In patients who’ve had a large core stroke, the benefits of thrombectomy can continue to increase out to 1-year follow-up, new results from the SELECT2 trial showed.
Other new data from the trial show that thrombectomy improved functional outcomes across a wide spectrum of ischemic core sizes compared with medical management only and that benefit of thrombectomy was seen even in patients who were already found to have a large core stroke when evaluated at an outside hospital and transferred for the procedure.
“These latest results from SELECT2 have implications for clinical practice in how we care for patients with large core strokes,” lead investigator Amrou Sarraj, MD, professor of neurology at University Hospitals Cleveland Medical Center-Case Western Reserve University in Cleveland, Ohio, told theheart.org | Medscape Cardiology.
“Our findings of continued improvement out to 1 year suggest that we need to give these patients with large core strokes time to allow their recovery to take its course. In this regard, continued supportive care and rehabilitation may be helpful for longer periods than we may sometimes currently provide,” he said.
Other results from the trial showing benefit can extend to patients with very large ischemic cores, and even to those who need to be transferred for thrombectomy, “show that we should not necessarily exclude these patients from the opportunity of receiving endovascular therapy,” he added.
These latest results from SELECT2 were reported in three separate presentations at the recent International Stroke Conference 2024 and simultaneously published as separate papers.
The SELECT2 trial, first reported last year, was one of several new trials to establish that thrombectomy can benefit stroke patients with large core volumes. The main results showed a better functional outcome at 3 months in patients treated with thrombectomy than those receiving medical management alone.
One-Year Results
The 1-year results from the trial, published online in The Lancet, showed the thrombectomy group continued to have improved modified Rankin Scale (mRS) score distribution vs medical care alone, as well as improved rates of good functional outcomes, defined as mRS scores of 0-2 or 0-3.
In addition, 28% of patients in the thrombectomy group vs 19% in the control group showed at least a one-point improvement in functional status on the mRS score between 3 months follow-up and 1 year. Quality-of-life scores were also better with thrombectomy at 1-year follow-up, suggesting not only long-term functional but also long-term social benefits of thrombectomy, the SELECT2 researchers reported.
“Because this population has had large core strokes, it is plausible that they will take a longer time for recovery to happen than patients with smaller strokes, and that is what we found,” Sarraj commented.
He said these results show that stroke clinicians need to be looking at outcomes in stroke patients further than 3 months out and should be open to further opportunities for recovery over the longer term, particularly in patients who have had a larger stroke.
“I think sometimes we may give up too early on these patients and start to think about palliative care, but our results show that further improvements are possible out to a year,” Sarraj added.
In a “Comment” accompanying The Lancet publication, Arturo Consoli, MD, the University of Versailles Saint-Quentin-des-Yvelines, Versailles, France, and Benjamin Gory, MD, Université de Lorraine, Nancy, France, said: “The stability of the rate of favorable clinical outcomes observed at 1 year shows the consistent and durable benefit of endovascular thrombectomy in patients with large ischemic cores.”
But they added that further studies will be necessary to better identify the subgroups for whom the highest rates of effectiveness and safety are observed.
Benefit Regardless of Core Size
Another analysis, published online in JAMA, looked at subgroups classified by the size of the stroke’s ischemic core. This showed that thrombectomy appeared beneficial compared with medical management alone across a wide spectrum of ischemic injury extent, even in those patients with the largest core strokes included in the trial (defined as an ASPECTS score of 3, or an ischemic core of 150 mL or larger).
However, as would be expected, clinical outcomes worsened as presenting ischemic injury estimates increased.
“There are always questions on how large is a large core stroke and is there a core size where patients no longer get any benefit from thrombectomy?” Sarraj explained.
“Ultimately, our results show without a doubt that reperfusion beats no reperfusion. Opening the blood vessel improves outcomes compared with not opening the vessel,” he commented. “But what is considered an acceptable outcome in a certain clinical situation is something that we may have to discuss with the patients’ families.”
The researchers report various probabilities of achieving an mRS score of 0-3 (walking independently) which Sarraj noted is probably the most reasonable accepted outcome in patients with large core strokes, and these were then stratified by the different core sizes and other clinical variables such as patient age and time to reperfusion.
“We can see that as the core size increases, as the age increases, and as the time to reperfusion increases, the probability of achieving an mRS score of 0-3 decreases,” Sarraj noted.
“This trial and other similar trials should lead to patients with large core strokes getting thrombectomy. That needs to happen. But at the same time, we do sometimes have to put things into context with the age of the patient and the time to reperfusion also taken into account, together with the families to make decisions about whether thrombectomy will be the right decision.”
In an editorial accompanying the JAMA publication, Umberto Pensato, MD, Humanitas University, Milan, Italy; Ronda Lun, MD, Stanford Healthcare, Stanford, California; and Andrew Demchuk, MD, University of Calgary, Calgary, Alberta, Canada, said the current findings mark a significant advancement in treatment for patients with medium-to-large cores, suggesting that a simpler imaging approach may suffice for patient selection. But they point out that the rates of poor functional outcomes are, regrettably, consistently high across all large core trials (mRS score, ≥ 4 in 53%-69%).
“Clinicians need to better discern which patients derive benefit from endovascular therapy when such large proportions of patients are destined for poor outcomes,” they stated.
Although the clinical benefit of endovascular therapy is maintained across the full spectrum of core volumes in this study, they pointed out that the anticipated functional outcomes are increasingly dire, especially since benefits are no longer significant for patients with core volumes greater than 100 mL and the outcomes appear futile when core volumes approach 200 mL.
“Additionally, caution should be exercised for very elderly patients, particularly when considering the impact of advancing age on the decreased likelihood of achieving favorable functional outcomes,” they added.
Transfer Patients Can Still Benefit
Finally, a third analysis, published online in JAMA Neurology, showed the beneficial effect of thrombectomy was observed in both directly presenting patients and in those who were transferred in from an outside hospital. But the benefits were lower in patients with transfer times of 3 hours or more.
The researchers point out that patients with large ischemic core stroke have poor clinical outcomes and are frequently not considered for interfacility transfer for endovascular thrombectomy.
“These findings may impact stroke systems of care infrastructure, highlighting the need for rapid identification of patients suitable for transfer and expedited transport and reperfusion on arrival,” they said.
“Sometimes clinicians when making the decision whether to transfer for thrombectomy or not may feel the stroke looks too large and it will take too long for there to be any benefit,” Sarraj added. “We found that there was still benefit in these patients, but the longer the transfer took, the more stroke evolution happened, then the worse the outcome. So, we all need to work on improving our transfer times.”
The SELECT2 trial was supported by an investigator-initiated grant from Stryker Neurovascular to University Hospitals Cleveland Medical Center and the University of Texas McGovern Medical School.