Background Acute pericarditis (AP) is considered a cardiovascular complication in patients with COVID-19. We aimed to ass-ess the incidence, associated complications, and clinical impact of AP on hospitalized patients with COVID-19. Methods and Results In this retrospective cohort study, International Classification of Diseases, Tenthth Revision, Clinical Modification (ICD-10) codes were used to identify patients with COVID-19 with or without AP in the National Inpatient Sample 2020 database. We compared outcomes between AP and non-AP groups before and after propensity-score matching for patient and hospital demographics and relevant comorbidities. A total of 211 619 patients with a primary diagnosis of COVID-19 were identified, including 983 (0.46%) patients who had a secondary diagnosis of AP. Before matching, patients with COVID-19 with AP were younger (59.93±19.24 years old versus 64.29±16.82 years old) and more likely to have anemia (40.5% versus 19.9%), cancer (6.7% versus 3.6%), and chronic kidney disease (29.3% versus 19.6%) (all P<0.05). After matching, patients with COVID-19 with AP (n=980), when compared with the matched non-AP group (n=2936), had higher rates of mortality (21.3% versus 11.1%, P<0.001), cardiac arrest (5.0% versus 2.6%, P<0.001), cardiogenic shock (4.2% versus 0.5%, P<0.001), ventricular arrhythmia (4.7% versus 1.9%, P<0.001), acute kidney injury (38.3% versus 28.9%, P<0.001), acute congestive heart failure (14.3% versus 4.8%, P<0.001), and longer length of stay (7.00±10.00 days versus 5.00±7.00 days, P<0.001) and higher total charges ($75066.5±$130831.3 versus $44824.0±$63660.5, P<0.001). Conclusions In hospitalized patients with COVID-19, AP is a rare but severe in-hospital complication and is associated with worse in-hospital outcomes.
Keywords: COVID‐19; acute pericarditis; in‐hospital complications; mortality.