Mitral stenosis: rheumatic and degenerative disease, PMC and surgery

This page covers native mitral stenosis (MS) in adults: its causes, severity grading, imaging, medical therapy, anticoagulation, the choice between percutaneous commissurotomy and surgery, pregnancy, non-cardiac surgery and follow-up. ESC/EACTS 2025 abbreviates percutaneous mitral commissurotomy as PMC, and ACC/AHA 2020 abbreviates percutaneous mitral balloon commissurotomy as PMBC; each term is kept with its own guideline here.^[1][3] Measuring valve areas and gradients is covered in Echo valve quantitation: areas, gradients, regurgitation grades. Anticoagulation and rhythm decisions in atrial fibrillation are covered in Atrial fibrillation. Valve choice and anticoagulation after mitral valve replacement are covered in Prosthetic heart valves: choice, anticoagulation and thrombosis. Pregnancy in women with heart disease is covered in Cardiovascular disease in pregnancy.

What causes mitral stenosis

ESC/EACTS 2025 says the aetiology of MS is most frequently rheumatic or degenerative, while rare forms can be drug-induced, inflammatory or carcinoid-related.^[1] Rheumatic fever is the most common cause of MS and death due to valvular heart disease (VHD) worldwide.^[1] Its prevalence has decreased in high- and middle-income countries, but remains a major healthcare problem in low-income countries, where it predominantly affects young patients.^[1] Degenerative MS related to mitral annular calcification (MAC) is a distinct age-dependent pathology requiring different treatment strategies, and both aetiologies are more frequent in females.^[1]

ACC/AHA 2020 says the incidence of rheumatic MS is low in high-income countries and has been slowly declining in low- and middle-income countries, but MS remains a major cause of valve disease worldwide.^[3] It says rheumatic MS is much more common in women (about 80% of cases) than in men.^[3] Nonrheumatic calcific MS is found with increasing frequency in the elderly population in high-income countries.^[3] ACC/AHA 2020 adds that nonrheumatic MS can also be present after radiation therapy and after a mitral valve repair with a small annuloplasty ring.^[3]

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How rheumatic stenosis progresses

ACC/AHA 2020 describes rheumatic MS as a slowly progressive disease, with a prolonged latent phase between the initial rheumatic illness and the development of valve stenosis.^[3] The latent phase is typically measured in decades in high-income countries but is considerably shorter in low- to middle-income countries, likely because of recurrent carditis.^[3] Once mild stenosis has developed, further narrowing is slow (a decrease in valve area of 0.1 cm² per year on average), although the rate of progression is highly variable.^[3] Progressive enlargement of the right ventricle (RV) and a rise in RV systolic pressure can be observed even in the absence of a decrease in mitral valve area.^[3]

Heart rate and rhythm change the haemodynamics of MS.^[3] ACC/AHA 2020 says the acute development of atrial fibrillation (AF) may have significant detrimental haemodynamic consequences, primarily from the rapid ventricular response, which shortens the diastolic filling period and increases LA pressure.^[3] In symptomatic patients in sinus rhythm with tachycardia, it says heart rate control with beta blockers, calcium channel blockers or ivabradine will lengthen the diastolic filling period and lower LA pressure.^[3] ESC/EACTS 2025 adds that pregnancy can worsen the clinical course of left-sided stenotic lesions, because increased cardiac output increases the transvalvular gradient by about 50%, mainly between the first and second trimesters.^[1]

Clinical presentation

In ACC/AHA 2020 Table 16, the symptoms of symptomatic severe MS (Stage D) are decreased exercise tolerance and exertional dyspnoea; Stages A to C have none.^[2] ACC/AHA 2020 lists the reasons symptoms change in established rheumatic MS.^[3]

• Symptoms may change with disease progression (ACC/AHA 2020). Recurrent episodes of rheumatic fever leading to further valve damage; progressive narrowing of the mitral valve from leaflet fibrosis and thickening; progressive pulmonary hypertension; or worsening of concomitant MR or other valve lesions.^[3]
• Symptom status may change with no change in MS severity (ACC/AHA 2020). An increased haemodynamic load (for example, pregnancy), new-onset or rapid AF, fever, anaemia, hyperthyroidism, or haemodynamic shifts in the perioperative period of noncardiac surgery.^[3]

In these cases, ACC/AHA 2020 says a repeat TTE can quantify the mitral valve gradient and area, as well as other parameters that may contribute to the change in symptoms.^[3] ACC/AHA 2020 also notes that older patients with MS often have multiple other cardiac and noncardiac comorbidities.^[3] Its examples are atherosclerotic disease, hypertension and diastolic dysfunction, all of which need to be considered in evaluation and management.^[3] ESC 2025 (pregnancy) says mitral valve stenosis is a common cause of heart failure (HF) during pregnancy.^[7]

Grading severity

The two guidelines define severe MS by valve area, but frame it differently.^[1][3] In its rheumatic MS section, ESC/EACTS 2025 says an MVA of ≤1.5 cm² in conjunction with clinical factors (symptoms, high risk of thromboembolism or haemodynamic decompensation) is indicative of clinically severe MS.^[1] It says mean transvalvular gradient and pulmonary pressures reflect the consequences of the stenosis and have prognostic value.^[1]

ACC/AHA 2020 says the definition of severe MS is based on the severity of symptoms, as well as the severity at which intervention will improve symptoms.^[3] A mitral valve area ≤1.5 cm² is considered severe, which typically corresponds to a transmitral mean gradient of more than 5 to 10 mm Hg at a normal heart rate.^[3] ACC/AHA 2020 defines the stages of MS by symptoms, valve anatomy, valve haemodynamics, and the consequences of valve obstruction on the LA and pulmonary circulation.^[3] It says haemodynamic severity is best characterised by valve area, either directly planimetered by 2D or 3D imaging or calculated from the diastolic pressure half-time.^[3]

