Abstract WP374: High Frequency Blood Pressure Monitoring in the Acute Phase of Large Vessel Occlusion Ischemic Stroke

Abstract

Introduction: Decreases in blood pressure (BP) during endovascular therapy (EVT) have been associated with infarct progression and worse outcome after large vessel occlusion (LVO) stroke. However, BP trajectories in the acute phase prior to EVT have not been well characterized. We thus used high-frequency BP and hemodynamic monitoring to create a continuous BP time trend and to determine timing of BP reductions. Methods: We prospectively enrolled patients with LVO stroke undergoing EVT. BP and cardiac hemodynamic variables were recorded every 20 seconds from emergency room admission until end of EVT using non-invasive finger plethysmography. Time trends of BP recordings were categorized into 4 windows: admission to imaging; imaging to EVT; EVT to groin puncture and groin puncture to recanalization. Episodes of hypotension (mean arterial pressure ≤ 70 mmHg) were correlated with administered medications and other potentially related interventions. Time trends in hemodynamic variables were analyzed using generalized estimating equations. Results: 25 patients underwent continuous BP monitoring (age 74±18; 68% female; mean NIHSS 12, monitoring time 8.34±2 hrs). Aggregated time series data revealed a marked BP reduction around time of imaging from which patients recovered (mean SBP 33 mmHg, duration 18 min, Fig A). A sustained decrease in BP was observed after groin puncture without return to baseline BP levels. In 62% of cases, reductions in BP were associated with BP lowering medications. A significant reduction in cardiac output (p=0.003) and increase in stroke volume variation (p=0.022) was seen across predetermined time points (Fig B & C). Conclusion: In patients with LVO, marked and frequently iatrogenic BP reductions occur around time of initial imaging and may present a potential target for intervention. Changes in cardiac hemodynamic variables throughout acute stroke period suggest a potential role for fluid resuscitation for hemodynamic optimization.