Altered levels of coagulation factors are reported in patients with functionally univentricular physiology before and following the second and third stages of reconstructive surgery. The aims of our study were to determine if such abnormalities are also present in newborns with this physiology prior to the first stage of surgical treatment.

We studied 20 neonates with functionally univentricular physiology admitted to the Children’s Cardiac Centre in Slovakia, using 20 healthy neonates as age-matched controls. Demographic characteristics, and concentration of liver enzymes, serum albumin, and complete blood count, did not differ between the two groups. Concentrations of Factor II, V, VII, VIII, Protein C, Protein S and Antithrombin were compared between the groups, and assessed as variable factors for coagulation.

In those with functionally univentricular physiology, procoagulation Factor II (p < 0.001), VII (p < 0.001), VIII (p < 0.01), anticoagulation Protein C (p < 0.001), Protein S (p < 0.001) and Antitrombin III (p < 0.001) all were present in significantly lower values compared with findings in the control group. D-dimer (p < 0.0001) and Fibrin Degradation Products (p < 0.0001) were present at significantly higher levels, but the concentration of plasminogen was significantly lower (p < 0.0001). The activated partial thromboplastin time (p < 0.012), and the prothrombin time (p < 0.0001), was significantly prolonged in those with functionally univentricular physiology compared with their controls.

The presence of abnormal coagulation factors, markers of thrombolysis in the plasma, and increased risk of bleeding, suggests activation of haemostasis, and consumption of factors responsible for coagulation, in those with functionally univentricular physiology. The question arises whether the reported abnormalities are predictive of the known abnormalities of coagulation occurring during the second and third stages of surgical repair for patients with functionally univentricular hearts.