Abstract 14365: In-Hospital Outcomes of Septal Myectomy versus Alcohol Septal Ablation for Hypertrophic Cardiomyopathy - An Update and Insights From the National Inpatient Sample

Abstract

Introduction: Septal Myectomy (SM) and Alcohol Septal Ablation (ASA) improve symptoms in patients with Hypertrophic Cardiomyopathy (HCM), however, outcomes data in this population is predominantly from specialized centers. Methods: The National Inpatient Database was queried from 2011- 2019 for relevant ICD-9 and -10 diagnostic and procedural codes. Baseline characteristics and in-hospital outcomes of patients with HCM who underwent SM vs. ASA were compared. A p-value <0.001 was considered statistically significant. Results: We identified 17,245 patients who underwent septal reduction therapies, of whom 62.5% underwent SM and 37.5% underwent ASA. Patients who underwent SM had higher all-cause mortality (OR:2.2 [1.7-2.9]), post procedure ischemic stroke (OR: 2.4 [1.8-3.2]), acute kidney injury (OR: 1.9 [1.7-2.2]), vascular complications (OR: 4 [2.8-5.7]), ventricular septal defect (OR: 4.6 [3.5-6.1]), aortic dissection/aneurysm (OR: 1.6 [1.3-2.1]), cardiogenic shock (OR: 2 [1.5-2.6]), sepsis (OR:5.2 [3.3-8.1]), and left bundle branch block (OR: 3.2 [2.8-3.7]) (p<0.001 for all), compared to ASA. Patients who underwent ASA had higher post procedure complete heart block (OR: 1.2 [1.1-1.4]), 2 nd -degree AV Block (OR: 2 [1.4-3]), right bundle branch block (OR: 6.4 [5.3-7.8]), ventricular tachycardia (OR:2 [1.8-2.3]), supraventricular tachycardia (OR: 1.4 [1.2-1.7]), and more commonly required pacemaker (OR: 1.4 [1.2-1.6]) or implantable cardioverter-defibrillator (OR: 1.3 [1.1-1.5]) (p<0.001 for all) insertion compared to SM. Conclusions: This nationwide analysis evidenced patients undergoing SM had higher in-hospital mortality and periprocedural complications compared to ASA, however, those undergoing ASA had higher post-procedure conduction abnormalities and pacemaker or ICD implantation. The implications of these findings warrant further investigation in regards to patient selection strategies for these therapies.