| Literature DB >> 33112828 |
Shaun Robinson1, Bushra Rana2, David Oxborough3, Rick Steeds4, Mark Monaghan5, Martin Stout6, Keith Pearce6, Allan Harkness7, Liam Ring8, Maria Paton9, Waheed Akhtar10, Radwa Bedair11, Sanjeev Bhattacharyya12, Katherine Collins13, Cheryl Oxley14, Julie Sandoval15, Rebecca Schofield MBChB1, Anjana Siva16, Karen Parker17, James Willis18, Daniel X Augustine18.
Abstract
Since cardiac ultrasound was introduced into medical practice around the middle twentieth century, transthoracic echocardiography has developed to become a highly sophisticated and widely performed cardiac imaging modality in the diagnosis of heart disease. This evolution from an emerging technique with limited application, into a complex modality capable of detailed cardiac assessment has been driven by technological innovations that have both refined 'standard' 2D and Doppler imaging and led to the development of new diagnostic techniques. Accordingly, the adult transthoracic echocardiogram has evolved to become a comprehensive assessment of complex cardiac anatomy, function and haemodynamics. This guideline protocol from the British Society of Echocardiography aims to outline the minimum dataset required to confirm normal cardiac structure and function when performing a comprehensive standard adult echocardiogram and is structured according to the recommended sequence of acquisition. It is recommended that this structured approach to image acquisition and measurement protocol forms the basis of every standard adult transthoracic echocardiogram. However, when pathology is detected and further analysis becomes necessary, views and measurements in addition to the minimum dataset are required and should be taken with reference to the appropriate British Society of Echocardiography imaging protocol. It is anticipated that the recommendations made within this guideline will help standardise the local, regional and national practice of echocardiography, in addition to minimising the inter and intra-observer variation associated with echocardiographic measurement and interpretation.Entities:
Keywords: echocardiography; minimum dataset; transthoracic echocardiography
Year: 2020 PMID: 33112828 PMCID: PMC7923056 DOI: 10.1530/ERP-20-0026
Source DB: PubMed Journal: Echo Res Pract ISSN: 2055-0464
A structured approach to image acquisition and standardised measurement protocol for performing a standard transthoracic echocardiogram.
| View (modality) | Measure | Explanatory note | Image |
|---|---|---|---|
| PLAX (2D) | Parasternal long axis (PLAX) view is optimised to demonstrate the best image available. Increase scan depth to assess for posterior pericardial effusion and/or left pleural effusion. | ||
| PLAX (2D): LV | Scan depth is reduced to maximise the PLAX view with around 1 cm beyond the pericardium remaining within the image. | ||
| Left ventricular (LV) wall thickness and internal diameter measures are performed at end-diastole and end-systole (30). Measurements are made at the same level, perpendicular to the long-axis plane of the LV and immediately below the mitral valve leaflet tips. | |||
| Care should be taken to ensure that the measurement is of compacted myocardium only and that: trabeculation, mitral valve (MV) apparatus, papillary muscle and right ventricle (RV) moderator band/septomarginal trebeculation are avoided. | |||
| When measuring LV wall thickness, focal basal septal hypertrophy can lead to overestimation of LV mass. When present, measure distal (more apical) to the septal bulge. Due to the tethered plane of M-mode imaging, 2D measures are preferred. | |||
| PLAX (2D): LV | Qualitative assessment of radial function and motion of the anterior septum and inferior lateral walls. | ||
| PLAX – LA (2D) (zoom may be used) | LA anterior–posterior linear measure | Measure the left atrium (LA) diameter perpendicular to the aortic root and at the level of the sinus of Valsalva (SoV). Inner edge to inner edge method is used at end-systole (11). | |
| PLAX (2D) | RVOT PLAX | At end-diastole, at a similar level to PSAX right ventricular outflow tract (RVOT) (1) measurement. Adjust depth and focal zone to visualise the RVOT. Ideally should form a perpendicular line from the RVOT wall to the junction between the interventricular septum and aortic valve (32). | |
