Intermediate (One-Year) Outcomes of Cardiogenic Shock Patients Supported by ECMO Due to Decompensated Heart Failure and Acute Myocardial Infarction

Abstract

<h3>Purpose</h3> Cardiogenic shock patients who are supported by ECMO have high mortality and morbidity. We evaluated the 1-year outcomes in ECMO supported patients with decompensated heart failure (DHF) or acute myocardial infarction (AMI), including death, heart transplantation (HT), left ventricular assist device (LVAD) implantation as well as dependency on hemodialysis or ventilation. <h3>Methods</h3> Patients supported by ECMO due to DHF or AMI registered in the Spectrum Health ECMO registry were included in this study. Clinical, echocardiographic, laboratory and hemodynamic characteristics were obtained in all patients. Survival analysis using Kaplan-Meier curves for the combined outcome of death, heart transplantation (HT) and LVAD implantation were developed. These outcomes were compared between DHF and AMI patients. The frequency of renal replacement therapy or ventilator dependency on 1-year survivors was calculated. <h3>Results</h3> A total of 283 patients received ECMO, 228 due to DHF and 55 due to AMI. Of these, 22 patients received LVAD, and 1patient received HT. A total of 174 patients died (including 6 LVAD patients and 1 HT patient) within 1 year of ECMO. Patients with AMI had higher troponin (2.5 ng/dL (0.49 - 7.85) vs. 1.4 ng/dL (0.15 - 4.6), p=0.013), lower total bilirubin 0.65 mg/dL (0.4 - 1.12) vs. 0.8 mg/dL (0.5 - 1.6), p=0.025), higher ALT (117 IU (61- 225) vs. 48 IU (29 - 171), p = 0.003), lower creatinine (1.35 mg/dL ± 0.75 vs. 1.6 mg/dL ± 1.17, p=0.006), lower inotropic score (7 (1 - 18) vs. 9 (4 - 20), p=0.022). The combined endpoint survival free of HT or LVAD implantation at 1-month was 45.5% vs. 38.6% for AMI and DHF, respectively. There was a small but continued decrease in the survival of combined outcome at 1 year (36.4% vs. 32%, p=0.607, Figure 1). The 1-year survival probability free of the combined outcome for those patients who survived 30 days was 81.4% vs. 81.7% for AMI and DHF, respectively. Of the 92 patients who were alive at one year, 5 (5.4%) had end stage renal disease and were receiving hemodialysis and 3 (3.2%) were dependent on a ventilator. <h3>Conclusion</h3> The 1-year survival free of HT or LVAD in AMI or DHF patients requiring ECMO is low. This is predominantly driven by the outcome on the first 30 days after ECMO implantation. A small proportion of 1-year survivors have end stage renal disease or are dependent on mechanical ventilation.