Introduction: Observational studies have found an increased risk of hemorrhagic transformation and worse functional outcomes in patients with higher systolic blood pressure variability (BPV). However, the time-varying behavior of BPV after endovascular thrombectomy (EVT) and its effects on functional outcome have not been well characterized. Patients and methods: We analyzed data from an international cohort of patients with large-vessel occlusion stroke who underwent EVT at 11 centers across North America, Europe, and Asia. Repeated time-stamped blood pressure data were recorded for the first 72 h after thrombectomy. Parameters of BPV were calculated in 12-h epochs using five established methodologies. Systolic BPV trajectories were generated using group-based trajectory modeling, which separates heterogeneous longitudinal data into groups with similar patterns. Results: Of the 2041 patients (age 69 ± 14, 51.4% male, NIHSS 15 ± 7, mean number of BP measurements 50 ± 28) included in our analysis, 1293 (63.4%) had a poor 90-day outcome (mRS ⩾ 3) or a poor discharge outcome (mRS ⩾ 3). We identified three distinct SBP trajectories: low (25%), moderate (64%), and high (11%). Compared to patients with low BPV, those in the highest trajectory group had a significantly greater risk of a poor functional outcome after adjusting for relevant confounders (OR 2.2; 95% CI 1.2–3.9; p = 0.008). In addition, patients with poor outcomes had significantly higher systolic BPV during the epochs that define the first 24 h after EVT ( p < 0.001). Discussion and conclusions: Acute ischemic stroke patients demonstrate three unique systolic BPV trajectories that differ in their association with functional outcome. Further research is needed to rapidly identify individuals with high-risk BPV trajectories and to develop treatment strategies for targeting high BPV.

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Introduction: High blood pressure after endovascular thrombectomy (EVT) can cause cerebral hyperemia and disrupt the blood-brain barrier. However, its role in cerebral edema development is incompletely understood. In this study, we examined the relationship between post-EVT systolic blood pressure (SBP) trajectories and cerebral edema. Methods: We prospectively enrolled patients with large-vessel occlusion stroke who underwent EVT. Cerebrospinal fluid (CSF) volume was measured using a deep-learning algorithm on CT images at baseline, 24 hours, and 72 hours after stroke. The ratio of CSF volumes between hemispheres was calculated. Automated segmentation of infarct regions on follow-up scans was used to measure net water uptake (NWU), the ratio of density within infarcted tissue relative to the mirrored contralateral region. Latent variable mixture modeling (LVMM) divided patients into SBP trajectory groups during the first 72 hours post-EVT (Fig. 1A). Measures of edema (change in CSF ratio, NWU) were compared between groups. Results: One hundred patients (mean age 70 ± 16, mean NIHSS 15) were analyzed. Edema was assessed by a gradual increase in NWU (20.5, 27.0) at 24 and 72 hours, respectively, and by a reduction in CSF ratio (0.95, 0.78, 0.68) in the affected hemisphere at baseline, 24 hours, and 72 hours, respectively. LVMM identified five SBP trajectories. Higher SBP trajectories were associated with higher NWU (Fig. 1B) but not lower CSF ratio at 24 hours (p<0.001 and p=0.343, respectively). After adjusting for age, admission NIHSS, and TICI score, the moderate-to-high and high-to-moderate trajectory groups were independently associated with higher NWU (aOR 11.40, 95% CI 2.14-20.66) and (aOR 10.97, 95% CI 0.12-21.82), relative to the low and moderate groups. Conclusions: Higher SBP trajectories are associated with an increase in NWU post-EVT. NWU is a promising radiographic biomarker for measuring cerebral edema during the early phase after stroke.

Background: Cerebral near-infrared spectroscopy (NIRS) is a useful tool to monitor real-time cerebral oxygenation levels. However, the mechanisms through which varying oxygenation levels during endovascular thrombectomy (EVT) affect functional outcomes remain to be determined. In this study, we categorized NIRS trends into descriptive “fingerprints” and examined the relationship between these fingerprints and neurological worsening. Methods: We enrolled patients that presented to Yale New Haven Hospital with large vessel occlusion acute ischemic stroke and underwent EVT. NIRS was implemented into the standard operating procedure. Time stamps of defined events (medication administration, recanalization, etc.) were synchronized with corresponding NIRS values. We inspected NIRS curves from arrival to angio-suite to time of recanalization. Neurological deterioration was defined as an increase of 4 points or more on the National Institutes of Health Stroke Scale (NIHSS). Results: Forty-eight patients (mean age 72 ± 13, mean NIHSS 14) were analyzed. Five “fingerprints” were observed in the affected hemisphere: sustained decreases, downward rSO2 peaks, no change, upward rSO2 peaks, and sustained increases (Fig. 1), which were assigned nominal values of -2, -1, 0, 1, and 2, respectively. After adjusting for age and admission NIHSS, sustained decreases and downward rSO2 peaks were independently associated with neurological deterioration (P = 0.0076, Fig. 2). Conclusions: Identifiable NIRS “fingerprints” of downward rSO2 peaks and sustained decreases in the affected hemisphere during EVT are associated with neurological deterioration. Further distillation of identifiable intraprocedural NIRS trends in real time could provide guidance for anesthesia and hemodynamic management during EVT to optimize patient outcomes after stroke.

Introduction: High blood pressure variability (BPV) after endovascular thrombectomy is associated with post-stroke complications and poor neurological outcomes. However, whether BPV is an epiphenomenon of the stroke itself or causally related to the outcome remains unknown. Objective: In this study we aimed to evaluate if a relationship exists between pre-and post-stroke BPV in patients with large vessel occlusions (LVO). Methods: From our prospective stroke registry, we identified patients who had an anterior circulation LVO, underwent EVT, and had at least three blood pressure measurements recorded in the electronic medical record in the six months prior to their stroke admission. All patients had repeated time-stamped blood pressure data recorded for the first 72 hours after thrombectomy. Using the standard deviation of systolic BP, we calculated BPV for each patient and separated patients into tertiles based on their post-EVT BPV. The relationship between pre-stroke BPV and post-EVT BPV was analyzed using an ordinal logistic regression and Spearman’s rank correlation analysis. Results: Two hundred fifty-two patients were included in our analysis (mean age 70±16.2 years, mean admission NIHSS 15±7, median pre-stroke BP measurements 14.5 (IQR 5.0-55.8)). Pre-stroke BPV gradually increased for patients with higher post-EVT BPV tertiles (tertile 1 = 13.2(±5.2) mmHg, tertile 2 = 15.0(±5.5) mmHg, tertile 3 = 16.7(±7.0) mmHg, p=0.001). A positive correlation was observed between pre-stroke BPV and post-EVT BPV (p<0.001, R=0.21). After adjusting for age and admission NIHSS, pre-stroke BPV was significantly associated with post-EVT BPV tertile membership (OR 1.37, 95% CI 1.02-1.86, p=0.039). Conclusion: High pre-stroke BPV is correlated with high post-EVT BPV. Although larger, prospective studies are needed to provide definitive evidence of this relationship, our work suggests that high post-EVT BPV may be related to an underlying biological phenomenon and not merely a consequence of the stroke itself. Individuals with high BPV may benefit from more intensive blood pressure management in the acute phase after EVT.