Atrial fibrillation status in patients with ACS and percutaneous coronary intervention

Abstract Background Patients with acute coronary syndrome (ACS) often develop atrial fibrillation (AF) as a comorbidity or complication. We investigated the impact of AF status on in-hospital mortality and complications in ACS patients who underwent percutaneous coronary intervention (PCI) using a recent large-scale nationwide dataset. Methods Using a nationwide claims-based dataset from 1022 hospitals in Japan between 2012 and 2017, hospitalized patients with ACS and PCI were identified and classified into three groups according to the AF status: no AF, prevalent AF before admission, and incident AF after admission. In-hospital mortality, complications, and medical costs were compared in crude and propensity-matched cohorts. Results In 273,828 hospitalized patients with ACS and PCI, prevalent AF and incident AF were observed in 5.2% and 1.7%, respectively; the AF rates increased over 5 years. There was a greater proportion of older patients and patients with comorbidities in AF patients. Prevalent and incident AF statuses were associated with worse crude outcomes and complications during hospitalization. In propensity-matched cohorts, incident AF was associated with higher in-hospital mortality rate, longer length of stay, higher direct costs, and higher rate of complications, including stroke and acute kidney injury, than prevalent AF. These outcomes did not change in each AF status over 5 years. Conclusions Prevalent and incident AFs in patients with ACS and PCI had deteriorating effects on in-hospital clinical outcomes, and particularly, incident AF was associated with worse adjusted outcomes and complications. Further efforts are necessary to improve the outcomes in an aging society where AF incidence is increasing.