Abstract 12473: Seasonal Differences In Management And Outcomes Of Cardiac Arrest Complicating Acute Myocardial Infarction

Introduction: The role of seasons in the outcomes and management of acute myocardial infarction (AMI) patients with cardiac arrest (CA) remains understudied. Methods: We used the National Inpatient Sample (2000-2017) to identify adults AMI admissions with concomitant CA. Admission month was used to classify them into- Spring (March-May), Summer (June-August), Fall (September-November) and Winter (December-February) admissions. We evaluated seasonal variation in the prevalence of CA among AMI admissions and associated in-hospital mortality. Use of cardiac and non-cardiac procedures, hospital length of stay, hospitalization costs and discharge disposition were also analyzed. Results: Between 2000-2017, of the 10,880,856 AMI admissions with information on admission month available, CA was identified in 546,334 (5.0%). Incidence of CA was 4.9% in spring, 5.0% in summer, 5.1% in fall, and 5.1% in winter AMI admissions. Adjusted trends identified a steady increase in STEMI-CA admissions with a relatively stable or declining trend for NSTEMI-CA admissions across all seasons. AMI-CA admissions admitted in summer were less often female, had lower comorbidity, more often presented with STEMI and had higher rates of cardiogenic shock and shockable rhythms compared to AMI-CA admissions in spring, fall and winter. Compared to AMI-CA admissions in other seasons, those admitted in winter had slightly lower rates of coronary angiography (61.4% vs. 63.3%-64.3%) and PCI (45.6% vs. 47.2-48.4%) (p<0.001). Compared to those admitted in the spring, adjusted in-hospital mortality was higher for winter (OR 1.08 [95% CI 1.06-1.10]; p<0.001), lower for summer (OR 0.96 [95% CI 0.94-0.98]; p<0.001) and comparable for fall (OR 1.00 [95% CI 0.98-1.02]; p=0.91) AMI-CA admissions. Length of hospital stay, total hospitalization charges, and discharge dispositions for AMI-CA admissions were comparable across the seasons. Conclusions: Lower use of guideline directed therapies and higher in-hospital mortality was identified in winter AMI-CA hospitalizations. The role of pathobiology and/or impact of environmental conditions across seasons in AMI-CA remains to be evaluated.