Pediatric Balloon Valvuloplasty · AHA 2011: catheter peak-to-peak, sedated
How to measure (ASE 2024)
Maximum instantaneous and mean gradients from several views (subcostal, apical 3-chamber, right parasternal, suprasternal); note the view. Apical gradients tend to be lower than right parasternal. Pulsed Doppler along the outflow tract first, to localise the level.
With LV dysfunction, and in newborns, the gradient can be low despite significant stenosis: judge by valve morphology and aortic annulus z-score. A modest gradient with significant LV dysfunction is relatively severe (ASE 2010).
Continuity valve area, planimetry and pressure-recovery correction are not routine in children (little validation, measurement variability). If area is used, index it to BSA.
I
Any gradient: duct-dependent newborn with isolated critical AS, or isolated valvar AS with depressed LV systolic function.
B
I
Resting catheter gradient ≥50 mmHg.
B
I
Catheter gradient ≥40 mmHg with angina, syncope or ischemic ST-T changes (rest or exercise).
C
IIb
Catheter gradient ≥40 mmHg without symptoms or ST-T changes, planning pregnancy or strenuous competitive sport.
C
IIb
Asymptomatic, catheter <50 mmHg under heavy sedation or anesthesia, but non-sedated Doppler mean >50 mmHg.
C
III
Catheter gradient <40 mmHg without symptoms or ST-T changes; or AR already needing surgery.
C
Doppler vs catheter in children
Catheter gradients under general anesthesia are likely somewhat lower than these sedated values (AHA 2011 footnote).
Doppler mean tracked peak-to-peak at low gradients but underestimated higher ones (Barker 2002), and underestimated it in 83–94% of patients (Vlahos 2008).
Right parasternal peak instantaneous gradient ≤55 mmHg predicted no intervention in 79 children; the average of apical and right parasternal peaks best predicted the catheter gradient (Vlahos 2008).
Pressure recovery is larger in small children and milder stenosis; correcting for it brought Doppler closest to the catheter value (Barker 2002; Schlingmann 2015).
The 2017 document notes that indexing valve area is important in children, adolescents and small adults.
Low-flow, low-gradient criteria (stroke volume index <35 mL/m², dobutamine stress, calcium score) are adult constructs without pediatric validation.
Adult congenital AS (ACC/AHA 2025, Table 22): mild Vmax 2.0–2.9 m/s or mean <20 mmHg; moderate 3.0–3.9 or mean 20–39; severe ≥4.0 or mean ≥40.
Subvalvar AS in adults (ACC/AHA 2025): no gradient grades. Valvar AS grades may not suit setting an operative threshold; the optimal threshold in asymptomatic patients without significant AR is not known. Reported: peak gradient ≥50 mmHg with more AR and less intervention-free survival (in cited pediatric data, an echo gradient ≥50 mmHg was an independent risk factor for moderate–severe AR); a preoperative gradient ≥80 mmHg with later moderate AR (post hoc). Surgery: Class I (C-EO) for symptoms; IIb (C-LD) without symptoms if LV dysfunction or hypertrophy, or at least mild AR.
Critical PS (cyanotic, duct-dependent at birth); valvar PS with catheter peak-to-peak or echo peak instantaneous ≥40 mmHg; or clinically significant obstruction with RV dysfunction.
A
IIa
Dysplastic valve, same criteria.
C
IIa
Newborn PA/IVS, favorable anatomy, no RV-dependent coronary circulation.
The gradient can mislead with a large shunt that equalises pressures, the normally high newborn PA pressure, severe TR, or low RV output; then rely more on annulus size and leaflet morphology (ASE 2024).
Include the proximal velocity with subvalvar or serial obstruction; dynamic infundibular obstruction gives a late-peaking, dagger-shaped jet (EAE/ASE 2009). Severity may be underestimated with ventricular dysfunction (ACC/AHA 2025, Adult, Table 27).
ASE 2009: no specific Doppler gradients agreed for intervention; Doppler peak gradients tend to exceed catheter peak-to-peak; in children the highest gradient is often subcostal.
Mitral stenosis
MS Grading, Adult · EAE/ASE 2009, Table 9; ASE now defers to AHA/ACC stages. No validated pediatric grading scale.
Measure
Mild
Moderate
Severe
Valve area (cm²)
>1.5
1.0–1.5
<1.0
Mean gradient (mmHg)Heart rate 60–80, sinus rhythm
<5
5–10
>10
PA systolic pressure (mmHg)
<30
30–50
>50
Congenital MS in children
Mean gradient from the CW velocity-time integral; faster heart rates shorten diastole and raise it. Pressure half-time and continuity valve area correlate poorly with catheter data in congenital AV-valve stenosis and are not recommended routinely (ASE 2010, 2024).