ACC/AHA 2020 Table 16: Stages of MS (all four stages)

^[2]

The note under Table 16 says the transmitral mean pressure gradient should be obtained to further determine the haemodynamic effect of the MS.^[2] It is usually more than 5 to 10 mm Hg in severe MS.^[2] Because the mean gradient varies with heart rate and forward flow, it has not been included in the criteria for severity.^[2] PASP in the table stands for pulmonary artery systolic pressure.^[2]

^{[2] [3]}

Investigations

Transthoracic echocardiography

In its rheumatic MS section, ESC/EACTS 2025 says echocardiography is the preferred method for screening in endemic regions and for assessing the severity, extent of anatomical lesions and haemodynamic consequences of MS.^[1] Involvement of other valves, particularly secondary tricuspid regurgitation (TR), should be identified.^[1] Mitral valve area by 2D planimetry is the most commonly used measurement of stenosis severity, but 3D TTE and TOE have additional diagnostic value.^[1]

ACC/AHA 2020 indicates TTE in patients with signs or symptoms of rheumatic MS (COR 1, LOE B-NR).^[3] The row lists its purposes: to establish the diagnosis, quantify haemodynamic severity, assess concomitant valvular lesions and demonstrate valve morphology to determine suitability for mitral commissurotomy.^[3] Its supportive text says the parasternal long-axis window can identify the characteristic diastolic doming of the mitral valve, whereas short-axis scanning will demonstrate commissural fusion and allow planimetry of the mitral orifice.^[3] Use of 3D echocardiography (either TTE or TEE) provides greater accuracy of measurement of the mitral valve area.^[3]

ACC/AHA 2020 Section 6.1 adds that mean pressure gradient is highly dependent on transvalvular flow rate, the diastolic filling period and heart rate.^[3] Pressure half-time depends on LV and LA compliance as well as stenosis severity.^[3] It says other approaches, such as the continuity equation or Gorlin formula, may be used if discrepancies exist, and that these points pertain primarily to rheumatic MS.^[3] In its rheumatic MS section, ESC/EACTS 2025 says the presence and extent of leaflet and subvalvular calcifications influence treatment decisions, and that scoring systems have been developed to assess suitability for PMC.^[1]

Transoesophageal echocardiography

In its rheumatic MS section, ESC/EACTS 2025 says TOE should be systematically performed in PMC candidates to exclude LA thrombus or after an embolic episode, and may play an essential role for procedural guidance.^[1] ACC/AHA 2020 says that in patients considered for PMBC, TEE should be performed to assess the presence or absence of LA thrombus and to evaluate the severity of MR (COR 1, LOE C-LD).^[3] Its supportive text explains the MR point: shadowing of the LA on TTE may result in underestimation of MR severity, and MR that is more than mild is a contraindication to PMBC.^[3]

Exercise testing and catheterisation

In its rheumatic MS section, ESC/EACTS 2025 says exercise testing is indicated in asymptomatic patients or in patients whose symptoms are equivocal or discordant with the severity of stenosis.^[1] Exercise echocardiography gives additional information on exercise capacity and on changes in mitral gradient and pulmonary artery pressure, and is preferred over dobutamine stress echocardiography, especially when dobutamine is contraindicated.^[1] ACC/AHA 2020 recommends exercise testing with Doppler or invasive haemodynamic assessment in rheumatic MS with a discrepancy between resting echocardiographic findings and clinical symptoms (COR 1, LOE C-LD).^[3] The purpose, in that row, is to evaluate symptomatic response, exercise capacity, and the response of the mean mitral gradient and pulmonary artery pressure.^[3]

ACC/AHA 2020 says exercise is preferred in general as the more physiological test.^[3] If the patient cannot exercise, increasing the heart rate with manoeuvres such as leg lifts or sit-ups may be useful.^[3] For patients with nondiagnostic studies, or discordance between clinical and echocardiographic findings, it says cardiac catheterisation is useful.^[3] Catheterisation can measure absolute pressures in the LV, LA and pulmonary circulation at rest and with exercise.^[3] The LV-to-pulmonary wedge gradient will overestimate the true transmitral gradient because of phase delay and delayed transmission of pressure changes.^[3] The Gorlin equation can be used for an independent calculation of valve area.^[3]

Medical therapy

In its rheumatic MS section, ESC/EACTS 2025 says diuretics, beta-blockers, digoxin, non-dihydropyridine calcium channel blockers and ivabradine can improve symptoms by controlling volume overload and heart rate.^[1] It says prophylaxis of infective endocarditis is indicated as appropriate.^[1]

ACC/AHA 2020: Recommendations for Medical Therapy in Patients With Rheumatic MS (all three rows)

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ACC/AHA 2020 warns that routine heart rate control in rheumatic MS in sinus rhythm without tachycardia may result in chronotropic incompetence, preventing an adequate cardiac output response to exercise.^[3] It says beta blockers or ivabradine may improve symptoms only in patients who do not have underlying chronotropic incompetence.^[3] When medical therapy is considered for symptom relief, it reminds the reader that PMBC relieves symptoms in patients with an appropriate valve morphology.^[3]

Rhythm control

In its rheumatic MS section, ESC/EACTS 2025 says interventions to restore sinus rhythm (cardioversion or catheter pulmonary vein isolation) are unlikely to be successful in patients with untreated severe MS.^[1] If AF is of recent onset and the LA moderately enlarged, it says cardioversion can be attempted soon after successful intervention, or in patients with moderate MS combined with amiodarone treatment.^[1] ACC/AHA 2020 says rhythm control is more difficult to achieve in rheumatic MS.^[3] Its reason is that the rheumatic process itself may lead to progressive fibrosis and enlargement of the atria, fibrosis of the internodal and interatrial tracts, and damage to the sinoatrial node.^[3]

