Introduction

Pulmonary embolism (PE) with thrombus entrapment in a patent foramen ovale (PFO) is rare, with an incidence rate of 3.8%, but constitutes a medical emergency due to its associated risk for systemic embolization [1]. The mortality rate from this paradoxical embolization is approximately 18%, and roughly two-thirds of these deaths occur within 24 hours. PE can elevate right-sided atrial pressure and can precipitate entrapment by augmenting right-to-left shunting through the pre-existing PFO. Stroke risk certainly is of paramount concern from this paradoxical embolism in this situation, and requires emergent intervention [1,2]. Therefore, clinical management must take into account previous risk factors of cerebrovascular events while simultaneously providing emergent interventions and careful consideration of managing stroke should it occur. Risk assessment must also be considered with anticoagulation, systemic thrombolysis, and catheter-directed intervention, as these can theoretically be associated with fragmentation of the clot, thereby further increasing the risk of pulmonary and systemic embolization [1,3].

Current guidelines support the use of advanced therapies over anticoagulation alone, with evidence of clot-in-transit [4]. However, this management mainly focuses on the travel of the clot on the pulmonary side, and there is no clear guideline on management principles when paradoxical embolization is imminent. With the emergent nature of the presentation of a clot entrapped in a PFO, plans for intervention, including surgical or catheter-directed thrombectomy (CDT) with PFO closure, must be determined. With the rarity of occurrence and, as mentioned, a dearth of research evidence, no guidelines currently exist identifying a superior method, highlighting the importance of interdisciplinary and patient-centered approaches in care management. Overall, emergent surgical intervention has been shown to be safe and effective while allowing for simultaneous PFO closure, thereby reducing the risk of paradoxical embolism [1,2]. CDT, although more popular in the management of massive and submassive PE, has not been studied in the setting of patients with PE and PFO [2].

We present here a case where there is a connected intracardiac, inter-atrial septal clot extending into the pulmonary arteries. While managing this patient, we acknowledged the legitimate risk of breaking off the clot as it straddled across the atria with the use of conventional catheter-directed embolectomy and systemic thrombolysis. In this instance, surgical embolectomy was employed as it was deemed to be the safest option.