Valvular echocardiography · primary mitral regurgitation

Reading primary MR parameter by parameter

Choose the grade, the mechanism and the colour gain: the apical four-chamber view, the convergence zoom and the three Doppler traces change together. Further down is the parasternal long axis, to recognise billowing, prolapse and flail. For each measurement you will find the cut-off, the sensitivity and the specificity that the original study actually reported, with the main limitation of that figure. Simplified teaching model: the simulator numbers come from geometric formulas, not from patients.

Simulator

The simulator starts from severe MR caused by posterior leaflet prolapse. Choose the lesion and the leaflet, then set each parameter (EROA, vena contracta, pulmonary vein, E/A, atrium) to mild, moderate or severe, or leave it on Auto so it follows the true grade. "Anatomy only" turns off colour and shows the annular plane and leaflet displacement. Raise the colour gain to see the jet and the VC enlarge while the PISA stays fixed.

A4C · ASE convention
Nyquist 40 cm/s
HR 65 bpm

Prolapse P2

CW mitral

Density and shape of the signal. A dense triangular profile with an early peak suggests a large atrial v wave.

PW mitral inflow

High E wave if the regurgitant volume returns to the ventricle in diastole. An A-dominant pattern argues against severe MR.

PW pulmonary vein

Dominant, blunted or reversed S wave. Systolic reversal is the specific sign. Full explanation below.

What S, D and Ar are

S: Systolic wave. Blood entering the atrium from the pulmonary veins while the ventricle is in systole and the mitral valve is closed. The atrium acts as a reservoir at that time. It has two components: S1, early in systole, due to atrial relaxation after contraction; S2, in mid-to-late systole, due to descent of the mitral annulus toward the apex and to the push arriving from the right ventricle through the pulmonary circulation. S1 and S2 separate well only at a low heart rate.
D: Diastolic wave. Blood passing from the veins to the ventricle through the atrium when the mitral valve opens: the atrium acts as a conduit. It follows the mitral E wave, and its deceleration mirrors that of E. It depends on ventricular filling, not on regurgitation.
Ar: Retrograde atrial wave. Small negative wave after the P wave: atrial contraction pushes a little blood back into the veins. Velocity and duration (Ar longer than mitral A) increase with end-diastolic ventricular pressure.

Dominant S, S higher than D. Low-pressure atrium that fills well in systole. This is the normal adult pattern and argues against severe MR. In healthy young people D may exceed S because of vigorous relaxation: this is not pathological.

Blunted S, S lower than D. The regurgitant jet fills the atrium in systole and raises its pressure (v wave): less gradient remains for venous inflow. Compatible with moderate MR, but the same blunted S is seen in AF (S1 disappears), high atrial pressures from diastolic dysfunction and a stiff atrium.

Reversed S. Atrial pressure in systole exceeds venous pressure and flow goes back into the veins. It is the specific sign of severe MR, but it is absent in about 4 of 10 severe cases (Enriquez-Sarano 1999): if present it confirms, if absent it does not exclude. The two veins can be discordant in about one case in four, more often with the right one more affected: sample both if you can.

How to record it: apical four-chamber view, PW sample volume of 3–5 mm placed 1 cm inside the right upper pulmonary vein, guided by colour, low wall filter, reduced scale.

True MR grade

Colour gain50%, normal

Lesion (Carpentier II)

Leaflet

Animation speed0.50x

Nyquist limit for PISA40 cm/s

Grade of each parameter

"Auto" follows the true grade. Setting a parameter to a different grade creates a discordant picture.

Overlays

Mid-systolic zoom on the orifice: aliasing convergence, PISA radius and vena contracta.

Measure	Value	Reading

Prolapse, billowing and flail

Parasternal long axis, zoomed on the mitral valve. The dashed yellow line is the annular plane: the caliper measures how far the leaflet passes beyond it toward the atrium. It starts without colour, so you can look at the anatomy alone: change the lesion and the leaflet and watch where the free edge ends up. Turn on the colour jet to see its direction.

PLAX · mitral zoom
End-systole to measure

Normal

Lesion

Leaflet involved

End-systolic measure	Value

Severity calculator

Set how many of the patients you see have severe MR (pre-test probability), then mark each parameter as present, absent or not assessed. Each result is weighted by its likelihood ratio, derived from the sensitivity and specificity of the cited study. Parameters without verified data stay excluded until you enter sensitivity and specificity yourself.

Pre-test probability30%

Correction for related parameters

Post-test probability of severe MR

–

0%20%80%100%

Parameter used	LR	Effect

How it calculates: post-test odds = pre-test odds × LR of each parameter. Positive LR = sens / (1 − spec); negative LR = (1 − sens) / spec. The method assumes independent parameters, but those in the same family (for example pulmonary vein, E wave and VTI, all consequences of regurgitant volume) are related. With partial correction the most informative one counts fully, the second with weight 1/2, the third 1/3 (LR raised to that weight): this is my own unvalidated choice, to avoid counting the same information twice. The MR Index is an alternative to the single parameters, not added to them. The reading thresholds (below 20%, above 80%) are my own choice.

