Pulmonary Embolism and Prominent Eustachian Valve

Introduction: We report a rare case of massive PE with bilateral DVT and a right atrial clot in transit linked to a prominent Eustachian valve (EV), treated successfully with thrombectomy and anticoagulation.


Description: A 68-year-old male with Lewy body dementia, OSA, and type 2 diabetes presented with dyspnea and hypoxic respiratory failure. He was febrile, tachycardic, hypoxic (SpO₂ 82% RA), and normotensive. Labs showed elevated troponin, lactate, and normal BNP, ABG with hypoxemia and respiratory alkalosis. ECG showed sinus tachycardia. CT angiogram demonstrated bilateral PE with RV dilation and septal bowing. Lower extremity duplex showed bilateral DVT. Given the intermediate-high risk PE classification, the patient underwent percutaneous pulmonary artery thrombectomy using a 24Fr Inari FlowTriever aspiration device (Inari Medical, Irvine, California), with simultaneous placement of an inferior vena cava filter. Post-procedure TTE revealed moderate RV dilation and a 3.2×1.4 cm RA mass concerning for clot in transit. RA thrombectomy was performed, and follow-up TTE later showed a prominent Eustachian valve. He was started on apixaban and discharged from the ICU on 2L O₂.


Discussion: The EV, a fetal remnant in the right atrium, can serve as a nidus for thrombus formation in adults. Schuchlenz et al. reported prominent EVs in 57% of patients undergoing transesophageal echocardiography. Rarely, EV-associated thrombi embolize to the pulmonary arteries, presenting as PE or right atrial "clot in transit." Maddury et al. described recurrent PE from an EV thrombus requiring surgical thrombectomy. Thrombus in transit is seen in about 4% of PE cases and has a mortality rate up to 20%. Management includes anticoagulation, thrombolysis, catheter-based therapy (CDT), and surgery. Zhang et al. found mortality rates of 50% with anticoagulation alone vs. 8% with catheter-based therapies. In another study, Singh et al. found CDT linked to longer ICU stays and similar bleeding risk. In our case, PE was likely multifactorial, from bilateral DVT and EV-associated thrombus. Mechanical thrombectomy (MT) was favored over thrombolysis due to bleeding risk and dementia. This case supports the efficacy of MT for complex PE with EV involvement, with anticoagulation in the post-procedure setting.