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.