(AVK) Anti Vitamin K Treatment In patients with Fontan Surgery

Thrombotic events have been reported as a major cause of morbidity after the Fontan procedure. There is no consensus about the type and duration of postoperative anticoagulation prophylaxis, due to the high risk of bleeding complications, the difficulties in monitoring and the questionable therapeutic compliance in children. In spite of the lack of long term prospective studies in this situation, the ACCP has recommended in their guidelines OAT following Fontan or Glenn operation for at least 6 months. This has also been our practice in our institution during the period of study.

To analyze the efficacy and complications of OAT in our pediatric patients after undergoing the Fontan operation.

Retrospective chart review of all the children treated with OAT in our institution between 1995 and 2009. All patients were treated initially with acenocumarol 0,2 mg/kg, except the Fontan patients, who received 0,1 mg/kg. Target INR was 2–3 for all patients.

The Mann-Whitney test was used to compare the rate of complications, and the percentage of visits out of target INR between the Fontan patients and the rest of the cohort.

There were 61 children (26 female/35 males) aged between 1 month and 17 years, who received OAT with a range of follow up between 4 months and 14 years: 27 after Fontan operation (Group A), an 34 for other reasons (Group B: n=13 non prothetic valve cardiopathy, n=21 treatment of thromboembolic disease).

The average follow-up was similar in both groups (median of 6.5 months in group A vs.7.5 months in group B). There were few complications: 1 mild epistaxis and 1 thrombotic event in group B, and none in group A. There were no differences in the proportion of controls in normal range between both groups; there was a moderate proportion of controls outside the target range of INR, with higher distribution below the range than above the range. The median dose used to achieve the target INR was 0.3 mg/kg/d in Group A and 0.4 mg/kg/d in Group B.

Oral Anticoagulant therapy is safe and effective in pediatric patients,with very low rates of thrombotic or hemorragic complications including those undergoing the Fontan surgery. There were not any differences between both groups in any of the analizyed parameters.

No relevant conflicts of interest to declare.