Case: Atrial functional MR with AF and HFpEF context
A 79-year-old woman has longstanding persistent AF, marked LA enlargement, progressive dyspnea, preserved LVEF, and moderate-to-severe MR. The regurgitation is likely driven by atrial remodeling and mitral annular dilation — not by ventricular systolic dysfunction. The management pathway differs from HFrEF-type ventricular functional MR.
Clinical scenario
79-year-old woman with longstanding persistent AF for 9 years and progressive exertional dyspnea over 18 months, NYHA Class II–III. TTE: mitral annular dilation, no obvious leaflet prolapse, flail leaflet, or rheumatic disease, qualitative MR moderate-to-severe, EROA 0.26 cm², LVEF 58%, markedly enlarged LA (LAVI 58 mL/m²), PASP mildly elevated at 38 mmHg, no regional wall motion abnormality, no significant LV systolic impairment. Rate controlled at 75 bpm on bisoprolol 5 mg. No anticoagulation failure documented.
Is this secondary MR from AF and LA remodeling? And how should management differ from ventricular functional MR?
Identifying the mechanism
The key features in this case are preserved LVEF (58%), markedly enlarged LA (LAVI 58 mL/m²), longstanding AF for 9 years, no regional wall motion abnormality, and MR without obvious primary leaflet pathology. This pattern strongly suggests atrial functional MR — where longstanding AF and LA enlargement dilate the mitral annulus and impair leaflet coaptation, rather than papillary muscle displacement from LV systolic dysfunction. In older patients, mild degenerative change or MAC may coexist, so the mechanism should be confirmed by integrated TTE/TEE assessment.
This tool classifies this finding as 'clinically important secondary MR in context.' EROA 0.26 cm² is below the ACC/AHA severe quantitative threshold. But in the setting of LAVI 58 mL/m², longstanding AF, progressive symptoms, and mildly elevated PASP, this is clinically meaningful MR that warrants careful management.
Why this is not a COAPT patient
COAPT primarily studied HFrEF patients with ventricular functional secondary MR. Trial eligibility required LVEF 20–50%. This patient has LVEF 58% — she is outside the COAPT population. The COAPT-like TEER pathway designed for HFrEF-type secondary MR should not be directly applied. The Secondary MR Intervention Navigator should branch this patient to the atrial functional MR pathway rather than the standard HFrEF/COAPT-like TEER evaluation pathway.
Management priorities in atrial functional MR
Start by asking whether AF and LA loading are adequately managed. Resting rate control at 75 bpm appears reasonable, but exertional rate response and symptomatic episodes should also be reviewed. Rhythm control with cardioversion or ablation may be considered — but after 9 years of AF and with marked LA enlargement (LAVI 58 mL/m²), the likelihood of durable sinus rhythm maintenance may be limited. When achievable, sinus rhythm can reduce LA loading and annular dilation, potentially improving MR. Any rhythm control strategy should be considered only after evaluating feasibility, risk, symptoms, and patient preference with electrophysiology input.
Volume and filling pressure management are also central. Diuretic adjustment, avoidance of fluid overload, BP control, and optimization of HFpEF therapy may reduce LA pressure and improve symptoms. If HFpEF is present, SGLT2 inhibitors should be considered when appropriate.
Evolving evidence for TEER in atrial functional MR
Evidence for TEER and surgery in atrial functional MR is evolving. Small series and registries report symptom improvement after TEER in selected AFMR patients with preserved LVEF — but this is not the same evidence base as COAPT for HFrEF-type secondary MR. COAPT-like HFrEF eligibility criteria should not be automatically applied to AFMR. If symptoms persist and AF, volume, and HFpEF management have been optimized, individualized Heart Valve Team evaluation for AFMR is the appropriate next step.
Perioperative implication
For elective noncardiac surgery, MR grade alone is not sufficient to assess risk in this patient. Key questions are: Is AF rate controlled at rest and during surgical stress? Is volume status optimized? Is filling pressure elevated from HFpEF or diastolic dysfunction? Is PASP elevated or RV function impaired? Can the patient tolerate perioperative fluid shifts? Is there pulmonary congestion or oxygenation vulnerability? Mildly elevated PASP (38 mmHg) with LAVI 58 mL/m² and longstanding AF suggests limited diastolic reserve — fluid loading or tachycardia during the perioperative period may worsen pulmonary congestion.
What is the most appropriate next step?
- 1.Reassess AF rate/rhythm management, optimize volume status and HFpEF therapy, and reassess MR in 3–6 months✓ Recommended
Correct. In atrial functional MR, AF management, volume and filling pressure optimization, BP control, and HFpEF therapy come first. MR may improve as LA loading and annular stress are reduced.
- 2.Refer for TEER using COAPT-like HFrEF criteria⚠ Not recommended
Not appropriate as an automatic pathway. LVEF 58% places this patient outside the COAPT LVEF 20–50% criterion. Evidence for TEER in AFMR is evolving and requires individualized Heart Valve Team evaluation, not COAPT-like HFrEF criteria.
- 3.Proceed with elective surgery — MR is only moderate by quantitative criteria△ Consider
Consider carefully. EROA 0.26 cm² is below the ACC/AHA severe quantitative threshold — but LAVI 58 mL/m², longstanding AF, HFpEF context, and mildly elevated PASP suggest limited diastolic reserve and vulnerability to fluid loading. This is not automatically low risk for surgery with significant hemodynamic stress.
Teaching points
- Atrial functional MR is driven by LA enlargement and mitral annular dilation — LVEF may be preserved, distinguishing it from HFrEF-type ventricular functional MR.
- COAPT eligibility criteria (LVEF 20–50%) do not apply to atrial functional MR with preserved LVEF.
- AF rate/rhythm management, volume and filling pressure optimization, BP control, and HFpEF therapy are first-line priorities.
- Evidence for TEER or surgery in AFMR is evolving — individualized Heart Valve Team evaluation is appropriate when symptoms persist despite optimized medical therapy.
- For perioperative physicians: AF, HFpEF, filling pressure, PASP, RV function, and volume tolerance determine perioperative risk more than MR grade alone in this population.
Apply this in practice
Use the Secondary MR Intervention Navigator — select atrial functional MR as the mechanism.
Secondary MR Intervention Navigator