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Basic TTE

4 acoustic windows · 11 views · step by step

Basic TEE

Oesophageal & transgastric views · step by step

Measurement guide

16 measurements step by step with images

Reference

LV

Diastole

RV

Valves

Pericardium

Aorta

Normal values — Adult echocardiography

LV dimensions

LV EDD	42–58 mm (M) / 38–52 mm (F)
LV ESD	25–40 mm
IVS (diastole)	6–10 mm
PW (diastole)	6–10 mm
Indexed EDV	<97 mL/m² M / <76 F
Indexed LV mass	<115 g/m² M / <95 F

LV systolic function

Normal LVEF	>52% M / >54% F
Mildly reduced	41–51%
Mod. reduced	30–40%
Severely reduced	<30%
MAPSE	>8 mm
Lateral S' TDI	>7 cm/s

LVH — IVS or PW > 12 mm

HCM: IVS >15 mm asymmetric, mitral SAM, intra-LV gradient >30 mmHg. Concentric if HTN/AS.

Mitral Doppler

E wave	50–100 cm/s
A wave	30–80 cm/s
E/A	0.8–1.5
Deceleration time	150–220 ms
Septal e'	>7 cm/s
Lateral e'	>10 cm/s
Mean E/e' <8	Normal FP
Mean E/e' 9–14	Grey zone
Mean E/e' ≥15	Elevated FP
Indexed LA vol.	<34 mL/m²

Grade	Criteria	Filling P.
I	E/A <0.8 + DT >200 + e' <7	Normal
II	E/A 0.8–1.5 + E/e' 9–15	Elevated
III	E/A >1.5 + DT <150 + E/e' >15	Very high

3/4 criteria rule (ASE 2016)

Elevated FP if ≥2: septal e' <7 · mean E/e' >14 · peak TR vel >2.8 m/s · LA vol >34 mL/m²

Left Atrium Volume

Normal	<34 mL/m²
Mildly enlarged	34–41 mL/m²
Mod. enlarged	42–48 mL/m²
Severely enlarged	>48 mL/m²

RV dimensions & function

Basal diameter	<41 mm
TAPSE	≥17 mm
Tricuspid S' TDI	≥10 cm/s
FAC	>35%
RV/LV ratio	<0.6
RV free wall	<5 mm

Pulmonary pressures

Peak TR vel <2.8	PH unlikely
Peak TR 2.8–3.4	PH probable
Peak TR >3.4	PH likely
SPAP = 4×(Vmax)²+RAP
IVC <21mm + collapse >50%	RAP ≈3 mmHg

Acute Cor Pulmonale (PE)

RV/LV >0.6 · TAPSE <17 · McConnell sign · Paradoxical septum · Peak TR >2.8 · Dilated IVC · RV/RA thrombus

Inferior Vena Cava (IVC)

Normal IVC	<21 mm + collapse >50%
IVC <21mm, collapse >50%	RAP ≈ 3 mmHg
IVC <21mm, collapse <50%	RAP ≈ 8 mmHg
IVC >21mm, collapse <50%	RAP ≈ 15 mmHg
Collapsibility >50% (SB)	Fluid responder

Aortic Stenosis

Parameter	Mild	Mod.	Severe
Vmax (m/s)	2–3	3–4	>4
Mean grad.	<25	25–40	>40
AVA (cm²)	>1.5	1.0–1.5	<1.0
Indexed AVA	—	—	<0.6 cm²/m²
VTI ratio	>0.50	0.25–0.50	<0.25

Low-gradient AS (paradoxical)

AVA <1 cm² BUT mean gradient <40 mmHg. Preserved or low-flow EF. Confirm: dobutamine stress echo or CT calcium score.

Aortic Regurgitation

Parameter	Mild	Mod.	Severe
AR jet / LVOT	<25%	25–65%	>65%
Vena contracta	<3 mm	3–6 mm	>6 mm
Regurg. vol.	<30 mL	30–59 mL	>60 mL
Regurg. frac.	<30%	30–49%	>50%
PHT	>500 ms	200–500 ms	<200 ms
Desc. Ao backflow	Absent	Early	Holodiastolic

Mitral Stenosis

Parameter	Mild	Mod.	Severe
MVA (cm²)	>1.5	1.0–1.5	<1.0
Mean gradient	<5 mmHg	5–10 mmHg	>10 mmHg
PHT	<100 ms	100–220 ms	>220 ms
SPAP	<30 mmHg	30–50 mmHg	>50 mmHg

