“Fewer passes or attempts [means] less brain injury, lower likelihood of complications, and better outcomes,” researcher says.
Achieving recanalization in a single pass during mechanical thrombectomy for acute ischemic stroke is independently associated with better outcomes, according to a large database analysis published online February 19, 2018, ahead of print in Stroke.
“It is critical that we move the success target forward for improving both safety and efficacy of what we do,” lead author Osama O. Zaidat, MD (Mercy Health St. Vincent Hospital, Toledo, OH), told Neurovascular Exchange. “From the old days of defining success at TICI 2a, to higher at TICI2b (> 50% reperfusion) with three passes, to the proposal in this paper of substantial reperfusion of the brain tissue by a single pass or attempt—fewer passes or attempts [means] less brain injury, lower likelihood of complications, and better outcomes.”
Zaidat and colleagues used the North American Solitaire Acute Stroke Registry database to identify a subgroup of 89 out of 354 patients (25.1%) treated with thrombectomy for acute ischemic stroke who experienced the first pass effect, meaning complete recanalization with a single thrombectomy device pass.
There were some baseline and procedural differences between the patients who experienced first pass effect and those who did not. Notably, those treated during a single pass were more likely to have occlusions located in the middle cerebral artery (64% vs 52.5%) and less likely to have them in the internal carotid artery (ICA; 10.1% vs 27.7%). In addition, balloon guide catheters were used more frequently in patients who experienced the first pass effect (64.0% vs 34.7%), and their time to revascularization was significantly shorter (median 34 vs 60 minutes; P = 0.0003).
A significantly greater proportion of patients who experienced the first pass effect achieved a good outcome, defined as an mRS ≤ 2 at 90 days, as well as better National Institutes of Health Stroke scores (NIHSS) at discharge and reduced 90-day mortality.
Relationship Between First Pass Effect and Outcomes
|
|
With (n = 89) |
Without (n = 265) |
P Value |
|
90-Day mRS ≤ 2 |
61.3% |
35.3% |
0.013 |
|
Mean Discharge NIHSS Score (SD) |
9.1 (12.9) |
(16.0) |
0.0001 |
|
90-Day Mortality |
16.3% |
36.5% |
0.001 |
Multivariate analysis that controlled for age, ICA occlusion, baseline NIHSS, use of balloon guide catheters, symptomatic intracranial hemorrhage, and use of general anesthesia revealed that the presence of the first pass effect was an independent predictor of good outcome (OR 2.1; 95% CI 1.1-4.1; P = 0.03).
Independent predictors of achieving the first pass effect were use of balloon guide catheters (OR 3.5; 95% CI 2.0-6.2; P < 0.001) and the absence of ICA terminus occlusions (OR 0.23; 95% CI 0.09-0.57; P < 0.0001).
Regarding balloon guide catheters, Zaidat said, “we should consider higher utilization of this adjunctive tool to get more of the first pass effect.”
“This study adds evidence and confirms the mindset that ‘time is brain’,” Fatih Seker, MD (Heidelberg University Hospital, Heidelberg, Germany), told Neurovascular Exchange. “It also suggests using the first pass effect . . . as a surrogate for the effectiveness of a thrombectomy device,” he commented.
Seker and his team have themselves previously shown that the ability to obtain good clinical outcomes diminishes with each pass. “The strengths of the presented study of Zaidat et al are its size (n = 354) and the usage of Solitaire as the only stent-retriever,” he said.
Seker described the difference in outcomes seen in this study as “clinically relevant” and speculated on how the current findings might change clinical practice. For instance, the first pass effect might become an endpoint in studies evaluating thrombectomy devices, perhaps even affecting US Food and Drug Administration approval. This would put pressure on manufacturers to design devices that can be used to achieve a first pass effect most of the time.
In addition, he said, “the importance of achieving recanalization with one attempt underlines that neurothrombectomy needs to stay in the neurointerventional domain, in order to ensure high quality health are.”
Both Seker and Zaidat acknowledged that many questions remain. For instance, Seker wondered whether there is a meaningful difference in outcomes for patients who achieve reperfusion with one versus two passes. Also, he said, the role of balloon guide catheters remains unclear.
For his part, Zaidat wondered how frequently the first pass effect can be achieved with different techniques, including ADAPT and stent-retriever plus aspiration strategies, as well as whether there might be other predictors of this phenomenon.
Source:
Zaidat OO, Castonguay AC, Linfante I, et al. First pass effect: a new measure for stroke thrombectomy devices. Stroke. 2018;Epub ahead of print.
Disclosure:
Zaidat and Seker report no relevant conflicts of interest.
