Clin Res Cardiol (2025). DOI 10.1007/s00392-025-02737-x
1Ostalb-Klinikum Aalen Innere Medizin II, Kardiologie und Angiologie Aalen, Deutschland; 2Ostalb-Klinikum Aalen Pädiatrie Aalen, Deutschland; 3Universitätsklinikum Giessen und Marburg GmbH Klinik für Innere Medizin - Schwerpunkt Kardiologie Marburg, Deutschland
Background:
In patients with atrial fibrillation (AF), functional mitral regurgitation (FMR) often results from a combination of left atrial enlargement with annular dilation and impaired left ventricular (LV) function. This reflects the close interaction between atrial and ventricular remodeling processes. Pulmonary vein isolation (PVI) is a rhythm control strategy that may support reverse remodeling on both levels and potentially reduce the severity of mitral regurgitation. However, data on echocardiographic outcomes after PVI in this specific patient population, particularly those with heart failure with reduced (HFrEF) or mildly reduced ejection fraction (HFmrEF), are still limited.
Methods:
In this observational cohort study, 51 patients with AF, left ventricular ejection fraction (LVEF) <50% (HFrEF or HFmrEF), and moderate or severe FMR underwent first-time PVI between 2020 and 2023. The cohort had a mean age of 69.3 ± 9.1 years and was 64% male. Paroxysmal AF was present in 43% of patients, and 57% had persistent AF. Transthoracic echocardiography was performed before the procedure and at 12-month follow-up to assess LVEF, left atrial (LA) diameter, and MR severity, including vena contracta width and effective regurgitant orifice area (EROA). Rhythm status was evaluated using standard 12-lead electrocardiograms and 24-hour Holter monitoring at 6 and 12 months.
Results:
After 12 months, mean LVEF significantly improved, increasing from 41.6 ± 6.8% at baseline to 48.4 ± 11.3% at follow-up (p < 0.01). This improvement was observed in patients who maintained sinus rhythm (+7.3 ± 7.9%) and those with AF recurrence (+6.1 ± 8.1%), with no significant difference between groups (p = 0.47). Despite improvements in systolic function, MR severity remained stable over the 12-month period. Vena contracta width showed no significant change (4.5 ± 0.9 mm vs. 4.3 ± 1.1 mm, p = 0.31), and EROA remained unchanged (0.29 ± 0.08 cm² vs. 0.28 ± 0.09 cm², p = 0.44). MR severity at follow-up did not differ significantly between patients with and without sinus rhythm (p > 0.05 for all comparisons). LA diameter decreased modestly from 49.2 ± 5.6 mm to 47.8 ± 6.1 mm, though this change did not reach statistical significance (p = 0.09). No major procedural or follow-up complications were observed.
Conclusion:
In this cohort of patients with AF, at least moderate functional MR, and LVEF <50% (HFrEF or HFmrEF), PVI was associated with a significant improvement in LV systolic function after 12 months, independent of rhythm status at follow-up. However, MR severity remained unchanged. The observed improvement in systolic function, even among patients with AF recurrence, may be related to a reduction in overall AF burden following PVI. Future studies using continuous rhythm monitoring, such as implantable loop recorders, are needed to test this hypothesis.