Outcomes of Alcohol Septal Ablation in Patients With Severe Left Ventricular Outflow Tract Obstruction: A Propensity Score Matching Analysis.

BACKGROUND: The current ACC/AHA guidelines on hypertrophic cardiomyopathy (HCM) caution that alcohol septal ablation (ASA) might be less effective in patients with left ventricular outflow tract obstruction (LVOTO) ≥ 100 mm Hg. METHODS: We used a multinational registry to evaluate the outcome of ASA patients according to baseline LVOTO. RESULTS: A total of 1346 ASA patients were enrolled and followed for 5.8 ± 4.7 years (7764 patient-years). The patients with baseline LVOTO ≥ 100 mm Hg were significantly older (61 ± 14 years vs 57 ± 13 years; P < 0.01), more often women (60% vs 45%; P < 0.01), and had a more pronounced HCM phenotype than those with baseline LVOTO < 100 mm Hg. There were no significant differences in the occurrences of 30-day major cardiovascular adverse events in the 2 groups. After propensity score matching (2 groups, 257 pairs of patients), the long-term survival was similar in both groups (P = 0.10), the relative reduction of LVOTO was higher in the group with baseline LVOTO ≥ 100 mm Hg (82 ± 21% vs 73 ± 26%; P < 0.01), but the residual resting LVOTO remained higher in this group (23 ± 29 mm Hg vs 13 ± 13 mm Hg; P < 0.01). Dyspnoea (NYHA functional class) at the most recent clinical check-up was similar in the 2 groups (1.7 ± 0.7 vs 1.7 ± 0.7; P = 0.85), and patients with baseline LVOTO ≥ 100 mm Hg underwent more reinterventions (P = 0.02). CONCLUSIONS: After propensity matching, ASA patients with baseline LVOTO ≥ 100 mm Hg had similar survival and dyspnoea as patients with baseline LVOTO < 100 mm Hg, but their residual LVOTO and risk of repeated procedures were higher.

Outcomes of Patients With Hypertrophic Obstructive Cardiomyopathy and Pacemaker Implanted After Alcohol Septal Ablation.

BACKGROUND: Atrioventricular block is a frequent major complication after alcohol septal ablation (ASA). OBJECTIVES: The aim of this study was to evaluate the outcomes of patients with implanted permanent pacemaker (PPM) related to a high-grade atrioventricular block after ASA for hypertrophic obstructive cardiomyopathy. METHODS: We used a multinational registry (the Euro-ASA registry) to evaluate the outcome of patients with PPM after ASA. RESULTS: A total of 1,814 patients were enrolled and followed up for 5.0 ± 4.3 years (median = 4.0 years). A total of 170 (9.4%) patients underwent PPM implantation during the first 30 days after ASA. Using propensity score matching, 139 pairs (n = 278) constituted the matched PPM and non-PPM groups. Between the matched groups, there were no long-term differences in New York Heart Association functional class (1.5 ± 0.7 vs 1.5 ± 0.9, P = 0.99) and survival (log-rank P = 0.47). Patients in the matched PPM group had lower long-term left ventricular (LV) outflow gradient (12 ± 12 mm Hg vs 17 ± 19 mm Hg, P < 0.01), more pronounced LV outflow gradient decrease (81% ± 17% vs 72% ± 35%, P < 0.01), and lower LV ejection fraction (64% ± 8% vs 66% ± 8%, P = 0.02) and were less likely to undergo reintervention (re-ASA or myectomy) (log-rank P = 0.02). CONCLUSIONS: Patients with hypertrophic obstructive cardiomyopathy treated with ASA have a 9% probability of PPM implantation within 30 days after ASA. In long-term follow-up, patients with PPM had similar long-term survival and New York Heart Association functional class but lower LV outflow gradient, a more pronounced LV outflow gradient decrease, a lower LV ejection fraction, and a lower likelihood of reintervention compared with patients without PPM.

Prediction of Sudden Cardiac Arrest After Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy: ASA-SCARRE Risk Score.

This study aimed to derive a new score, the Alcohol Septal Ablation-Sudden Cardiac ARREst (ASA-SCARRE) risk score, that can be easily used to evaluate the risk of sudden cardiac arrest events (sudden cardiac death, resuscitation, or appropriate implantable cardioverter-defibrillator discharge) after alcohol septal ablation (ASA) in patients with hypertrophic obstructive cardiomyopathy. We analyzed 1,834 patients from the Euro-ASA registry (49% men, mean age 57 ± 14 years) who were followed up for 5.0 ± 4.3 years (9,202 patient-years) after ASA. A total of 65 patients (3.5%) experienced sudden cardiac arrest events, translating to 0.72 events per 100 patient-years. The independent predictors of sudden cardiac arrest events were septum thickness before ASA (hazard ratio 1.09 per 1 mm, 95% confidence interval 1.04 to 1.14, p <0.001) and left ventricular outflow tract (LVOT) gradient at the last clinical checkup (hazard ratio 1.01 per 1 mm Hg, 95% confidence interval 1.01 to 1.02, p = 0.002). The following ASA-SCARRE risk scores were derived and independently predicted long-term risk of sudden cardiac arrest events: "0" for both LVOT gradient <30 mmHg and baseline septum thickness <20 mm; "1" for LVOT gradient ≥30 mm Hg or baseline septum thickness ≥20 mm; and "2" for both LVOT gradient ≥30 mm Hg and baseline septum thickness ≥20 mm. The C statistic of the ASA-SCARRE risk score was 0.684 (SE 0.030). In conclusion, the ASA-SCARRE risk score may be a useful and easily available clinical tool to predict risk of sudden cardiac arrest events after ASA in patients with hypertrophic obstructive cardiomyopathy.