OCT‑Detected Endocardial Abnormality and Minimal Tunnel Area in Patients With Patent Foramen Ovale: Associations With Thrombus Formation

BACKGROUND: In situ thrombus formation represents one of the key pathogeneses of patent foramen ovale (PFO)‑related disorders. This study aimed to explore factors contributing to in situ thrombus in patients with PFO‑related diseases. AIMS: This study aimed to explore factors contributing to in situ thrombus in patients with PFO-related diseases. METHODS: Forty‑six prospectively enrolled patients with PFO‑related disorders underwent OCT imaging to explore potential contributing factors for in situ thrombus. None of the enrolled participants presented with concomitant lower‑extremity venous thrombosis or atrial fibrillation, and no alternative pathogenic factors were detected. RESULTS: In 63.04% of the cases (29 individuals), an in situ thrombus was present in the PFO tunnel. Patients with in situ thrombus exhibited a notably smaller right PFO area and minimum area, along with a higher incidence of abnormal endocardium than those without thrombus. Multivariate logistic regression analysis identified PFO minimum area and abnormal endocardium as independent factors associated with in situ thrombus. CONCLUSIONS: Our exploratory analysis suggests that endocardial abnormality and a smaller minimal PFO‑tunnel area may correlate with a higher risk of thrombus formation, offering clues regarding possible mechanisms behind PFO‑related diseases.