Percutaneous Treatment of Atrial Functional Mitral Regurgitation

Atrial functional mitral regurgitation (aFMR), which results from atrial dilation without significant left ventricular dysfunction, accounts for approximately one-third of mitral regurgitation (MR) cases and is associated with a poor prognosis.

Although surgical intervention remains the standard treatment for MR, it is often not feasible in patients with multiple comorbidities. Alternative transcatheter approaches, such as edge-to-edge repair or transcatheter mitral valve replacement, have shown promising outcomes. However, these techniques may not be suitable in certain anatomical scenarios, such as when clip placement is not feasible or when there is risk of left ventricular outflow tract (LVOT) obstruction.

This analysis reports outcomes in 14 symptomatic patients with severe aFMR who were deemed ineligible for surgical or edge-to-edge interventions.

All patients were treated with the ALTAVALVE percutaneous mitral valve, which features atrial fixation using bovine pericardium. The device is implanted above the native mitral valve and does not interfere with LVOT function.

La edad media de los pacientes fue de 78 años; 10 de ellos eran mujeres. El puntaje STS promedio fue de 5,4%. Todos presentaban fibrilación auricular. La fracción de eyección promedio fue de 55%; el volumen sistólico auricular, de 191 ml; el volumen diastólico auricular, de 177 ml; el volumen sistólico ventricular izquierdo, de 70 ml; y el volumen diastólico ventricular izquierdo, de 149 ml. El gradiente mitral promedio fue de 1,9 mmHg, y el gradiente del tracto de salida del VI, de 1,4 mmHg.

Read also: ACURATE Neo2 Underexpansion: Prevalence and Clinical Implications.

The device was implanted via transseptal approach in 11 patients and transapical in the remaining 3. Procedural success was achieved in all cases.

At 30-day follow-up, there were two cases of non-cardiac mortality. No cardiac deaths, heart failure events, strokes, major bleeding, reinterventions, surgical conversions, or endocarditis were reported. Two patients required closure of the interatrial septum post-procedure. All surviving patients demonstrated improvement in functional class.

The 30-day echo Doppler showed mild MR in one patient, while the rest did not show residual MR. Mean mitral gradient was 5 mmHg, and right ventricular outflow tract gradient was 2.4 mmHg. No patients showed left ventricular outflow tract obstruction. 

Conclusión

The ALTAVALVE system showed promising results both at procedural and clinical levels at short term followup in patients with atrial functional mitral regurgitation. Further long term studies are needed to confirm the benefits of this device. 

Original Title: Transcatheter Mitral Valve Replacement With Atrial Fixation for Treatment of Atrial Functional Mitral Regurgitation. 

Reference: John T. Saxon, el at. Circ Cardiovasc Interv. 2025;18:e014985. DOI: 10.1161/CIRCINTERVENTIONS.124.014985.