Successful experience of transcatheter residual right-to-left shunting closure after patent foramen ovale occlusion.

Background: Residual shunt after patent foramen ovale (PFO) occlusion is associated with recurrent stroke, and limited literature address the specific management of such cases. Herein we report our experience with secondary interventional treatment.

Methods: From July 2020 to January 2023, patients who underwent PFO occlusion for more than one year with residual right-to-left shunting (rRLS) screened by contrast transthoracic echocardiography (cTTE) constituted the study population. A retrospective analysis of the basic, procedural, and follow-up data was performed.

Results: A total of 35 patients with large rRLS were admitted to our center. Fourteen patients underwent transcatheter rRLS closure. Transesophageal echocardiography (TEE) clearly showed the color blood flow profile, and cTEE showed a large rRLS in 12 cases. TEE showed a small outlet near the left exit of the rRLS, and cTEE showed a small rRLS in two cases. Type I rRLS accounted for 71.4%, residual PFO, and residual atrial septal defect (ASD) for 14.3%, respectively. Secondary transcatheter interventions were successful in 12 patients (85.7%). No complications were observed. Six cases of type I rRLS were closed with ASD occluders and two with an ADO-II device. Two residual PFO and two residual ASD were implanted with PFO occluders. cTTE was performed six months after the procedure, with complete closure in 12 patients.

Conclusion: TEE not only helps to improve interventional strategies to reduce residual shunt in primary occlusion but also helps in the screening of patients who are truly suitable for secondary intervention. ASD occluders can be considered as an alternative device for type I rRLS.