the coronary arteries are narrowed (stress echo, CT or angiography)
- The heart's electrical rhythm over time (ECG and monitoring)
- The cause of breathlessness when the heart is normal
Image quality falls with obesity and lung disease. Coronary arteries themselves are not seen; a stress echo or angiogram is needed for that.
Other tests commonly used with it
Catalogued concepts this page covers
Concepts of the master test taxonomy that resolve to this page; each links to its category.