PC Trial: Clinical treatment or closure of patent foramen oval in cryptogenic stroke patients?

Background: The association between paradoxical embolism, including cryptogenic stroke, and the presence of patent foramen oval (PFO) has been found in previous clinical studies. However, the benefit of percutaneous PFO closure versus medical treatment is not clear, especially after the negative results of the randomized CLOSURE I trial. This study included patients with PFO and documented paradoxical embolism who were randomized to percutaneous PFO closure with the Amplatzer device versus standard medical treatment.

Methods and Results: 414 patients were enrolled in centers around the world with a history of cryptogenic stroke or paradoxical cerebral embolism not cerebral. The primary outcome was a composite endpoint of death, stroke, transient ischemic attack or peripheral embolism. About 23% of patients in both groups had septal aneurysm. The implant was a success in 96.9% of cases. Percutaneous closure of PFO was associated with a relative risk reduction (RRR) of the primary endpoint of 37%, not statistically significant (p = 0.34). There were also 80% RRR for stroke but also without statistical significance (p = 0.14). There were no differences in secondary outcomes of atrial fibrillation, bleeding or other complications between the two groups.

Conclusions and observations: Percutaneous closure of PFO was not superior to medical treatment in preventing recurrence of paradoxical embolism in patients with PFO. However, reducing the risk of stroke (80% RRR, NNT 40), although not statistically significant, may be clinically relevant if confirmed in other studies.

Editorial Comment: The negative result of the study in terms of demonstrating the benefit of practice (PFO closure) far from closing the discussion, revived the issue and proposes a new challenge to improve performance, achieve methodological and answer this question: What is the best way to treat cryptogenic stroke? 

Original title: The PC Trial: A Prospective, Randomized Trial of PFO Closure vs. Medical Therapy in Patients with Cryptogenic Embolism