| PLAX (2D) MV scallops | Demonstrate the anatomy and excursion of both mitral leaflets (anterior leaflet leading to the AV, posterior leaflet extending from the base of the infero-lateral wall), the proximal chordae, subvalvular apparatus and annulus anatomy. Imaging in the standard PLAX plane demonstrates MV scallops A2 and P2 (33). | ||
| Focussed assessment of mitral anatomy and function. | |||
| M-mode can be applied to demonstrate timing and speed of leaflet excursion. | |||
| PLAX (2D/CFD) MV scallops: Tilted view | Visual assessment: Complete MV anatomy | Focussing on the MV while tilting the probe towards the RV inflow view demonstrates scallops A3 and P3 and eventually the Postero-medial commissure. Focussing on the MV while tilting the probe towards the RV outflow view will demonstrate scallops A1 and P1 and eventually the antero-lateral commissure. 2D assessment of leaflet anatomy and motion and CFD assessment of mitral regurgitation (MR) can be performed at all levels (33). | |
| PLAX (CFD) MV | Optimise colour flow Doppler (CFD) settings. Adjust the lateral CFD region of interest (ROI) to include 1 cm of the LV on the left lateral border and the roof of the LA on the right lateral border. The CFD ROI height should not extend beyond the anterior and posterior LA walls (33). Simultaneous MV and AV CFD assessment should | ||
| MV CFD zoom. | |||
| PLAX (2D) AV | Zoom on the AV to demonstrate valve cusps. From parasternal view, two cusps are seen: the right coronary cusp (RCC) is positioned anteriorly and extends from the ventricular septal aspect of AV annulus. However, the more posterior cusp in view may be either the non-coronary (NCC) or the left-coronary (LCC) cusp depending on the degree of beam tilt. | ||
| PLAX AV (CFD) | Assessment AV CFD. The ROI is optimised to include the jet proximal isovelocity surface area (PISA) within the aorta and includes full jet expansion with the LV. | ||
| PLAX (2D) – LVOT/AV Zoom | The zoomed image of the LVOT/AV is optimised to demonstrate the central plane of the LVOT and the insertion points of the right and non-coronary cusps. | ||
| PLAX (2D) Aorta (Ao) zoom | Zoomed view. The BSE recommend the inner-edge to inner-edge method for measuring aortic dimensions. However, it should be clearly documented in the report if an alternative measurement approach has been adopted by the department. | ||
| PLAX RV inflow (2D) | The RV inflow view is optimised by tilting the beam inferiorly until the LV is no longer visualised and the diaphragm and liver are brought into view. When this is achieved, the RV inferior wall is adjacent to the diaphragm/liver (left of the image), with the RV anterior wall opposite (right of the image) (32). | ||
| PLAX RV inflow (CFD) | CFD is placed over the TV to assess for TR (35). | ||
| PLAX RV inflow Continuous wave Doppler (CWD) TV | Peak TR velocity is measured by CWD across the tricuspid valve. | ||
| PLAX RV outflow (2D) | Distal RVOT, pulmonary valve (PV), main pulmonary artery (MPA) | The RVOT view is achieved by tilting the ultrasound beam superiorly from the PLAX view and centralising the RVOT and PV in the image (32). | |
| PLAX RV outflow pulsed wave Doppler (PWD) | RVOT (PWD). | Optional to PSAX. A pulsed wave Doppler measurement is taken after positioning the sample volume just below the pulmonic cusps in the centre of the RVOT. Measurement of PV acceleration time (PAT) is made at end expiration from the onset of flow to peak flow velocity. Heart rates outside of the normal range (<70 or >100 bpm) may reduce accuracy and a correction for HR may be used (RVOT acceleration time (AT) × 75/HR). Low-velocity reject is reduced to demonstrate the on onset of blood-flow within the RVOT. Sweep-speed is set to 100–150 mm/s (35). | |
| PLAX RV outflow (CFD) | RVOT CFD and CW assessment of MPAP | Optional to PSAX. Assess for pulmonary regurgitation (PR) and any abnormal flow (32). | |
| PLAX RV outflow (CWD) | Optional to PSAX. The CW Doppler signal is optimised to demonstrate PV forward flow velocity. | ||
