Background: The correlation between atrial septum anatomy and the risk of ischemic neurological events remains underexplored.
Aims: This study aimed to examine both the functional and anatomical attributes of the atrial septum and identify predictors of stroke and/or transient ischemic attack (TIA) in patients diagnosed with patent foramen ovale (PFO).
Methods: A total of 155 patients diagnosed with PFO, with a cardiological cause of neurological events, were enrolled. Transesophageal echocardiography was utilized to assess the anatomy of the PFO canal, size of the right-to-left shunt, thickness of the primary and secondary atrial septum, presence of atrial septum aneurysm, and anatomical structures of the right atrium.
Results: Regression analysis showed that factors such as female sex, hypercholesterolemia, PFO canal width, and a large right-to-left shunt were significantly associated with stroke and/or TIA. Receiver operating characteristic analysis indicated that the width of the PFO canal holds a relatively weak, although significant predictive, value for ischemic neurological episodes (area under the curve = 0.7; P = 0.002). A PFO canal width of 4 mm was associated with 70% sensitivity and 55% specificity for predicting stroke and/or TIA.
Conclusions: The atrial septum's anatomy, especially the dimensions of the PFO canal and the magnitude of the right-to-left shunt, combined with specific demographic and clinical factors, are linked to ischemic neurological incidents in PFO patients.
Keywords: atrial septum; patent foramen ovale; stroke; transient ischemic attack.