01Purpose and principlesWhat the assessment is for and the core concepts behind it.
Echocardiography uses reflected ultrasound to create moving anatomical images and Doppler frequency shifts to estimate the direction and velocity of blood flow. Two-dimensional views show morphology and motion; M-mode offers high temporal resolution; colour Doppler maps flow direction and turbulence; pulsed-wave Doppler samples a chosen site; and continuous-wave Doppler records high velocities along an entire beam. The result is a physiological examination whose accuracy depends on beam alignment, acoustic windows, rhythm and loading conditions.
A standard adult transthoracic echocardiogram is an organised survey rather than a single ejection-fraction measurement. Parasternal, apical, subcostal and suprasternal views cross-check anatomy in different planes. Chamber dimensions and volumes, regional and global ventricular motion, valve structure, transvalvular flow, estimated pressures, the aortic root, inferior vena cava and pericardium are interpreted together. A focused scan answers an urgent narrow question but should not be mistaken for a comprehensive study.
The report should convert images into a clinical explanation: what was seen, how confidently it was measured, what haemodynamic consequence is present, whether the findings explain the presentation, and what further test or urgency follows. Normal findings lower the likelihood of several structural diagnoses, yet do not exclude intermittent arrhythmia, coronary disease without resting dysfunction, early infiltrative disease, pulmonary embolism or acute aortic syndromes.
Key points
- Begin with the clinical question, rhythm, blood pressure, body size and image quality because every measurement needs that context.
- A comprehensive transthoracic study surveys all chambers, valves, great vessels, pericardium and Doppler haemodynamics in linked views.
- Ejection fraction describes chamber volume change; it does not by itself establish stroke volume, filling pressure, myocardial health or cause.
- Grade valve disease by integrating morphology, multiple Doppler measures, chamber response and symptoms rather than one impressive number.
- A technically limited or internally inconsistent examination should be reported as such and escalated to contrast echo, transoesophageal echo, CT or CMR when the answer matters.
- Compare serial studies only after checking acquisition method, loading conditions, rhythm and whether measurements were made at the same anatomical level.
- Unexpected severe findings need direct clinical communication because a report placed silently in the record may not trigger timely care.
02Indications, selection and cautionsWhen it is useful, when urgency changes and important limitations.
Assess cavity size, wall thickness, global systolic function and regional motion. Concentric thickening suggests a pressure-loaded ventricle, whereas dilation with reduced contraction suggests volume overload or myocardial disease; regional abnormalities raise ischaemic or scar-related causes.
Right ventricular enlargement, impaired longitudinal motion, septal flattening and altered pulmonary flow may indicate pulmonary hypertension, pulmonary embolic strain or shunt-related volume loading. Interpretation requires the clinical setting because no single sign proves the cause.
Thickened, restricted or prolapsing leaflets identify mechanism, while jet velocity, gradients, valve area calculations and regurgitant features describe severity. Chamber remodelling and pulmonary pressure provide evidence of chronic consequence. NICE says to offer urgent specialist assessment including echocardiography within 2 weeks for a systolic murmur with exertional syncope; if specialist assessment is unavailable, offer urgent echocardiography alone.
Mitral inflow, tissue Doppler, atrial size and pulmonary pressure are combined to judge relaxation and filling pressure. Age, atrial fibrillation, significant mitral disease and pacing can invalidate simplified algorithms.
Describe effusion size, distribution and haemodynamic effect rather than equating fluid volume with tamponade. Masses, vegetations and thrombi require attention to location, mobility, artefact and the limits of transthoracic resolution.
Poor endocardial definition, foreshortened apical views, off-axis dimensions or misaligned Doppler can create false chamber sizes and gradients. Discordance between data and symptoms is a finding that should prompt review, repeat acquisition or another modality.
03Method and interpretationA systematic approach to the test and its findings.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Comprehensive transthoracic echocardiographyFirst step - Why
- Survey cardiac anatomy, ventricular function, valves, haemodynamics and pericardium non-invasively.
- Interpretation and limitations
- Use multiple orthogonal views and Doppler measurements, state technical quality, and integrate abnormalities rather than accepting a single derived value. For suspected chronic heart failure, an untreated NT-proBNP concentration above 2,000 ng/L requires urgent specialist assessment and transthoracic echocardiography within 2 weeks; 400 to 2,000 ng/L requires specialist assessment and echocardiography within 6 weeks. These bands set referral urgency, not the ventricular phenotype.
- 02
Contrast-enhanced transthoracic echocardiography - Why
- Improve endocardial border definition or answer selected cavity and perfusion questions.
- Interpretation and limitations
- Better opacification can rescue volume and regional-motion assessment, but artefact, shunting and agent-specific precautions still require trained acquisition and reporting.
- 03
Transoesophageal echocardiography - Why
- Resolve structures poorly seen from the chest wall, especially valves, atria and thoracic aorta.
- Interpretation and limitations
- Its proximity improves spatial detail for vegetations, prostheses, atrial appendage thrombus and dissection, while semi-invasive risks and blind regions remain relevant.
- 04
Stress echocardiography - Why
- Reveal inducible wall-motion abnormality, dynamic obstruction or symptom-related valve physiology.
- Interpretation and limitations
- A new or worsening regional abnormality during adequate stress supports inducible ischaemia; inadequate stress or poor images make a negative result less reassuring.
- 05
Cardiac magnetic resonance or cardiac CT - Why
- Provide complementary tissue, volume, coronary, valve or aortic information when echo is incomplete.