| PSAX outflow (2D) | The PSAX view of the AV is optimised to demonstrate the valve in the centre of the image with a depth set to around 1 cm beyond the LA posterior wall. | ||
| PSAX AV zoom (2D/CFD) | Qualitative assessment of cusp morphology, thickness and excursion are assessed visually. A zoomed image of the valve is recommended. Fine tilting of the probe at this level can reveal the ostia of the right and left coronary arteries in the respective sinus. | ||
| PSAX RVOT (2D) | RVOT1; RVOT2 | Qualitative assessment of RVOT structure and function. Proximal and distal measurements of RVOT diameter are made in the PSAX plane at the level of the AV. Both measures are made at end-diastole by the inner-edge to inner-edge method. | |
| RVOT2 is also measured in diastole, immediately proximal to the PV (32). | |||
| The RVOT view is achieved by centralising the RVOT and PV in the image. The main pulmonary artery (MPA) is seen leading to the pulmonary artery (PA) bifurcation (right PA branch seen on the left and left PA seen on the right branch). MPA dimension is measured in end- diastole halfway between the pulmonary valve and bifurcation of main MPA or at 1 cm above the PV (32 ) – refer to the BSE pulmonary hypertension (PHT) guideline for interpretation in the context of PHT (35). | |||
| PSAX IAS (2D/CFD) | CFD is placed over the IAS to assess for trans-septal flow. A zoomed image is recommended, CFD scale may be reduced to identify patent foramen ovale (PFO) flow. | ||
| PSAX inflow/outflow (2D/CFD/CWD/PWD) | CFD is placed over the TV to assess for tricuspid regurgitation. The image may be tilted to provide optimal Doppler alignment with the TR jet. PWD of RV inflow velocities may be performed for the assessment of RV diastolic function (32). | ||
| PSAX LV: MV level (2D/CFD) | The PSAX imaging plane at the level of the MV is optimised to demonstrate the diastolic excursion of the mitral leaflet tips within the circular LV. Off-axis imaging views results in an oblique cross-section imaging plane and an of the LV. The more longitudinal imaging plane results in the LV appearing more elliptic in shape. | ||
| PSAX LV: MV level (2D) | BAS: Basal antero-septum | ||
| PSAX Mid LV: (2D/CFM/MM) | The PSAX view of the LV is taken at the level of the mid papillary muscle. The image is optimised to gain an on-axis cross-sectional view of the circular LV with the mid-apical portion of the crescentic RV seen anteriorly and to the left of the image. Both regional and global left ventricular systolic function is assessed visually. | ||
| PSAX Apical LV: (2D/CFD) | Tilt the beam further inferiorly until the RV apex is no longer in view. | ||
| PSAX (CFD) | Sweep beam from base to apex. | ||
| PSAX (CFD) | Ventricular septal defect (VSD): congenital/post infarct. | ||
| A4C (2D) | Optimize image so that all four chambers are seen. LV apex is positioned at the top and centre of sector. | ||
| A4C (2D) | RV/LV basal diameter ratio | RV/LV basal diameter ratio: Measured from the standard A4C without foreshortening at end diastole. Ratio > 1 suggests RV dilatation (32). | |
| A4C LV (2D) | It is recommended that a template for reporting is based on a 16-segment model. The 17-segment model which includes the LV apex is less commonly applied since the apex is stationary in the true long axis and therefore wall motion is less applicable (37). | ||
| A4C LV Zoom (2D) | LV volumes should be obtained using 2D imaging from A4C and A2C (11). | ||
| A4C (2D GLS) | Measures of GLS. When image quality permits, peak GLS should be performed in all cardio-oncology patients | The average peak global longitudinal strain (GLS) is calculated using the apical long axis (A3C), four chamber A4C and two chamber A2C standard views, respectively. High quality image acquisition, maintaining a frame rate of 40–90 frames/s at a stable heart rate is key. Higher frame rates are required if tracking at faster rates such as during exercise or pharmacological stress tests (38). ECG trigger should be checked. Valve timings should be determined by Doppler to ensure consistency across triplane images. Clear endocardial and epicardial definition (seen throughout the cardiac cycle) is required to ensure adequate segmental tracking during systole and