LAUSR

Introduction: Extracorporeal membrane oxygenation (ECMO) is being increasingly used for acute support in patients with cardiogenic shock (CS). Data regarding the indications, outcomes, and readmissions in these patients from a nationally representative sample is lacking. Methods: A secondary analysis of the Nationwide Readmission Database for years 2016-2017 was performed. Patients who were admitted with a primary diagnosis of CS were identified using ICD-10, Clinical Modification codes and were sub-grouped into those with acute coronary syndrome (ACS) and without ACS (non-ACS). Any readmission within 30 days of discharge was considered for analysis. Results: A total of 6,126 patients with CS received ECMO support, among which 35% had concurrent acute coronary syndrome (ACS). Patients on ECMO who had ACS were significantly older (60.5±11 vs 45.1±11 years, p<0.001) compared to non-ACS patients. Time to ECMO placement was also significantly shorter in ACS patients (3.4±5 vs 6.9±15 days, p<0.001). There was no difference in complications during index admission including vascular complications and stroke among the two groups. The length of index hospitalization was longer in the non-ACS group (32.8±36 vs 19.6±22.9 days, p<0.001) whereas mortality was significantly higher in patients with ACS (58.21 vs 49.55%, p<0.001). Every decade increase in the age above 50 years significantly increased odds of mortality in the non-ACS group whereas in the ACS group, mortality increased significantly only when the age is over 70 years [HR 2.32, CI(1.35-3.99), p=0.002]. The rate of readmission among patients who survived to discharge was 18.2% (17.3% in ACS group vs 18.9% in non-ACS group, p=0.35). The most common primary causes of readmission were local complications from ECMO placement (7.65%), CHF, (6.5%), sepsis (6.5%), critical illness poly-myopathy/neuropathy (2.9%) and stroke (1.46%). The mortality during readmission was 8.2%. Conclusions: Only 1 in every 2 patients with CS on ECMO survives to discharge. Survival to discharge in these patients differs significantly according to the presence or absence of ACS. Among the patients who survive to discharge, 18% of patients are readmitted within 30 days.