Comparison of in-hospital outcomes of patients undergoing catheter ablation for typical versus atypical atrial flutter.

Background: Catheter ablation (CA) is indicated as definitive therapy for patients with either typical or atypical atrial flutter (TAFlutter and AAFlutter, respectively) which is unresponsive to medical therapy. There is a paucity of data regarding in-hospital outcomes of patients undergoing CA.

Methods: Retrospective study using the NIS to identify patients ≥18 years who underwent CA between 2015 and 2017. Individuals were identified using ICD-10-CM/PCS for TAFlutter, AAFlutter, and CA.

Results: A total of 17,390 patients underwent CA for Aflutter (33% AAFlutter and 67% TAFlutter). The TAFlutter group was younger (mean 65.9 years vs. 67.2 years), with less females (30% vs. 43%, p ≤ 0.001 for both) compared to the AAFlutter group. The TAFlutter group had a higher rate of diabetes, tobacco use, obesity, and chronic obstructive pulmonary disease (p ≤ 0.001 for all). The AAFlutter cohort had increased prior strokes and atrial fibrillation (p ≤ 0.001 for both). The mean CHADS-VASc score was found to be 2.3 in AAFlutter compared to 2.1 in TAFlutter (p ≤ 0.001). There were significantly higher proportions of thromboembolic events, transfusions, and longer length of stay in the TAFlutter group (p ≤ 0.001 for all) with the AAFlutter group having significantly higher rates of cardioversion, implantation of cardiac devices, and increased hospital charges (p ≤ 0.001 for all); no significant difference was found in mortality after controlling for comorbidities.

Conclusions: We found higher complication rates in CA for patients with TAFlutter, but no difference in in-hospital all-cause mortality. Variation in CA depending upon the mechanism of AFlutter may underlie these differences, and warrant further study.