Mechanical thrombectomy for ischaemic stroke in the anterior circulation: off-hours effect

Endovascular stroke therapy outside core working hours in a nationwide stroke system

BACKGROUND

Endovascular therapy (EVT) has been established as a major component in the acute treatment of large vessel occlusion stroke. However, it is unclear whether outcome and other treatment-related factors differ if patients are treated within or outside core working hours.

METHODS

We analyzed data from the prospective nationwide Austrian Stroke Unit Registry capturing all consecutive stroke patients treated with EVT between 2016 and 2020. Patients were trichotomized according to the time of groin puncture into treatment within regular working hours (08:00-13:59), afternoon/evening (14:00-21:59) and night-time (22:00-07:59). Additionally, we analyzed 12 EVT treatment windows with equal patient numbers. Main outcome variables included favorable outcome (modified Rankin Scale scores of 0-2) 3 months post-stroke as well as procedural time metrics, recanalization status and complications.

RESULTS

We analyzed 2916 patients (median age 74 years, 50.7% female) who underwent EVT. Patients treated within core working hours more frequently had a favorable outcome (42.6% vs 36.1% treated in the afternoon/evening vs 35.8% treated at night-time; p=0.007). Similar results were found when analyzing 12 treatment windows. All these differences remained significant in multivariable analysis adjusting for outcome-relevant co-factors. Onset-to-recanalization time was considerably longer outside core working hours, which was mainly explained by longer door-to-groin time (p<0.001). There was no difference in the number of passes, recanalization status, groin-to-recanalization time and EVT-related complications.

CONCLUSIONS

The findings of delayed intrahospital EVT workflows and worse functional outcomes outside core working hours in this nationwide registry are relevant for optimization of stroke care, and might be applicable to other countries with similar settings.

Workflow Intervals and Outcomes of Endovascular Treatment for Acute Large-Vessel Occlusion During On-Vs. Off-hours in China: The ANGEL-ACT Registry

Background: There may be a delay in or a poor outcome of endovascular treatment (EVT) among acute ischemic stroke (AIS) patients with large-vessel occlusion (LVO) during off-hours. By using a prospective, nationwide registry, we compared the workflow intervals and radiological/clinical outcomes between patients with acute LVO treated with EVT presenting during off- and on-hours.

Methods: We analyzed prospectively collected Endovascular Treatment Key Technique and Emergency Work Flow Improvement of Acute Ischemic Stroke (ANGEL-ACT) data. Patients presenting during off-hours were defined as those presenting to the emergency department from Monday to Friday between 17:30 and 08:00, on weekends (from 17:30 on Friday to 08:00 on Monday), and on national holidays. We used logistic regression models with adjustment for potential confounders to determine independent associations between the time of presentation and outcomes.

Results: Among 1,788 patients, 1,079 (60.3%) presented during off-hours. The median onset-to-door time and onset-to-reperfusion time were significantly longer during off-hours than during on-hours (165 vs. 125 min, P = 0.002 and 410 vs. 392 min, P = 0.027). The rates of successful reperfusion and symptomatic intracranial hemorrhage were similar in both groups. The adjusted odds ratio (OR) for the 90-day modified Rankin Scale score was 0.892 [95% confidence interval (CI), 0.748–1.064]. The adjusted OR for the occurrence of functional independence was 0.892 (95% CI, 0.724–1.098), and the adjusted OR for mortality was 1.214 (95% CI, 0.919–1.603).

Conclusions: Off-hours presentation in the nationwide real-world registry was associated with a delay in the visit and reperfusion time of EVT in patients with AIS. However, this delay was not associated with worse functional outcomes or higher mortality rates.

Clinical Trial Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03370939.

Factors Associated With Decreased Accuracy of Modified Thrombolysis in Cerebral Infarct Scoring Among Neurointerventionalists During Thrombectomy

Background and Purpose

The modified Thrombolysis in Cerebral Infarct (mTICI) score is used to grade angiographic outcome after endovascular thrombectomy. We sought to identify factors that decrease the accuracy of intraprocedural mTICI.

Methods

We performed a 2-center retrospective cohort study comparing operator (n=6) mTICI scores to consensus scores from blinded adjudicators. Groups were also assessed by dichotomizing mTICI scores to 0–2a versus 2b–3.

Results

One hundred thirty endovascular thrombectomy procedures were included. Operators and adjudicators had a pairwise agreement in 96 cases (73.8%). Krippendorff α was 0.712. Multivariate analysis showed endovascular thrombectomy overnight (odds ratio [OR]=3.84 [95% CI, 1.22–12.1]), lacking frontal (OR, 5.66 [95 CI, 1.36–23.6]), or occipital (OR, 7.18 [95 CI, 2.12–24.3]) region reperfusion, and higher operator mTICI scores (OR, 2.16 [95 CI, 1.16–4.01]) were predictive of incorrectly scoring mTICI intraprocedurally. With dichotomized mTICI scores, increasing number of passes was associated with increased risk of operator error (OR, 1.93 [95 CI, 1.22–3.05]).

