Initial experience with the novel p64MW HPC flow diverter from a cohort study in unruptured anterior circulation aneurysms under dual antiplatelet medication

OBJECTIVE: p64MW HPC is a new low-profile flow diverter with reduced thrombogenicity due to hydrophilic coating. The purpose of this study was to evaluate its safety and efficacy in Mongolian patients under dual antiplatelet therapy. METHODS: Consecutive patients with unruptured anterior circulation aneurysms were prospectively enrolled. All patients received aspirin and clopidogrel before and six months after the procedure, followed by lifelong aspirin medication. High platelet reactivity (VerifyNow) did not trigger further action. The safety and efficacy endpoints were clinical outcome and aneurysm occlusion. RESULTS: In 29 patients (26 female, median age 57 years), 46 aneurysms (neck width 3.3 mm, fundus diameter 3.7 mm, median) were treated. Dual platelet function inhibition was confirmed in eight patients (28%). The response to Clopidogrel was between 100 and 239 P2Y12 reaction units (VerifyNow) in 13 patients (45%). Non-response to at least one drug was found in 8 of 29 patients (28%). One collapsed p64MW HPC required balloon angioplasty. No other periprocedural thrombus formation occurred. Postprocedural MRI revealed lesions with diffusion restriction in 3 of 29 patients. Digital subtraction angiography after three months for 42 of 46 (91%) aneurysms showed an adequate aneurysm occlusion in 25 (60%). Distal p64MW HPC migration of 3 implants was retreated with another p64MW HPC. Follow-up digital subtraction angiography of 26 of 46 (57%) aneurysms after six months showed adequate aneurysm occlusion in 22 (85%). Significant in-stent stenosis or thrombosis, morbidity or mortality was not encountered. CONCLUSION: p64MW HPC implantation in patients under dual antiplatelet therapy with or without dual platelet function inhibition has a low procedural complication rate. The early aneurysm occlusion rate is high.