Background: African Americans have a lower incidence of atrial arrhythmias, both atrial fibrillation (AF) and atrial flutter (AFL), despite a greater number of traditional risk factors. The incidence of AF after cavotricuspid isthmus (CTI) ablation in patients with typical AFL is markedly increased, approaching 40% in some studies. It is unknown if African Americans specifically have a similar rate of increased AF after CTI ablation for typical AFL. We sought to identify differences in development of AF after CTI ablation for typical AFL with regards to race, between African American and non- African Americans. The hypothesis is that African Americans will have a lower incidence of AF after CTI ablation for typical AFL. Methods: The electronic medical records of first time, successful CTI ablations performed for typical AFL were retrospectively reviewed over a 48 month period. Clinical variables were retrieved from the EMR. AFL was documented on ECG, Holter/ event monitor or device interrogation at clinical follow up visits. Follow up was obtained over a 1 year period. Patients were self-identified as African American, White, Hispanic or Other. Results: The records of a total of 201 patients - 51 African Americans (25.4%) and 150 non-African Americans (74.6%) - who underwent CTI ablation for typical AFL were examined. Average age was similar (67.8 vs 66.3, p=NS) with a preponderance of men (77.6% vs 23.5%). There was a significantly lower rate of development of AF post CTI ablation for typical AFL in African Americans vs non-African Americans (22.2% vs 46.6%, p=0.002). Additionally, women were more likely to develop AF (53.1% vs 36.2%, p=0.026). African American men were the least likely to develop AF post AFL ablation (p=0.0062). Conclusions: We observed a significantly lower incidence of AF among African American patients after CTI ablation for typical AFL.