Inclusion Criteria:

Adult patients with septic shock:

• Proven or suspected infection.
• Persistent arterial hypotension requiring norepinephrine administration to maintain a mean arterial pressure above 65 mmHg despite adequate fluid resuscitation.
• Hyperlactatemia > 2 mmol/L.

Adult critically ill control patients with sepsis without circulatory failure:

• Proven or suspected infection.
• Absence of persistent arterial hypotension requiring norepinephrine administration to maintain a mean arterial pressure above 65 mmHg.
• An increase of at least 2 points in the SOFA score attributable to infection.

Adult critically ill control patients with cardiogenic shock:

• Acute cardiac disease, such as myocardial infarction.
• Persistent arterial hypotension requiring norepinephrine administration to maintain a mean arterial pressure above 65 mmHg despite adequate fluid resuscitation.
• Low cardiac output: cardiac index < 2.2 L/min/m² or the need for inotropic support (including norepinephrine) to maintain a cardiac index > 2.2 L/min/m².
• Elevated left ventricular filling pressures, measured invasively or estimated by echocardiography.
• Hyperlactatemia > 2 mmol/L.

Adult healthy volunteers:

• Absence of active or chronic disease.
• Absence of long-term medication use.
• No surgery or medication intake within the previous month.
• Absence of ongoing pregnancy.
• Non-smoker.

Exclusion Criteria:

• Patients deprived of liberty by judicial or administrative decision.
• Patients admitted to the intensive care unit for more than 48 hours.
• Patients previously enrolled in an interventional study with overlapping follow-up.
• Patients benefiting from State Medical Aid (AME).