Abstract P702: How Many Cryptogenic Stroke Patients Should Be Candidates for Patent Foramen Ovale Closure?

Background and Purpose: Recent several studies demonstrated that percutaneous patent foramen ovale (PFO) closure reduced the risk of stroke recurrence for patients with cryptogenic stroke (CS) and PFO. Our aim of this retrospective study is to survey the frequency of CS, which can be an indication of PFO closure. Methods: Subjects were consecutive stroke patients with symptomatic ischemic lesion detected by magnetic resonance imaging. Of them, CS were extracted according to exclusion of small-vessel collusion, large-artery atherosclerosis, cardioembolism, definite case of aortogenic embolism, and distinctive causeof ischemic stroke such as arterial dissection, hypercoagulable state and so on. After that, we selected patients in accordance with clinical guideline of PFO closure recommended by the Japanese Stroke Association (Figure). We analyzed the prevalence of CS with right-to-left shunt (RLS) as a good and recommended candidates for PFO closure. Results: Among 1,374 ischemic stroke patients from October 2012 to September 2019 , CS were 240 patients (83 females, mean age of 66 years, 17% of subjects). Of them, 100 patients (42%) had RLS (PFO; 65, atrial septal defect; 1, pulmonary arteriovenous fistula; 1, positive on transcranial Doppler (not performed in TEE) including 21 cases of definite of paradoxical embolism. In 65 patients of CS with PFO, 30 patients younger than 60 years (13% of CS) were good candidates for PFO closure. Moreover, 22 of 1,374 (1.6%) patients who were recommended candidates had one or more high risk factors of PFO, for example large shunt, atrial septal aneurysm, and the presence of shunt at rest (Figure). Conclusions: In our preliminary survey, 2% of acute ischemic stroke should be PFO closure candidates.