Background and Purpose— After large-vessel intracranial occlusion, the fate of the ischemic penumbra, and ultimately final infarct volume, largely depends on tissue perfusion. In this study, we evaluated whether blood pressure reduction and sustained relative hypotension during endovascular thrombectomy are associated with infarct progression and functional outcome. Methods— We identified consecutive patients with large-vessel intracranial occlusion ischemic stroke who underwent mechanical thrombectomy at 2 comprehensive stroke centers. Intraprocedural mean arterial pressure (MAP) was monitored throughout the procedure. ΔMAP was calculated as the difference between admission MAP and lowest MAP during endovascular thrombectomy until recanalization. Sustained hypotension was measured as the area between admission MAP and continuous measurements of intraprocedural MAP (aMAP). Final infarct volume was measured using magnetic resonance imaging at 24 hours, and functional outcome was assessed using the modified Rankin Scale at discharge and 90 days. Associations with outcome were analyzed using linear and ordinal multivariable logistic regression. Results— Three hundred ninety patients (mean age 71±14 years, mean National Institutes of Health Stroke Scale score of 17) were included in the study; of these, 280 (72%) achieved Thrombolysis in Cerebral Infarction 2B/3 reperfusion. Eighty-seven percent of patients experienced MAP reductions during endovascular thrombectomy (mean 31±20 mm Hg). ΔMAP was associated with greater infarct growth ( P =0.036) and final infarct volume ( P =0.035). Mean ΔMAP among patients with favorable outcomes (modified Rankin Scale score, 0–2) was 20±21 mm Hg compared with 30±24 mm Hg among patients with poor outcome ( P =0.002). In the multivariable analysis, ΔMAP was independently associated with higher (worse) modified Rankin Scale scores at discharge (adjusted odds ratio per 10 mm Hg, 1.17; 95% CI, 1.04–1.32; P =0.009) and at 90 days (adjusted odds ratio per 10 mm Hg, 1.22; 95% CI, 1.07–1.38; P =0.003). The association between aMAP and outcome was also significant at discharge ( P =0.002) and 90 days ( P =0.001). Conclusions— Blood pressure reduction before recanalization is associated with larger infarct volumes and worse functional outcomes for patients affected by large-vessel intracranial occlusion stroke. These results underscore the importance of BP management during endovascular thrombectomy and highlight the need for further investigation of blood pressure management after large-vessel intracranial occlusion stroke.

Background and Purpose— Loss of cerebral autoregulation in the acute phase of ischemic stroke leaves patients vulnerable to blood pressure (BP) changes. Effective BP management after endovascular thrombectomy may protect the brain from hypoperfusion or hyperperfusion. In this observational study, we compared personalized, autoregulation-based BP targets to static systolic BP thresholds. Methods— We prospectively enrolled 90 patients undergoing endovascular thrombectomy for stroke. Autoregulatory function was continuously measured by interrogating changes in near-infrared spectroscopy–derived tissue oxygenation (a cerebral blood flow surrogate) in response to changes in mean arterial pressure. The resulting autoregulatory index was used to trend the BP range at which autoregulation was most preserved. Percent time that mean arterial pressure exceeded the upper limit of autoregulation or decreased below the lower limit of autoregulation was calculated for each patient. Time above fixed systolic BP thresholds was computed in a similar fashion. Functional outcome was measured with the modified Rankin Scale at 90 days. Results— Personalized limits of autoregulation were successfully computed in all 90 patients (age 71.6±16.2, 47% female, mean National Institutes of Health Stroke Scale 13.9±5.7, monitoring time 28.0±18.4 hours). Percent time with mean arterial pressure above the upper limit of autoregulation associated with worse 90-day outcomes (odds ratio per 10% 1.84 [95% CI, 1.3–2.7] P =0.002), and patients with hemorrhagic transformation spent more time above the upper limit of autoregulation (10.9% versus 16.0%, P =0.042). Although there appeared to be a nonsignificant trend towards worse outcome with increasing time above systolic BP thresholds of 140 mm Hg and 160 mm Hg, the effect sizes were smaller compared with the personalized approach. Conclusions— Noninvasive determination of personalized BP thresholds for stroke patients is feasible. Deviation from these limits may increase risk of further brain injury and poor functional outcome. This approach may present a better strategy compared with the classical approach of maintaining systolic BP below a predetermined value, though a randomized trial is needed to determine the optimal approach for hemodynamic management.

