Purified antithrombin supplementation in coronary revascularisation operations

Background and objective: Purified antithrombin concentrates or human recombinant antithrombin have been proposed for treating heparin resistance in cardiac operations with cardiopulmonary bypass, and exert a beneficial effect in terms of haemostatic system activation control. However, little information is available with respect to antithrombin supplementation and clinical outcome in selected categories of patients. The aim of this study is to evaluate clinical outcome data in patients intraoperatively treated with purified antithrombin compared to a control population. Methods: 89 patients forming the AT-treated group received purified antithrombin to correct preoperatively low values of antithrombin activity or to treat heparin resistance. The Control group was retrospectively created with a propensity score analysis. After verifying the homogeneity of the two groups, various outcome variables were compared between groups. Results: Patients in the AT-treated group had a shorter Intensive Care Unit (2.6 ± 3 vs. 3 ± 2.7 days) and Hospital (7.5 ± 3.5 vs. 8.6 ± 4.5 days) stay, and a lower rate (relative risk 0.1, 95% confidence interval 0.01-0.81) of severe postoperative morbid events. Conversely, they demonstrated a significant, albeit clinically irrelevant, more pronounced postoperative bleeding tendency. Conclusions: AT supplementation in patients at risk for inadequate thrombin suppression during the operation reduces postoperative complications and shortens the recovery time. However, a careful monitoring of the heparin requirements is recommended in order to avoid an undesired excessive postoperative bleeding.