LAUSR

Introduction: Contemporary in-hospital mortality rates for patients presenting with acute myocardial infarction (AMI) and cardiogenic shock (CS) remain as high as 50%. The impact of comorbid lower extremity peripheral artery disease (LE-PAD) is unknown. Hypothesis: LE-PAD is associated with higher morbidity and mortality in patients presenting with CS and AMI. Methods: Medicare beneficiaries hospitalized with CS related to AMI from 10/2015-6/2017 were identified. PAD status was defined by the inpatient billing codes present in the year prior to presentation. Outcomes included in-hospital mortality, amputation, peripheral revascularization, and 6-month mortality. Adjusted regression models were used to evaluate outcomes. A subgroup analysis included patients requiring mechanical circulatory support (MCS). Results: Among 45,144 patients, 5.9% (N=2,651) had LE-PAD. The average age was 77.8±7.9, 59.8% were male and 83.0% were white. Cumulative in-hospital mortality was 46.8%, with greater risk among LE-PAD patients (55.2% vs 46.3%; adjusted OR 1.52, 95% CI 1.39-1.65). LE-PAD patients also had greater adjusted risk of in-hospital amputation (1.5% vs 0.2%; OR 3.23, 95% CI: 2.16-4.83), peripheral revascularization rates (1.4% vs 0.4%; OR 1.54, 95% CI: 1.06-2.23), and 6-month mortality (43.2% vs 23.7%; HR 2.06, 95% CI: 1.80-2.35). MCS was less frequently utilized in LE-PAD (20.1% vs. 38.1%, p<0.01). Adjusted in-hospital mortality, amputation and peripheral revascularization rates were comparable between LE-PAD and non-LE-PAD patients who received MCS. Non-MCS LE-PAD patients had a 2.28 fold higher adjusted 6-month mortality compared with MCS LE-PAD patients (95% CI 1.60-3.11; Figure). Conclusions: Comorbid PAD is associated with worse limb outcomes and mortality among patients with AMI and CS. Although MCS was less likely to be used in LE-PAD patients, in-hospital mortality and limb complication rates were comparable to non-LE-PAD MCS patients.