The purpose of this study is to assess coagulation and platelet function in children with congenital heart disease, measured with a bedside device (thromboelastometry and impedance aggregometry).

The investigators also aim to determine if this device detect post-cardiopulmonary bypass clotting derangements and may help to manage bleeding in this population.

Hemostasis, a main concern during and after any surgical procedure, is traditionally monitored by the following laboratory tests: activated Partial Thrombin Time (aPTT), prothrombin time (PT), fibrinogen, platelets count. They neither provide a reliable estimate of the risk of bleeding, nor allow determining useful interventions.

New investigations of hemostasis are now used and validated during and after surgery: Rotational Thromboelastometry (ROTEM®) and impedance aggregometry. This is a quick bedside functional analysis of the patient's clotting. Children who undergo surgery under cardiopulmonary bypass (CPB) are particularly at risk of bleeding and this population hasn't been studied with large cohort yet.

Hypothesis: Hemostasis in children with CHD, especially when cyanotic, is intrinsically abnormal. The corrective surgery on CPB induces further hemostatic disorders which can be identified by the ROTEM platelet®.

The aim of the study is to evaluate the hemostatic function of the child with congenital heart disease using a Point-Of-Care (platelet-ROTEM ®) system, before surgery and after alterations induced by cardiopulmonary bypass (CPB).

This is a single center, observational, prospective study. Expected duration: 2 years. The investigators plan to include 200 patients with CHD, 100 patients undergoing surgery with CPB and 100 patients with congenital heart disease requiring cardiac catheterization. Recruitment will be conducted by the Division of Paediatric Cardiology.

Inclusion criteria include an age of 0-16 years and a diagnosis of congenital heart disease requiring surgery with CPB or cardiac catheterization. Patients with known dyscrasia or treated with antiaggregant within 10 days/oral anticoagulants within 48h before surgery/catheterization.

ROTEM platelet® test will be performed before surgery/catheterization. Patients undergoing surgery will have a second test within 30 minutes after the end of cardiopulmonary bypass. All patients will benefit from the usual cares.

Inclusion Criteria:

• children between 0 and 16 years, born with a congenital heart disease requiring either cardiac catheterization or surgery with cardiopulmonary bypass
• parental and/or patient consent

Exclusion Criteria:

• known hemostatic disorder
• known platelet function disorder
• antiaggregation treatment <10 days before blood sampling
• oral anticoagulation <2 days before blood sampling
• intravenous heparin <6 hours before blood sampling
• patient and parents unable to consent

Children with congenital heart defect