Effectiveness and safety of endovascular thrombectomy for large versus medium vessel occlusions: a single-center experience.

BACKGROUND: The effectiveness and safety of endovascular thrombectomy (EVT) for medium vessel occlusions (MeVO) in the anterior intracranial circulation for patients with acute ischemic stroke (AIS) has yet to be definitively established. We compared outcomes in patients undergoing EVT for large vessel occlusion (LVO) versus those with MeVO. METHODS: This retrospective cohort study, using an intention to treat design, compared the 90-day modified Rankin Scale (mRS) score between 43 patients with MeVO and 199 with LVO in the anterior intracranial circulation. Secondary outcome measures included vessel recanalization using the Thrombolysis in Cerebral Infarction (TICI) score, procedural complications, post-EVT intracranial hemorrhage (ICH), and infarct size. RESULTS: The rate of good functional outcome (90-day mRS 0-2) was higher in patients with LVO than in those with MeVO (32.9% vs 27%), but this was not statistically significant (p=0.19). The rate of EVT procedural complications was also not significantly different between the groups (p=0.10), nor was the rate of ICH (p=0.30). There was also no significant difference in TICI scores between groups (p=0.12). Infarct size was larger in the LVO group (p<0.01). Multivariate analysis showed older age, not receiving recombinant tissue plasminogen activator (r-tPA), and larger infarct size were independent predictors of poor functional outcome at 90 days. CONCLUSION: The 90-day mRS and rate of periprocedural complications were not significantly different between patients treated for LVO and those treated for MeVO with EVT. Older age, not receiving r-tPA, and larger infarct size were independent predictors of poor outcome at 90 days.

Access to Endovascular Thrombectomy for Stroke in Rural Versus Urban Regions.

PURPOSE: Endovascular thrombectomy (EVT) significantly improves outcomes for acute ischemic stroke patients with large vessel occlusion (LVO) who present in a time sensitive manner. Prolonged EVT access times may reduce benefits for eligible patients. We evaluated the efficiency of EVT services including EVT rates, onset-to-CTA time and onset-to-groin puncture time in our province. MATERIALS AND METHODS: Three areas were defined: zone I- urban region, zone II-areas within 1 h drive distance from the Comprehensive Stroke Center (CSC); and zone III-areas more than 1hr drive distance from the CSC. In this retrospective cohort study, EVT rate, onset-to-groin puncture time and onset-to-CTA time were compared among the three groups using Krustal-Wallis and Wilcoxon tests. RESULTS: The EVT rate per 100,000 inhabitants for urban zone I was 8.6 as compared to 5.1 in zone II, and 7.5 in zone III. Compared to zone I (114 min; 95% CI (96, 132); n = 128), mean onset-to-CTA time was 19 min longer in zone II (133 min; 95% CI (77, 189); n = 23; p = 0.0459) and 103 min longer in zone III (217 min, 95% CI (162, 272); n = 44; p < 0.0001). Compared to zone I (209 min, 95% CI (181, 238)), mean onset-to-groin puncture time was 22 min longer in zone II (231 min, 95% CI (174, 288); p = 0.046) but 163 min longer in zone III (372 min, 95% CI (312, 432); p < 0.0001). CONCLUSION: EVT access in rural areas is considerably reduced with significantly longer onset-to-groin puncture times and onset-to-CTA times when compared to our urban area. This may help in modifying the patient transfer policy for EVT referral.

Suboptimal Outcome with Endovascular Thrombectomy: Will Acute Stroke Unit Help?

Endovascular thrombectomy (EVT) has revolutionized the care of patients with acute ischemic stroke. The efficacy of EVT is dependent on the optimal setup of a stroke system. Extrapolating the results of clinical trials to any individual stroke center should be done with caution. This is more important for centers with suboptimal stroke systems of care. The Canadian registry has helped highlight the suboptimal outcome post EVT in Manitoba. This could potentially be optimized with the addition of an acute stroke unit in the near future. Our study will serve as a baseline for future improvement in acute stroke care.

Prehospital Management of Acute Stroke in Rural versus Urban Responders.

OBJECTIVE: Stroke guideline compliance of rural Canadian prehospital emergency medical services (EMS) care in acute stroke is unknown. In this quality assurance study, we sought to compare rural and urban care by prehospital EMS evaluation/management indicators from patients assessed at an urban Canadian stroke center. MATERIALS AND METHODS: One hundred adult patients were randomly selected from the stroke registry. Patients were transported through Rural EMS bypass protocols or urban EMS protocols (both bypass and direct) to our stroke center between January and December 2013. Patients were excluded if they were first evaluated at any other health center. Prehospital care was assessed using ten indicators for EMS evaluation/management, as recommended by acute stroke guidelines. RESULTS: Compliance with acute stroke EMS evaluation/management indicators were statistically similar for both groups, except administrating a prehospital diagnostic tool (rural 31.8 vs. urban 70.3%; P = 0.002). Unlike urban EMS, rural EMS did not routinely document scene time. CONCLUSION: Rural EMS responders' compliance to prehospital stroke evaluation/management was similar to urban EMS responders. Growth areas for both groups may be with prehospital stroke diagnostic tool utilization, whereas rural EMS responders may also improve with scene time documentation.