Anticoagulation

Anticoagulation in MS is about two questions: who needs it, and which drug.^[1] In its rheumatic MS section, ESC/EACTS 2025 says anticoagulation with a VKA with a target international normalised ratio (INR) between 2 and 3 is indicated in patients with AF.^[1] In the same sentence on AF, it says DOACs should be avoided in patients with an MVA of ≤2.0 cm² according to current evidence.^[1] ACC/AHA/ACCP/HRS 2023 adds that, historically, stroke risk in MS with AF was nearly 18-fold higher than in an age-, sex- and hypertension-matched population without AF.^[5]

Patients in sinus rhythm

In its rheumatic MS section, ESC/EACTS 2025 says that in patients in sinus rhythm, OAC is indicated after systemic embolism or if a thrombus is present in the LA.^[1] It says OAC should also be considered when TOE shows dense spontaneous echocardiographic contrast or an enlarged LA (M-mode diameter >50 mm or LA volume >60 mL/m²).^[1] ACC/AHA 2020 indicates a VKA in rheumatic MS with AF, a prior embolic event or an LA thrombus (COR 1, LOE C-LD).^[3] It says it is controversial whether long-term anticoagulation should be given to patients with rheumatic MS in sinus rhythm on the basis of LA enlargement or spontaneous contrast on TEE.^[3]

Which anticoagulant in AF

Choosing the anticoagulant in AF with mitral stenosis: the formal rows (selected rows of each table)

^{[1] [4] [5] [3] [15] [6]}

The wording of the threshold differs between documents, so read each row as written.^{[1][4][5][15][6]} ESC/EACTS 2025 writes rheumatic MS with an MVA ≤2.0 cm².^[1] ESC 2024 (AF) writes moderate-to-severe mitral stenosis, and ESC 2026 (HF) writes moderate or severe mitral stenosis.^[4][6] ACC/AHA/ACCP/HRS 2023 writes rheumatic MS or MS of moderate or greater severity.^[5] AHA/ASA 2021 (secondary stroke prevention) writes valvular AF (moderate to severe mitral stenosis or any mechanical heart valve), in patients with ischemic stroke or TIA.^[15] ESC 2024 (AF) adds that patients with other types of valve disease, such as MR, should preferentially be prescribed a DOAC, and that the term valvular AF is obsolete and should be avoided.^[4] It says VKAs are currently the only treatment option in AF patients with mechanical heart valves or moderate-to-severe mitral valve stenosis.^[4]

ESC/EACTS 2025 Table 4 (Revised recommendations) records the change from its previous edition as dated history.^[1] The ESC/EACTS 2021-version row said DOACs were not recommended in AF with moderate-to-severe MS (Class III, Level C).^[1] The ESC/EACTS 2025-version row says DOACs are not recommended in AF with rheumatic MS and an MVA ≤2.0 cm² (Class III, Level B).^[1]

The trial behind the DOAC restriction

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The INVICTUS abstract reports 560 primary-outcome events in the rivaroxaban group and 446 in the VKA group in the intention-to-treat analysis, and more permanent discontinuation of trial medication with rivaroxaban at all visits.^[9] ESC 2024 (AF) reports the trial as 4531 randomised patients with rheumatic heart disease and AF.^[4] In them, it says, VKAs led to a lower rate of composite cardiovascular events and death than rivaroxaban, without a higher rate of bleeding.^[4] It says 82% of the patients had a mitral valve area ≤2 (unit printed as cm), supporting the restriction of DOAC use in moderate-to-severe mitral stenosis.^[4] It adds that the DOAC versus VKA trials had excluded moderate-to-severe disease.^[4] ACC/AHA/ACCP/HRS 2023 describes the INVICTUS population as patients with AF, rheumatic heart disease and mitral stenosis.^[5] It reports a mean survival time to a primary outcome event (stroke, systemic embolism, MI, or death from vascular or unknown cause) of 1675 days on a VKA versus 1599 days on rivaroxaban (difference −76 days; 95% CI −121 to −31; P<0.001).^[5]

^{[4] [5] [1]}

Intervention: commissurotomy or surgery

In its rheumatic MS section, ESC/EACTS 2025 says the type (PMC or surgery) and timing of treatment should be decided on clinical characteristics, the anatomy of the valve and subvalvular apparatus, and local expertise.^[1] In general, it limits intervention to clinically severe rheumatic MS (MVA printed as <1.5 cm² in this sentence) in whom PMC is expected to have a significant impact on clinical outcome.^[1] In higher-income countries, where the incidence of rheumatic fever and the number of PMCs performed is low, it says PMC should be restricted to expert operators in specialised centres to improve safety and procedural success rate.^[1] Efforts should be made to increase the availability of PMC in lower-income countries, where access to treatment is limited for economic reasons.^[1]

ESC/EACTS 2025 Recommendation Table 8: PMC, mitral valve surgery and transcatheter intervention in clinically severe rheumatic and degenerative mitral stenosis (all six rows)

^[1]

Footnote c of Recommendation Table 8 says unfavourable characteristics for PMC can be defined by the presence of several of the following.^[1]

• Clinical characteristics (ESC/EACTS 2025, footnote c): old age, history of commissurotomy, NYHA class IV, permanent AF, severe PH.^[1]
• Anatomical characteristics (ESC/EACTS 2025, footnote c): echocardiographic score >8, Cormier score group 3 (calcification of MV of any extent as assessed by fluoroscopy), severe TR.^[1]

Abbreviations in the table, as ESC/EACTS 2025 defines them: NCS, non-cardiac surgery; PH, pulmonary hypertension; SPAP, systolic pulmonary artery pressure; TMVI, transcatheter mitral valve implantation.^[1] The scores themselves are defined in a supplementary table that is not held for this topic.^[1]