MitraClip and M-TEER

Indications, anatomical criteria, COAPT profile and proportionality of secondary regurgitation. The anatomical and clinical criteria come from the review by Zygouri et al. (J Clin Med 2025, full text on PubMed Central); the recommendation classes come from the summary of the ESC/EACTS 2025 guidelines.

PRIMARY

Surgery first

Surgical repair is the first choice if the risk is acceptable
M-TEER for symptomatic high-risk or inoperable patients, with suitable anatomy and Heart Team decision: class IIa ESC/EACTS 2025 (was IIb in 2021)
Historical reference: EVEREST II, central jet, suitable leaflets, little calcium

SECONDARY, VENTRICULAR

After optimal therapy

Symptomatic despite optimal medical therapy and CRT if indicated
ESC/EACTS 2025: class I (LOE A) in highly selected patients
COAPT positive, MITRA-FR neutral: the difference is explained by proportionality
RESHAPE-HF2: benefit also in moderate MR

SECONDARY, ATRIAL

A separate entity

AF, large atrium, normal-volume ventricle
ESC/EACTS 2025: surgery IIa (often with ablation), TEER IIb in high-risk patients

OTHER SITUATIONS

Bridge and shock

Bridge to transplant or LVAD, or symptom relief outside COAPT criteria: class IIb
Cardiogenic shock: favourable observational data, trials needed

Anatomical suitability

Anatomical result

Criterion	Value	Level

Targets at the end of the procedure: valve area ≥ 1.5 cm², mean gradient < 5 mmHg, residual MR at most mild (MVARC: optimal none or trace, acceptable at least one grade less). Reduction of pulmonary vein reversal confirms atrial decompression.

COAPT profile (secondary, ventricular)

Verification result

COAPT criterion	Value	Result

For comparison, MITRA-FR included LVEF 15–40% and defined severe MR as EROA > 20 mm² or volume > 30 mL. The review warns that failing the COAPT criteria is not enough on its own to exclude a patient.

Proportionate or disproportionate

The "expected" EROA comes from the orifice equation: with total stroke volume = LVEDV × LVEF and a regurgitant fraction of 50%, EROA = LVEDV × LVEF × 0.5 / jet VTI. With LVEDV 220–250 mL and LVEF 30% this gives about 0.3 cm², as in Grayburn's example.

Result

Index	Value	Threshold

The two boxes are the examples from the Grayburn 2019 abstract (LVEDV 220–250 mL with EROA about 30 mm²; LVEDV 160–200 mL with EROA 30–40 mm²). The curve is the expected EROA for a regurgitant fraction of 50% at the entered LVEF. A point above the curve indicates MR larger than the ventricle explains (disproportionate, more likely to benefit from TEER); on or below the curve, proportionate (therapy that reduces volumes comes first).

Parameter atlas

For each measure I report only what I could read in the PubMed abstract. Where a study does not give sensitivity and specificity, I say so rather than invent a number. The reliability judgement is mine and you can dispute it. The full table, with all the studies found and the atrium, is in the accuracy sheet.

Pitfalls and tips

The most common mistakes made when measuring, grouped by technique. Almost everything comes from the ASE 2017 and EACVI 2022 recommendations and from shared laboratory experience; where a point rests on a specific study I cite it, where it is only practice I say so.

Pitfall an error that shifts the gradingTip an acquisition or reading technique

Before measuring

TipMeasure the blood pressure during the study and write it in the report. The jet and the PISA depend on the LV–LA gradient: a hypertensive patient at 170 mmHg can look worse than he really is.
PitfallSedation and anaesthesia unload the ventricle and reduce the jet. Pieper 1996 found, in TEE under anaesthesia, a lower jet-area cut-off than in awake patients.
PitfallIn AF every beat is different. Average at least 5 cycles, or choose beats with an RR interval similar to the previous one.
TipDefine the mechanism and the segment first: the direction of the jet tells you which leaflet is diseased (jet opposite the prolapsing leaflet) and warns you whether the PISA will be non-hemispherical.

Sources: ASE 2017, EACVI 2022, Pieper 1996.

Colour jet

PitfallCoanda effect: an eccentric jet that hugs the wall loses energy and looks small. A holosystolic eccentric wall-hugging jet should be considered potentially severe, not measured by area.
PitfallA low Nyquist limit or a high gain enlarges the jet. Work with a Nyquist limit of 50–70 cm/s and a gain just below the appearance of noise.
PitfallCentral jets entrain blood (entrainment) and overestimate, especially at high pressures.
TipA narrow sector and reduced depth raise the frame rate: below 15–20 fps the end-systolic jet is lost.
TipUse jet area only at the extremes: a tiny central jet to rule out, a jet filling the atrium up to the veins to suspect. In between it is not useful.