Mitral Regurgitation

Parameter	Mild	Mod.	Severe
Vena contracta	<3 mm	3–7 mm	>7 mm
ERO / PISA	<0.20 cm²	0.20–0.39	≥0.40 cm²
Regurg. vol.	<30 mL	30–59 mL	≥60 mL
Regurg. frac.	<30%	30–49%	≥50%

Surgical thresholds severe MR (ESC 2021)

Symptomatic: LVEF <60% or ESD >45 mm · Asymptomatic: ESD >40 mm, new AF, SPAP >50 mmHg

Pericardial effusion

Small	<10 mm
Moderate	10–20 mm
Large	>20 mm

Tamponade

RA systolic collapse · RV diastolic collapse · IVC >21mm non-collapsible · Resp. variation mitral flow >25% · Swinging heart

Constrictive pericarditis

Septal e' > lateral e' (annulus reversus) · Inspiratory septal bounce · Dilated IVC · TDI e' preserved (>7) vs restrictive CMP

Normal aortic dimensions

Aortic annulus	18–25 mm
Sinus of Valsalva	29–45 mm M / 26–39 F
Sinotubular junct.	<36 mm M / <32 F
Ascending aorta	<40 mm (<21 mm/m²)
Desc. aorta	<30 mm

Surgical thresholds (ESC 2024)

Ascending Ao >55 mm · >50 mm if bicuspid or Marfan · >45 mm if Marfan + risk factors

Echocardiographic views — TTE and TEE

View examples coming soon

Reference images for each view will be added soon.

Parasternal window

Long axis (PLAX)	LV, LVOT, AoV, MV
Short axis base	AoV, PA, RA, LA, RV
Short axis mitral	Mitral valve
Short axis mid	LV wall motion, IVS

Apical window

4-chamber (A4C)	LV, RV, LA, RA, AV valves
5-chamber (A5C)	+ LVOT, AoV, VTI
2-chamber (A2C)	LV, LA, MV
3-chamber (A3C)	LV, LVOT, AoV

Subcostal window

SC 4-chamber	Pericardium, RV, septum
IVC + hepatics	Diameter, collapsibility
Abdominal aorta	Aneurysm, dissection

Key measurements

Biplane Simpson EF	A4C + A2C
LVOT VTI	A5C, pulsed Doppler
Mitral E/A + TDI	A4C
TAPSE	A4C, M-mode
Peak TR + SPAP	A4C or parasternal
VCI / IVC	Subcostal

View examples coming soon

TEE reference view images will be added soon.

Oesophageal views (30–40 cm)

4-chamber (0°)	LV, RV, LA, RA
2-chamber (90°)	LV, LA, MV
Long axis (120–135°)	LV, LVOT, AoV
AoV short axis	Tricuspid AoV
SVC (90°)	Preload, collapsibility

Transgastric views (40–45 cm)

LV short axis (0°)	LV wall motion
TG long axis	LVOT, VTI, CO

ICU TEE indications

Undifferentiated shock	Poor TTE window
Aortic dissection	Diagnostic emergency
Endocarditis	Vegetations, abscess
LA appendage thrombus	Before cardioversion

Practical TTE tips

Left lateral decubitus → better apical window · Held expiration → parasternal · A4C: probe toward right shoulder · Subcostal: probe flat, end-expiratory apnoea

Common beginner pitfalls

Do not confuse RV (triangular, right of screen) and LV in A4C · Apex must be at image centre · Always check probe orientation

TEE landmarks — depth

25–30 cm	Descending aorta
30–35 cm	Base, AoV, atria
35–40 cm	4-chamber, AV valves
40–45 cm	Transgastric (ant. flex.)

Fluid responsiveness — Indices and protocols

When to assess fluid responsiveness?

Before any fluid challenge in shock. The goal is to predict whether cardiac output will increase by ≥10% after 500 mL crystalloid.

Dynamic indices — spontaneous breathing (SB)

PLR + LVOT VTI	↑ ≥10% = responder
IVC inspi (SB)	↓ >18% = responder
CO = VTI × HR	↑ ≥10% = responder

Dynamic indices — controlled ventilation (CMV)

PPV (CMV)	>13% = responder
SVV (CMV)	>10–12% = responder
SVC collapsibility (TEE)	>36% = responder

Condition	Preferred method
SB, sinus rhythm	PLR + VTI or IVC
CMV, Vt ≥8 mL/kg	PPV, SVV
CMV, intubated, TEE	SVC >36%
AF, low Vt, PAH	PLR + VTI (avg 5 cycles)

Contraindications & limitations

PLR: raised ICP, lower limb fracture, tamponade · PPV/SVV: AF, Vt <8mL/kg, severe PAH, spontaneous breaths · Severe RV failure: no parameter reliable

1

PLR Protocol

1. Semi-recumbent 45° — measure baseline VTI · 2. Passive tilt to supine, legs at 45° · 3. Measure VTI within 60 seconds · 4. Interpret: ↑ ≥10% = responder

Baseline LVOT VTI (cm)

Post-PLR LVOT VTI (cm)

2

Guided timer

Waiting

1:00

1

SVC collapsibility (TEE — Gold standard CMV)

High oesophageal view 90°. Measure max (expiration) and min (inspiration) diameter. Formula: (Dmax − Dmin) / Dmax × 100. Threshold >36% = responder.