ESC/EACTS 2025 Figure 14 is titled Management of clinically severe rheumatic mitral stenosis (mitral valve area ≤1.5 cm²).^[1] Its legend defines high thromboembolic risk as a history of systemic embolism, dense spontaneous contrast in the LA or new-onset AF.^[1] It defines high risk of haemodynamic decompensation as SPAP >50 mmHg at rest, need for major NCS, desire for pregnancy or pregnant.^[1] The legend lists new-onset AF where the Recommendation Table 8 row lists new-onset or paroxysmal AF.^[1]

ESC/EACTS 2025 Table 8: Contraindications for percutaneous mitral commissurotomy in rheumatic mitral stenosis (all seven rows)

^{[1] [1]}

ESC/EACTS 2025 says PMC should be considered as a first-line treatment for anatomically suitable rheumatic MS with mild-to-moderate calcification without severe subvalvular impairment.^[1] Selected patients with unfavourable anatomical and clinical characteristics can still benefit from PMC, particularly if they are at increased surgical risk.^[1] Where PMC is contraindicated, it says surgical MV repair or, more frequently, replacement are good alternatives, and repair, although much more challenging than for primary MR, can be attempted at experienced centres.^[1] Long-term follow-up has shown favourable results after PMC despite a growing number of elderly patients with suboptimal clinical and anatomical characteristics.^[1]

After surgical commissurotomy or PMC, ESC/EACTS 2025 says in its rheumatic MS section that reintervention for symptomatic restenosis in most cases requires surgical valve replacement.^[1] Redo PMC can be proposed in selected candidates with favourable characteristics, if the predominant mechanism is commissural refusion.^[1] It also says treatment of low-gradient severe MS (MVA <1.5 cm², mean gradient <10 mmHg) is challenging, because these patients are often older and have unfavourable anatomy.^[1]

The ACC/AHA 2020 rows

ACC/AHA 2020: Recommendations for Intervention for Rheumatic MS (all six rows)

^[3]

The table footnote defines the asterisk: 2+ on a 0 to 4+ scale according to Sellar’s criteria, or less than moderate by Doppler echocardiography.^[3] ACC/AHA 2020 says the optimal treatment of rheumatic MS is either PMBC or surgery (open or closed commissurotomy).^[3] Both require a high level of expertise and should be performed at experienced centres.^[3] It says mitral valve replacement is an option only if there is no other option and the patient has severe limiting symptoms.^[3]

• What PMBC does (ACC/AHA 2020). One or more balloon catheters are advanced across the mitral valve and inflated, splitting the commissures.^[3]
• The randomised evidence (ACC/AHA 2020). Randomised trials have established the safety and efficacy of PMBC compared with surgical closed or open commissurotomy in patients with favourable valve morphology, less than 2+ MR and no LA thrombus.^[3]
• Favourable morphology (ACC/AHA 2020). Mobile and relatively thin valve leaflets, free of calcium, in the absence of significant subvalvular fusion.^[3]
• Clinical predictors (ACC/AHA 2020). Clinical factors such as age, NYHA class and the presence or absence of AF are also predictive of outcome.^[3]
• Low gradients (ACC/AHA 2020). Older patients with lower gradients (<10 mm Hg) will not have as good an outcome as patients with higher gradients, probably because of other concomitant problems that cause symptoms, such as LV diastolic dysfunction and LA noncompliance.^[3]
• Operators (ACC/AHA 2020). PMBC should be performed only by experienced operators, with immediate availability of surgical backup for potential complications.^[3]
• Durability (ACC/AHA 2020). Long-term follow-up shows 70% to 80% of patients with an initial good result after PMBC free of recurrent symptoms at 10 years, and 30% to 40% at 20 years.^[3]

ACC/AHA 2020 says mitral valve surgery is an established therapy for rheumatic MS, with commissurotomy (closed or open) the preferred approach when anatomy is favourable.^[3] With severe valvular thickening and subvalvular fibrosis with leaflet tethering, mitral valve replacement may be the best option.^[3] Because rheumatic MS progresses slowly over decades, it says surgery should be delayed until the patient has severe limiting symptoms (NYHA class III or IV), particularly if mitral valve repair is contemplated.^[3]

The supportive text explains three of the asymptomatic and exercise rows.^[3] An elevated pulmonary artery pressure indicates progressive elevation of LA pressure affecting the pulmonary circulation, and some patients develop intrinsic pulmonary vascular disease, with poorer long-term survival when pulmonary hypertension precedes intervention.^[3] New AF may be the equivalent of symptom onset, signifying progressive LA damage, and AF increases the risk of thromboembolic events, although no randomised trial proves the effectiveness of intervening early.^[3] Patients whose gradient rises to >15 mm Hg with exercise have been shown to improve symptomatically after PMBC.^[3]

Other valves

In its rheumatic MS section, ESC/EACTS 2025 says that for multiple VHD including MS, a comprehensive Heart Team evaluation and an individualised approach are necessary.^[1] Surgery is preferable to PMC in severe MS with severe aortic valve disease, unless the surgical risk is high.^[1] In selected cases with severe MS and moderate aortic valve disease, PMC can be performed to postpone surgery on both valves.^[1] In high-risk cases with concomitant severe TR, PMC may be considered in selected patients with sinus rhythm, moderate atrial enlargement and secondary TR due to post-capillary PH.^[1] In non-high-risk cases, surgery on both valves is preferred.^[1] ACC/AHA 2020 says patients with moderate or severe TR may have a better outcome with a surgical approach that includes tricuspid valve repair.^[3]

