Patent foramen ovale prevalence in atrial fibrillation patients and its clinical significance; A single center experience

Background: Patent foramen ovale (PFO) has been reported in 25–30% of the general population. The most commonly used test for detecting PFO is a contrast enhanced transesophageal echocardiography (TEE). PFO presence can be confirmed during pulmonary vein isolation (PVI) procedure by passing the transseptal catheter assembly through the foramen ovale, crossing the septum from the right to the left atrium without using a trans-septal needle for puncture. Methods: We retrospectively reviewed data from a cohort of 178 patients with AF who underwent PVI at Saint Louis University. Pre-PVI procedure, scheduled TEE reports were reviewed to assess for the presence of PFO and the PVI procedure reports were reviewed for confirmation. Results: Records of 178 patients (55.6% male, mean population age 60.4 ± 11.8) were reviewed. 102 of 178 patients had a PFO detected during the PVI procedure. This translates into a 57.3% prevalence of PFO in AF patients. Out of the 178 patients, 75 patients had a pre-PVI procedure TEE for whom PFO presence was reported in 18.7%. The sensitivity and specificity of TEE in detection of PFO were 36.8% and 100%, respectively. There was no statistically significant association between stroke and PFO diagnosed during PVI (RR 1.07; 95% CI, 0.53–2.19; P = 0.805). Conclusions: Our study reports a PFO prevalence of 18.7% using a pre-procedure TEE and 56.6% during the PVI procedure in AF patients. Given that TEE is the gold standard for detection of PFO, our study suggests that the prevalence of PFO may be underestimated in our AF population.