A Large Thrombus in Transit within a Patent Foramen Ovale with Massive Pulmonary Embolism : A Rare Case Report

Reports of thrombi straddling the patent foramen ovale (PFO) are uncommon occurrences. The development of thrombi within the cardiac chambers poses a greater risk of mortality compared to pulmonary embolism (PE) alone and may necessitate a change in treatment strategy [1]. In this case, we describe a rare scenario involving a 53-year-old patient who presented with massive pulmonary embolism. Echocardiography revealed a large thrombus trapped within the patent foramen ovale, protruding into the left heart chambers and causing increased pulmonary artery pressure—a highly unusual and critical condition. Echocardiography emerges as a valuable and safe tool in demonstrating the size, location, and extent of a thrombus, playing a crucial role in the prompt diagnosis and evaluation of treatment options for individuals with a thrombus trapped within a PFO alongside concurrent pulmonary embolism. Our patient received treatment with thrombolysis and anticoagulation, ultimately achieving an uneventful recovery. While the treatment in this case yielded satisfactory results, it may not be universally applicable. Given the rarity of this diagnosis and the limited available data, there is no formally established treatment guideline. Nevertheless, in patients deemed suitable for surgery, studies have indicated improved outcomes with surgical embolectomy compared to anticoagulation alone or thrombolysis. Anticoagulant therapy may represent an acceptable therapeutic alternative, especially for patients with comorbidities at high surgical risk or those with small PFOs. Notably, thrombolysis is associated with the highest mortality, potentially explained by the severity of the patient's initial presentation.