Safety and efficacy of the p48 MW and p64 flow modulation devices: a systematic review and meta-analysis

Objective: Flow diverters (FDs) have demonstrated increasing safety and efficacy in treating various types of intracranial aneurysms. Although the underlying mechanism of action of all FDs is similar, differences are noted in their intrinsic characteristics, materials, and deployment techniques. The p64 flow modulation device (p64) and the newer p48 movable wire flow modulation device (p48 MW) are not yet available in the US but have been increasingly used mainly in Europe, demonstrating optimistic results. The authors performed a systematic review and meta-analysis of the literature to evaluate the safety and efficacy of the p64 and p48 MW FDs.

Methods: A literature review (between January 1960 and November 2022) of the PubMed, Scopus, Embase, Web of Science, and Cochrane Central Register of Controlled Trials databases was conducted. The primary efficacy outcome was the proportion of complete angiographic occlusion at last follow-up. Complete occlusion was defined as Raymond-Roy class 1 and O'Kelly-Marotta grade D. The primary safety outcomes were the composite safety rate of ischemic and hemorrhagic events (intra- and postprocedure) and the all-cause mortality rate. Data were analyzed using a random-effects proportions meta-analysis, and statistical heterogeneity was assessed.

Results: Twenty studies with 1781 patients harboring 1957 aneurysms were included in the analysis. Seventeen studies were conducted in Europe. Sixteen studies evaluated the performance of the p64 (MW). Patient ages ranged between 20 and 89 years, and most were female (78.7%). Aneurysm size ranged between 1 and 50 mm. Most aneurysms were unruptured (92.8%) and in the anterior circulation (93.1%). Single antiplatelet therapy pre- and postprocedure was used in 2 studies. Follow-up ranged from 2 to 14.5 months. For the p64 and p48 MW, complete angiographic occlusion rates were 77% (95% CI 68%-85%) and 67% (95% CI 49%-81%), adjunctive coil usage rates were 7% (95% CI 4%-12%) and 4% (95% CI 0%-24%), primary safety composite rates were 2% (95% CI 1%-4%) and 3% (95% CI 1%-11%), and mortality rates were 0.49% (95% CI 0%-1%) and 2% (95% CI 1%-6%), respectively.

Conclusions: The p64 and p48 MW have primarily been used in Europe thus far. This analysis found that both devices have an acceptable efficacy and favorable safety profile. However, further studies are needed to evaluate the efficacy and safety of prescribing a single antiplatelet regimen after implantation of the newer-generation FDs with antithrombotic coating surface modification.