Abstract
BACKGROUND: Closure of a patent foramen ovale (PFO) is an effective strategy in the prevention of recurrent stroke after cryptogenic stroke. Residual shunt (RS) is a common issue following PFO closure and may affect safety and efficacy. Transesophageal echocardiography (TEE) is the key diagnostic tool, but standardized assessment of morphological parameters to prevent RS remains challenging. AIMS: In this study, we investigate the diagnostic value of different anatomical parameters assessed by TEE to predict RS after PFO closure. METHODS: We consecutively enrolled five-hundred and twenty-seven (n = 527) patients undergoing PFO closure. We performed pre-interventional TEE, and after PFO closure, we then screened for RS by TEE at 6-month follow-up. RESULTS: Pre-interventional TEE measures of PFO morphology revealed significant differences in patients with RS in comparison to those with closed PFO. Incidence of RS was significantly more frequent in patients with atrial septum aneurysm (p = 0.022) and increasing PFO size (p = 0.025). In patients with RS, we found significantly increased length (p = 0.005) of septum primum and PFO tunnel (p = 0.036) as well as excursion (p = 0.005) of septum primum. By training machine learning models on TEE parameters, stratification of PFO morphology resulted in high diagnostic accuracy to predict RS after PFO closure. CONCLUSIONS: Our study elucidates that a baseline characterization of PFO morphology using TEE improves diagnostic precision to identify patients with RS after PFO closure. A standardized approach might thus enhance the efficacy and safety of transcatheter PFO closure. Prediction of complete closure might reduce complications and allow for a more refined patient selection and treatment.