diastole. Markers are placed in each of the respective basal and apical regions, utilising automated tracking where possible to maintain reproducible results. ROI should be manipulated as required to fit the myocardium. Automated tracking should also be combined with a visual assessment of tracking in each view across the whole region of interest including the endocardial and epicardial border (38). If more than two segments in any one view are not adequately tracked, the calculation of GLS should be avoided (38). Furthermore, any segment which is not tracked correctly on visual assessment should be excluded from the final analysis in order not to affect the GLS value. | |
| A4C LA (2D) | Biplane LA volume should be estimated using 2D imaging from the A4C and A2C views. As the long-axis dimensions of the LV and LA lie in different imaging planes, the standard apical views optimised for LV assessment do not demonstrate the maximal LA volume. The A4C and A2C images acquired for LA measurement should be optimised to demonstrate the maximal LA length and volume at end-systole. Measurement is made using Simpson’s biplane method. The A4C and A2C long-axis dimensions should measure within 5 mm of each other. If the difference between measures exceeds 5 mm, the apical views should be reviewed and optimised for LA measurement (11). | ||
| Estimates of LA volume by Area–Length (A–L) method are routinely larger than the same measure made by Simpson’s technique. The A–L method is therefore not interchangeable or comparable with measures made Simpson’s method. As the Simpsons biplane method involves fewer assumptions of LA geometry, it is the recommended method of LA volume measurement (11). | |||
| A4/2/3C MV (2D) | Assess anatomy and excursion of both mitral leaflets (anterior closer to septum; posterior leaflet closer to lateral wall). Segments usually imaged are viewed would be: | ||
| A4C MV (CFD) | MV CFD inflow. Look for abnormal, turbulent or regurgitant flow. | ||
| A4C MV (PWD) | Place sample volume (1–3 mm) at level of the MV leaflet tips in diastole. | ||
| A4C LV tissue Doppler imaging (TDI): | Place sample volume (5–10 mm) at or within 1cm of the insertion of the mitral valve leaflets. The angle of insonation should be as close to parallel as possible. Measure at end expiration. Optimise scale and sweep speed (100 mm/s). | ||
| A4C MV (CWD) | For a qualitative assessment of MR, align CW Doppler through the centre of the regurgitant jet. A faint CW Doppler signal is suggestive of trace-mild MR; CW signal density increases as MR becomes more severe (33). | ||
| A4C PulV (CFD) | Pulmonary vein (PulV) identification | Pulmonary vein identification. | |
| A5C (2D/LVOT CFM) | Assess for laminar or turbulent flow in systole and for regurgitant flow during diastole. When utilising CFD to identify the correct position of PW sample for LVOT Doppler, position the CFD ROI over the LVOT and AV with the lateral borders extending just beyond the LVOT walls. When assessing AR, adjust the colour box width and length to display both the whole length of the jet within the LV and LVOT. The CFD ROI size is optimised to demonstrate the whole jet but maintain frame-rates. Sweep the transducer through multiple views to identify the maximum jet size. Scanning outside of the standard imaging planes is necessary to assess eccentric jets. | ||
| A5C AV (CWD) | CWD. Adjust the angle of the image to achieve parallel alignment with LVOT outflow. | ||
| A5C LVOT (PWD) | PWD – A3C or A5C view. | ||
| Modified A4C RV/RA (2D) | Obtain RV focussed view. From A4C view slide and/or angulate the tail of the transducer along the horizontal plane to place the RV in the centre of the image (instead of the conventional left heart-centred image) whilst ensuring that the LV outflow tract does not come into view. This allows the RV free wall to be clearly seen. Next, rotate the transducer to obtain the maximum diameter (32). | ||
| Modified A4C RV/RA (2D) | As RV size may be underestimated due to the crescentic RV geometry, all RV dimensions should be measured at end-diastole in the focussed RV view. From the A4C view, the RV focussed view is achieved by: | ||
