Is Surgical Closure of Patent Foramen Ovale the Gold Standard for Treating Interatrial Shunts? An Echocardiographic Follow-up Study

Background Surgical closure of patent foramen ovale (PFO) has been considered definitive and the gold standard for preventing recurrent paradoxical embolism. However, in contrast to transcatheter PFO closure, patients undergoing operation have not systematically been re-evaluated for residual shunting. This study aimed to assess the efficacy of surgical PFO closure during follow-up by transesophageal echocardiography (TEE). Methods Eleven adult patients with diagnosis of a PFO by contrast and/or color Doppler TEE underwent PFO closure by thoracotomy and direct suturing because of paradoxical embolism (n = 4), because of impending paradoxical embolism (n = 1), or during valve operation (n = 6). Results TEE performed 5 days to 7 months after PFO closure revealed residual shunting in 8 of 11 patients (73%). The shunt size was unchanged in two patients. According to the color Doppler jet width across the atrial septum, the postoperative PFO diameter was smaller in 5 of the remaining 6 patients. Right-to-left shunting by contrast TEE, however, had newly developed (n = 1) or increased (n = 2) for patients with concomitant valve operation. Despite therapeutic anticoagulation a cerebrovascular event occurred in one patient 4 weeks after attempted PFO closure. The mechanism for persistent shunting was incomplete sealing of septum primum and septum secundum by the suture line (n = 6) or a new iatrogenic defect of the fossa ovalis caused by surgical manipulation (n = 2). In two patients a second TEE after 12 and 41 months revealed enlargement of the PFO diameter. Conclusions Surgical PFO closure can not be regarded as the gold standard for definitive treatment of interatrial shunts. Residual shunting present in a high proportion of patients may partly explain the recurrence of embolic events.