Increased flow (VSD, PDA) raises the gradient; an ASD can decompress the left atrium and lower it. Gradients may be inaccurate with fast heart rates or intracardiac shunts.
AHA 2011 profile of the infant or child with at least moderate MS who met criteria for transcatheter treatment (not a severity scale): peak transmitral gradient ≥20 mmHg, mean ≥15 mmHg, near-systemic PA pressure, small calculated valve area, with respiratory symptoms or failure to thrive.
Balloon valvuloplasty: Class I for symptomatic or pulmonary-hypertensive moderate–severe rheumatic MS; Class IIa for symptomatic congenital MS with favorable anatomy at ≥5 years (AHA 2011). In adults with congenital MS it is rarely indicated or effective (ACC/AHA 2025).
Tricuspid stenosis
Group
Values
Source
Significant TS, Adult
How to measure
Average over the respiratory cycle; normal tricuspid inflow rarely exceeds 0.7 m/s. Isolated congenital TS is rare; AHA 2011 makes no pediatric recommendation. The mitral stenosis caveats (heart rate, ASD flow) apply.
Adult
Specific: mean gradient ≥5 mmHg; inflow VTI >60 cm; pressure half-time ≥190 ms; continuity area ≤1 cm².
Recoarctation: balloon Class I (C) if >20 mmHg with suitable anatomy, any age; or <20 mmHg with significant collaterals, single ventricle or significant ventricular dysfunction. Native: balloon Class IIb (C) beyond 4–6 months, >20 mmHg. Stent: Class I (B) recurrent >20 mmHg if adult-size stent fits; Class IIa native or recurrent >20 mmHg.
Suggests significance (Table 25): arm–leg systolic BP, Doppler mean, corrected maximum instantaneous (MIG) or catheter peak-to-peak gradient >20 mmHg; diastolic tail in the descending aorta with diastolic forward flow in the abdominal aorta; CMR or CT isthmus ratio <0.5–0.7; collaterals. Repair (surgery or stent) when anatomically and hemodynamically significant: Class I (B-NR).
Adult congenital
ACC/AHA 2025 (Adult): >20 mmHg applies to arm–leg systolic BP, Doppler mean, corrected MIG or catheter peak-to-peak; AHA 2011 (pediatric) uses catheter gradients. Of the Doppler gradients, the mean is closest to catheter peak-to-peak; uncorrected MIG needs a different cut-off. Gradients may be lower with LV dysfunction, severe AS or extensive collaterals; after repair, Doppler gradients may be high without narrowing (poor arterial compliance, pressure recovery) (Table 25 footnotes).
Echo signs
2D (suprasternal): long distance between left carotid and left subclavian arteries, isthmal tapering or a posterior shelf, color turbulence.
CW across the arch: two superimposed envelopes, the faster outer one from the narrowing and the dense inner one from proximal flow. Distal arch velocity is usually too high to ignore: include the proximal velocity in the Bernoulli equation.
Abdominal aorta pulsed Doppler (subcostal sagittal) often gives the first clue: delayed return to baseline suggests arch obstruction; blunted flow with no return to baseline is consistent with significant obstruction. A persistent forward "diastolic tail" is pathognomonic of hemodynamically significant coarctation (ASE/EACVI 2015, adult aorta guideline).
The gradient underestimates severity with collaterals, a PDA or ventricular dysfunction; in older patients use CT or MRI for anatomy. In a small study, a CW peak gradient >40 mmHg was 100% specific but 57% sensitive, and diastolic flow persistence (time to half-peak diastolic velocity >100 ms) was 100% specific and 79% sensitive (Carvalho 1990).
Measurement pitfalls in children
Nine pitfalls
Peak instantaneous is not peak-to-peak. Pediatric natural-history and intervention data use the catheter peak-to-peak gradient (except PS, where the echo peak is accepted).
Pressure recovery can make Doppler exceed the net pressure drop by up to 20–40% in children; greater in small children and milder stenosis. Correction is not routine for lack of pediatric validation.
Proximal velocity: include it when it exceeds 1.5 m/s or the jet is under 3 m/s: ΔP = 4(vmax² − vprox²). Routine along the arch and with serial obstructions.
Low flow masks severity: LV or RV dysfunction, newborns, large VSD or PDA, high neonatal PVR, collaterals. Use morphology and annulus z-scores.
Heart rate raises AV-valve mean gradients; the adult MS bands assume 60–80 bpm. Record it.
