Skip to textbook content
Doctor’s PassportTextbook
TopicsAll topics

Loading topic navigation…

Textbook navigation
TopicsAll topics

Loading topic navigation…
← Cardiology indexChapter sections
Purpose and principlesIndications, selection and cautionsMethod and interpretationClinical next stepsRisks, monitoring and follow-upSpecial situationsCommon pitfallsQuestionsSources
Full textbook9 sectionsOpen only what you need
Educational draft · awaiting clinical reviewThe full textbook explains uncertainty but does not replace live national or local guidance, specialist advice, or current prescribing information.

Transthoracic and transoesophageal echocardiography

Cardiology · UK scope · Sources checked 27 Aug 2026 · Clinical review pending

RapidFull
!
Time-critical presentation

Use urgent bedside TTE for shock, suspected tamponade or major mechanical complication, but do not let imaging delay immediately necessary resuscitation or reperfusion. Suspected aortic dissection may require TOE or CT according to stability and local expertise.

Purpose and principles

Choose TTE or TOE for the clinical question, recognise urgent findings and interpret measurements in the context of image quality and loading conditions.

Select the modality from the question. TTE is accessible and haemodynamically informative; TOE is preferred when TTE windows are inadequate or detailed views of vegetations, prosthetic valves, left atrial appendage, interatrial septum or thoracic aorta are needed.

A useful report states rhythm, blood pressure when relevant, image quality, chamber size, systolic and diastolic function, regional wall motion, valve morphology and severity, right-heart findings, aorta, pericardium and comparison with prior studies.

Unexpected critical findings require direct clinician-to-clinician communication, not passive report filing.

Key points

  • TTE is first-line for ventricular size and function, valve assessment, pulmonary-pressure estimates and pericardial fluid.
  • TOE places the probe near posterior cardiac structures and gives higher-resolution views of atria, valves and thoracic aorta.
  • A focused bedside echo answers a narrow emergency question; it is not a substitute for a complete accredited study.
  • Ejection fraction is load-dependent and should be integrated with volumes, regional motion and clinical state.
  • Valve severity requires multiple concordant parameters; never grade from colour-jet area alone.
  • TOE is semi-invasive: confirm consent, fasting status, airway and oesophageal risks, sedation plan and monitoring.
  • Negative imaging does not end a high-probability endocarditis or aortic-dissection work-up; repeat or alternative imaging may be required.

Indications, selection and cautions

Tamponade physiologyRed flag

Pericardial effusion with right-sided chamber collapse, marked respiratory inflow variation and a plethoric IVC supports haemodynamic compromise; clinical shock determines urgency.

Post-MI mechanical complicationRed flag

New severe mitral regurgitation, ventricular septal defect or free-wall rupture with instability demands immediate cardiology and surgical escalation.

Severe valve disease

Integrate morphology, velocities, gradients, valve area, regurgitant measures, chamber response and symptoms; discordant data need expert review.

Infective endocarditis

Vegetation, abscess, prosthetic dehiscence or new regurgitation is important, but a negative TTE is insufficient when clinical suspicion remains high.

Right-heart strain

RV dilatation or dysfunction and raised pulmonary-pressure estimates support pressure overload but do not diagnose pulmonary embolism in isolation.

Method and interpretation

  1. 01
    Comprehensive TTEFirst stepFirst line
    Why
    First-line structural and haemodynamic assessment.
    Interpretation and limitations
    Use quantitative multiparametric reporting and state limitations; compare with previous measurements using the same method where possible.
  2. 02
    Focused emergency TTE
    Why
    Rapidly assess ventricular function, major pericardial effusion and gross volume clues in instability.
    Interpretation and limitations
    Treat it as a time-limited question and obtain comprehensive imaging after stabilisation.
  3. 03
    TOE
    Why
    Resolve prosthetic-valve, endocarditis, left atrial appendage, septal or thoracic-aortic questions.
    Interpretation and limitations
    Superior resolution does not remove sampling limitations; repeat imaging when disease evolves and suspicion persists.
  4. 04
    Contrast echocardiography
    Why
    Improve endocardial-border definition or identify selected shunts and masses.
    Interpretation and limitations
    Use an approved agent or agitated saline for the correct indication with trained monitoring; protocols are not interchangeable.
  5. 05
    CMR or cardiac CT
    Why
    Resolve poor acoustic windows, tissue-characterisation questions or anatomy not fully shown by echo.

