Abstract 15958: Comparison of In-hospital Outcomes of Patients Undergoing Catheter Ablation for Typical versus Atypical Atrial Flutter

Introduction: Catheter Ablation (CA) is indicated as definitive therapy for patients with atrial flutter (AF) which is unresponsive to medical therapy. While atrial flutter may be typical (TAF) or atypical (AAF), there is a paucity of data regarding in-hospital outcomes of patients undergoing CA. Methods: This retrospective cohort study used the Nationwide Inpatient Sample to identify all patients above 18 years who underwent CA between 2015 and 2017. Individuals were identified using ICD-10-CM/PCS for TAF, AAF and CA. Statistical analysis was performed comparing TAF to AAF. Results: A total of 17,390 patients underwent CA for AF, with 33% having AAF and 67% TAF. Patients with TAF were younger (median 67 years vs. 68 years), with lower proportion of females (29.6% vs. 42.8% p≤0.05 for both) compared to patients with AAF. TAF group had higher rates of emergent admission (85.7% vs. 65.5% p≤0.05). Interestingly, subjects with AAF had earlier interventions than patients with TAF (≤3 days of admission, 76.4% vs. 71% p≤0.05). Patients with TAF have a higher rate of hypertension, diabetes, smoking, heart failure, liver disease, and chronic obstructive pulmonary disease (p≤0.05 for all). However, patients with AAF had increased prior strokes and percutaneous coronary interventions (PCI) (p≤0.05 for both). The mean CHA2DS2-VASc score was found to be 2.3 in AAF compared to 2.1 in TAF (controlled for comorbidities, p≤0.05). Multivariable regression showed a significantly higher proportion of cardiogenic shock, acute coronary syndrome, sepsis, cardiac catheterization, PCI, thromboembolism event, transfusion, and longer length of stay in patients with TAF (p≤0.05 for all). Although we found that patients with AAF have significant higher rates of cardioversion, implantation of cardiac device, pericardial complications, and increased hospital charges (p≤0.05 for all), no significant difference was found in mortality. Conclusion: In this retrospective cohort study, we found higher complication rates in CA of patients with TAF, even when adjusting for pertinent comorbidities, but no difference in in-hospital all-cause mortality. Variation in CA depending upon the mechanism of AF may underlie these differences, and warrant further study.