ESC/EACTS 2025 says mixed mitral valve disease is usually present in rheumatic valve disease or MAC, and if MVA is ≤1.5 cm², recommendations for isolated MS apply.^[1] Patients with an MVA of >1.5 cm² and moderate MR may be evaluated for valve replacement.^[1] That evaluation is based on symptoms, anatomical characteristics, transmitral gradient, and signs of cardiac damage such as LA dilatation, AF or PH.^[1]

Degenerative mitral stenosis with annular calcification

ESC/EACTS 2025 says MAC is an indicator of cardiovascular disease severity and is associated with an increased risk of AF, stroke and death.^[1] Most patients with MAC do not have significant valvular dysfunction.^[1] Treatment options, transcatheter and surgical, are high-risk procedures, and evidence from RCTs is lacking.^[1]

A 2021 AHA/ASA secondary stroke prevention row (Section 5.4.2) covers patients with ischemic stroke or TIA and native aortic or nonrheumatic mitral valve disease (eg, mitral annular calcification or mitral valve prolapse) who do not have AF or another indication for anticoagulation.^[15] For these patients, it says antiplatelet therapy is recommended to reduce the risk of recurrent stroke or TIA (COR 1, LOE C-EO).^[15]

On imaging, ESC/EACTS 2025 says echocardiography is used for initial evaluation but is frequently limited by acoustic shadowing due to severe calcification.^[1] Evaluation of MVA by planimetry is less reliable than in rheumatic MS, so TOE should be used liberally.^[1] Degenerative MS can coexist with varying degrees of MR, and mean transmitral gradient has been shown to be associated with increased mortality irrespective of MR severity.^[1] Electrocardiogram-gated CT is necessary to assess the degree and locations of calcifications, especially if an intervention is planned; calcifications are usually more prominent at the posterior aspect of the annulus.^[1]

ACC/AHA 2020 says determining severity is difficult, because extensive calcification prevents an accurate planimetered area and abnormal LA and LV compliance cause a high gradient in the absence of severe obstruction.^[3] It says the progression of calcific MS is variable, ranging from an increase of <1.0 to up to 9 mm Hg per year.^[3]

On treatment, ESC/EACTS 2025 recommends intervention in symptomatic patients who are not responsive to medical therapy, weighing the potential benefits of the procedure against its associated risks.^[1] In elderly patients with degenerative MS and MAC, it says surgery is technically challenging and high risk.^[1] However, it says surgical MV repair or replacement with extensive decalcification and patch reconstruction of the annulus can be performed in selected patients at experienced centres (e.g. young patients post-chest radiation), where mortality rates of <5% have been reported.^[1] A TAVI prosthesis implanted in the mitral position is feasible in symptomatic high-risk patients with suitable anatomy.^[1] It is associated with frequent complications, including LVOT obstruction, valve embolisation, stroke and haemolysis due to paravalvular leak.^[1]

Open surgical valve replacement via the LA with a TAVI device allows complete anterior leaflet removal, but ESC/EACTS 2025 says mortality remains high.^[1] It encourages dedicated TMVI devices because they appear to be safer.^[1] ESC/EACTS 2025 Recommendation Table 8 says TMVI may be considered in symptomatic patients with extensive MAC and severe MV dysfunction at experienced Heart Valve Centres with expertise in complex MV surgery and transcatheter interventions (Class IIb, Level C).^[1] Heart Team evaluation should guide the choice of treatment avoiding futility, because mortality remains high even after successful treatment (10%–30% within 1 year).^[1]

ACC/AHA 2020 has one row for severely symptomatic patients (NYHA class III or IV) with severe MS (mitral valve area ≤1.5 cm², Stage D) attributable to extensive MAC.^[3] ACC/AHA 2020 says valve intervention may be considered only after discussion of the high procedural risk and the individual patient’s preferences and values (COR 2b, LOE C-LD).^[3] Because calcification involves the annulus and base of the leaflets without commissural fusion, it says there is no role for PMBC or surgical commissurotomy.^[3] It says intervention should be delayed until symptoms are severely limiting and cannot be managed with diuresis and heart rate control.^[3]

Follow-up

In its rheumatic MS section, ESC/EACTS 2025 says asymptomatic patients with clinically severe MS who have not undergone intervention should be followed up yearly by TTE, and at longer intervals (2–3 years) in cases of moderate stenosis.^[1] It says that after PMC, the post-procedural MVA and mean mitral gradient are important parameters that influence long-term clinical outcomes, and follow-up after successful PMC is necessary because asymptomatic restenosis may occur.^[1] Progressive rheumatic involvement of other valves should be periodically assessed, irrespective of the therapy modality.^[1] Education and the engagement of the family are key in rheumatic MS, since it usually affects young individuals and women of childbearing age.^[1]

ACC/AHA 2020 Table 5: Frequency of Echocardiograms in Asymptomatic Patients With VHD and Normal LV Function (Mitral Stenosis column)

^[3]

The Table 5 notes say patients with mixed valve disease may require serial evaluations at intervals earlier than recommended for single-valve lesions.^[3] The intervals apply to most patients with each valve lesion and do not take into consideration the etiology of the valve disease.^[3] ACC/AHA 2020 says repeat TTE at intervals dictated by valve area is an important aspect of disease management, even in patients without symptoms.^[3]

^{[3] [1]}

Prognosis

• Haemodynamics (ESC/EACTS 2025, rheumatic MS section). Mean transvalvular gradient and pulmonary pressures reflect the consequences of MS and have prognostic value.^[1]
• Pulmonary hypertension (ACC/AHA 2020). Patients who have pulmonary hypertension before intervention have a poorer long-term survival rate.^[3]
• After PMBC (ACC/AHA 2020). 70% to 80% of patients with an initial good result are free of recurrent symptoms at 10 years, and 30% to 40% at 20 years.^[3]
• Calcific MS (ACC/AHA 2020). The prognosis is poor, with a 5-year survival rate <50%, most likely because of advanced age and other comorbidities.^[3]
• Degenerative MS after treatment (ESC/EACTS 2025). Mortality remains high even after successful treatment (10%–30% within 1 year).^[1]