Background and Purpose— Optimal blood pressure (BP) management during the early stages of aneurysmal subarachnoid hemorrhage remains uncertain. Observational studies have found worse outcomes in patients with increased hemodynamic variability, suggesting BP optimization as a potential neuroprotective strategy. In this study, we calculated personalized BP targets at which cerebral autoregulation was best preserved. We analyzed how deviation from these limits correlates with functional outcome. Methods— We prospectively enrolled 31 patients with aneurysmal subarachnoid hemorrhage. Autoregulatory function was continuously measured by interrogating changes in near-infrared spectroscopy (NIRS)-derived tissue oxygenation—a surrogate for cerebral blood flow—as well as intracranial pressure (ICP) in response to changes in mean arterial pressure using time-correlation analysis. The resulting autoregulatory indices were used to identify the upper and lower limit of autoregulation. Percent time that mean arterial pressure exceeded limits of autoregulation was calculated for each patient. Functional outcome was assessed using the modified Rankin Scale at discharge and 90 days. Associations with outcome were analyzed using ordinal multivariate logistic regression. Results— Personalized limits of autoregulation were computed in all patients (age 57.5±13.4, 23F, mean World Federation of Neurological Surgeons 2±1, monitoring time 67.8±50.8 hours). Optimal BP and limits of autoregulation were calculated on average for 89.5±6.7% of the total monitoring period. ICP- and NIRS-derived optimal pressures strongly correlated with one another ( P <0.0001). Percent time that mean arterial pressure deviated from limits of autoregulation significantly associated with worse functional outcome at discharge (NIRS, P =0.001; ICP, P =0.004) and 90 days (NIRS, P =0.002; ICP, P =0.003), adjusting separately for age, World Federation of Neurological Surgeons, vasospasm, and delayed cerebral ischemia. Conclusions— Both invasive (ICP) and noninvasive (NIRS) determination of personalized BP targets after aneurysmal subarachnoid hemorrhage is feasible, and these 2 approaches revealed significant collinearity. Furthermore, exceeding individualized limits of autoregulation was associated with poor functional outcomes.

Background and Purpose: Elevated blood pressure after endovascular thrombectomy (EVT) has been associated with an increased risk of hemorrhagic transformation and poor functional outcomes. However, the optimal hemodynamic management after EVT remains unknown, and the blood pressure course in the acute phase of ischemic stroke has not been well characterized. This study aimed to identify patient subgroups with distinct blood pressure trajectories after EVT and study their association with radiographic and functional outcomes. Methods: This multicenter retrospective cohort study included consecutive patients with anterior circulation large-vessel occlusion ischemic stroke who underwent EVT. Repeated time-stamped blood pressure data were recorded for the first 72 hours after thrombectomy. Latent variable mixture modeling was used to separate subjects into five groups with distinct postprocedural systolic blood pressure (SBP) trajectories. The primary outcome was functional status, measured on the modified Rankin Scale 90 days after stroke. Secondary outcomes included hemorrhagic transformation, symptomatic intracranial hemorrhage, and death. Results: Two thousand two hundred sixty-eight patients (mean age [±SD] 69±15, mean National Institutes of Health Stroke Scale 15±7) were included in the analysis. Five distinct SBP trajectories were observed: low (18%), moderate (37%), moderate-to-high (20%), high-to-moderate (18%), and high (6%). SBP trajectory group was independently associated with functional outcome at 90 days ( P <0.0001) after adjusting for potential confounders. Patients with high and high-to-moderate SBP trajectories had significantly greater odds of an unfavorable outcome (adjusted odds ratio, 3.5 [95% CI, 1.8–6.7], P =0.0003 and adjusted odds ratio, 2.2 [95% CI, 1.5–3.2], P <0.0001, respectively). Subjects in the high-to-moderate group had an increased risk of symptomatic intracranial hemorrhage (adjusted odds ratio, 1.82 [95% CI, 1–3.2]; P =0.04). No significant association was found between trajectory group and hemorrhagic transformation. Conclusions: Patients with acute ischemic stroke demonstrate distinct SBP trajectories during the first 72 hours after EVT that have differing associations with functional outcome. These findings may help identify potential candidates for future blood pressure modulation trials.