| Modified A4C RV/RA (2D) | RA area is measured in the RV focussed view at the end of ventricular systole on the frame just prior to TV opening. | ||
| Modified A4C (2D/CFD/CWD) TV | Assessment of TR severity. | ||
| TR Vmax is measured by CWD across the tricuspid valve. Multiple views may need to be taken to obtain the optimal window. These include the RV inflow, PSAX, A4C and subcostal views, or a modified view between the PSAX and A4C. | |||
| A4C RV TV (PWD) | TV E wave velocity | The view should be optimised in order to align the ultrasound beam with tricuspid inflow. This may require an unconventional/oblique angulation. | |
| A4C RV fractional area change (FAC) (2D) | Manual tracing of the RV endocardial border, from the lateral tricuspid annulus along the lateral wall to the apex, and back along the interventricular septum to the medial tricuspid valve annulus. Repeated at end-diastole and end-systole. A disadvantage of this measure is that it neglects the contribution of the RV outflow tract to overall systolic function (35). | ||
| A4C Lat TV/MV annulus (MM) | Align the M-mode cursor along the direction of the lateral tricuspid or mitral annulus to maximise longitudinal motion of the annulus. Measurement accuracy is improved by zooming on the TV annulus and selecting a high sweep speed. | ||
| A4C | PW tissue Doppler S wave measurement taken at the lateral tricuspid annulus in systole. It is important to ensure the basal RV free wall segment and the lateral tricuspid annulus are aligned with the Doppler cursor to avoid velocity underestimation (13). | ||
| A2C (2D) | BI: Basal inferior | ||
| A2C (2D/CFD/PWD/CWD) | LV volumes/LA volume as for A4C view | ||
| A2C (2D GLS) | A2C GLS | GLS measurement. See A4C (2D GLS) | |
| A3C (2D) | BIL: Basal infero-lateral | ||
| A3C (CFD/CWD/PWD) | If suboptimal from A5C: | Visual assessment of LVOT, LV inflow, MV, look for abnormal colour flow. and AV. Zoom on MV if anatomy is abnormal | |
| A3C (2D GLS) | A3C GLS | GLS measurement. See A4C (2D GLS) | |
| SC4C (2D) | Four chamber structures, atrial septum | ||
| SC4C (CFD) | Atrial septum | ||
| SC (2D) | IVC diameter is measured perpendicular to the IVC long axis, 1–2 cm from the RA junction at end-expiration. | ||
| SC (MM) | IVC diameter > 21 mm with decreased inspiratory collapse (<50% with a sniff, or <20% with quiet respiration) is considered abnormal and suggestive of raised RAP (35). | ||
| SCSAX (2D) | SAX structures | ||
| SC (2D) | Abdominal aorta (modified view) | ||
| SSN (2D) | Ascending aorta, transverse aortic arch, descending aorta, RPA. Look for abnormal colour flow | ||
| SSN (CFD) | Ascending aorta, transverse aortic arch, descending aorta, right pulmonary artery (RPA). Look for abnormal colour flow. | ||
| SSN (CWD) | Descending aorta peak flow velocity |
| 1. Views to be obtained: | |
| PLAX | Parasternal long axis |
| PLAX | Tilted RV inflow |
| PLAX | Tilted RV outflow |
| PSAX | Parasternal short axis: AV, MV, LV: base, mid, apex |
| PSAX | RV inflow |
| PSAX | RV outflow |
| A4C | Apical four chamber |
| A5C | Apical five chamber |
| A4C | Modified A4C for RV |
| A4C | Optimised for LA volume measure |
| A2C | Apical two chamber |
| A2C | Optimised for LA volume measure |
| A3C | Apical three chamber |
| SC | Subcostal |
| Subcostal | cardiac chambers and IAS |
| Subcostal | IVC, heptic vein and abdominal Ao |
| SSN | Suprasternal |
| LVID d/s | Left ventricular internal dimension in diastole and systole |
| IVSd | Interventricular septal width in diastole |
| LVPWd | Left ventricular posterior wall width in diastole |
| LV Mass | Left ventricular mass |
| LA | Left atrial dimension in PLAX |
| LVOTd | Left ventricular outflow tract diameter |
| Ao sinus | Sinus of Valsalva |
| Ao STJ | Sinotubular junction |
| Prox Asc Ao | Proximal ascending aorta |
| TR Vmax | Tricuspid regurgitation maximal velocity |
| LVEDvol d/s | Left ventricular end-diastolic and systolic volume (biplane/3D) |
| LVEF | Left ventricular ejection fraction |
| LA volume | Left atrial volume at end-ventricular systole (area-length/biplane) |
| TAPSE | Tricuspid annular plane systolic excursion |
| Mitral E/A | Mitral valve maximal velocity early and atrial filling ratio |
