Use of Echocardiography in the Evaluation of Rheumatic Heart Disease
Basic Concepts of Pathophysiology, Clinical Presentation, and Screening
- RHD is the long-term consequence of ARF.
- Rheumatic carditis from ARF is due to immune-mediated injury to the heart following group A β-hemolytic streptococcus (S. pyogenes) infection, with antibodies developed in response to streptococcal pharyngitis subsequently cross-reacting with cardiac proteins in a susceptible host.
- Valvulitis is the most consistent feature of rheumatic carditis and commonly associated with mitral or aortic valve regurgitation.
- Echocardiographic evidence of valvulitis is a major criterion in the diagnosis of subclinical carditis.
- More than trace AR or MR in children should be considered pathological and may indicate rheumatic carditis or RHD, provided non-rheumatic causes are excluded.
- Pathological valvular regurgitation suggesting carditis should include pansystolic MR or pandiastolic AR seen in more than 1 view with peak velocity >3 m/s in at-risk populations.
- Measurement of valve thickness should be performed with tissue harmonics turned off as this modality increases apparent tissue thickness.
Rheumatic Valve Lesions
- Rheumatic MS is defined by a transmitral mean pressure gradient >4 mmHg and typical morphological changes in the valve consistent with a rheumatic process: thickened mitral leaflets, commissural fusion, restricted MV leaflet motion, diastolic doming of the anterior mitral leaflet, and/or chordal thickening/calcification.
- Severe rheumatic MS is indicated by MVA ≤1.5 cm2, PHT ≥150 msec, and transmitral mean gradient ≥10 mmHg.
- MS should be evaluated in a comprehensive approach, including a careful examination of valve morphology with 2DE, accurate determination of MVA by planimetry at the level of the leaflet tips, with 3DE multiplanar guidance if needed, hemodynamic assessment with Doppler echocardiography to determine PHT and mean pressure gradient, and supportive data, such as pulmonary artery pressure estimation and left atrial size.
- Planimetry is the preferred method for determination of anatomic MVA. The imaging plane should be positioned at the leaflet tips, and the smallest orifice area should be traced in zoom mode, with an optimized gain setting to avoid signal “drop-out”.
- Excessive gain, which can result in MVA underestimation, should be avoided.
- The cardiac rhythm and heart rate should be noted as part of Doppler assessment of MS.
- When the CWD spectral pattern of mitral inflow is bimodal with an initial rapid deceleration followed by a slower rate of decline, the linear portion of the mid-diastolic slope should be traced for PHT, rather than using the early steep deceleration slope.
- Stress echocardiography should be considered in patients whose symptoms are incongruent with echocardiographic data and for risk stratification of patients with MS. A transmitral mean gradient >15 mmHg during exercise echocardiography (or ≥18 mmHg during dobutamine echocardiography) should be considered hemodynamically significant rheumatic MS and identifies patients who might benefit from intervention.
Rheumatic Mitral Regurgitation
- An integration of multiple parameters is essential to examining rheumatic MR.
- Severe rheumatic MR is indicated by a VC ≥0.7 cm, VC area ≥0.40 cm2, regurgitant orifice area ≥0.4 cm2, regurgitant volume ≥60 mL, and regurgitant fraction ≥50 %.
- Quantitative indices include effective regurgitant orifice area (EROA) by PISA, regurgitant volume (using the PISA-derived method, continuity equation, or by 3DE), and regurgitant fraction (a ratio of regurgitant volume to forward stroke volume).38
- Semiquantitative parameters include VC, which is relatively unaffected by loading conditions and may be used with eccentric MR jets (common in RHD), VC area by 3DE color Doppler, and mitral to aortic valve VTI ratio (>1.4 suggests severe MR and <1 indicates mild MR41 in the absence of moderate or severe aortic valve regurgitation).
- Supportive data include mitral inflow peak E velocity, mitral inflow E/A ratio, pulmonary venous flow pattern, CWD profile of the MR jet, and LA and LV size.
- A quantitative approach should be used when more than moderate central MR is observed.
- Quantification of MR severity by VC and the PISA method should be included in the assessment of rheumatic MR, whenever feasible.
- 3DE with real-time volumetric imaging should be attempted whenever feasible, as it adds to the echocardiographic characterization of anatomic pathology of MR. Combined with color Doppler, 3DE is superior to traditional 2D PISA measurement of MR severity and provides an accurate VC area.
Rheumatic Aortic Valve
- The presence of commissural fusion and thickening of the free edges of the AV leaflets helps identify rheumatic involvement.
- Doppler assessment of rheumatic AR remains in keeping with the same principles detailed in the previous recommendations on native valvular regurgitation.
