Complex Patent Foramen Ovale: Anatomic Variants, Technical Considerations, and Outcomes.

Patent foramen ovale (PFO) closure is a common intervention aimed at reducing recurrent stroke in patients with cryptogenic embolism. Complex PFO anatomies, characterized by features such as long tunnels, large defect sizes, atrial septal aneurysms, multifenestrated septa, prominent Eustachian valves or Chiari networks, and rigid or thickened septal tissue, pose significant challenges for successful device deployment and closure. Advances in imaging technologies, including transesophageal echocardiography, intracardiac echocardiography, and 3-dimensional imaging, have significantly enhanced the detection and characterization of these complex variants. This review summarizes contemporary evidence and procedural approaches tailored to overcome anatomic complexities, highlighting techniques such as tunnel angioplasty and transseptal puncture, alongside device selection considerations. Such advancements have led to acceptable procedural success rates and favorable long-term clinical outcomes. Ongoing innovations and dedicated research are essential to optimize these techniques further, improving patient safety and efficacy in complex PFO closure procedures.