Special populations and scenarios

Pregnancy

ESC 2025 (pregnancy) says mild stenosis is usually well tolerated, but symptoms may occur if the valve area is <1.5 cm².^[7] Maternal mortality in mitral stenosis is higher with NYHA class above II, systolic pulmonary arterial pressure >30 mmHg, severe stenosis, older age and in low-income countries.^[7] Foetal risks include increased rates of premature delivery, intrauterine growth restriction (IUGR) and foetal death, especially in highly symptomatic mothers (NYHA III/IV).^[7] ESC/EACTS 2025 says HF occurs in one-third of pregnant women with an MVA of <1.5 cm² and in one-half of those with an MVA of <1.0 cm², most often during the second trimester.^[1]

ESC 2025 (pregnancy) says valve area by 2D planimetry is thought to be more reliable during pregnancy than flow-dependent measures, because higher stroke volume and tachycardia increase the measured gradient.^[7] If signs or symptoms of PH are present, activity restriction should be suggested, and beta-blockers and/or diuretics should be started.^[7] It says full therapeutic-dose LMWH or VKA is indicated with AF, left atrial clot or a previous embolism, and that anticoagulation regimens should be individualised.^[7] Anticoagulation should be considered with significant mitral stenosis, spontaneous echo contrast in the left atrium, a dilated left atrium with an LA volume index above 60 (unit printed as mL/mL²), or HF.^[7]

ESC 2025 pregnancy, Recommendation Table 18: native valve disease and pregnancy (selected rows)

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ESC 2025 (pregnancy) says that before and during pregnancy, percutaneous mitral balloon commissurotomy is the primary intervention in women who remain in NYHA III/IV or with severe PAP elevation despite medical therapy.^[7] Balloon techniques are highly successful during pregnancy unless there is complex subvalvar involvement, and closed commissurotomy is rarely used but is an alternative.^[7] Open valve surgery should only be used when there is a risk to maternal life and other options are not possible or have failed.^[7] ESC/EACTS 2025 adds that PMC should be considered if symptoms or SPAP >50 mmHg persist despite optimal medical therapy (diuretics and beta-1-selective beta-blockers), preferably after the 20th week of pregnancy.^[1]

Before pregnancy, ESC/EACTS 2025 says MS with MVA <1.5 cm² needs to be corrected, even when asymptomatic, and that the first therapeutic option for MS in a woman considering pregnancy should be PMC.^[1] When a prosthetic valve is necessary, it recommends biological valves, although early structural valve deterioration remains a serious concern.^[1] On delivery, ESC 2025 (pregnancy) says vaginal delivery is preferred, and caesarean section is preferred in severe mitral stenosis and in refractory HF.^[7] Close monitoring is needed in the days after delivery, diuretics may be required to treat fluid overload, and lifelong follow-up is required.^[7]

The 2020 ACC/AHA rows give the US view.^[3] ACC/AHA 2020 says PMBC at a Comprehensive Valve Center is reasonable before pregnancy in asymptomatic women with severe rheumatic MS who are considering pregnancy and have favourable valve morphology (COR 2a, LOE C-LD).^[3] That row gives the valve area as ≤1.5 cm² and prints the stage as Stage C1.^[3] ACC/AHA 2020 says that during pregnancy, PMBC is reasonable in severe rheumatic MS (Stage D) with morphology favourable for PMBC and NYHA class III or IV symptoms despite medical therapy, if performed at a Comprehensive Valve Center (COR 2a, LOE B-NR).^[3] Its supportive text says balloon dilation is a high-risk procedure during pregnancy for both the mother and the fetus.^[3]

In AF during pregnancy, ESC 2025 (pregnancy) says DOACs are contraindicated, and the presence of mechanical valves or moderate to severe mitral stenosis requires a VKA.^[7]

Non-cardiac surgery

ESC/EACTS 2025 says heart rate and fluid balance should be controlled to prevent pulmonary oedema during NCS, and arterial vasodilators should be avoided.^[1] NCS is safe with an MVA of >1.5 cm², and in asymptomatic patients with MVA ≤1.5 cm² and SPAP <50 mmHg.^[1] Symptomatic patients or those with SPAP >50 mmHg should undergo PMC or other appropriate valve intervention before high-risk NCS, if possible.^[1] Asymptomatic patients with MVA ≤1.5 cm² can undergo low-to-moderate-risk NCS under careful monitoring, especially if PMC is unsuitable, and multidisciplinary management is advised for significant MS ineligible for valve intervention.^[1]

The 2022 ESC non-cardiac surgery guideline gives the formal row, in its Recommendation Table 21 under the heading Mitral valve stenosis.^[8] In patients with moderate-to-severe rheumatic MS and symptoms or SPAP >50 mmHg, ESC 2022 recommends valve intervention (PMC or surgery) before elective intermediate- or high-risk NCS (Class I, Level C).^[8] Its text calls valve area ≤1.5 cm² moderate-to-severe MS and says NCS carries a relatively low risk in mild MS (valve area >1.5 cm²) and in asymptomatic moderate-to-severe MS with SPAP <50 mmHg on echocardiography.^[8] Because transmitral gradients are flow-sensitive, it says tachycardia and fluid overload can cause pulmonary oedema during NCS, so arterial vasodilators should be avoided and surveillance for peri-operative AF is of paramount importance.^[8]

ESC 2022 adds that a multidisciplinary team should manage moderate-to-severe MS ineligible for PMC, with NCS performed only if necessary.^[8] Intermediate-risk NCS may be performed in asymptomatic severe MS with appropriate intra-operative and post-operative haemodynamic monitoring, if valve morphology is unsuitable for PMC.^[8] US perioperative rows are not given here: the ACC/AHA 2020 valve guideline’s own noncardiac surgery rows have been followed by the 2024 and 2026 AHA/ACC perioperative guidelines, and the 2026 edition is not held as text for this topic.

