Symptoms-to-emergency-call timing delay in acute coronary syndrome before and during COVID-19: independent predictors and their impact on mortality

Background: The COVID-19 pandemic severely impacted global health. The aim of this study was to compare predictors of symptoms-to-emergency-call timing delay in Acute Coronary Syndrome (ACS) and their impact on mortality before and during the COVID-19 outbreak. Methods: We collected sociodemographic, clinical data, procedural features, pre-admission and intra-hospital outcomes of consecutive patients admitted for ACS in seventeen Italian centers from March to April 2018, 2019, and 2020. Results: In 2020, a 32.92% reduction in ACS admissions was observed compared to 2018 and 2019. Unstable angina, typical and atypical symptoms, and intermittent angina were identified as significant predictors of symptoms-to-emergency-call timing delay before and during the COVID-19 pandemic (p<0.005 for all the items). Differently from 2018-2019, during the pandemic, hypertension and dyspnea (p=0.002 versus [vs] p=0.490 and p=0.001 vs p=0.761 for 2018-2019 and 2020, respectively) did not result as predictors of delay in symptoms-to-emergency-call timing. Among these predictors, only the atypical symptoms (HR 3.36; 95% CI 1.172 - 9.667, p=0.024) in 2020 and the dyspnea (HR 2.64; 95% CI 1.345 - 5.190, p=0.005) in 2018-2019 resulted significantly associated with higher mortality. Finally, the family attendance at the onset of the symptoms resulted in a reduction in symptoms-to-emergency-call timing (in 2020 p<0.001; CI -1710.73; -493.19) and in a trend of reduced mortality (HR 0.31; 95% CI 0.089 - 1.079, p=0.066) in 2020. Conclusions: During the COVID-19 outbreak, atypical symptoms and family attendance at ACS onset were identified, respectively, as adverse and favorable predictors of symptoms-to-emergencycall timing delay and mortality.