First-line aspiration noninferior to stent retriever for acute ischemic stroke

Functional outcomes were noninferior for patients with acute ischemic stroke and emergent large-vessel occlusion who underwent treatment with a first-line aspiration technique, compared with a first-line stent retriever approach, researchers reported at the International Stroke Conference.

“Recent trials have demonstrated benefit of thrombectomy to treat stroke patients; however, the majority of those patients were treated with stent retrievers,” J. Mocco, MD, from Mount Sinai Hospital in New York, said during a press conference. “Single-arm data suggest that using aspiration instead of stent retriever as a first-pass approach to treating stroke has potential benefits with similar clinical outcomes and potentially superior technical results, less time and lower costs.”

The COMPASS trial (A Comparison of Direct Aspiration vs. Stent Retriever as a First Approach) was designed to assess whether a direct aspiration first-pass technique (ADAPT, Penumbra) does not have inferior clinical outcomes, compared with stent retriever as a first-line approach, in patients with large-vessel occlusions. The researchers also sought to evaluate differences in technical outcomes and costs, Mocco said.

COMPASS was a 1:1 randomized trial with blinded outcome assessment and blinded core lab adjudication of imaging that involved up to 20 centers. Each site was asked to submit data from the last 20 cases and both treatment modalities had to have been used in at least five cases each. Primary investigators attempted to select sites with consideration of balancing centers’ preferred approach in case reporting, according to Mocco.

Only FDA-approved devices were permitted and physicians were allowed to use their preferred adjunctive techniques.

Fifteen of 20 centers were activated and two additional centers were in the process of activation when enrollment completed.

A total of 270 patients were enrolled, with 134 patients in the aspiration arm and 136 in the stent retriever arm. Baseline demographics were well balanced between groups, Mocco said, with about one-third of patients having general anesthesia.

Intention-to-treat was the prespecified primary analysis. The primary efficacy outcome was function at 90 days as determined by modified Rankin Scale score. Safety endpoints included 90-day all cause mortality, 24-hour intracranial hemorrhage, 24-hour symptomatic intracranial hemorrhage and symptomatic intracranial hemorrhage using the SITS-MOST criteria.

In terms of procedural variables, balloon-guided catheters were used in 33.6% of patients in the ADAPT arm vs. 44.5% of patients in the stent retriever arm (P = .06) and distal access or a reperfusion catheter was used in 97.8% of patients in the ADAPT arm vs. 86.8% in the stent retriever arm (P = .001). It is also worth noting, Mocco said, that the percentage of patients achieving thrombolysis in cerebral infarction (TICI) 2b with the primary assigned treatment modality was 83% in the ADAPT arm and 81% in the stent retriever arm, suggesting no substantial need to move to additional treatment modalities.

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At 90 days, 52% (95% CI, 43.8-60.3) of patients in the ADAPT arm vs. 49% (95% CI, 41.6-57.4) of patients in the stent retriever arm achieved a modified Rankin scale score of 0 to 2 (P for noninferiority = .0014).

More patients in the ADAPT arm vs. the stent retriever arm achieved TICI 3 or greater within 45 minutes, although the finding was not statistically significant due to multiple comparisons (34% vs. 23%; P = .0486), Mocco said. Likewise, the time to reperfusion was faster in the ADAPT arm vs. the stent retriever arm, but the difference was again not statistically significant due to multiple comparisons (22 vs. 33 minutes; P = .0194).

Additionally, the percentage of patients achieving TICI scores of 2b or 2c were comparable in both arms. There was also a possible trend toward more TICI 3 in the ADAPT arm vs. the stent retriever arm (37.6% vs. 28.7%; P = .0154), according to Mocco.

In terms of safety, the rates of all-cause mortality at 90 days, all intracranial hemorrhage and both symptomatic intracranial hemorrhage endpoints were similar between groups.

“We now have level 1 evidence that stent retrievers and primary aspiration have equivalent clinical outcomes in emergent large-vessel occlusion,” he said.

At present, cost analyses are ongoing, Mocco said. He also noted that at the time of presentation, one particular center may have issues with consent for one patient in the trial that may result in slight changes in the data. – by Melissa Foster

Reference:

Mocco J. LB4. Presented at: International Stroke Conference; Jan. 24-26, 2018; Los Angeles.

Disclosure: Mocco reports he has ownership interest in Blockade Medical, Cardinal, Endostream, Rebound Medical, Apama, Viseon, 3Rivers Medical, Serenity, Synchron, Cerebrotech and he has served as a consultant or on the advisory board for Cerebrotech, The Stroke Project, Endostream, Rebound Medical, Viseon, 3Rivers Medical and Synchron. Penumbra provided grants that funded the trial.