# The relationships between disseminated intravascular coagulation and time series change of Von Willebrand factor in patients with out-of-hospital cardiac arrest: a retrospective observational study

## TL;DR

This study examines how Von Willebrand factor and ADAMTS13 activity change over time in patients with cardiac arrest and disseminated intravascular coagulation.

## Contribution

The study reveals the temporal dynamics of VWF and ADAMTS13 in OHCA patients with DIC, showing no direct causal link between these factors and DIC severity.

## Key findings

- VWF Ag and VWF RCo were elevated in both DIC and non-DIC groups immediately after cardiac arrest.
- DIC severity was associated with lower ADAMTS13 activity and VWF LMI, but not with increased VWF multimer size.
- No correlation was found between VWF activity and DIC severity, suggesting no causal role for VWF in DIC pathogenesis.

## Abstract

Out-of-hospital cardiac arrest (OHCA) is frequently complicated by disseminated intravascular coagulation (DIC), which worsens outcomes. Von Willebrand factor (VWF) is central to haemostasis, and its multimeric size and activity are regulated by ADAMTS13. Decreased ADAMTS13 activity leads to accumulation of ultralarge VWF multimers and microvascular thrombosis. After OHCA, elevated VWF antigen (VWF Ag) and reduced ADAMTS13 activity have been observed and correlate with poor outcomes. However, the relationships among VWF activity, multimer size, and ADAMTS13 activity in DIC after OHCA remain unclear.

This single-centre retrospective study included adult patients with witnessed cardiogenic OHCA admitted to the Hokkaido University Hospital between September 2019 and January 2023. Patients receiving extracorporeal membrane oxygenation were excluded. Plasma samples collected from Day 0 (upon arrival at the emergency department) to Day 4 were analysed for VWF Ag, VWF ristocetin cofactor activity (VWF RCo), VWF large multimer index (VWF LMI), and ADAMTS13 activity. Patients were classified into the DIC and the non-DIC groups. Temporal changes in these biomarkers were compared between the two groups, and their associations with DIC scores were assessed.

Among 28 included patients, 16 fulfilled the DIC criteria upon admission. VWF-Ag and VWF-RCo were markedly elevated in both groups on arrival and continued to rise during the observational period, without significant group differences. The VWF RCo/vWF Ag ratio was decreased in the DIC group. VWF LMI tended to be lower, and ADAMTS13 activity remained consistently reduced in the DIC group compared with the non-DIC group. Increasing DIC scores were associated with higher VWF Ag and lower VWF LMI and ADAMTS13 activity.

In patients with OHCA, VWF Ag and functional activity were markedly elevated from the normal range immediately after cardiac arrest. Furthermore, as the severity of DIC increased, ADAMTS13 activity decreased. However, although VWF Ag increased with increasing DIC severity, the multimeric size did not increase but rather decreased. No correlation was observed between VWF activity and DIC severity. These findings do not confirm a causal role of ADAMTS13 and VWF in the pathogenesis of DIC after OHCA.