Sources: ASE 2017, EACVI 2022; Helmcke 1987, Hall 1997 for the limits of area.

Vena contracta

TipMeasure it in the parasternal long axis when possible: there the VC is measured with axial resolution, which is better than the lateral resolution of the apical views.
PitfallDo not use the bicommissural (two-chamber) view: it cuts the orifice along the coaptation line and artificially enlarges it.
TipZoom, narrow sector, Nyquist 50–70. Look for the three parts together: convergence above, narrow neck, jet widening below. Measure the neck, perpendicular to the jet axis.
PitfallOne millimetre of error on 5 mm is 20%. Average at least 3 beats.
PitfallWith multiple jets the VCs do not add up. 3D or another method is needed.
PitfallIn an elliptical orifice a 2D VC in a single plane underestimates or overestimates depending on the cut. There, the 3D VC area helps.

Sources: ASE 2017, EACVI 2022, Hall 1997, Zeng 2011.

PISA

TipShift the baseline in the direction of the jet (downward in apical views) to a Nyquist limit of 30–40 cm/s: the hemisphere gets larger and the radius becomes measurable with less relative error.
PitfallThe radius is squared: 1 mm of error on 8 mm shifts the EROA by about 25%. Use strong zoom and at least 3 measurements.
TipThe hardest point is the orifice, not the aliasing border. Scroll the cine loop with and without colour to see where the leaflets close.
TipQuick formula, a known rule of thumb: with a Nyquist limit of 40 cm/s and jet Vmax around 5 m/s, EROA in cm² ≈ r²/2 with r in cm. A radius of 0.9 cm gives about 0.40 cm². Use it to check, not to report.
PitfallIn flail and eccentric jets the convergence is hemi-elliptical or constrained by the wall. The hemispheric calculation is wrong; an angle correction exists (α/180), but it is poorly reproducible.
PitfallIn telesystolic prolapse the radius is maximal in a single frame. Multiplied by a full VTI it overestimates the volume. Use serial PISA or the volumetric method.
PitfallSuboptimal convergence in prolapse: Enriquez-Sarano 1995 found almost double EROAs in these cases (137 vs 84 mm²).
TipTake Vmax and VTI from the CW in the same cycle, or at least in cycles with the same RR interval, and check that Vmax is consistent with blood pressure.

Sources: ASE 2017, EACVI 2022, Enriquez-Sarano 1995. The r²/2 formula is common practice; I did not verify it on PubMed in this search.

Volumetric method

PitfallThe diameter of the outflow tract is squared: 2 mm of error on 20 mm changes the stroke volume by about 20%.
TipWith a good window, total stroke volume from biplane or 3D LV volumes minus forward stroke volume in the LVOT. 2D underestimates volumes: you risk underestimating the regurgitation.
PitfallWith significant aortic regurgitation the LVOT count no longer represents only the systemic forward stroke volume. Use the method with caution.
TipIf PISA and the volumetric method disagree by more than 20–30%, do not choose the one you like: it is time for CMR.

Sources: ASE 2017, EACVI 2022, Uretsky 2015.

Pulsed and continuous-wave Doppler

TipPulmonary vein: sample 1 cm inside the right upper pulmonary vein in the apical four-chamber view, low filter, reduced scale. If you can, look at the left one too.
PitfallThe two veins can show different patterns: discordance in 24% in Klein 1991 and 22% in Mark 1995, almost always with the right one more affected. Mark 1995 and Galjee 1995 (CMR) did not find that it depends on jet direction: do not assume that an eccentric jet "reverses only its own vein".
PitfallAF, high atrial pressures and LV dysfunction blunt the S wave without severe MR. Only a clear reversal carries weight.
TipE wave: sample at the tips of the leaflets. An A-dominant pattern in an elderly patient is the strongest argument against severe MR (Thomas 1998).
TipCW: at equal gain, compare the density of the jet with that of diastolic inflow on the same trace. If the jet is denser than the inflow, the volume is significant.
PitfallA weak CW signal may simply be misaligned. Look for the signal from several windows before calling it mild.
TipA triangular profile with an early peak means a high v wave. In telesystolic prolapse the signal starts in mid-systole: it is the sign that warns you of the PISA pitfall.

Sources: Klein 1991, Eren 2001, Thomas 1998, ASE 2017.