Congenital mitral stenosis in adults

The 2025 ACC/AHA/HRS/ISACHD/SCAI adult congenital heart disease guideline gives two recommendations for congenital mitral stenosis, including Shone complex, in its Section 4.2.2.^[12] ACC/AHA/HRS/ISACHD/SCAI 2025 says adults with congenital mitral stenosis or a parachute mitral valve should be evaluated for additional left-sided obstructive lesions to guide management (COR 1, LOE B-NR).^[12] ACC/AHA/HRS/ISACHD/SCAI 2025 says adults with multiple left-sided obstructive lesions (Shone complex) and suspected pulmonary hypertension should undergo invasive haemodynamic assessment to identify and classify pulmonary hypertension (COR 1, LOE C-LD).^[12] It says that in many instances, indications for intervention in congenital mitral valve disease can be extrapolated from the 2020 ACC/AHA valvular heart disease guideline.^[12] However, it says balloon mitral valvuloplasty is rarely indicated or effective in congenital mitral stenosis.^[12] Its Table 10 (Congenital Heart Conditions Considered Significantly High Risk for Maternal Complications in Pregnancy) lists severe, symptomatic, left-sided obstructive lesions (mitral stenosis, subaortic and aortic stenosis) among its congenital heart lesions.^[12]

Sport and exercise

The 2020 ESC sports cardiology guideline says the risk stratification of exercising individuals with MS is based largely on a detailed echocardiogram, with specific interest in the severity of the lesion and the accompanying systolic pulmonary artery pressure (sPAP).^[13] It adds that assessment should include a maximal exercise stress test to identify concealed symptoms and functional capacity.^[13] In its text, asymptomatic individuals with mild MS (MVA 1.5–2.0 cm²) and moderate MS (MVA 1.0–1.5 cm²) who are in sinus rhythm and demonstrate good functional capacity on exercise testing and a normal sPAP may participate in all competitive and leisure sports.^[13] Mildly symptomatic individuals with severe MS (MVA <1.0 cm²) may only participate in leisure exercise involving physical effort of low intensity.^[13] Individuals with symptomatic MS should be referred for intervention and advised to abstain from participation in sports and recreational exercise of moderate or high intensity.^[13] Individuals with AF should be anticoagulated and avoid contact or collision sport.^[13] After balloon mitral valvuloplasty with good results (MVA >2.0 cm²), it says regular exercise and competitive sport may be considered in asymptomatic individuals with good functional capacity.^[13] These are statements from its text (no class or level given): in the held text, its two mitral stenosis recommendation tables have titles, footnotes and images but no row text, so their rows and classes are not given here.^[13]

The 2025 AHA/ACC scientific statement on competitive sports participation gives clinical considerations for mitral stenosis (no class or level given).^[14] It says competitive athletes with mild left-sided valve disease, including mitral stenosis, can participate in competitive sports.^[14] It says competitive sports participation is reasonable for asymptomatic competitive athletes with moderate mitral stenosis and normal exercise tolerance.^[14] In competitive athletes with asymptomatic severe mitral stenosis, it says the risks, which include the provocation of atrial arrhythmias, may outweigh the benefits of competitive sports participation.^[14] In competitive athletes with any severity of mitral stenosis and a history of AF who must receive anticoagulant therapy, it says the risks of some competitive sports involving collisions or impacts likely outweigh benefits.^[14]

Evidence, guidelines and regional differences

• Who gets intervention when asymptomatic. ESC/EACTS 2025 says PMC should be considered in asymptomatic patients without unfavourable clinical and anatomical characteristics who have high thromboembolic risk or high risk of haemodynamic decompensation, including SPAP >50 mmHg at rest (Class IIa, Level C). ACC/AHA 2020 says PMBC is reasonable, if it can be performed at a Comprehensive Valve Center, in asymptomatic severe rheumatic MS (Stage C) with favourable morphology, less than 2+ MR, no LA thrombus and PASP >50 mm Hg (COR 2a, LOE B-NR).^[1][3]
• New AF. ESC/EACTS 2025 lists new-onset or paroxysmal AF among the high thromboembolic risk limbs of its Class IIa, Level C row; ACC/AHA 2020 says PMBC may be considered, if it can be performed at a Comprehensive Valve Center, in asymptomatic severe rheumatic MS with favourable morphology, less than 2+ MR and no LA thrombus who have new onset of AF (COR 2b, LOE C-LD).^[1][3]
• Valve area above 1.5 cm². ESC/EACTS 2025 Table 8 lists MVA >1.5 cm² as a contraindication but says PMC may be considered with symptoms that cannot be explained by another cause if the anatomy is favourable. ACC/AHA 2020 says PMBC may be considered, if it can be performed at a Comprehensive Valve Center, in symptomatic rheumatic MS with a mitral valve area >1.5 cm² if a wedge pressure >25 mm Hg or mean gradient >15 mm Hg during exercise shows haemodynamically significant MS (COR 2b, LOE C-LD).^[1][3]
• The DOAC threshold. ESC/EACTS 2025 does not recommend DOACs in AF with rheumatic MS and an MVA ≤2.0 cm² (Class III, Level B). ACC/AHA/ACCP/HRS 2023 recommends long-term warfarin over DOACs in rheumatic MS or MS of moderate or greater severity with a history of AF, independent of the CHA2DS2-VASc score, to prevent cardiovascular events, including stroke or death (COR 1, LOE B-R).^[1][5]
• Degenerative MS. ESC/EACTS 2025 says TMVI may be considered in symptomatic patients with extensive MAC and severe MV dysfunction at experienced Heart Valve Centres with expertise in complex MV surgery and transcatheter interventions (Class IIb, Level C). ACC/AHA 2020 says that in severely symptomatic patients (NYHA class III or IV) with severe MS (mitral valve area ≤1.5 cm², Stage D) attributable to extensive MAC, valve intervention may be considered only after discussion of the high procedural risk and the individual patient’s preferences and values (COR 2b, LOE C-LD).^[1][3]