Conclusions

In our study, mTICI disagreement between operator and adjudicators was observed in 26.2% of cases. Interventions that took place between 22:30 and 4:00, featured frontal or occipital region nonperfusion, higher operator mTICI scores, and increased number of passes had higher odds of intraprocedural mTICI inaccuracy.

Off-hour effect is not significant in endovascular treatment for anterior circulation large vessel occlusion in a multicentre registry

Background and purpose

Whether the off-hour effect has an impact on workflow and outcomes of endovascular treatment (EVT) for anterior circulation large vessel occlusion (AC-LVO) remains uncertain. This study aimed to compare the characteristics and outcomes of patients who presented or were treated during off-hour versus on-hour in a multi-center registry.

Methods

AC-LVO patients from 21 centres were categorised into the off-hour group and the on-hour group. Off-hour (weekends, holidays, and 18:00–7:59 on weekdays) and on-hour (8:00–17:59 on weekdays except for holidays) were defined according to arrival and groin-puncture time points, respectively. Subgroup comparisons between patients both arrived and treated during off-hour (true off-hour) and on-hour (true on-hour) were performed. The primary outcome was the 90-day modified Rankin Scale (mRS) score. Secondary outcomes included favourable outcome (mRS 0–2 at 90 days), EVT-related time metrics, and other clinical outcomes. Ordinary and binary logistic regression and linear regression were taken to adjust for confounding factors.

Results

Of all 698 patients enrolled, 435 (62.3%) and 456 (65.3%) patients were categorised into the off-hour arrival and off-hour puncture group, respectively. Shorter onset to door time (adjusted ß coefficient: −21.56; 95% CI −39.96 to −3.16; p=0.022) was noted in the off-hour arrival group. Ordinal and dichotomous mRS scores at 90 days were comparable between the off-hour group and the on-hour group regardless of off-hour definitions. Other time metrics and outcomes were comparable between the two groups. Of 595 patients both presented and were treated during off-hour or on-hour, 394 patients were categorised into the true off-hour group and 201 into the true on-hour group. Time metrics and clinical outcomes were similar between the true off-hour and the true on-hour group.

Conclusions

The off-hour effect was not significant regarding clinical outcomes and in-hospital workflow in AC-LVO patients receiving EVT in this Chinese multicentre registry.

Off-hour effect on time metrics and clinical outcomes in endovascular treatment for large vessel occlusion: A systematic review and meta-analysis

BACKGROUND

There is an ongoing debate on the off-hour effect on endovascular treatment (EVT) for acute large vessel occlusion (LVO).

AIM

This meta-analysis aimed to compare time metrics and clinical outcomes of acute LVO patients who presented/were treated during off-hour with those during working hours.

SUMMARY OF REVIEW

Structured searches on the PubMed, Embase, Web of Science, and Cochrane Library databases were conducted through 23 February 2021. The primary outcomes were onset to door (OTD), door to imaging, door to puncture (DTP), puncture to recanalization, procedural time, successful recanalization, symptomatic intracranial hemorrhage (SICH), mortality in hospital, good prognosis (90-day modified Rankin Scale (mRS) score 0-2), and 90-day mortality. The secondary outcomes were imaging to puncture (ITP), onset to puncture (OTP), onset to recanalization (OTR), door to recanalization (DTR) time, mRS 0-2 at discharge, and consecutive 90-day mRS score. The odds ratio (OR) and weighted mean difference (WMD) with 95% confidence interval (CI) of the outcomes were calculated using random-effect models. Heterogenicity and publication bias were analyzed. Subgroup and sensitivity analyses were conducted as appropriate. Nineteen studies published between 2014 and 2021 with a total of 14,185 patients were eligible for quantitative synthesis. Patients in the off-hour group were significantly younger than those in the on-hour group and with comparable stroke severity and intravenous thrombolysis rate. The off-hour group had longer OTD (WMD [95% CI], 12.83 [1.84-23.82] min), DTP (WMD [95% CI], 11.45 [5.93-16.97] min), ITP (WMD [95% CI], 10.39 [4.61-16.17] min), OTP (WMD [95% CI], 25.30 [13.11-37.50] min), OTR (WMD [95% CI], 25.16 [10.28-40.04] min), and DTR (WMD [95% CI], 18.02 [10.01-26.03] min) time. Significantly lower successful recanalization rate (OR [95% CI], 0.85 [0.76-0.95]; p = 0.004; I²= 0%) was detected in the off-hour group. No significant difference was noted regarding SICH and prognosis. But a trend toward lower OR of good prognosis was witnessed in the off-hour group (OR [95% CI], 0.92 [0.84-1.01]; p = 0.084; I²= 0%).

CONCLUSIONS

Patients who presented/were treated during off-hour were associated with excessive delays before the initiation of EVT, lower successful reperfusion rate, and a trend toward worse prognosis when compared with working hours. Optimizing the workflows of EVT during off-hour is needed.