Background <p>Alcohol septal ablation (ASA) is a valuable treatment option for patients with symptomatic obstructive hypertrophic cardiomyopathy (oHCM). While generally safe, ASA can lead to conduction abnormalities, including complete atrioventricular block (CHB), potentially necessitating permanent pacemaker implantation. This study investigated the impact of post-procedural corticosteroid administration on the need for permanent pacemaker implantation in oHCM patients who developed complete heart block after ASA.</p> Methods <p>From a single-center cohort of 512 consecutive patients undergoing alcohol septal ablation (ASA) between 2005 and 2023, we retrospectively analyzed the 82 patients (16%) who developed complete atrioventricular (AV) block. Patients received either oral prednisolone (1&#xa0;mg/kg) for at least three days or no corticosteroid therapy at the discretion of the physician. The primary endpoint was the need for permanent pacemaker implantation during the index hospitalization.</p> Results <p>Permanent pacemaker implantation was required in 25 of the 82 patients (30.5%). The incidence of PPM implantation was significantly lower in the corticosteroid group (7 of 41 patients; 17.1%) compared to the no-corticosteroid group (18 of 41 patients; 43.9%; <i>p</i> = 0.008). After multivariable adjustment, corticosteroid use was independently associated with a significantly lower risk of pacemaker implantation (OR: 0.21, 95% CI: 0.07–0.66, <i>p</i> = 0.007).</p> Conclusion <p>In this retrospective analysis, post-procedural corticosteroid administration was associated with a significant reduction in the need for permanent pacemaker implantation in oHCM patients with CHB after ASA. Further research is needed to confirm these findings and establish optimal corticosteroid treatment protocols.</p> Graphical abstract <p></p>