Efficacy of alcohol septal ablation in mildly symptomatic or severely symptomatic patients with hypertrophic obstructive cardiomyopathy / 中华心血管病杂志

Objective: To compare the prognosis of mildly or severely symptomatic patients with obstructive hypertrophic cardiomyopathy (OHCM) who underwent alcohol septal ablation (ASA). Methods: This retrospective study cohort consisted of patients with OHCM who received ASA treatment in Beijing Anzhen Hospital, Capital Medical University from March 2001 to August 2021. These patients were divided into mildly and severely symptomatic groups according to the severity of clinical symptoms. Long-term follow-up was conducted, and the following data were collected: duration of follow-up, postoperatire treatment, New York Heart Association (NYHA) classification, arrhythmia events and pacemaker implantation, echocardiographic parameters, and cause of death. Overall survival and survival free from OHCM-related death were observed, and the improvement of clinical symptoms and resting left ventricular outflow tract gradient (LVOTG) and the incidence of new-onset atrial fibrillation were evaluated. The Kaplan-Meier method and log-rank test were used to determine and compare the cumulative survival rates of the different groups. Cox regression analysis models were used to determine predictors of clinical events. Results: A total of 189 OHCM patients were included in this study, including 68 in the mildly symptomatic group and 121 in the severely symptomatic group. The median follow-up of the study was 6.0 (2.7, 10.6) years. There was no statistical difference in overall survival between the mildly symptomatic group (5-year and 10-year overall survival were 97.0% and 94.4%, respectively) and the severely symptomatic group (5-year and 10-year overall survival were 94.2% and 83.9%, respectively, P=0.405); there was also no statistical difference in survival free from OHCM-related death between the mildly symptomatic group (5-year and 10-year survival free from HCM-related death were 97.0% and 94.4%, respectively) and the severely symptomatic group (5-year and 10-year survival free from HCM-related death were 95.2% and 92.6%, respectively, P=0.846). In the mildly symptomatic group, NYHA classification was improved after ASA (P<0.001), among which 37 patients (54.4%) were in NYHA class Ⅰ, and the resting left ventricular outflow tract gradient (LVOTG) decreased from 67.6 (42.7, 90.1) mmHg (1 mmHg=0.133 kPa) to 24.4 (11.7, 35.6) mmHg (P<0.001). In severely symptomatic group, NYHA classification was also improved post ASA (P<0.001), among which 96 patients (79.3%) improved by at least one NYHA classification, and the resting LVOTG decreased from 69.6 (38.4, 96.1) mmHg to 19.0 (10.6, 39.8) mmHg (P<0.001). The incidence of new-onset atrial fibrillation was similar between the mildly and severely symptomatic groups (10.2% vs. 13.3%, P=0.565). Cox multivariate regression analysis showed that age was an independent predictor of all-cause mortality in OHCM patients post ASA (HR=1.068, 95%CI 1.002-1.139, P=0.042). Conclusions: Among patients with OHCM treated with ASA, overall survival and survival free from HCM-related death were similar between mildly symptomatic group and severely symptomatic group. ASA therapy can effectively relieve resting LVOTG and improve clinical symptoms in mildly or severely symptomatic patients with OHCM. Age was an independent predictor of all-cause mortality in OHCM patients post ASA.

Therapeutic effects of alcohol septal ablation in mildly symptomatic patients with hypertrophic obstructive cardiomyopathy / 中华心血管病杂志

Objective: To observe the therapeutic effects of alcohol septal ablation (ASA) in mildly symptomatic patients (NYHA class Ⅱ) with hypertrophic obstructive cardiomyopathy(HOCM). Methods: This retrospective study included 150 mildly symptomatic patients with HOCM hospitalized in Beijing Anzhen Hospital affiliated to Capital Medical University from March 2001 to December 2017, consisting of medical therapy group (n=102) and ASA group (n=48). Baseline clinical data were collected, patients were followed up to a mean of 6.0 (3.5, 8.1) years. Overall and HCM-related mortality events (including chronic heart failure, atrial fibrillation related stroke, sudden cardiac death) were observed in the two groups. Moreover, the improvement of NYHA function classification and left ventricular outflow tract gradient (LVOTG) were also evaluated. Survival analysis was performed by Kaplan-Meier method. Results: Age of this cohort was (52.9±14.5)years, 92 cases(61.3%) were male. In the follow-up, LVOTG was reduced from (85.8±35.4)mmHg (1 mmHg=0.133 kPa) to (27.7±19.8)mmHg (P<0.001) in the ASA group, and from (66.3±35.0)mmHg to (56.5±27.7)mmHg in medical therapy group(P<0.01). At the last clinical follow-up, there were 32 patients (66.7%) whose LVOTG were<30 mmHg, septal thickness decreased from (20.3±3.8)mm to (16.1±3.4)mm (P<0.001), NYHA classification was also remarkably improved (P<0.001). New-onset atrial fibrillation tended to be lower in the ASA group compared to medical therapy group (9.3%(4/43) vs. 20.8%(20/96),P=0.096). Eleven patients (10.8%) in the medical therapy group and 2 patients (4.2%) in the ASA group died during the follow-up. One patient received pacemaker during the peri-procedural period, 1 patient was implanted with two-chamber pacemaker due to Ⅲ° atrioventricular block at 10 years after operation in the ASA group. Survival free of all-cause mortality of ASA group at 5 and 10 years was 97.9% and 97.9%, respectively, which was comparable to the medical therapy group (P=0.231). Survival free of HCM-related mortality was similar between the two groups (P=0.397). Conclusions: Compared with medical therapy in mildly symptomatic patients with HOCM, long-term survival rate is similar after ASA. Meanwhile, ASA can remarkably reduce LVOTG and improve the clinical status of the patients. Therefore, ASA may be used as an alternative therapy for mildly symptomatic HOCM patients.