Abstract 4142134: Temporal Trends in Implantation of Cardiac Electronic Devices Following Septal Reduction Therapy in Obstructive Hypertrophic Cardiomyopathy

Background: Septal reduction therapy (SRT) options for obstructive hypertrophic cardiomyopathy (oHCM) include surgical myectomy (SM) and alcohol septal ablation (ASA). A significant proportion of these SRTs also concurrently receive an implantable cardioverter defibrillator (ICD). We aimed to compare recent temporal trends and outcomes in this SRT subset. Methods: National Inpatient Sample 2016-2021 was queried to identify adults with oHCM using appropriate ICD codes and procedure codes were obtained for SM with ICD placement and ASA with ICD placement respectively. Logistic regression was applied to compare in-hospital outcomes. Results: Between 2016-2021, there were 420 cases with SM and ICD placement and 185 cases with ASA and ICD placement. Cases with ASA with ICD were older (64.3 -vs- 52.4 years), more likely to be females (58.3% -vs- 40.3%, p=0.041). The proportion of annual SM with ICD placement rates continued to decrease from 2016 and 2021 (Table 1). In comparison to this, there was an increase in ASA with ICD placement rates each year. During the study period, a majority of ASA with ICD occurred in the northeast while the majority of SM with ICD occurred in the midwest. More than 90% of SRTs were performed at large urban teaching centers. ASA with ICD cases had a higher proportion of SRT complications including development of complete heart block (62.2% -vs- 41.7%, p<0.001) but lower incidence of ventricular fibrillation (2.7% -vs-9.5%, p=0.003). ASA with ICD cases had a shorter length of stay (6.6 -vs- 10.9 days) and less total hospitalization cost ($240,792 -vs- $314,359). For both groups, major complications were uncommon and remained unchanged throughout this study period. Conclusion: Analysis of SRT groups in this retrospective database of hospital admissions was indicative of an overall decline in SM with ICD procedures from 2016 to 2021. Further analysis is needed to understand the impact of this trend on long term outcomes of oHCM patients.