Impact of more than mild mitral regurgitation on clinical profile and outcomes in patients with heart failure
S Humanes Ybanez, A Fraile Sanz, M De La Serna, P Rodriguez, N Gil, M Gutierrez Munoz, E Parrales, A Vilchez, R Mata Caballero, M Martin Munoz, M Alvarez Bello, C Utrilla, I Miralles, J Perea Ejido, J J Alonso MartinAbstract
Background
Mitral regurgitation (MR) is frequently observed in patients with heart failure (HF) and reflects advanced structural heart disease. Beyond its prognostic implications, more than mild MR may identify patients with a distinct clinical and haemodynamic profile.
Purpose
To compare clinical characteristics, echocardiographic findings, and outcomes between patients hospitalized for HF with more than mild MR and those with mild or no MR.
Methods
We conducted a retrospective analysis of consecutive patients hospitalized for HF between 2020 and 2025. Patients were stratified according to the presence of more than mild MR on transthoracic echocardiography. Clinical data, echocardiographic parameters, biomarkers, treatment, and outcomes were compared. Median follow-up was 11 months (IQR 10–12).
Results
Among 445 patients included, 132 (30%) presented with more than mild mitral regurgitation. Compared with patients with mild or no mitral regurgitation, those with significant mitral regurgitation more frequently had a prior history of heart failure (48% vs. 37%, p=0.042) and presented with greater haemodynamic compromise, including higher rates of low cardiac output (18% vs. 5%, p<0.001) and need for vasoactive support (12% vs. 5%, p=0.003). Patients with more than mild mitral regurgitation also showed a higher prevalence of left bundle branch block and a distinct echocardiographic phenotype characterized by lower left ventricular ejection fraction (35% vs. 46%, p<0.001) and greater left ventricular dilation. Despite a lower prevalence of clinically overt right-sided heart failure (35% vs. 47%, p=0.018), markers of right-sided involvement were more frequently observed in patients with more than mild mitral regurgitation, including right ventricular dysfunction (38% vs. 24%, p=0.002), pulmonary hypertension (68% vs. 45%, p<0.001), and significant tricuspid regurgitation (16% vs. 8%, p=0.008). Indices of diastolic function suggested higher left ventricular filling pressures, with higher mitral inflow velocities and E/A ratio, while E/e′ ratio did not differ significantly between groups. Natriuretic peptide levels at admission and discharge were significantly higher in patients with more than mild mitral regurgitation. Device therapy, including implantable cardioverter-defibrillator and cardiac resynchronization therapy, was more frequently used in this group. Time to heart failure readmission was significantly shorter in patients with more than mild mitral regurgitation, while cardiovascular mortality during follow-up was similar between groups.
Conclusion
In a real-world HF population, more than mild MR identifies a more advanced phenotype with greater haemodynamic compromise and biventricular involvement. Earlier HF readmission highlights the clinical relevance of MR for risk stratification during HF hospitalizationTable 1.Patients with and without MRFor image description, please refer to the figure legend and surrounding text.