Estimation of the Prevalence of Microcirculatory Dysfunction in Uremic Cardiopathy Among Dialysis Patients

Inclusion Criteria: * Age ≥ 18 years * Patients who have been on haemodialysis for at least 6 months * Elevated troponin levels \> 40 ng/L in a sample taken whilst the patient was in a stable condition, dated within the last 3 months * Patients capable of understanding the protocol and who have given their written informed consent to participate in the research * Patients registered with the National Health Service or eligible for it Exclusion Criteria: * Age \> 90 years * Patient undergoing daily home haemodialysis * Symptomatic stage 3 or 4 peripheral arterial disease * Severe hypertrophic cardiomyopathy (genetic or amyloid) * Severe valvular heart disease leading to left ventricular remodelling (surgically contraindicated severe aortic stenosis, severe mitral regurgitation, severe aortic regurgitation) * Hospitalisation for decompensation/acute heart failure within the last month * Acute coronary syndrome and any coronary artery disease requiring angioplasty and/or stent implantation within the last 3 months * Contraindication to METHERGIN and DOBUTAMINE * Patients participating in another clinical research protocol that may affect the research objectives * Patients already included in the study * Patients under guardianship, curatorship or deprived of their liberty * Patients under an activated future protection order * Patients under family authorisation * Patient under judicial protection * Pregnant patient