SVC Dmax — expiration (mm)

SVC Dmin — inspiration (mm)

2

IVC collapsibility (TTE — Spontaneous breathing)

Subcostal view. Measure Dmax (expiration) and Dmin (inspiration). CI = (Dmax − Dmin) / Dmax × 100. Threshold >50% (SB) = fluid responder.

IVC Dmax — expiration (mm)

IVC Dmin — inspiration (mm)

Generate an echocardiographic report

1

Examination (anonymous)

Anonymous report — no identifying data

Exam date

Indication

Rhythm

HR (bpm)

Quality

Sex

2

Left ventricle

EDD (mm) N:42–58M

ESD (mm) N:25–40

IVS (mm) N:6–10

PW (mm) N:6–10

LVEF (%) N:>52M

EF method

MAPSE (mm) N:>8

Lateral S' N:>7

Segmental wall motion

LV comment

LV outflow tract obstruction (LVOTO)

Intraventricular gradient (mmHg)

Significant if ≥30 mmHg at rest · Severe if ≥50 mmHg

3

Cardiac output

CO = LVOT VTI × π × (LVOT D/2)² × HR | Normal: 4–8 L/min

LVOT VTI (cm)

LVOT diam. (mm) N:18–25

HR for CO calculation (bpm)

4

Diastolic function

E wave (cm/s)

A wave (cm/s)

E/A

DT (ms)

Septal e' N:>7

Lateral e' N:>10

Mean E/e' N:<8

LA vol. (mL/m²) N:<34

Diastolic dysfunction grade

Diastole comment

5

RV & Pulmonary pressures

RV basal diam. N:<41

TAPSE (mm) N:≥17

Tricuspid S' N:≥10

FAC (%) N:>35

Peak TR vel. N:<2.8

Est. SPAP (mmHg)

IVC (mm) N:<21

IVC collapsibility

Acute cor pulmonale / PE signs

McConnell sign Paradoxical septum RV/RA thrombus RV > LV

6

Valves

Mitral valve

Morphology

MR / IM

Aortic valve

Ao Vmax (m/s)

Mean gradient (mmHg)

AVA (cm²)

AI / AR

IT / TR

7

Pericardium & Aorta

Pericardial effusion

Tamponade

Ascending Ao (mm) N:<40

Sinus Valsalva (mm)

Notable findings

Vegetation ASD / shunt Thrombus Mass / tumour

Comment

8

Conclusion

Generated report

—

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Basic TTE

Select an acoustic window:

Left parasternal

3 views

Apical

4 views

Subcostal

4 views

Suprasternal

2 views

Basic TEE

Select a TEE window:

Oesophageal views

30–40 cm — 4 views

Transgastric views

40–45 cm — 4 views

Doppler method — LVOT

LVOT measurements

LVOT diameter (mm)

LVOT VTI (cm)

HR (bpm)

Patient (optional — for CI and SVR)

Weight (kg)

Height (cm)

MAP (mmHg)

RAP (mmHg)

Echocardiographic + clinical criteria

1

Ventilatory mode

Patient ventilatory mode

2

Pericardial effusion

Effusion size

3

Echocardiographic compression signs

These criteria remain valid under mechanical ventilation.

4

Respiratory variations (Doppler)

On spontaneous inspiration: ↑ tricuspid, ↓ mitral. Mitral >25%, tricuspid >40%.

Mitral flow variation >25% Tricuspid flow variation >40% No significant variation

5

Clinical context

Measurement guide

🔍

About SONIC

SONIC

SONography In Critical care

Authors

Clément Brault Médecine Intensive — Réanimation
Valentin Dambrine Médecine Intensive — Réanimation
Yoann Zerbib Médecine Intensive — Réanimation

Affiliation

CHU Amiens-Picardie
Amiens, France

Application

Version	1.0
Standards	ASE / ESC 2022
Usage	Decision support

Disclaimer

This application is a clinical decision support tool. It does not replace the clinical judgment of the practitioner or the recommendations of learned societies.

