Prolonged Venous Transit Is Associated With Unfavorable Outcomes in Anterior Circulation Distal Medium Vessel Stroke

Background and Purpose Distal medium‐vessel occlusion (DMVO) strokes represent a significant proportion of acute ischemic stroke cases, yet optimal management remains unclear. Prolonged venous transit (PVT), a marker of poor venous outflow, has been associated with worse outcomes in large‐vessel occlusion strokes, but its role in DMVO is unknown. Methods In a retrospective study, consecutive patients with anterior‐circulation DMVO, defined as occlusions in the M2–M4 segments of the middle cerebral artery or the anterior cerebral artery. PVT status was determined on pretreatment time‐to‐maximum perfusion maps by identifying ≥10‐s delays in either the posterior superior sagittal sinus or the torcula. Baseline characteristics, imaging findings, and interventions were collected. The primary outcome was a 90‐day modified Rankin Scale (mRS) score of 0–2. Results Among 77 patients (median age 70 years, 56% female), 18 (23%) had PVT. Median admission National Institutes of Health Stroke Scale scores were 11 (interquartile range, 7–15), and intravenous thrombolysis was administered to 35% of patients. Patients with PVT+ were less likely to achieve mRS 0–2 at 90 days (adjusted odds ratio, 0.14; 95% confidence interval, 0.02–0.85; p = 0.046). There were no significant differences in rates of hemorrhagic transformation or mortality. Conclusions PVT is independently associated with unfavorable functional outcomes in anterior‐circulation DMVO. These findings suggest PVT may serve as a prognostic indicator and could inform treatment decisions in this challenging stroke subtype.