Penumbra Stroke System Shows Real-World Efficacy in Acute Ischemic Stroke Revascularization

In the largest prospective study evaluating the Penumbra system, 87.4% of patients achieved postprocedure modified Thrombolysis in Cerebral Infarction scores between 2b to 3.

Patients with large vessel occlusion (LVO)–acute ischemic stroke (AIS) who used the Penumbra system (Alameda) as a frontline mechanical thrombectomy (MT) treatment, demonstrated comparable angiographic, clinic, and safety outcomes in a real-world setting to those observed in prior randomized clinical trials.

The study, termed COMPLETE (NCT03464565), was a global, prospective, multicenter, single-arm, postmarket registry led by Osama O. Zaidat, MD, vascular neurologist, Mercy Health, that evaluated the performance of the Penumbra system in 650 patients with LVO-AIS. The primary efficacy end points were angiographic revascularization of the occluded target vessel at immediate postprocedure defined by modified Thrombolysis in Cerebral Infarction (mTICI) score of at least 2b and functional subject outcome at 90 days postprocedure defined as modified Rankin Scale (mRS) score 0 to 2.

Patients were grouped into 3 cohorts: cohort A (anterior LVO with Alberta Stroke Program Early CT Scores [ASPECTS] ≥6), cohort B (anterior LVO with ASPECT <6), and cohort C (posterior LVO). Cohort A was used as the main sample to conduct all end point measures, whereas exploratory analyses were done in cohorts B and C. At the final follow-up, the completion rate was high (94.6%), with the attrition rate (5.4%) that was better than the expected 10%. Most patients (52.8%) were transferred from another hospital, and 49.2% received intravenous recombinant tissue-type plasminogen activator before thrombectomy.

Successful revascularization, indicated by mTICI scores 2b-3, were achieved in 56.8% of cases post-first pass, 76.4% post-Penumbra system, and 87.8% (95% CI, 85.3-90.4) postprocedure. At 90 days, the all-cause mortality was 15.5% (95% CI, 12.8-18.3). Functional outcome, defined as mRS score 0-2, at 90 days was 55.8% (95% CI, 51.9-59.7). First pass and postprocedure rate of mTICI 2b to 3 were 41.5% and 66.2%, respectively.

READ MORE: IVT Bridging Therapy Outperforms Mechanical Thrombectomy in Reducing Thrombus, Clot Size

Zaidat et al wrote, "strengths of the COMPLETE registry include the prospective nature, the large sample size, the use of an imaging core lab and independent medical reviewers, and the inclusion of a variety of sites and operator experience levels to more accurately reflect real-world clinical practice.”

The Penumbra system is a fully integrated system engineered for effective clot removal and is intended for patients with AIS secondary to intracranial LVOs. It is comprised of several devices, including the Penumbra JET 7 and Penumbra JET D Reperfusion Catheters, ACE Reperfusion Catheters, MAX Reperfusion Catheters, 3D Revascularization Device, Penumbra ENGINE aspiration source, Penumbra ENGINE Canister, and Hi-Flow Aspiration Tubing.

Within 24 hours of the procedure, device-related serious adverse events (SAE) were found in 0.6% (n = 4) of cases, while 5.8% experienced procedure-related SAE and 9.1% (n = 59) experienced neurological deterioration. Additionally, throughout that time period, 3.8% (n = 25) of patients experienced symptomatic intracerebral hemorrhage (sICH) and 36.5% experienced any type of ICH.

Investigators noted that the lack of randomized comparison group as a limitation to the study, as well as the ability to enroll emergent cases after the procedure, and the absence of an independent certified assessor to evaluate mRS outcomes.

REFERENCE
Zaidat OO, Fifi JT, Nanda A. Endovascular treatment of acute ischemic stroke with the Penumbra System in routine practice: COMPLETE registry results. Stroke. Published online September 22, 2021. doi:10.1161/STROKEAHA.121.034268