Comparative Efficacy and Safety of Nitinol Versus Novel Fully Biodegradable Occluders for Transcatheter Patent Foramen Ovale Closure in Migraine Treatment: A Retrospective Cohort Study

Rui-lin Li¹Jingjuan Huang²Jie Ming³Hao Ying¹Wei Wen¹Yun-li Shen^1*Li Lin^1*Lin-xiang Lu^1*

• ¹Department of Cardiology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, Shanghai Municipality, China
• ²Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
• ³Department of Clinical Laboratory, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China

Background: Transcatheter closure of patent foramen ovale (PFO) has shown potential therapeutic benefits for clinical symptoms in selected patients with migraine. Nevertheless, the comparative effectiveness and safety of traditional nitinol versus fully biodegradable occluders remain to be fully elucidated and warrant further investigation. Materials and methods: This retrospective cohort study included 158 migraine patients with a confirmed patent foramen ovale (PFO) and a grade II-III right-to-left shunt (RLS) as determined by contrast-enhanced transthoracic echocardiography (cTTE), who underwent transcatheter PFO closure at Shanghai East Hospital, Tongji University, between October 2023 and January 2024. Based on the occluder type, patients were categorized into a nitinol group (n = 77) or a biodegradable group (n = 81). Clinical baseline characteristics, echocardiographic parameters, procedural data, safety outcomes, residual right-to-left shunt (RLS) grades, and migraine severity assessed using the Migraine Disability Assessment Scale (MIDAS) were compared between groups. The primary outcome was migraine relief (≥50% reduction in MIDAS score) following the procedure. Secondary outcomes included the incidence of safety-related events and the rate of residual right-to-left shunt.Results: Both the nitinol group and biodegradable groups showed significant reductions in MIDAS scores post-procedure with no significant difference in migraine relief between groups (P = 0.644, Kaplan-Meier analysis). Both occluders showed a high procedural success rate (100%) and similar safety profiles, with low rates of perioperative complications. The biodegradable occluder exhibited progressive degradation, with a significant reduction in size by 12 months, while maintaining closure efficacy. Residual right-to-left shunting was minimal in both groups, with RLS grades 0 and 1 observed in 82.35% of patients in the nitinol group and 78.87% in the bioabsorbable group at the 12month follow-up.Both biodegradable and nitinol PFO occluders were equally effective in alleviating migraine symptoms, with excellent procedural success and safety profiles. The biodegradable occluder demonstrated effective closure and gradual degradation, offering a promising alternative to nitinol occluders, especially for patients concerned about longterm foreign body implantation. These findings support the clinical utility of both occluder types in PFO-related migraine treatment, with individualized device selection based on patient preferences and clinical factors.