Window: right parasternal usually gives the highest AS gradient; in children the highest PS gradient may come from the subcostal window. Record the view.
Anesthesia: the AHA 2011 catheter thresholds assume sedation; general anesthesia likely gives somewhat lower gradients. AHA 2011 lets a non-sedated Doppler mean >50 mmHg count for AS (Class IIb).
Valve area in small outflow tracts: LVOT diameter error is magnified in children and planimetry is unreliable with doming valves. If used, index to BSA; adult area cut-offs are not validated in children.
Mean gradient is the average of instantaneous gradients, not 4 × (mean velocity)². Average 3 or more beats in sinus rhythm.
Key points
Pediatric thresholds use catheter peak-to-peak gradients (AHA 2011). ASE pediatric guidelines: no numeric severity grades.
Doppler peak instantaneous > catheter peak-to-peak; pressure recovery can account for up to 20–40% in children. Doppler mean underestimated higher peak-to-peak gradients (Barker 2002).
PS exception: echo peak instantaneous ≥40 mmHg counts like catheter for balloon (Class I).
Low gradient can hide severe obstruction (LV dysfunction, newborn, large VSD/PDA, high neonatal PVR, collaterals): use morphology and annulus z-score.
Report window and heart rate. Highest gradient: AS usually right parasternal; pediatric PS may be subcostal.
Lopez L, Saurers DL, Barker PCA, et al. Guidelines for performing a comprehensive pediatric transthoracic echocardiogram: recommendations from the ASE. J Am Soc Echocardiogr 2024;37:119-170. doi:10.1016/j.echo.2023.11.015.
Lopez L, Colan SD, Frommelt PC, et al. Recommendations for quantification methods during the performance of a pediatric echocardiogram. J Am Soc Echocardiogr 2010;23:465-495. doi:10.1016/j.echo.2010.03.019.
Feltes TF, Bacha E, Beekman RH 3rd, et al. Indications for cardiac catheterization and intervention in pediatric cardiac disease: a scientific statement from the AHA. Circulation 2011;123:2607-2652. doi:10.1161/CIR.0b013e31821b1f10 (archived publisher full text).
Baumgartner H, Hung J, Bermejo J, et al. Recommendations on the echocardiographic assessment of aortic valve stenosis: a focused update from the EACVI and the ASE. J Am Soc Echocardiogr 2017;30:372-392. doi:10.1016/j.echo.2017.02.009.
Baumgartner H, Hung J, Bermejo J, et al. Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. J Am Soc Echocardiogr 2009;22:1-23. doi:10.1016/j.echo.2008.11.029. ASE's cover note defers mitral stenosis grading to the AHA/ACC stages.
Gurvitz M, Krieger EV, Fuller S, et al. 2025 ACC/AHA/HRS/ISACHD/SCAI guideline for the management of adults with congenital heart disease. Circulation 2026;153(8):e115-e251 (co-published J Am Coll Cardiol 2026;87(7):822-976). doi:10.1161/CIR.0000000000001402 (archived publisher copy: Tables 22, 25 and 27, and the recommendation tables for congenital mitral, subaortic and valvular pulmonary stenosis and coarctation, read as images; the 2026 correction changes the author list only). Adults only.
Goldstein SA, Evangelista A, Abbara S, et al. Multimodality imaging of diseases of the thoracic aorta in adults: from the ASE and the EACVI. J Am Soc Echocardiogr 2015;28:119-182. doi:10.1016/j.echo.2014.11.015 (coarctation).
Carvalho JS, et al. Br Heart J 1990;64:133-137 (PMID 2393611).
How it was checked
Guideline tables were read in full (October 2026; ACC/AHA 2025 in November 2026) and copied by number; wording is condensed. The 2009 tables are images and were read from rendered pages.
The 2020 ACC/AHA valvular heart disease guideline could not be opened, so its stage tables (including the mitral stages ASE now defers to) are not reproduced.
On 2026-11-02 the adult congenital content moved from the 2018 AHA/ACC guideline (Stout 2019) to the 2025 guideline that replaces it. Changed: PS severe mean gradient >35 became >35–40 mmHg; adult AS grades gained mean-gradient bands. Not in 2025, so removed: the subvalvar AS grades (moderate >30 to <50, severe ≥50 mmHg maximum gradient), the coarctation criteria of >10 mmHg with LV dysfunction, AR or collaterals, and the note on RV pressure from the TR jet in PS.
ACC/AHA 2025 Table 22 defines ΔP as the peak gradient but labels the bands "mean ΔP"; the page shows mean.