Prolapse anatomy

TipParasternal long axis: A2 and P2. Bicommissural two-chamber view: P3, A2, P1 from left to right. Short axis at the valve: all the scallops, to localise. 3D TEE en face in the surgical view removes any doubt.
PitfallProlapse is diagnosed in the long axis, not in the four-chamber view: the saddle-shaped annulus makes normal leaflets look prolapsing in apical views.
TipIn Barlow's disease look for mitral annular disjunction (MAD) and the Pickelhaube sign on lateral tissue Doppler: an arrhythmic profile to report.
TipRuptured chordae: the flail segment points toward the atrial roof, with a free tip and a mobile chordal fragment. This alone is enough to call it severe if the jet is consistent.

Sources: practice and ASE/EACVI recommendations. The correspondence between views and scallops varies with angulation: verify it in your own patient.

Consequences and timing

PitfallIn severe MR an LVEF of 60% already means dysfunction: the ventricle also ejects into the atrium. Do not write "preserved function" above 55% without comment.
PitfallA few millimetres decide the indication class (LVESD 38 vs 40 mm). Measure in the parasternal view with the same method, on the same machine at follow-up, and index it.
TipIndexed biplane atrial volume, not just diameter: since 2025 an atrium ≥ 60 mL/m² is among the criteria for class I in asymptomatic patients.
TipAsymptomatic with severe MR and doubtful symptoms: stress echo with PASP and grade of MR under exercise. In your lab it is the test that clarifies discordant cases.

Sources: ESC/EACTS 2025 through the cited summaries, ASE 2017. I have not re-checked the exercise thresholds.

Integrated approach

No single parameter is enough. The ASE 2017 and EACVI 2022 recommendations call for starting from the mechanism, looking for specific signs, quantifying when they disagree, and moving to TEE or CMR if doubt remains.

STEP 1

Mechanism

Carpentier I, II (prolapse, flail), IIIa
Segment involved: the jet direction is opposite the diseased leaflet
Flail with chordal rupture is already a sign of severity

STEP 2

Specific signs

Severe: VC ≥ 7 mm, large PISA (radius ≥ 10 mm at Nyquist 30–40), S reversal in the pulmonary vein, central jet > 50% of the atrium
Mild: VC < 3 mm, small jet, dominant S, A-dominant pattern

STEP 3

Quantification

EROA, volume and regurgitant fraction
Agreement between PISA and the volumetric method
In telesystolic prolapse the regurgitant volume outweighs the EROA of a single frame

STEP 4

If discordant

TEE, preferably 3D, for anatomy and VC area
Cardiac MRI for volume and regurgitant fraction
Stress echo if symptoms and the resting picture do not match

Parameter	Mild	Intermediate	Severe
Vena contracta	< 3 mm	3–6.9 mm	≥ 7 mm (≥ 8 mm if biplane)
EROA (PISA)	< 0.20 cm²	0.20–0.39 cm²	≥ 0.40 cm²
Regurgitant volume	< 30 mL	30–59 mL	≥ 60 mL
Regurgitant fraction	< 30%	30–49%	≥ 50%
Colour jet	small, central, < 20% of LA	variable	central > 50% of LA or holosystolic eccentric wall-hugging
Pulmonary vein	dominant S	blunted S	systolic reversal
Mitral inflow	A dominant	variable	E > 1.2 m/s
Mitral / aortic VTI	< 1.0	1.0–1.4	> 1.4

When to operate: ESC/EACTS 2025

Symptomatic severe primary MR: surgery, surgical repair if durable
Asymptomatic with LV dysfunction: LVEF ≤ 60%, LVESD ≥ 40 mm or indexed LVESD ≥ 20 mm/m²
Asymptomatic without dysfunction and at low risk: class I if at least 3 of the following are present: atrial fibrillation, PASP > 50 mmHg, left atrium ≥ 60 mL/m² or ≥ 55 mm, moderate or severe TR. With fewer than 3 criteria, class IIa

Classic pitfalls

Coanda effect: an eccentric wall-hugging jet looks small
Non-hemispheric PISA in flail and eccentric jets
Telesystolic prolapse: high peak EROA, modest volume
Colour gain and Nyquist change the jet area
AF, diastolic dysfunction and atrial pressures alter the E wave and pulmonary veins

Five cases to practise

Choose an answer. Each case has a button that loads it into the simulator.

Sources

All numerical data from the studies were read from the abstracts retrieved from PubMed. The grading thresholds come from the ASE 2017 and EACVI 2022 recommendations, which I did not re-read in full text: they should be checked there.

Limitations of this page

Many sensitivity and specificity values come from single-centre studies from the 1990s, with samples of 37 to 147 patients, mixed primary and secondary populations and a reference standard that is often echocardiographic. This inflates the apparent accuracy, because the test and the reference share the same errors.

The simulator uses simplified geometry: circular orifice, ideal hemisphere, fixed forward stroke volume of 60 mL, jet VTI 150 cm. It is meant to help understand the relationships between measurements, not to calibrate a report.