4D TEE-Guided Thrombolysis for Mechanical Mitral Valve Obstruction

BACKGROUND: To describe, step by step, how 4-dimensional transesophageal echocardiography (4D TEE) can differentiate thrombus-predominant mechanical mitral valve obstruction from pannus and thereby guide urgent thrombolytic therapy. CASE SUMMARY: A 24-year-old man with a 25-mm mechanical mitral prosthesis presented with NYHA functional class III dyspnea, pulmonary congestion, and a subtherapeutic international normalized ratio of 1.2. Transthoracic echocardiography showed markedly elevated transmitral gradients, and cine-fluoroscopy demonstrated restricted single-leaflet motion. TEE confirmed prosthetic obstruction, whereas 4D TEE provided the decisive mechanistic information by showing a large mobile thrombus with coexisting left ventricular-side pannus, indicating thrombus-predominant obstruction. Streptokinase thrombolysis restored bileaflet mobility and reduced transprosthetic gradients markedly. DISCUSSION: Elevated prosthetic gradients and restricted leaflet motion confirm obstruction but do not reliably distinguish thrombus from pannus. Mixed pathology may be missed if multimodality imaging is not performed. TAKE-HOME MESSAGE: In mechanical mitral valve obstruction, 4D TEE can define the dominant mechanism of obstruction, guide selection of thrombolysis vs surgery, and document treatment success.