ASE 2025 Algorithm — Sinus rhythm

Conditions of use — ASE 2025

This algorithm applies only in sinus rhythm. Check applicable conditions:

AF / arrhythmia Severe mitral valve disease LVAD Heart transplant

Mitral inflow (pulsed-wave Doppler) — E and A

E wave = early rapid LV filling · A wave = atrial contraction · DT (E-wave deceleration time) = time from the E-wave peak to its return to baseline, reflects LV compliance. Apical 4-chamber view, pulsed-wave Doppler, sample volume between the mitral leaflet tips. Leave A empty if AF.

E wave (cm/s)

A wave (cm/s)

DT — E-wave deceleration time (ms, optional)

<150 ms = restrictive · >200 ms = impaired relaxation

2

Mitral tissue Doppler (e')

e' = mitral annular early diastolic velocity (tissue Doppler), reflects myocardial relaxation. Apical 4C view, septal then lateral mitral annulus. Mean E/e' = E / [(septal e' + lateral e')/2].

Septal e' (cm/s)

Lateral e' (cm/s)

Thresholds depend on age — set the age group in step 3.

3

Pulmonary vein flow, LAVi and peak TR velocity

S/D = systolic/diastolic pulmonary vein flow ratio (pulsed-wave Doppler A4C, right upper pulm. vein). S/D <1 = elevated pressure. Peak TR velocity = continuous-wave Doppler → SPAP. LAVi = indexed LA volume, biplane Simpson A4C+A2C.

Age group (e' thresholds)

Pulm. vein S wave (cm/s)

Pulm. vein D wave (cm/s)

Peak TR vel. (m/s)

≥2.8 m/s = elevated pressure

LAVi (mL/m²)

>34 mL/m² = dilated LA

LARS — LA reservoir strain (%, optional)

≤18% = elevated pressure

Fluid responsiveness indices with automatic calculations

1

PLR — Passive leg raising VS & VC

Measure LVOT VTI in A5C before and 60s after passive leg raise to 45°

Baseline LVOT VTI (cm)

Post-PLR LVOT VTI (cm)

↑ ≥10% = répondeur

2

ΔLVOT VTI — Respiratory variation VC

Formula: (VTImax − VTImin) / [(VTImax+VTImin)/2] × 100 · Valid if Vt ≥8 mL/kg · sinus rhythm

VTI max — inspi (cm)

VTI min — expi (cm)

≥12–14% = répondeur

3

SVC — Collapsibility (TEE) CMV · gold std

High oesophageal view 90° · (Dmax − Dmin) / Dmax × 100

SVC Dmax — expi (mm)

SVC Dmin — inspi (mm)

>36% = répondeur

4

IVC — Collapsibility (TTE) VS

IVC Dmax — expi (mm)

IVC Dmin — inspi (mm)

VS : >50% · VC : >18% = répondeur

5

PPV / SVV VC

PPV (%)

SVV (%)

VVE >13% · VVS >10% = répondeur

RV assessment and pulmonary pressures

RV systolic function

TAPSE (mm) N:≥17

Tricuspid S' N:≥10

FAC (%) N:>35

RV basal diam. (mm)

RV/LV ratio N:<0.6

RV free wall (mm)

Pulmonary pressures

SPAP = IT gradient + RAP = 4×(peak TR vel.)² + RAP

TR Vmax (m/s) TR signal not obtainable

IT gradient = 4×Vmax²

IT gradient (mmHg)

—

IVC (mm) N:<21

Calculated SPAP (mmHg)

—

IVC collapsibility → RAP

Pulm. Tacc (ms) N:>100

PR end-diast. vel. (m/s)

Conotch (mid-systolic notch)

Acute cor pulmonale signs

McConnell sign Paradoxical septum RV > LV RV/RA thrombus

Passive leg raising — Fluid responsiveness

LVOT VTI variation

1. Semi-recumbent 45° — measure baseline VTI · 2. Passive tilt to supine, legs at 45° · 3. Measure VTI within 60 s · 4. ↑ ≥10% = responder

Baseline LVOT VTI (cm)

Post-PLR LVOT VTI (cm)

Guided timer (60 s)

Waiting

1:00

Assessment guide — ESC 2021

Aortic Stenosis — follow the steps in order. Each result unlocks the next step.