- Interpretation and limitations
- Choose the modality for the unresolved question: CMR excels at reproducible volumes and tissue characterisation, while CT gives high-resolution anatomy and calcium detail.
04Clinical next stepsHow the result changes management or prompts escalation.
01Initial studyAnswer the referral question systematicallyFirst stepA patient has symptoms, signs, ECG changes or a murmur suggesting structural heart disease.+
- 1Confirm the clinical question, urgency, rhythm, blood pressure, height and weight before interpreting measurements.
- 2Acquire the comprehensive standard dataset, then add lesion-specific views and Doppler when an abnormality appears.
- 3Integrate morphology, quantitative measures and secondary chamber responses into a graded conclusion with stated limitations.
- 4Communicate immediately when the study reveals a finding that changes same-day management or requires urgent specialist assessment.
02Heart failure pathwayMove from symptoms to cardiac phenotypeBreathlessness, oedema or fatigue and natriuretic peptide results raise suspicion of heart failure.+
- 1Use the recommended referral timeframe and obtain transthoracic echo with specialist assessment rather than labelling heart failure from symptoms alone.
- 2AlternativeAssess left and right ventricular systolic function, diastolic indices, valve disease, shunts and alternative structural explanations.
- 3Describe the phenotype and uncertainty, because treatment decisions depend on more than an isolated ejection fraction.
- 4If image quality is poor or no abnormality explains persistent concern, discuss CMR, transoesophageal echo or another targeted test.
03Valve pathwayResolve a murmur or known valve lesionA murmur, symptoms, abnormal ECG or previous valve disease prompts echocardiographic assessment.+
- 1Define valve anatomy and lesion mechanism, then acquire aligned Doppler data from more than one appropriate window.
- 2Grade severity using concordant parameters and record ventricular, atrial and pulmonary pressure consequences.
- 3Relate findings to symptoms and refer moderate, severe or bicuspid aortic valve disease for specialist assessment as recommended.
- 4Plan surveillance from lesion severity, ventricular response, symptoms and intervention suitability, revisiting earlier if the clinical state changes.
04Discordant studyEscalate when the answer remains uncertainEscalationThe study is technically limited, measurements conflict, or findings do not explain a high-risk presentation.+
- 1Recheck views, Doppler alignment, tracing, rhythm selection and whether loading conditions altered the apparent physiology.
- 2Repeat or enhance transthoracic imaging when a correctable acquisition problem is likely.
- 3Choose transoesophageal echo, CT, CMR or invasive assessment according to the anatomical or physiological uncertainty.
- 4Keep urgent clinical pathways active while additional imaging is arranged when a dangerous diagnosis remains possible.
05Risks, monitoring and follow-upComplications, safety checks and further assessment.
- For asymptomatic severe valve disease when intervention is suitable but not yet needed, NICE advises clinical review with echocardiography every 6 to 12 months, with frequency shaped by findings and shared decisions.
- For mild aortic or mitral stenosis, NICE advises considering echocardiographic reassessment every 3 to 5 years; new symptoms should prompt earlier review.
- In chronic heart failure, repeat imaging when it will answer a new management question, such as clinical deterioration, suspected new valve disease or device planning, rather than by an automatic calendar alone.
- Compare serial chamber and valve measurements using the same method where possible and explain when rhythm, blood pressure or image quality limits apparent change.
- After valve repair or replacement, tailor surveillance to prosthesis or repair durability, residual abnormality, other cardiac disease, symptoms and concern about dysfunction.
- An important unexpected result should be communicated directly and documented, with the requested follow-up test and responsible clinical team made explicit.
06Special situationsVariants, exceptions and circumstances that change the usual approach.
Ejection fraction is load dependent
A preserved percentage can coexist with low stroke volume, severe valve disease or abnormal filling. A reduced value can change with preload, afterload and rhythm, so interpret it with volumes, haemodynamics and context.
Doppler measures velocity, not pressure
Pressure gradients are derived from velocity and depend strongly on beam alignment. Underalignment usually underestimates velocity, while sampling the wrong jet can attribute flow to the wrong lesion.
Regurgitation needs integration
Jet area alone changes with driving pressure, gain and receiving-chamber conditions. Mechanism, vena contracta, flow convergence, pulmonary or venous flow and chamber response provide a more reliable synthesis.
Atrial fibrillation changes measurement strategy
Variable cycle length alters filling and stroke volume. Measurements should use representative beats with attention to preceding intervals rather than averaging visibly non-comparable cycles.
A normal TTE has boundaries
Routine transthoracic images may not exclude small vegetations, left atrial appendage thrombus, early infiltrative disease, coronary stenosis or the full thoracic aorta. Test selection follows the remaining clinical question.
07Common pitfallsFrequent interpretation and management errors.
- 01
Calling the left ventricle normal from ejection fraction alone while ignoring size, wall thickness, regional motion, filling and stroke volume.
- 02
Grading valve disease from one Doppler value without checking alignment, morphology, flow state and concordant chamber consequences.
- 03
Treating a focused bedside scan as a comprehensive exclusion test after the patient has stabilised or the first question changes.
- 04
Reporting estimated pulmonary artery pressure as definitive pulmonary hypertension without considering signal quality and the broader right-heart assessment.
- 05
Comparing serial measurements without noticing that different views, conventions, rhythms or loading conditions created the apparent change.
- 06
Allowing a technically poor negative study to close investigation despite persistent high-risk symptoms or a strong alternative imaging indication.