Clinical next steps

01Preferred routeNew murmur or suspected heart failureFirst stepPreferredSymptoms, signs, ECG or natriuretic peptide suggest structural disease+
  1. 1Request comprehensive TTE with a specific clinical question and relevant prior information.
  2. 2Grade any lesion using multiple measures and relate it to ventricular response and symptoms.
  3. 3Refer moderate or severe valve disease, ventricular dysfunction or pulmonary hypertension through the appropriate specialist pathway.
  4. 4Set surveillance from the lesion and guideline, not an arbitrary annual default.
02AlternativeWhen TOE adds valueAlternativeTTE is non-diagnostic or detailed posterior, prosthetic, embolic-source or aortic imaging is needed+
  1. 1Confirm that TOE will change management and review prior imaging.

Risks, monitoring and follow-up

  • Record heart rate, rhythm and blood pressure when interpreting Doppler measurements.
  • Use lesion-specific echo surveillance intervals and bring review forward for new symptoms.
  • During TOE monitor oxygen saturation, blood pressure, ECG, airway and sedation depth, then use formal recovery criteria.
  • Track ventricular size and function with consistent methods across serial studies.
  • Communicate critical findings directly and document receipt.

Special situations

EF is not contractility

Preload, afterload, valve lesions and geometry can change ejection fraction without a matching change in intrinsic myocardial function.

Low-flow valve states

A low gradient does not exclude severe aortic stenosis when stroke volume is low; reconcile valve area, flow and ventricular function.

TOE sees posterior structures

The left atrial appendage, mitral apparatus and prosthetic valves are common reasons it outperforms transthoracic windows.

Tamponade is clinical

Echo signs support physiology, but drainage decisions depend on haemodynamic compromise, cause and trajectory.

Report the limitation

An explicit 'apex not visualised' is safer than a falsely normal regional-wall-motion statement.

Common pitfalls

  1. 01

    Equating a visually estimated ejection fraction with a precise, load-independent measurement.

  2. 02

    Grading regurgitation from colour area alone.

  3. 03

    Calling endocarditis excluded after one negative TTE in a high-risk presentation.

  4. 04

    Performing sedated TOE without documented airway, oesophageal and recovery assessment.

  5. 05

    Letting a focused bedside scan replace a complete study after stabilisation.

Practice

Two practice questions

Your practice draft is saved in this browser.

Question 1 of 2
0 correct
CardiologyOriginal SBA

Choosing TOE

A patient with a prosthetic mitral valve has persistent bacteraemia and a non-diagnostic TTE. Which test is most appropriate next?

Choose one answer, then submit
← Rapid synopsisBack to overviewAll Cardiology topics →
Sources and review status4 sources · checked 27 Aug 2026 · clinical review pending+
Sources

Sources and review status

National guidance is shown before implementation-dependent detail. Apply principles in context and verify current guidance when a decision affects care. Source check completed 27 Aug 2026; clinical approval remains outstanding.

  • NICE NG106: Chronic heart failure in adults
  • NICE NG208: Heart valve disease presenting in adults
  • ESC 2023 Guidelines for endocarditis
  • ESC/EACVI cardiovascular imaging consensus documents

Editorial contact: Doctor’s Passport editorial team. Source-check date is separate from clinical approval. Report a content problem · Content changes

Authoring stateComplete draftClinical stateAwaiting reviewJurisdictionUnited Kingdom
Interpretation and limitations
Choose the complementary modality based on rhythm, device, renal function, radiation and the clinical question.
2
Screen for swallowing difficulty, oesophageal disease, bleeding risk, dentition, airway and sedation risk; obtain consent.
  • 3Perform with continuous monitoring and a trained recovery pathway.
  • 4Document findings, complications and post-sedation restrictions; arrange complementary CT or CMR if unresolved.
    • 03EscalationUnstable patientEscalationShock, acute pulmonary oedema, new post-MI murmur or suspected tamponade+
    1. 1Resuscitate and obtain immediate expert focused imaging at the bedside where it will change action.
    2. 2EscalationEscalate tamponade or mechanical-complication findings directly to intervention or surgery.
    3. 3If images are inadequate, choose TOE, CT or catheterisation according to the emergency and stability.
    4. 4Repeat a full study after intervention or when haemodynamics change.