Assessment of left atrial function following patent foramen ovale closure using four-dimensional auto left atrial quantification

To evaluate the application of four-dimensional auto left atrial quantification (4D Auto LAQ) technology in assessing left atrial (LA) function following transcatheter closure of a patent foramen ovale (PFO). In this prospective study, patients diagnosed with a PFO and scheduled for transcatheter closure at the First Affiliated Hospital of Xinxiang Medical University underwent transthoracic echocardiography and 4D Auto LAQ examinations before the procedure and at 1 day and 1, 3, 6 and 12 months after procedure. Left atrial structural parameters, volumetric parameters and strain parameters were measured. Repeated measures analysis of variance was used to analyse parameter changes over time. Thirty-two patients (13 men, 19 women; mean age: 44.0 ± 9.5 years) were included in the final analysis. Left atrial volume minimum increased significantly following closure (P = 0.007), whereas total LA ejection fraction (LAEF) and active LAEF decreased (P < 0.001 and P = 0.019, respectively). Several LA strain indices, including reservoir strain (LASr) and circumferential reservoir/conduit/contraction strains (LASr_c, LAScd_c and LASct_c), showed significant postoperative reductions (all P < 0.010). No significant differences were observed in other tracked measurements over time (all P > 0.050). The observed changes occurred early after closure and appeared to stabilise during subsequent follow-up. Four-dimensional auto left atrial quantification could provide a sensitive and non-invasive approach to evaluate LA volume and strain changes following PFO closure. Given the observational, non-comparative design, causal inference cannot be made; the detected alterations should be interpreted as hypothesis generating. Larger controlled studies incorporating clinical endpoints are warranted to determine the mechanisms and clinical relevance of these imaging changes.