OBJECTIVEWhile the benefit of mechanical thrombectomy (MT) for patients with anterior circulation acute ischemic stroke with large-vessel occlusion (AIS-LVO) has been clearly established, difficult vascular access may make the intervention impossible or unduly prolonged. In this study, the authors evaluated safety as well as radiographic and functional outcomes in stroke patients treated with MT via direct carotid puncture (DCP) for prohibitive vascular access.METHODSThe authors retrospectively studied patients from their prospective AIS-LVO database who underwent attempted MT between 2015 and 2018. Patients with prohibitive vascular access were divided into two groups: 1) aborted MT (abMT) after failed transfemoral access and 2) attempted MT via DCP. Functional outcome was assessed using the modified Rankin Scale at 3 months. Associations with outcome were analyzed using ordinal logistic regression.RESULTSOf 352 consecutive patients with anterior circulation AIS-LVO who underwent attempted MT, 37 patients (10.5%) were deemed to have prohibitive vascular access (mean age [± SD] 82 ± 11 years, mean National Institutes of Health Stroke Scale [NIHSS] score 17 ± 5, with females accounting for 75% of the patients). There were 20 patients in the DCP group and 17 in the abMT group. The two groups were well matched for the known predictors of clinical outcome: age, sex, and admission NIHSS score. Direct carotid access was successfully obtained in 19 of 20 patients. Successful reperfusion (thrombolysis in cerebral infarction score 2b or 3) was achieved in 16 (84%) of 19 patients in the DCP group. Carotid access complications included an inability to catheterize the carotid artery in 1 patient, neck hematomas in 4 patients, non–flow-limiting common carotid artery (CCA) dissections in 2 patients, and a delayed, fatal carotid blowout in 1 patient. The neck hematomas and non–flow-limiting CCA dissections did not require any subsequent interventions and remained clinically silent. Compared with the abMT group, patients in the DCP group had smaller infarct volumes (11 vs 48 ml, p = 0.04), a greater reduction in NIHSS score (−4 vs +2.9, p = 0.03), and better functional outcome (shift analysis for 3-month modified Rankin Scale score: adjusted OR 5.2, 95% CI 1.02–24.5; p = 0.048).CONCLUSIONSDCP for emergency MT in patients with anterior circulation AIS-LVO and prohibitive vascular access is safe and effective and is associated with higher recanalization rates, smaller infarct volumes, and improved functional outcome compared with patients with abMT after failed transfemoral access. DCP should be considered in this patient population.

Background and Purpose: We aim to examine effects of collateral status and post-thrombectomy reperfusion on final infarct distribution and early functional outcome in patients with anterior circulation large vessel occlusion ischemic stroke. Methods: Patients with large vessel occlusion who underwent endovascular intervention were included in this study. All patients had baseline computed tomography angiography and follow-up magnetic resonance imaging. Collateral status was graded according to the criteria proposed by Miteff et al and reperfusion was assessed using the modified Thrombolysis in Cerebral Infarction (mTICI) system. We applied a multivariate voxel-wise general linear model to correlate the distribution of final infarction with collateral status and degree of reperfusion. Early favorable outcome was defined as a discharge modified Rankin Scale score ≤2. Results: Of the 283 patients included, 129 (46%) had good, 97 (34%) had moderate, and 57 (20%) had poor collateral status. Successful reperfusion (mTICI 2b/3) was achieved in 206 (73%) patients. Poor collateral status was associated with infarction of middle cerebral artery border zones, whereas worse reperfusion (mTICI scores 0–2a) was associated with infarction of middle cerebral artery territory deep white matter tracts and the posterior limb of the internal capsule. In multivariate regression models, both mTICI ( P <0.001) and collateral status ( P <0.001) were among independent predictors of final infarct volumes. However, mTICI ( P <0.001), but not collateral status ( P =0.058), predicted favorable outcome at discharge. Conclusions: In this cohort of patients with large vessel occlusion stroke, both the collateral status and endovascular reperfusion were strongly associated with middle cerebral artery territory final infarct volumes. Our findings suggesting that baseline collateral status predominantly affected middle cerebral artery border zones infarction, whereas higher mTICI preserved deep white matter and internal capsule from infarction; may explain why reperfusion success—but not collateral status—was among the independent predictors of favorable outcome at discharge. Infarction of the lentiform nuclei was observed regardless of collateral status or reperfusion success.

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From 2004 to 2015, the average number of neurologists in high-income countries increased from 3 to 5.14 per 100,000 population; the number of neurologists in low-income countries (LICs) remained static at 0.03 per 100,000. 1,2 This disparity is likely due in large part to the paucity of neurology training programs in LICs, 3 leading physicians interested in neurology to train abroad, where many stay (the brain drain phenomenon). 4 Neurologic disorders are the leading cause of disability-adjusted life-years and the second leading cause of mortality worldwide, 5 requiring expansion of the global neurology workforce. Here we describe the development of the first neurology training program in Haiti (an LIC), supported by a visiting faculty model.There is only one neurologist in Haiti (population ;11 million), limiting access to neurologic care for patients and neurology education for providers. Hôpital Universitaire de Mirebalais (HUM) is a 300-bed public academic hospital in Haiti, run through a partnership among the Haitian Ministry of Health, the nongovernmental organization Partners In Health (PIH), and PIH's Haitian sister organization Zanmi Lasante (ZL). HUM has residency programs in internal medicine, pediatrics, obstetrics/gynecology, surgery, and emergency medicine; a primary catchment area of ;185,000; a tertiary catchment area of ;3 million; and daily outpatient volume of ;700 patients. Program establishmentPrior to the development of the neurology training program, we established a neurology rotation for HUM internal medicine residents. e1 The rotation demonstrated sufficient volume and variety of neurologic patients and the efficacy of a visiting faculty model to train local providers. The Director of Graduate Medical Education (GME) at HUM (K.I.), the Deputy Chief Medical Officer for PIH in Haiti (M.E.M.), and the visiting neurologist who ran the rotation (A.L.B.) developed a proposal for a neurology fellowship program.From Partners in Health/Zanmi Lasante (K.