Basal infarct location but not larger infarct size is associated with a successful outcome after alcohol septal ablation in patients with hypertrophic obstructive cardiomyopathy: a cardiovascular magnetic resonance imaging study

Comparative Evaluation of Alcohol Septal Ablation: Left Anterior Descending Versus Non-left Anterior Descending Artery Approaches

Alcohol septal ablation (ASA) is performed for symptomatic drug-refractory hypertrophic obstructive cardiomyopathy to reduce the left ventricular outflow tract pressure gradient (LVOTPG) by injecting ethanol into a septal branch that perforates the septal bulge. The target septal branches usually arise directly from the left anterior descending (LAD) artery; however, vessels from a non-LAD artery can be selected in some cases. This study aimed to compare the effectiveness and safety between ASA performed using a septal branch arising from a non-LAD artery and a branch arising from the LAD artery. This single-center, retrospective, observational cohort study comprised patients with hypertrophic obstructive cardiomyopathy who underwent ASA at the Gifu Heart Centre between 2011 and 2022. The effectiveness and safety of ASA using the 2 artery types were compared. The primary end points were LVOTPG and procedure success, determined as LVOTPG <30 mm Hg after 1 year. Of 33 patients (mean age 66.4 ± 13.0 years, 13 men), 18 patients who underwent ASA using only LAD branches and 15 patients who underwent ASA using only non-LAD branches demonstrated no significant difference in the decrease in LVOTPG during the follow-up period (-99.1 ± 47.4 mm Hg/year vs -75.7 ± 39.2 mm Hg/year, respectively, p = 0.19). The procedure success at 1 year was not significantly different between the 2 groups (93.3% and 84.6%, respectively, p = 0.58). ASA performed using septal branches from non-LAD arteries could be an alternative treatment approach when appropriate septal branches are missing or desirable effects cannot be obtained from ASA using LAD branches.

Usefulness of Non-Anteroseptal Region Left Ventricular Hypertrophy Using Cardiac Magnetic Resonance to Predict Repeat Alcohol Septal Ablation for Refractory Obstructive Hypertrophic Cardiomyopathy

We evaluated a cohort of patients treated with alcohol septal ablation (ASA) to identify predictive factors for repeat ASA. We compared 15 patients who underwent repeat ASA procedures (group R) with 69 patients not requiring repeat procedures (group S) in terms of clinical parameters and morphologic cardiac magnetic resonance. Group R showed higher number of hypertrophic segments (thickness ≥15 mm) in the basal left ventricular level (2.8 ± 1.7 vs 1.7 ± 0.8, p = 0.009) than group S. In the multivariate analysis, diuretics use (adjusted odds ratio 5.8, 95% confidential interval [CI] 1.04 to 32.2, p = 0.045) and the number of non-anteroseptal extended hypertrophy segments at the basal level were independent predictors of a repeat ASA procedure (adjusted odds ratio 3.64/segment, 95% CI 1.40 to 9.4, p = 0.008). One repeat ASA among 21 patients without non-anteroseptal hypertrophy and 1 repeat ASA among 29 patients without posteroseptal hypertrophy were observed; however, 7 of the 14 patients with ≥2 segments of non-anteroseptal hypertrophy received repeat ASA. In conclusion, cardiac magnetic resonance-based cross-sectional investigation elucidated non-anteroseptal hypertrophy (≥2 segments) to be a crucial predictor of repeat ASA. ASA is useful for patients with regional hypertrophy in the basal anteroseptal, but not posteroseptal region, and without heart failure requiring diuretics.