Acquired von Willebrand's Syndrome in Congenital Heart Disease

Background: The aVWS (acquired von Willebrand's syndrome) has been reported in association with congenital heart diseases (CHD) causing high shear. Its incidence and impact on intraoperative bleeding have not been systematically evaluated by now. This was also due to the lack of methods for rapid testing under intraoperative conditions.

Method: This prospective observational single-center pilot trial searched for appropriate diagnostic tools and predictors of aVWS in neonates and infants with CHD undergoing cardiac surgery. The study aimed to clarify to which extent aVWS contributes to intraoperative hemorrhage.

Results: A total of 65 infants, categorized into four groups according to the type of surgery, could be included in the study. Intraoperative high molecular weight multimers (HMWM) ratio was inversely correlated with duration of cardiopulmonary bypass (r = −0.55) and aortic cross clamp time (r = −0.49) but showed weaker correlations with surrogate bleeding parameters such as quantity of supplemented platelets (r = −0.28), fibrinogen (r = −0.34), and fresh frozen plasma (r = −0.35). The GP1bM/VWF:Ag ratio provided meaningful predictability of aVWS (AUC = 0.81) with good correlation to HMWM ratio (r = 0.64). The aVWS positive patients in the neonatal group had longer chest closure times compared with aVWS negative patients (146 [118–174] vs. 95 [74–115] min, p = 0,016).

Conclusion: CPB triggers aVWS in pediatric cardiac surgery. The aVWS is not a major cause of bleeding after cardiac surgery, but its correction might be beneficial in selected cases. The GP1bM/VWF:Ag ratio is feasible for rapid aVWS diagnostics and should be implemented in the routine hemostatic workup of complex CHD surgery. A cut-off value of 0.85 is proposed as a basis for further prospective randomized trials evaluating the effect of von Willebrand's factor supplementation on intraoperative bleeding.

Publication History

Article published online:
12 February 2022