Related Experiment Video
Updated: Feb 13, 2026
Closure of a Patent Foramen Ovale PFO: An Intervention Sequence
Published on: December 23, 2022
Cryptogenic Stroke and High-Risk Patent Foramen Ovale: The DEFENSE-PFO Trial
Pil Hyung Lee1, Jae-Kwan Song1, Jong S Kim2
1Department of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Insights
Patent foramen ovale (PFO) closure significantly reduced stroke recurrence in patients with high-risk PFO characteristics. PFO closure is a safe and effective treatment for cryptogenic stroke prevention.
Area of Science:
- Cardiology
- Neurology
- Medical Devices
Background:
- Recent reports suggest patent foramen ovale (PFO) closure benefits cryptogenic stroke patients.
- Optimal candidate selection for PFO closure remains a critical issue.
Purpose of the Study:
- To evaluate if PFO closure benefits depend on specific PFO morphologic characteristics.
- Assessed PFO morphology via transesophageal echocardiography in cryptogenic stroke patients.
Main Methods:
- DEFENSE-PFO study randomized high-risk PFO patients (stroke + PFO with aneurysm, hypermobility, or ≥2mm size) to PFO closure or medication.
- Primary endpoint: composite of stroke, vascular death, or major bleeding over 2 years.
Main Results:
- 120 patients randomized; PFO characteristics were similar between groups.
- The primary endpoint occurred only in the medication-only group (12.9% vs. 0%; p=0.013).
- Ischemic stroke recurrence was significantly lower with PFO closure (10.5% vs. 0%; p=0.023).
Conclusions:
- PFO closure in high-risk PFO patients significantly lowers the rate of the primary composite endpoint.
- PFO closure demonstrated a reduced rate of stroke recurrence in this patient cohort.
Background:
Recent reports showing the favorable role of patent foramen ovale (PFO) closure in patients with cryptogenic stroke have raised the issue of selecting optimal candidates.
Objectives:
This study, DEFENSE-PFO (Device Closure Versus Medical Therapy for Cryptogenic Stroke Patients With High-Risk Patent Foramen Ovale), evaluated whether the benefits of PFO closure can be determined on the basis of the morphologic characteristics of the PFO, as evaluated by transesophageal echocardiography.
Methods:
Patients with cryptogenic stroke and high-risk PFO were divided between a transcatheter PFO closure and a medication-only group. High-risk PFO included PFO with atrial septal aneurysm, hypermobility (phasic septal excursion into either atrium ≥10 mm), or PFO size (maximum separation of the septum primum from the secundum) ≥2 mm. The primary endpoint was a composite of stroke, vascular death, or Thrombolysis In Myocardial Infarction-defined major bleeding during 2 years of follow-up.
Results:
From September 2011 until October 2017, 120 patients (mean age: 51.8 years) underwent randomization. PFO size, frequency of septal aneurysm (13.3% vs. 8.3%; p = 0.56), and hypermobility (45.0% vs. 46.7%; p > 0.99) were similar between the groups. All PFO closures were successful. The primary endpoint occurred exclusively in the medication-only group (6 of 60 patients; 2-year event rate: 12.9% [log-rank p = 0.013]; 2-year rate of ischemic stroke: 10.5% [p = 0.023]). The events in the medication-only group included ischemic stroke (n = 5), cerebral hemorrhage (n = 1), Thrombolysis In Myocardial Infarction-defined major bleeding (n = 2), and transient ischemic attack (n = 1). Nonfatal procedural complications included development of atrial fibrillation (n = 2), pericardial effusion (n = 1), and pseudoaneurysm (n = 1).
Conclusions:
PFO closure in patients with high-risk PFO characteristics resulted in a lower rate of the primary endpoint as well as stroke recurrence. (Device Closure Versus Medical Therapy for Cryptogenic Stroke Patients With High-Risk Patent Foramen Ovale [DEFENSE-PFO]; NCT01550588).
Related Concept Videos
01:12Trial and Error and Algorithm
01:11Clinical Trials: Overview
01:16Clinical Trials
There are four phases in a clinical trial. A phase one...
02:26Defenses Against Pathogens and Herbivores
01:31Defense Against Bacterial Pathogens
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
01:26Defense Mechanism Against Infection
In addition, many body organ systems have unique defenses against infection. The skin is an intact, multilayered surface preventing invasion by microorganisms unless impaired. Mucous membranes lining the mouth, nose, and eyelids are barriers...