- Severe AS is suspected when transaortic flow Vmax ≥4 m/s, mean pressure gradient ≥40 mmHg, AVA < 1 cm2, indexed AVA <0.6 cm2/m2, and the ratio of LVOT velocity and AV velocity <0.25.
- Severe AR is indicated by a dense CWD jet density, PHT <200 msec, VC width >0.6 cm, regurgitant jet width/LVOT width ≥65 %, regurgitant volume ≥60 ml, regurgitant fraction ≥50 %, and EROA ≥0.3 cm2. Flow reversal in the descending aorta and LV enlargement are present.
- 2D and Doppler assessment of rheumatic AS should be complemented by a multiparametric approach that includes anatomic AVA determined by planimetry, effective AVA calculated from the continuity equation, AVA indexed to BSA, mean pressure gradient, transvalvular peak flow velocity, Doppler velocity index, and acceleration time.
- Valve anatomy should be assessed in the parasternal long- and short-axis views of 2DE, with the use of zoom mode.
- In the presence of significant leaflet doming, AVA by planimetry should be guided by 3D multiplanar imaging for optimal positioning of the imaging plane at the level of the leaflet edges to avoid overestimation of AVA.
- Assessment of the severity of rheumatic AR should rely on qualitative, semi-quantitative, and quantitative Doppler measurements together with the assessment of LV size and function.
- 3DE with color Doppler should be considered to assess VC area in moderate and severe rheumatic AR.
- In case of discrepant results, a careful review of potential technical errors or supportive findings should be performed. They include the angle of Doppler interrogation, location of the LVOT sample volume, accuracy of the LVOT diameter measurement, systemic blood pressure, BSA, high output states, and low flow conditions.
Rheumatic Tricuspid Stenosis
- TS occurs in concert with rheumatic mitral and/or aortic valve disorders.
- Anatomic appraisal of rheumatic TS requires assessment of the degree of valve thickening, calcification, commissural fusion, mobility, diastolic doming, and shortening of subvalvular structures, measurement of TVA, RA size, and notation of presence of any thrombi.
- Hemodynamic appraisal of TS includes mean TV pressure gradient, TVA, and estimation of RA and PA pressures.
- TS is hemodynamically significant with a mean gradient ≥5 mmHg, inflow VTI ≥60 cm, and TVA ≤1 cm2. PHT ≥190 or 220 msec may be used, but this method is less reliable than in MS.
- The severity of TS should be assessed by a multi-parametric approach including valve area, mean transvalvular gradient, RA size, an estimate of PA pressures, and evaluation of the hemodynamics of associated valve disorders.
- 3DE should be considered to measure TVA in multiplanar images for an eccentrically oriented TV orifice.
Rheumatic Tricuspid Regurgitation
- An echocardiographic diagnosis of primary rheumatic TR is made when there is TR associated with typical diastolic doming or thickening of the valve.
- TR is considered severe if the color Doppler regurgitant jet area is >10 cm2 at a Nyquist limit >50 cm/sec, VC is ≥0.7 cm in the apical four-chamber or RV inflow view, VC area is >0.4 cm2 via 3DE, PISA radius is ≥0.9 cm, EROA is ≥0.40 cm2, and regurgitant volume is ≥45 ml by 2D PISA. Not all of these findings may be present in all patients with severe TR.
- Supportive findings of severe TR include systolic flow reversal in a hepatic vein, tricuspid inflow E-wave velocity >1.0 m/s, and dense CWD waveform of the regurgitant jet.
- The severity of TR should be determined by assessment of color Doppler regurgitant jet area, VC width and area, PISA radius, EROA, and regurgitant volume.
- Multiplanar images of 3D datasets should be used whenever possible to help identify the correct short-axis orientation to measure the TVA and VC area.
- In patients with concomitant rheumatic MR and AR, increased LV filling pressures can increase pulmonary venous pressure. The regurgitant volume of TR may accordingly increase despite unchanged regurgitant orifice area, thus exaggerating TR severity by Doppler assessment. Also, functional TR may reverse with normalization of LV function/filling pressure. Thus, integrated hemodynamic and anatomic assessment of rheumatic TR should always be taken into consideration for clinical decision-making.
Rheumatic Pulmonic Valve
- Rheumatic PV disease is rare, always associated with MS, and typically manifests as stenosis.
- Severe rheumatic PS has a peak velocity >4 m/s and a mean gradient >35 mmHg.
- Severe PR is defined as a jet width/annulus diameter ≥70%, a PR jet PHT <100 msec, and a deceleration time of the PR spectral Doppler waveform <260 milliseconds.
- Severity of PR in the setting of RHD should be assessed in a manner similar to that of nonrheumatic PR.
- Quantitative RV size and function assessment should be included in patients with rheumatic PV.
