Aims: To evaluate the relationship between the anatomic features of the fossa ovalis (FO) and residual right-to-left shunt (RLS) after percutaneous patent foramen ovale (PFO) closure with AMPLATZER PFO occluder devices.
Methods and results: FO anatomic features were assessed by intracardiac echocardiography in 127 patients with large RLS at contrast-enhanced transcranial colour Doppler (TCCD) undergoing percutaneous PFO closure with an AMPLATZER device. Residual RLS was evaluated by TCCD three and 12 months after the procedure. PFO closure was successful in all but two patients. At TCCD, a significant residual RLS (grade ≥2) was observed in 27 (21.6%) and 17 (13.6%) patients at three and 12 months, respectively. Larger baseline RLS, presence of atrial septal aneurysm, greater longitudinal and transverse FO dimensions, and use of larger devices were associated with significant residual RLS. At multivariate analysis, the presence of atrial septal aneurysm (OR 7.6; 95% CI: 1.38-42.35; p=0.02) and longitudinal FO dimension >20.8 mm (OR 8.5; 95% CI: 1.55-46.95; p=0.014) were identified as independent predictors of significant residual RLS at 12 months.
Conclusions: Our study suggests that a large FO and the presence of atrial septal aneurysm are independent predictors of persistent residual RLS after PFO closure with AMPLATZER devices.