Endovascular Revascularization of a Symptomatic Common Carotid Artery Occlusion.

Although the common carotid artery is the second most common site for extracranial carotid artery stenosis, complete symptomatic occlusion in the absence of devastating stroke is rare. We present a case of complete common carotid artery occlusion failing medical management and requiring endovascular intervention. The clinical presentation, diagnostic investigations, and management of complete carotid artery occlusions are discussed.

The Combination of Clinical Features, Transcranial Doppler, and Alberta Stroke Program Early Computed Tomography Score (Computed Tomography Angiography) in Predicting Outcome in Intravenous Recombinant Tissue Plasminogen Activator-Treated Patients.

BACKGROUND: Little data exist on using combined baseline clinical neuroimaging and transcranial Doppler (TCD) information in predicting clinical outcome in stroke patients treated with intravenous (IV) thrombolysis. METHODS: Stroke patients received IV recombinant tissue plasminogen activator (rt-PA) and had diagnostic TCD within 3 hours of symptom onset. The TCD result was interpreted using the thrombolysis in brain ischemia (TIBI) flow grading system. Following multiple regression analysis, a grading system was created with 1 point for each of the following: National Institutes of Health Stroke Scale (NIHSS) score of 16 or higher, TIBI score of 1 or lower, and Alberta Stroke Program Early CT Score (ASPECTS) of 6 or lower. The patients' scores were compared to modified Rankin Scale (mRS) scores at 90 days. RESULTS: A total of 349 patients were included. In unvaried analysis, age of 80 years or older (P = .002), an ASPECTS of 6 or lower (P < .001), an NIHSS score of 16 or higher (P < .001), a TIBI score of 1 or lower (P < .001), and a glucose level ≥ 200 mg/dl (P = .04) were associated with poor outcome (mRS score > 2). In the multiple regression analysis, age of 80 years or older, an ASPECTS of 6 or lower, an NIHSS score of 16 or higher, and hyperglycemia were predictors of poor outcome (P < .05). Based on our scoring system, the patients' odds ratios for poor outcome were 7 (95% confidence interval [CI]: 2-23, P = .003), 8 (95% CI: 3-25, P < .001), and 24 (95% CI: 4-151, P = .001) for scores of 1, 2, and 3, respectively, after adjustment for common stroke risk factors. The mean time to recanalization increased as the score increased (score of 0: 160 ± 45 minutes versus score of 3: 186 ± 38 (P = .70). CONCLUSION: A multimodal grading system is useful in predicting outcome in patients treated with IV rt-PA. Those withhigher scores might be candidates for interventional therapy.

Improvement in thrombolytic therapy administration in acute stroke with feedback.

BACKGROUND: The benefits of intravenous recombinant tissue plasminogen activator (rt-PA) in acute ischemic stroke is time dependent. Guidelines recommend a door-to-needle (DTN) time of less than 60 minutes. METHODS: A retrospective audit of 730 stroke charts from 2008 - 2011 was conducted at Health Sciences Centre. 158 patients treated with IV rt-PA were identified. The time intervals between Emergency Department (ED) arrival, administration of rt-PA and uninfused brain computed axial tomographic scan (CT) were recorded. From this, CT to needle times were calculated. During November 2010 to January 2011 feedback was given to neurologists, ED physicians, ED nurses, and CT technologists. This raised awareness and emphasized the importance of this time driven protocol. RESULTS: The median DTN times for 2008, 2009, and 2010 were 69, 71 and 76 minutes respectively. The median CT-to-needle time for this time period was 47 minutes. In 2011 (n =58) the median DTN time was 49 minutes and the median CT-to-needle was 18 minutes, which were marked improvements (p<0.00005 and p<0.005, respectively). In 2008-2010 only 31% of treated patients (n=100) received rt-PA within 60 minutes, whereas in 2011 this increased to 64%. CONCLUSIONS: Dramatic improvements in DTN times and in the percentage of patients receiving rt-PA treatment within 60 minutes were observed in 2011 after feedback was provided regarding the suboptimal performance. Prior to receiving feedback, DTN times were similar to national median DTN times. All centres administering rt-PA for acute ischemic stroke should monitor their clinical performance and give feedback on a regular basis.