Abstract Body (Do not enter title and authors here): Background
Patients with peripheral artery disease (PAD) and coronary artery disease (CAD) are at high risk for adverse cardiovascular events. Prior research shows worse clinical outcomes for these patients, but contemporary in-hospital outcomes for PAD patients hospitalized with acute myocardial infarction (AMI) are not well characterized.

Objectives
The objective of this study was to characterize in-hospital mortality and major bleeding events in PAD patients hospitalized with AMI in the U.S. We hypothesized that patients with PAD have higher rates of bleeding and mortality during AMI hospitalization.

Methods
We assessed characteristics, major bleeding, and mortality of AMI patients with PAD, defined as atherosclerotic disease in peripheral arteries, at 670 hospitals in the NCDR Chest Pain MI Registry between January 01, 2019 and March 31, 2023. Primary endpoints were in-hospital mortality and major bleeding. Exploratory endpoints included cardiac arrest, cardiogenic shock, heart failure, stroke, and new dialysis requirement.

Results
Of 493,740 patients, 36,274 (7.4%) had PAD. These patients were older with higher prevalences of comorbidities. In-hospital mortality was 8.2% for patients with PAD vs. 4.9% for those without PAD, while major bleeding occurred in 9.7% of patients with PAD and 6.3% of those without PAD. After multivariable adjustment, PAD was associated with increased mortality (aOR 1.25; 95% CI 1.19 to 1.31) and major bleeding (aOR 1.23; 95% CI 1.17 to 1.28). The elevated risk of in-hospital mortality was driven by patients with PAD who were 65 years of age or older (aOR 1.29; 95% CI 1.22 to 1.37), whereas no significant difference was observed in patients younger than 65 years (aOR 1.00; 95% CI 0.91 to 1.09). No significant interactions for mortality risk were observed based on sex (p=0.98) or race (p=0.84). For major bleeding, no significant interactions were observed based on age (p=0.41), sex (p=0.84), or race (p=0.27). Exploratory endpoints showed poorer outcomes in PAD vs. non-PAD patients regarding cardiac arrest (6.4% vs. 4.6%), cardiogenic shock (6.9% vs. 4.8%), heart failure (2.5% vs. 1.0%), stroke (1.4% vs. 0.9%), and new dialysis requirement (2.5% vs. 1.0%).

Conclusions
This large, nationally representative study demonstrates that PAD patients hospitalized for AMI are at increased risk for in-hospital mortality and major bleeding compared to patients without PAD. Improved management strategies in the acute care setting are needed.