| e′ | Lateral and/or septal early myocardial relaxation velocity |
| AV Doppler trace | Maximal aortic velocity, peak/mean pressure gradient and VTI on CW |
| LVOT Doppler trace | LVOT VTI |
| RV | Right ventricular linear dimensions in diastole |
| IVC dimensions | Estimation of RA pressure |
| 2D | Two-dimensional |
| 3D | Three-dimensional |
| A-L | Area length |
| A2C | Apical two chamber view |
| A3C | Apical three chamber view |
| A4C | Apical four chamber view |
| A5C | Apical five chamber |
| AA | Apical anterior |
| AC | Apical cap |
| AF | Atrial fibrillation |
| AI | Apical inferior |
| AL | Apical lateral |
| A | Mitral valve pulse waved Doppler – peak late diastolic wave velocity |
| Ao | Aorta |
| AR | Aortic regurgitation |
| AS | Apical septum |
| AT | Acceleration time |
| AV | Aortic valve |
| BA | Basal anterior |
| BAL | Basal anterolateral |
| BAS | Basal anteroseptum |
| BI | Basal inferior |
| BIL | Basal inferolateral |
| BIS | Basal inferoseptum |
| BP | Blood pressure |
| BPM | Beats per minute |
| BSA | Body surface area |
| BSE | British Society of Echocardiography |
| CFD | Colour flow Doppler |
| cm | Centimetre |
| cm/s | Centimetres per second |
| CO | Cardiac output |
| CS | Coronary sinus |
| CWD | Continuous wave Doppler |
| DR | Dynamic range |
| DT | Deceleration time |
| E | Mitral valve pulse waved Doppler – peak early diastolic wave velocity |
| e′ | Mitral valve tissue Doppler – peak early diastolic wave velocity |
| ECG | Electrocardiogram |
| Emax | Peak velocity in early diastole |
| f/s or FPS | Frames per second |
| FAC | Fractional area change |
| FEEL | Focused Echocardiography in Emergency Life support |
| FICE | Focused Intensive Care Echocardiography |
| FR | Frame-rate |
| GLS | Global longitudinal strain |
| HF | Heart failure |
| HR | Heart rate |
| HV | Hepatic vein |
| IAS | Inter atrial septum |
| IVC | Inferior vena cava |
| IVSd | Interventricular septum diameter end diastole |
| LA | Left atrium |
| LAA | Left atrial appendage |
| LUPV | Left upper pulmonary vein |
| LV | Left ventricle |
| LVEDd | Left ventricular end diastolic diameter |
| LVEF | Left ventricular ejection fraction |
| LVESd | Left ventricular end-systolic diameter |
| LVOT | Left ventricular outflow tract |
| LVPWd | Left ventricular posterior wall diameter end diastole |
| MA | Mid anterior |
| MAPSE | Mitral annular plane systolic excursion |
| MAS | Mid anteroseptum |
| MI | Mid inferior |
| MIL | Mid inferolateral |
| MM | M-mode |
| MPAP | Mean pulmonary artery pressure |
| MR | Mitral regurgitation |
| ms | Milliseconds |
| MS | Mitral stenosis |
| MV | Mitral valve |
| NCC | Non coronary cusp |
| PA | Pulmonary artery |
| PAT | Pulmonary acceleration time |
| PFO | Patent foramen ovale |
| PHT | Pressure half time |
| PLAX | Parasternal long axis |
| PR | Pulmonary regurgitation |
| PSAX | Parasternal short axis |
| PulV | Pulmonary vein |
| PulV Ar dur | Duration of flow reversal within the pulmonary vein during atrial systole (ms) |
| PulV Ar-A dur | Duration of transmitral A wave substracted from Pulv Ar duration (ms) |
| PulV D | Peak pulmonary vein velocity in early LV diastole (after T wave) |
| PulV S | Peak pulmonary vein velocity in early LV systole (after QRS) |
| PV | Pulmonary valve |
| PWD | Pulsed wave Doppler |
| RA | Right atrium |
| RAA | Right atrial area |
| RCC | Right coronary cusp |
| ROI | Region of interest |
| RPA | Right pulmonary artery |
| RUPV | Right upper pulmonary vein |
| RV | Right ventricle |
| RVD1 | Basal RV diameter |
| RVD2 | Mid RV diameter |
| RVD3 | RV length |
| RVOT | Right ventricular outflow tract |
| RVOT1 | Proximal right ventricular outflow tract |
| RWM | Regional wall motion |
| S′ | Tissue Doppler peak systolic velocity |
| STJ | Sinotubular junction |
| SoV | Sinus of Valsalva |
| SV | Stroke volume |
| TAPSE | Tricuspid annular plane systolic excursion |
| TDI | Tissue Doppler imaging |
| TGC | Time-Gain compensation |
| TRVmax | Tricuspid regurgitation peak velocity |
| TTE | Transthoracic echocardiogram |
| TV | Tricuspid valve |
| Vmax | Peak velocity |
| Vmean | Mean velocity |
| VP | Propagation velocity |
| VSD | Ventricular septal defect |
| VTI | Velocity time integral |