Abstract WP084: The Effect of Time to Therapeutic Anticoagulation in Cerebral Venous Sinus Thrombosis: Evidence, Gaps, and Clinical Implications

Background: Anticoagulation is the standard of care for acute CVST. Guidelines favor LMWH over UFH due to better functional outcomes and lower mortality and complication rates. However, the time to achieve therapeutic anticoagulation (TTA) is under-studied and may be a modifiable systems metric. Objectives: To review evidence on TTA in acute CVST comparing LMWH and UFH, contrast UFH operational reliability vs LMWH predictability, and outline clinical and research implications; especially whether faster TTA is associated with improved resource use and outcomes. Methods: We conducted a narrative literature review of PubMed, Google Scholar, and ScienceDirect through September 2025 using the keywords “cerebral venous sinus thrombosis,” “anticoagulation,” “unfractionated heparin,” “low-molecular-weight heparin,” “direct oral anticoagulants,” and “time to therapeutic anticoagulation.” Two authors independently screened and reviewed eligible articles. Snowballing was performed by examining references of included studies and relevant guidelines (AHA/ASA 2011, 2024; ESO 2017; ACOG 2018). Results: In a critical care CVST cohort, Zichichi et al. reported a median 7.5 h from diagnosis to anticoagulation start and 27.2 h to reach therapeutic UFH, with conservative dosing delaying treatment but not increasing ICH. Torppey et al. confirmed that UFH TTA is operationally unreliable, with only ~29% of aPTT values therapeutic at 24 h and ~40% at 25–48 h despite protocolized infusions. Even with electronic alert systems, mean time to minimal therapeutic aPTT improved only from 21.8 h to 15.4 h, and attainment by 24 h rose from 65.7% to 82.4%. In contrast, LMWH achieves peak anti-Xa activity within 3–5 h with predictable absorption; observational data and one RCT suggest it may reduce in-hospital mortality and ICH relative to UFH, supporting LMWH as default when rapid reversibility is not essential. Importantly, more rapid anticoagulation has been associated with shorter ICU stay without safety trade-off, underscoring TTA as a modifiable systems metric. DOACs remain limited to the post-acute phase; even the SECRET rivaroxaban feasibility trial required heparin lead-in, aligning with 2024 AHA/ASA guidance. Conclusion: TTA is a measurable, modifiable quality metric in CVST. LMWH offers more reliable attainment than UFH, while UFH remains valuable when rapid reversal is required. Prospective studies should test whether faster TTA improves outcomes.