Early clinical experience with the p48MW HPC and p64MW HPC flow diverters in the anterior circulation aneurysm using single anti-platelet treatment

Abstract

Background: The p64MW HPC and p48MW HPC flow diverters have reduced thrombogenicity due to hydrophilic coating. The purpose of this study was to evaluate its safety and efficacy in Mongolian patients under single antiplatelet therapy (SAPT) with prasugrel.

Materials and methods: We performed a retrospective review of patients enrolled into our prospectively maintained database to identify all patients treated with either the p48MW HPC or p64MW HPC under SAPT. We recorded baseline demographics, aneurysm size and location, procedural complications, angiographic and clinical results.

Results: 24 patients, (female = 21, 87.5%), age 48.2 ± 11.6 years (range 25-63) underwent treatment of 30 aneurysms with either p64MW HPC or p48MW HPC. All aneurysms were saccular with dome width 8.2 ± 6.5 (range 1.6-26.0 mm) and dome height 7.6 ± 6.7 (range 1.6-30.0 mm). None of the aneurysms were previously treated. The average PRU was 54.6 ± 31.2 (range 1-127) on pre-operative VerifyNow testing. Angiographic follow-up was available for 13 patients (17 aneurysms), 183 ± 36 days post-procedure, at which point 64.7% of aneurysms (n = 11/17) were completely occluded and 11.8% (n = 2/17) had only neck remnants resulting in 76.5% of aneurysms being adequately occluded A single intra-operative complication (4.2%) occurred however all patients were mRS ≤1 at last follow-up. There were two post-operative complications neither of which resulted in permanent neurological morbidity. There were no instances of post-operative aneurysmal rupture or delayed parenchymal haemorrhage. The overall mortality was 0%.

Conclusion: The efficacy and safety of p64MW HPC coated devices under SAPT is similar to uncoated flow diverters that require DAPT.

Keywords: flow diverter; hydrophilic polymer coating; p48 MW HPC; p64 MW HPC; single antiplatelet therapy.

Figure 1.

Example case of a patient (patient number 6) with a large multilobulated para-ophthalmic aneurysm (a) treated with a single p64MW HPC (b) showing persistent filling of the aneurysm on angiography performed after implantation of the device (c). An MRI scan performed 24 hours post procedure did not show any DWI restricted lesions (d). Delayed MRA and catheter angiography showed complete occlusion of the aneurysm (e, f).

Figure 2.

Final imaging of a p64 HPC 4x12mm device from the ICA into the M1 segment showed good wall apposition (a). On follow-up angiography marked fish-mouthing was noted of the distal end of the device (b). Angioplasty using a Neurospeed 2x15mm balloon (Acandis) (c) was performed which resulted in a significant improvement in the appearance of the fish-mouthing (d) with good flow through the device and no complications (e).