ANZ practice: the 2020 Australian guideline for acute rheumatic fever (ARF) and rheumatic heart disease (RHD), from RHDAustralia, is described in a 2021 Medical Journal of Australia paper.^[10] Its abstract says ARF and RHD cause significant morbidity and premature mortality among Australian Aboriginal and Torres Strait Islander peoples, and that GRADE was used to assess evidence where appropriate.^[10] Its listed changes include stratifying pregnancy risks according to RHD severity and a priority classification system for the presence and severity of RHD to align with appropriate timing of follow-up.^[10] The 2024 CSANZ position statement on TTE in structural and valvular heart disease aims to give clinicians a framework of acceptable indications for initial and serial TTE, and imaging providers the minimum standard for TTE examinations and reporting.^[11] Only the PubMed abstracts of these two ANZ documents are used. For the RHDAustralia guideline only the abstract of its Medical Journal of Australia paper is held, and the full text held for the CSANZ statement is a pre-publication proof (article in press), which is not quoted because it is not the version of record. No NHFA/CSANZ guideline on the management of valvular heart disease was found among the guidelines checked for this topic, so the ESC/EACTS, ESC and ACC/AHA rows above apply. Guidelines used for this topic: 2025 ESC/EACTS valvular heart disease; 2020 ACC/AHA valvular heart disease; 2024 ESC atrial fibrillation; 2023 ACC/AHA/ACCP/HRS atrial fibrillation; 2026 ESC heart failure; 2025 ESC cardiovascular disease and pregnancy; and 2022 ESC non-cardiac surgery. Also used were the 2025 ACC/AHA/HRS/ISACHD/SCAI adult congenital heart disease guideline, the 2020 ESC sports cardiology guideline, the 2025 AHA/ACC competitive sports statement, the 2021 AHA/ASA secondary stroke prevention guideline and the two ANZ documents above. Also checked was a PubMed census of mitral stenosis and rheumatic heart disease guidance and trials to October 2026. The currency sweep covered 46 held documents: 42 from the cardiology guideline register, the 2025 AHA/ACC competitive sports statement, the 2021 AHA/ASA secondary stroke prevention guideline, and the published corrections to that guideline and to the 2025 ACC/AHA/HRS/ISACHD/SCAI adult congenital heart disease guideline. For each formal class row, each of these documents published in the same month as that row’s guideline or later was swept for recommendations on mitral stenosis, rheumatic heart disease, commissurotomy, mitral annular calcification or the choice of anticoagulant in mitral stenosis. Not held as text for this topic, and so not used: the 2026 AHA/ACC perioperative guideline for noncardiac surgery and the 2018 NHFA/CSANZ atrial fibrillation guideline.

Complications and pitfalls

Exam pearls

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References15ShowHide

1. [1]Praz F, et al. 2025 ESC/EACTS Guidelines for the management of valvular heart disease. Eur Heart J, 2025.PMID 40878295
2. [2]Otto CM, et al. 2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation, 2021.PMID 33332150
3. [3]Otto CM, et al. 2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. J Am Coll Cardiol, 2021.PMID 33342586
4. [4]Van Gelder IC, et al. 2024 ESC Guidelines for the management of atrial fibrillation developed in collaboration with the European Association for Cardio-Thoracic Surgery (EACTS). Eur Heart J, 2024.PMID 39210723
5. [5]Joglar JA, et al. 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation, 2024.PMID 38033089
6. [6]Køber L, et al. 2026 ESC Guidelines for the management of heart failure. Eur Heart J, 2026.PMID 42661420
7. [7]De Backer J, et al. 2025 ESC Guidelines for the management of cardiovascular disease and pregnancy. Eur Heart J, 2025.PMID 40878294
8. [8]Halvorsen S, et al. 2022 ESC Guidelines on cardiovascular assessment and management of patients undergoing non-cardiac surgery. Eur Heart J, 2022.PMID 36017553
9. [9]Connolly SJ, et al. Rivaroxaban in Rheumatic Heart Disease-Associated Atrial Fibrillation. N Engl J Med, 2022.PMID 36036525
10. [10]Ralph AP, et al. The 2020 Australian guideline for prevention, diagnosis and management of acute rheumatic fever and rheumatic heart disease. Med J Aust, 2021.PMID 33190309
11. [11]Chong A, et al. 2024 CSANZ Position Statement on Indications, Assessment and Monitoring of Structural and Valvular Heart Disease With Transthoracic Echocardiography in Adults. Heart Lung Circ, 2024.PMID 38749800
12. [12]Gurvitz M, et al. 2025 ACC/AHA/HRS/ISACHD/SCAI Guideline for the Management of Adults With Congenital Heart Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation, 2026.PMID 41411375
13. [13]Pelliccia A, et al. 2020 ESC Guidelines on sports cardiology and exercise in patients with cardiovascular disease. Eur Heart J, 2021.PMID 32860412
14. [14]Kim JH, et al. Clinical Considerations for Competitive Sports Participation for Athletes With Cardiovascular Abnormalities: A Scientific Statement From the American Heart Association and American College of Cardiology. J Am Coll Cardiol, 2025.PMID 39976316
15. [15]Kleindorfer DO, et al. 2021 Guideline for the Prevention of Stroke in Patients With Stroke and Transient Ischemic Attack: A Guideline From the American Heart Association/American Stroke Association. Stroke, 2021.PMID 34024117