IJCS | Volume 33, Nº4, July and August 2020

313 Figure 3 - Risk Ratios for transient ischemic attack in six major trials. CI: confidence interval. For references and trial acronyms, see text. Figure 2 - Risk Ratios for recurrent stroke in six major trials. CI: confidence interval. For references and trial acronyms, see text. Pereira et al. Patent foramen ovale in cryptogenic stroke Int J Cardiovasc Sci. 2020; 33(4):307-317 Original Article to show superiority of PFO closure over medical treatment to decrease stroke recurrence or TIA. 3,5,8 These relatively modest results have been attributed to several limitations, including choice of the closure device, off- protocol closure device use within the medical therapy arms, patient selection criteria, low sample size, slow enrolment, short duration of follow-up, 1,3,5,8 among other factors. Although in the first trials, PFO closure did not show greater benefit than medical therapy alone, more recent studies did observe its superiority. 6,9,10 The REDUCE trial had a smaller number of patients with uncontrolled vascular risk factors than previous trials with less rigorous exclusion criteria. For instance, the CLOSE and DEFENSE-PFO trials only included