According to literature data, Endocan can detect the onset of respiratory failure. The investigators aim to prove its value also for cardiac surgery patients.

Endocan is an endothelium derived soluble dermatan sulfate proteoglycan. Literature data shows that alterate levels of its blood concentration correlate with the onset of pulmonary failure in patients with major trauma and septic shock.

In cardiac surgery respiratory failure and infections are threatening complications leading to mortality rates up to 80%. A rapid diagnosis and treatment of this pathology is crucial to improve the clinical outcome.

Unfortunately specific data for the efficacy of Endocan predictive value in cardiac surgery patients are not available.

The investigators aim to determinate if Endocan can be a helpful tool to identify patients developing acute respiratory failure after cardiac surgery and anticipate specific treatment in order to improve survival.

Inclusion Criteria:

• Able to give written consent
• Elective cardiac surgery
• More than 18 years old

Exclusion Criteria:

• Less than 18 years old
• urgency / emergency cardiac surgery
• pregnancy
• refusal
• unable to give written consent
• oncologic patients
• concomitant inflammatory or infective pulmonary disease