Assessment of Mixed Valve Disease
- In suspected AS and concurrent rheumatic mitral disease, evidence for a possible low-flow state should be sought by examining LVOT flow determined by 3D TEE, CT, CMR or cardiac catheterization. The severity of low-flow AS should be supported by Doppler velocity index and AVA by CT, if necessary.
- Dobutamine challenge is not recommended to differentiate pseudo-severe from true severe AS in the setting of concomitant significant rheumatic MV disease, as forward stroke volume across the AV may not augment reliably with severe rheumatic MS and/or MR, regardless of contractile reserve of the LV.
- Measurement of anatomic valve area by planimetry should be performed in cases of combined MS and AS.
- In concurrent AR and MS, care should be taken to align the Doppler cursor with mitral inflow, distinguished from the AR jet. The timing of the jet may help distinguish one from the other, with the MS flow confined to diastole while AR starts at AV closure.
- When AR and AS of more than moderate severity coexist, the AVA calculated by the continuity equation remains applicable. Mean gradient and peak velocity are predictors of worse outcomes and should be considered in decision-making.
- The use of volumetric quantification of regurgitation is rendered inaccurate in the presence of multivalvular rheumatic involvement.
- The use of harmonic imaging is not recommended for assessing valve thickness in RHD.
- Temporal and spatial resolution should be optimized by decreasing scan depth and sector width, positioning the focus at the level of the valve being inspected, and employing the zoom function to magnify the structure of interest before making measurements.
- Gain settings should be adjusted to sufficiently image the contours of the mitral leaflets. Optimal adjustment of dynamic range (compression) may be needed to enhance leaflet border recognition.
- Multiple windows are employed for Doppler interrogation to best align the beam with blood flow during assessment of a valvular lesion.
- When imaging with 3DE, time gain compensation should be increased to avoid potential signal dropout and subsequent loss of diagnostic information. Excessive gains, however, may result in a loss of depth perception and a decrease in resolution.
- Post-exercise imaging during treadmill stress echocardiography should be acquired immediately after stopping exercise, preferrably in the first 2 minutes of recovery.
- Supine bicycle exercise is the preferred modality when assessing hemodynamic consequences of rheumatic valve lesions.
- Because the development of PH is an important clinical sequela in the course of RHD and correlates with more advanced disease, a thorough echocardiographic evaluation should include estimation of PASP and quantitative analysis of right heart size and function.
- In estimating PASP, measurement of peak TR velocity after an extrasystolic beat should be avoided.
- If the Doppler spectral envelope of the peak TR velocity is not well visualized, the measurement should be repeated with an ultrasound enhancing agent or agitated saline for better delineation of the peak velocity. Only the peak of a well-defined, dense spectral envelope (modal velocity) should be measured, excluding artifact or noise, to avoid overestimating the peak velocity.
- Analysis of each cardiac chamber size and function should be performed comprehensively, using multimodality echocardiography.
- Imaging of the LAA should involve both TEE and 3DE.
- Strain imaging should be applied whenever possible to assess chamber function in subclinical RHD.
- Echocardiographic Information needed for patient selection for PBMV should include  degree of thickening and calcification of leaflets and commissures,  extent and symmetry of commissural fusion,  severity of subvalvular thickening, shortening, and fusion,  severity of MR, if present, and  presence of LA or appendage clots.
- Intraprocedural 2D and 3D TEE is recommended to guide transseptal puncture as well as passage and inflation of the balloon catheter.
- Immediately post-procedure, transmitral pressure gradient and MVA by planimetry should be measured.
- PHT should not be used to calculate MVA immediately after PBMV.
- Post PBMV, the echocardiographic examination should include screening for potential complications, including cardiac tamponade, the severity of MR, and the extent of iatrogenic ASD.
Use of Echocardiography in the Evaluation of Rheumatic Heart Disease
November 23, 2022
Country of Publication
Male, Female, Adolescent, Adult, Child, Older adult
Health Care Settings
Hospital, Outpatient, Operating and recovery room
Nurse, nurse practitioner, physician, physician assistant
Assessment and screening, Management
echocardiography, rheumatic heart disease, heart disease
Pandian NG, Kim JK, Arias-Godinez JA, Marx GR, Michelena HI, Chander Mohan J, Ogunyankin KO, Ronderos RE, Sade LE, Sadeghpour A, Sengupta SP, Siegel RJ, Shu X, Soesanto AM, Sugeng L, Venkateshvaran A, Campos Vieira ML, Little SH. Recommendations for the Use of Echocardiography in the Evaluation of Rheumatic Heart Disease: A Report from the American Society of Echocardiography. J Am Soc Echocardiogr. 2023 Jan;36(1):3-28. doi: 10.1016/j.echo.2022.10.009. Epub 2022 Nov 23. PMID: 36428195.