Inclusion Criteria:  Trusted person or relative who has given oral consent or emergency consent Person of legal age Patient receiving ECLS for refractory cardiogenic shock requiring continuous renal replacement therapy Included within 12 hours of ECLS initiation  Exclusion Criteria:  Person not affiliated to national health insurance Person under legal protection (curatorship, guardianship) Person under court order Pregnant or breastfeeding woman Minor Severe hemorrhage under ECLS