Patent foramen ovale (PFO) is a risk factor for cryptogenic stroke (CS), and interventional therapy for PFO can reduce the recurrence rate of CS. However, interventional therapies are primarily guided by X-ray imaging, and regular postsurgical follow-up with transthoracic ultrasound foaming test (UFT) is rarely performed. Thus, this study aimed to assess the short-term (1 year) results of PFO occlusion guided by transoesophageal echocardiography (TEE) and the results of regular UFTs.
Clinical records, echocardiographic data, and UFT results of 27 patients who underwent interventional therapy for PFO and CS were retrospectively analysed. The patients were grouped according to their preoperative UFT results: group A (n = 4), small volume of right-to-left shunts; group B (n = 8), moderate volume of right-to-left shunts; and group C (n = 15), large volume of right-to-left shunts. All patients were treated using an Amplatzer occluder under TEE guidance. UFT follow-up was conducted regularly until 1 year post-surgery.
No significant differences in preoperative clinical data, echocardiographic data, or operative time were noted between the groups (P > 0.05). The length of the PFO and the diameter of the occluder differed between the groups as follows: group A = group B < group C (p < 0.05). One year postoperatively, there was no stroke recurrence. Two patients in group C developed atrial arrhythmia, which improved after 3 months of antiarrhythmic treatment. The positive UFT rate gradually decreased postoperatively, and 50% of patients still had a positive UFT 11.75 months after surgery. The positive UFT rate 1 year postoperatively differed between the groups as follows: group A = group B < group C (p = 0.010). A preoperative large-volume shunt was negatively associated with a negative UFT rate 1 year postoperatively (b=-2.118, RR = 0.120, p = 0.002).
In patients with PFO and CS, interventional therapy guided by TEE led to excellent short-term (1 year) outcomes. The positive UFT rate gradually decreased within 1 year of surgery. Preoperatively, a large volume of right-to-left shunts and large occluders were two risk factors for positive UFT results after surgery. Further studies are required to clarify the relationship between positive UTF results postoperatively and stroke recurrence.