BMC Cardiovasc Disord. 2026 Oct 31;26(1):1006. doi: 10.1186/s12872-026-06952-w.
ABSTRACT
BACKGROUND: The primary mechanism of mitral regurgitation (MR) in hypertrophic obstructive cardiomyopathy is systolic anterior motion (SAM) of the mitral leaflets due to septal hypertrophy narrowing the left ventricular outflow tract (LVOT), influencing leaflet movement and closure. Among patients undergoing alcohol septal ablation (ASA), the impact on- and underlying mechanism of MR remains less studied. The aim was to determine the prevalence of MR and changes in MR severity after ASA and analyze echocardiographic (ECHO) parameters associated with MR changes.
METHODS: All patients who underwent ASA at Karolinska University Hospital in Sweden, 2009-2021 (follow-up until 2025), were included in this retrospective cohort study. ECHO parameters were collected before ASA, at 1-year follow-up and at the latest follow-up registered. To evaluate differences in continuous values, Kruskal-Wallis test was used, and for categorical values, Fischer's exact test was used.
RESULTS: 154 patients were included (mean follow-up 4.0 ± 3.9 years). 14% (n = 21) had at least moderate MR at baseline, of which 90% (n = 19) improved to mild MR or less. The patients with improved (n = 19, 12%) or unchanged (n = 128, 83%) grade of MR showed greater reduction of LVOT peak pressure gradients (improved MR: 137.5 to 4.8 mmHg, unchanged MR: 57.0 to 25.0 mmHg) between baseline and last follow-up, compared with patients with increased MR grade (n = 7, 4.5%, 57.0 to 51.0 mmHg, p = 0.003).
CONCLUSIONS: Among patients with at least moderate MR before ASA, MR severity generally improved at follow-up, potentially due to septal reduction and LVOT enlargement, which may have reduced SAM.
CLINICAL TRIAL NUMBER: Not applicable.
PMID:42966866 | DOI:10.1186/s12872-026-06952-w