Rheumatic mitral stenosis with new atrial fibrillation in a young woman — case discussion

Presentation

Practice case (not a real patient). A 26-year-old woman from a remote community in northern Australia has two weeks of palpitations. She is breathless walking uphill (NYHA class II). Rheumatic heart disease was diagnosed when she was a teenager. The ECG shows atrial fibrillation at 128 bpm. Echocardiography shows rheumatic mitral stenosis with commissural fusion, diastolic doming and pliable noncalcified leaflets.^[2][3] The planimetered mitral valve area is 1.0 cm² and the estimated PASP 52 mm Hg.^[2] The left atrium is moderately enlarged, MR is mild, and there is no aortic or tricuspid valve disease. She would like to have children.

Step 1 — How severe is it?

ESC/EACTS 2025 says an MVA of ≤1.5 cm² with clinical factors, such as symptoms, is indicative of clinically severe MS.^[1] She has symptoms, and the legend of ESC/EACTS 2025 Figure 14 (management of clinically severe rheumatic MS) lists new-onset AF as a high thromboembolic risk feature.^[1] Her valve area, PASP and exertional dyspnoea match the Stage D cells of ACC/AHA 2020 Table 16 (symptomatic severe MS).^[2] That table lists severe rather than moderate LA enlargement for Stage D.^[2] ACC/AHA 2020 says patients from regions with a high disease prevalence present at a young age (teen years to age 30 years), with commissural fusion but pliable noncalcified leaflets.^[3]

Step 2 — Rate and anticoagulation

ACC/AHA 2020 says the rapid ventricular response of acute AF shortens the diastolic filling period and increases LA pressure.^[3] ACC/AHA 2020 says heart rate control can be beneficial in rheumatic MS with AF and a rapid ventricular response (COR 2a, LOE C-LD).^[3] ESC/EACTS 2025 says a VKA with a target INR between 2 and 3 is indicated in patients with AF.^[1] ESC/EACTS 2025 Recommendation Table 2 does not recommend DOACs in AF with rheumatic MS and an MVA ≤2.0 cm² (Class III, Level B).^[1] ACC/AHA/ACCP/HRS 2023 recommends long-term warfarin over DOACs in rheumatic MS with a history of AF, independent of the CHA2DS2-VASc score, to prevent cardiovascular events, including stroke or death (COR 1, LOE B-R).^[5] In INVICTUS, VKA therapy led to a lower rate of a composite of cardiovascular events or death than rivaroxaban in rheumatic heart disease-associated AF.^[9]

Step 3 — Is she a candidate for percutaneous commissurotomy?

ESC/EACTS 2025 says TOE should be systematically performed in PMC candidates to exclude LA thrombus.^[1] ACC/AHA 2020 says TEE should be performed before PMBC to look for LA thrombus and evaluate MR severity (COR 1, LOE C-LD).^[3] Her TOE shows no thrombus and mild MR. Her echocardiographic score is 6 with no calcification. She has none of the seven contraindications in ESC/EACTS 2025 Table 8.^[1] Her MVA is not above 1.5 cm², there is no thrombus, MR is not more than mild and commissural fusion is present.^[1] There is no calcification and no other valve or coronary disease needing surgery.^[1]

Footnote c of Recommendation Table 8 says unfavourable characteristics for PMC can be defined by the presence of several of the following.^[1] The clinical ones are old age, history of commissurotomy, NYHA class IV, permanent AF and severe PH.^[1] The anatomical ones are echocardiographic score >8, Cormier score group 3 and severe TR.^[1] She has none of them; her AF is new rather than permanent.^[1]

Step 4 — Which rows apply?

For clinically severe MS, ESC/EACTS 2025 Recommendation Table 8 recommends PMC in symptomatic patients in the absence of unfavourable characteristics for PMC (Class I, Level B).^[1] ACC/AHA 2020 recommends PMBC in symptomatic patients (NYHA class II, III or IV) with severe rheumatic MS (mitral valve area ≤1.5 cm², Stage D) (COR 1, LOE A).^[3] That row also needs favourable valve morphology, less than moderate (2+) MR, no LA thrombus and a Comprehensive Valve Center that can perform it.^[3] ESC/EACTS 2025 says that in higher-income countries, where the incidence of rheumatic fever and the number of PMCs performed is low, PMC should be restricted to expert operators in specialised centres.^[1] She is referred to a specialised centre for the procedure.

Step 5 — Rhythm after the procedure

ESC/EACTS 2025 says interventions to restore sinus rhythm are unlikely to be successful in untreated severe MS.^[1] Her AF is of recent onset and her LA moderately enlarged, so ESC/EACTS 2025 says cardioversion can be attempted soon after successful intervention.^[1] ACC/AHA 2020 says rhythm control is more difficult in rheumatic MS.^[3] It gives the reason 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]

Step 6 — Planning a pregnancy

ESC 2025 (pregnancy) recommends intervention before pregnancy in women with mitral stenosis and a valve area <1.5 cm² (Class I, Level C).^[7] ESC/EACTS 2025 says the first therapeutic option for MS in a woman considering pregnancy should be PMC.^[1] If she becomes pregnant while in AF, ESC 2025 (pregnancy) says DOACs are contraindicated and moderate to severe mitral stenosis requires a VKA.^[7] ESC 2025 (pregnancy) recommends full therapeutic-dose anticoagulation in women with mitral stenosis complicated by AF, left atrial thrombus or prior embolism (Class I, Level C).^[7] ESC/EACTS 2025 says education and family engagement are key in rheumatic MS, which usually affects young individuals and women of childbearing age.^[1]

Step 7 — Follow-up and local guidance

ESC/EACTS 2025 says the post-procedural MVA and mean mitral gradient influence long-term outcomes after PMC.^[1] It says 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] The 2020 Australian ARF and RHD guideline lists a priority classification system for RHD to align with appropriate timing of follow-up.^[10] Only its abstract is held, so its classes are not given here.