1

Aortic peak velocity and mean gradient

View: Apical 5C or right parasternal (Pedoff) · Continuous-wave Doppler aligned with the Ao flow · Take the maximum value across 2–3 windows · Do not confuse with the MR signal

Aortic peak velocity (m/s)

Mild <3 · Mod. 3–4 · Severe ≥4

Mean gradient (mmHg)

Mild <25 · Mod. 25–40 · Severe ≥40

2

Aortic valve area (AVA) and DVI

AVA = (π × (LVOT D/2)² × LVOT VTI) / Ao VTI · DVI = LVOT VTI / Ao VTI · LVOT diameter in PLAX, 3–5 mm proximal to the valve, inner edge to inner edge

AVA (cm²)

Mild >1.5 · Mod. 1.0–1.5 · Severe <1.0

DVI (LVOT VTI / Ao VTI)

Mild >0.5 · Mod. 0.25–0.5 · Severe <0.25

3

Discordance / Low gradient

If AVA <1 cm² but gradient <40 mmHg → discordance. Check for low flow via LVEF and trans-aortic flow. CT calcium score if uncertain.

LVEF (%)

Ao flow (mL/s)

Low flow if <220 mL/s

Aortic Regurgitation — multiparametric quantification.

1

Vena contracta and AR/LVOT jet width

Vena contracta: PLAX, Nyquist 50–70 cm/s, minimal jet width in diastole · Jet/LVOT: Ratio of AR jet width / LVOT width at the same level

Vena contracta (mm)

Mild <3 · Mod. 3–6 · Severe >6

AR jet / LVOT (%)

Mild <25% · Severe >65%

2

PHT and descending Ao reflow

PHT: Continuous-wave Doppler aligned with the AR jet (A5C or A3C) · Holodiastolic reflow in descending Ao on parasternal or suprasternal view = severe AR

PHT (ms)

Mild >500 · Mod. 200–500 · Severe <200

Descending Ao reflow

3

Regurgitant volume and LV impact

Regurgitant vol. (mL)

Severe ≥60 mL

Regurgitant fraction (%)

Severe ≥50%

LVEF (%)

Surgical threshold <50%

LV ESD (mm)

Surgical threshold >50 mm

Mitral Stenosis — the Wilkins score guides the indication for percutaneous mitral commissurotomy (PMC).

1

Mitral valve area (MVA) and PHT

Planimetry: Parasternal short axis, leaflet tips level · PHT: MVA = 220/PHT (invalid after PMC or if severe AR) · Continuity: MVA = (Ao area × Ao VTI) / Mitral VTI

MVA (cm²)

Mild >1.5 · Mod. 1.0–1.5 · Severe <1.0

PHT (ms)

Severe if >220 ms

2

Mitral gradient and SPAP

Pulsed-wave then continuous-wave Doppler in A4C · Gradient is HR-dependent (AF = average ≥5 cycles) · SPAP >50 mmHg = indication criterion for PMC

Mean gradient (mmHg)

Mild <5 · Mod. 5–10 · Severe >10

SPAP (mmHg)

PHT if >50

3

Wilkins score

4 criteria scored 1–4: Mobility (1=very mobile / 4=immobile) · Thickening (1=4mm / 4=≥8mm) · Calcification (1=one area / 4=diffuse) · Subvalvular app. (1=normal / 4=major fusion)

Total Wilkins score (4–16)

≤8 → favorable for PMC · 9–11 → intermediate · >11 → surgery

Mitral Regurgitation — mechanism not identifiable: move on to the next step.

1

Mechanism (Carpentier)

Type I: Normal leaflets (perforation, annular dilation) · Type II: Hypermobility / Prolapse · Type IIIa: Systolic-diastolic restriction · Type IIIb: Systolic restriction (functional MR)

Carpentier type

2

Vena contracta and ERO/PISA

Vena contracta: PLAX, narrowest point of the jet, just downstream of the leaflets.

ERO (Effective Regurgitant Orifice) = actual area of the orifice through which blood regurgitates, calculated via the PISA method. The larger the ERO, the more severe the regurgitation.

In practice: set the Nyquist limit to 25–40 cm/s while zoomed on the valve. The machine calculates the ERO automatically in the PISA measurement package — simply report the displayed value.

Vena contracta (mm)

Mild <3 · Severe >7

ERO / PISA (cm²)

Value shown by the PISA package · Mild <0.20 · Severe ≥0.40

3

Regurgitant volume (calculated) and LV impact

Regurgitant volume = ERO × MR VTI (velocity-time integral of the MR jet by continuous-wave Doppler, same window as MR peak velocity). SONIC automatically calculates the regurgitant volume and fraction from the ERO entered in step 2.

MR VTI (cm)

Continuous-wave Doppler of the MR jet

Mitral SV (mL, optional)

To calculate the regurgitant fraction (RF)

LVEF (%)

Surgical threshold <60%

LV ESD (mm)

Surgical threshold >40 mm