Multimodality Diagnostics and Endovascular Large-Bore Aspiration Thrombectomy of the Clot-in-Transit.

Clot-in-transit (CIT) is a free-floating thrombus in the right heart and can enter pulmonary circulation at any moment. Possible treatments include anticoagulation, systemic thrombolysis, surgical embolectomy, and endovascular catheter-based therapies. The optimal treatment is still undetermined, heavily relying on clinical judgment and multidisciplinary team discussion. We report a case of a 70-year-old woman presenting with tachydyspnoea following recent abdominal surgery, who was diagnosed with massive bilateral pulmonary embolism (PE) complicated by a clot-in-transit. Point-of-care ultrasonography revealed a large mobile thrombus in the right atrium with severe right ventricular dysfunction. Due to haemodynamic instability and a contraindication for systemic thrombolysis, mechanical thrombectomy was performed. A large thrombotic burden was aspirated from the right heart and pulmonary arteries, resulting in haemodynamic stabilization and recovery of right ventricular function. The patient remained stable throughout hospitalization and was discharged on oral anticoagulation therapy with complete recovery on follow-up. This case highlights several points. Firstly, CIT is a rare finding but should be considered in patients with massive pulmonary embolism and shock. Furthermore, POCUS is essential for diagnosing CIT. Finally, mechanical thrombectomy is a valuable therapeutic option in high-risk PE patients with contraindications to systemic thrombolysis and haemodynamic instability. Further studies are needed to establish adequate guidelines for the optimal management of CIT patients.