Residual shunt after endovascular patent <i>foramen ovale</i> closure: in-hospital outcomes and clinical predictors

Aim. To study the in-hospital outcomes of patients with residual shunt (RS) through the occluder and identify predictors of its formation after endovascular patent foramen ovale (PFO) closure. Material and methods. We analyzed the data of 276 patients who underwent endovascular PFO closure for the period 2018-2023 at the Chazov National Medical Research Center. All patients underwent a scope of examinations that complied with clinical recommendations. RS in the postoperative period was assessed based on Transesophageal echocardiogram bubble study. Univariate regression analysis revealed RS predictors. Results. RS in the postoperative period was visualized in 50 patients, who, in terms of the incidence of in-hospital complications, were comparable to 226 patients without RS (p>0,05). Univariate regression analysis revealed the following indicators associated with postoperative RS: implantation of the Amplatzer PFO or Figulla Flex UNI occluder (odds ratio (OR) 8,87; 95% confidence interval (CI): 3,09-25,49), Chiari network (OR 8,26; 95% CI: 1,91-35,81), Olivares-Reyes class >3 interatrial septum aneurysm (OR 2,37; 95% CI: 1,27-4,43), as well as LAVi ≥34 ml/m 2 (OR 4,01; 95% CI: 1,33-12,09) (p<0,05). Conclusion. The use of Amplatzer PFO or Figulla Flex UNI occluders, the presence of a Chiari network, signs of left atrium dilatation, and Olivares-Reyes class >3 aneurysm were significant RS predictors.