Background: Prior diagnosis of heart failure (HF) is associated with increased length of hospital stay (LOS) and mortality from Coronavirus disease-2019 (COVID-19). Associations between substance use, venous thromboembolism (VTE), or peripheral arterial disease (PAD) and its effects on LOS or mortality in patients with HF hospitalized with COVID-19 remains unknown .

Objective: This study identified risk factors associated with poor in-hospital outcomes among patients with HF hospitalized with COVID-19 .

Methods: Case control study was conducted of patients with prior diagnosis of HF hospitalized with COVID-19 at an academic tertiary care center from January 1 , 2020 to February 28 , 2021 . Patients with HF hospitalized with COVID-19 with risk factors were compared with those without risk factors for clinical characteristics, length of stay (LOS), and mortality . Multivariate regression was conducted to identify multiple predictors of increased LOS and in-hospital mortality in patients with HF hospitalized with COVID-19.

Results: Total of 211 HF patients were hospitalized with COVID-19 . Females had longer LOS than males (9 days vs. 7 days; p <0.001). Compared with patients without peripheral arterial disease (PAD) or ischemic stroke, patients with PAD or ischemic stroke had longer LOS (7 days vs. 9 days; p = 0.012 and 7 days vs. 11 days, p <0.001; respectively). Older patients (aged 65 and above) had increased in-hospital mortality compared to younger patients (Adjusted OR : 1.04; 95% CI : 1.00-1.07; p = 0.036). VTE increased mortality more than three-fold in patients with HF hospitalized with COVID-19 (Adjusted OR : 3.33; 95% CI : 1.29-8.43; p = 0.011). Conclusion: Vascular diseases increase LOS and mortality in patients with HF hospitalized with COVID-19.