An echocardiogram — often called an 'echo' — is an ultrasound scan of the heart. Unlike an ECG, which records electrical signals, an echo produces real-time images of the heart walls, valves and chambers. It's one of the most informative non-invasive cardiac tests available, and the report it generates is packed with measurements that can feel impenetrable to a non-specialist.
This guide breaks down the key numbers so you can have a more informed conversation with your cardiologist.
Ejection fraction: the most important number
The ejection fraction (EF) is the percentage of blood pumped out of the left ventricle with each heartbeat. A normal EF is 55–70%. An EF below 40% indicates reduced pumping function (heart failure with reduced ejection fraction). Values between 40–55% are considered mildly reduced.
An EF above 75% can sometimes indicate a stiff, over-contracted heart — a condition called hypertrophic cardiomyopathy — so an unusually high EF is not automatically reassuring.
"Ejection fraction is a snapshot, not the whole picture — your cardiologist will interpret it alongside symptoms and other measurements."
Dr. Lina Haddad, CMO, Looms
Other key measurements
- Left ventricular dimensions — the size of the heart's main pumping chamber; enlarged chambers can indicate chronic overload
- Wall motion — assesses whether all parts of the heart wall contract normally; abnormal areas may indicate previous heart attacks
- Valvular function — graded mild/moderate/severe; stenosis (narrowing) and regurgitation (leakage) are both assessed
- Diastolic function — how well the heart relaxes to fill with blood between beats; impaired diastolic function can cause breathlessness even with a normal EF
- Pericardial effusion — fluid around the heart; small amounts are often incidental, large amounts require urgent attention
What 'normal variant' and 'incidental finding' mean
Echo reports frequently mention findings that look unusual but are clinically insignificant. A small pericardial effusion, mild tricuspid regurgitation or a mildly elevated gradient across the aortic valve in an otherwise healthy person may all be documented without requiring any action. Your cardiologist will distinguish between these normal variants and findings that warrant follow-up.
If something concerns you, ask directly: 'Does this finding require treatment or monitoring, or is it something to note and leave?' That question almost always gets a clear answer.