In-hospital outcomes of atrial fibrillation catheter ablation in patients with baseline anemia or thrombocytopenia: a nationwide analysis from the National Inpatient Sample (2016–2021)

Background/Introduction Catheter ablation is a cornerstone therapy for symptomatic atrial fibrillation (AF), but data on its safety in patients with hematologic disorders such as anemia or thrombocytopenia remain limited to small studies. These conditions may increase periprocedural bleeding and complication risks. Purpose To evaluate the prevalence and in-hospital outcomes of AF catheter ablation in patients with baseline anemia or thrombocytopenia using a large, real-world U.S. database. Methods We conducted a retrospective analysis of the National Inpatient Sample (NIS) database from 2016 to 2021. Adult patients undergoing AF catheter ablation were identified using ICD-10 procedure codes. Baseline sociodemographic and clinical characteristics, including CHA2DS2-VASc and ATRIA bleeding scores, were compared between patients with versus without baseline anemia or thrombocytopenia (ICD-10 diagnosis codes). In-hospital complications and mortality were assessed. Results An estimated 42,600 AF catheter ablation procedures were performed during the study period. Of these, 3,855 (~9%) occurred in patients with baseline anemia and 685 (1.6%) in those with baseline thrombocytopenia. Patients with anemia or thrombocytopenia were older and had higher CHA2DS2-VASc and ATRIA bleeding scores compared to those without these conditions. Overall complication rates were significantly higher in thrombocytopenic (25%) and anemic (17%) patients than in those without (8%; p<0.001). In thrombocytopenic patients, complications were driven by respiratory (10%), vascular (14%), and pericardial (12%) events. In anemic patients, vascular complications and need for hemodialysis predominated (8% and 7%, respectively). In-hospital mortality did not differ significantly across groups. Conclusions In this large nationwide registry, AF catheter ablation in patients with baseline anemia or thrombocytopenia was associated with markedly higher rates of in-hospital complications, particularly vascular, respiratory, and pericardial events. Pre-procedural optimization of hematologic parameters should be considered to potentially mitigate risks and improve safety in this vulnerable population.