For patients suspected of having a large-vessel occlusion stroke, direct transport to a comprehensive stroke center for endovascular treatment may be preferable to initial transport to a nearer primary stroke center if the trip to the comprehensive center takes less than an hour.
The conclusion is based on the latest results of the RACECAT study, conducted in the Catalonia area of Spain.
RACECAT was a randomized controlled trial that sought to establish whether rates of favorable outcome for patients suspected of having acute large-vessel occlusion stroke were higher when the patients were transferred directly to an endovascular center (“mothership”) as compared to being taken first to a local stroke center for thrombolysis.
The main results of the trial, which were presented late last year, showed no clinical differences at 90 days between the two approaches in the overall population or in patients who had received a final diagnosis of ischemic stroke.
Secondary endpoints, which were presented at last week’s virtual International Stroke Conference (ISC) 2021, included results for patients who received an established diagnosis of large-vessel occlusion, patients who underwent endovascular therapy, and the effect of the transfer time.
“We found that direct transfer may improve odds of recovery for patients located within 60 minutes of a comprehensive stroke center. However, for patients located more than 60 minutes from a comprehensive stroke center, stopping at a local center may be more secure and efficient,” said lead investigator Natalia Pérez de la Ossa, MD, Hospital Germans Trias i Pujol, Barcelona, Spain.
“Especially for long distances, organizing a close, coordinated, and efficient stroke network with local and comprehensive stroke centers might be a good solution for rural areas, rather than planning a centralized transfer of all patients to a distant endovascular center,” she added.
In other secondary results from the study, the clinical outcomes of patients with confirmed large-vessel occlusion and patients who received endovascular therapy were similar regardless of whether the patients were transported directly to the comprehensive center or were first taken to a primary stroke center.
Pérez de la Ossa cautioned that the results from RACECAT are only applicable to systems with efficient time metrics. “Our results only apply to systems with good time performances at both local and endovascular centers, and they need to be tested in other places with different geographical and regional characteristics to help develop the optimal transfer protocols for severe stroke patients,” she concluded.
The RACECAT trial involved 1401 patients suspected of having large-vessel occlusion stroke, as determined by paramedics using the prehospital Rapid Arterial Occlusion Evaluation (RACE) scale (a score ≥5 was needed for inclusion) in a geographical area not served by a comprehensive stroke center. The patients were randomly assigned to be transferred either to a local hospital or to a comprehensive stroke center further away.
A final diagnosis of large-vessel occlusion stroke was established in 47% of the cohort; 22% had an ischemic stroke without a large-vessel occlusion; 23% had an intracerebral hemorrhage (ICH); and 8% had a stroke mimic. Median time to the endovascular center was 61 minutes.
In the trial, thrombolysis was given to 60% of patients taken to a local hospital first, with a time to thrombolysis of 120 minutes; 47% were taken directly to the endovascular center, with a time to thrombolysis of 155 minutes.
Endovascular therapy was performed in 39% of the local-hospital group, vs 49% of the direct-to-mothership group. Time to initiation of endovascular therapy was 270 minutes and 214 minutes, respectively.
The latest results showed that among patients diagnosed with a large-vessel occlusion, there was no difference in functional outcome for those taken directly to an endovascular center and for those taken first to a local hospital. A good functional outcome (Modified Rankin Scale score [mRS], 0–2) was achieved in 29.6% of those taken directly to the endovascular center, vs 31.3% of those taken first to a local hospital (adjusted odds ratio [aOR], 1.22; 95% CI, 0.89 – 1.69).
However, patients with a large-vessel occlusion who received tPA at the local hospital had better results than those taken directly to the endovascular center, with 33% achieving a good functional outcome (P = .07).
For patients who received endovascular treatment, again there was no difference regarding good functional outcomes between the two groups. For patients taken directly to the endovascular center, 34.1% achieved an mRS of 0–2, vs 32.1% for those taken first to the local center (aOR, 0.92; 95% CI, 0.67 – 1.35).
Pérez de la Ossa attributed this result to the relatively short difference in treatment times between the two groups. The time from symptom onset to start of endovascular treatment was 270 minutes for the those first taken to a local hospital, vs 214 minutes for those taken straight to the endovascular center.
“This time difference of about 55 minutes is quite short and is because the time metrics at the local centers were very good,” she commented.
Results by transport time suggest that patients who are within 60 minutes of an endovascular center may benefit from direct transfer to that center, but patients who are more than 60 minutes from the endovascular center would derive more benefit from being taken to the nearest local center, Pérez de la Ossa reported.
Commenting for Medscape Medical News, Tudor Jovin, MD, co-chair of the ISC session at which these latest results were presented, described some of the findings as “surprising.”
Jovin, who is chair of neurology at Cooper University Hospital, Cherry Hill, New Jersey, and who was an investigator in the RACECAT study, noted that it is important to remember that this study evaluated pathways for patients who were more than 30 minutes from a thrombectomy center.
“All the patients in this study would have normally been assigned to a nonthrombectomy center by default. If patients were within 30 minutes of a thrombectomy center, they would not have been included in this study.
“The main results showed no difference in outcomes in the overall population included,” he noted. “And now we see that among patients who actually had a large-vessel occlusion, the results surprisingly also showed no difference. Patients with a proven large-vessel occlusion stroke taken directly to a secondary thrombectomy-capable center did not show significantly better outcomes.”
These results, he added, “are really not what we were expecting. The study was designed to show a benefit of going directly to the thrombectomy center for patients with a suspected large-vessel occlusion.”
Jovin pointed out that the results may be explained by the “very impressive workflow times” in this study.
“Patients who were taken first to a primary center and then transferred to a thrombectomy center had very fast door in-out times (around 60 minutes), which are not typical for average stroke services. Going directly to a thrombectomy center is more likely to be beneficial in places where there are transfer delays,” he concluded.
The RACECAT trial was funded by Medtronic through an unrestricted grant to the Fundació Ictus Catalunya. Pérez de la Ossa received a grant from the PERIS program from the Catalan Health Government.
International Stroke Conference (ISC) 2021: Late-breaking abstract 5. Presented March 18, 2021.