4D TEE-Guided Thrombolysis for Mechanical Mitral Valve Obstruction

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.

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.

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.

In mechanical mitral valve obstruction, 4D TEE can define the dominant mechanism of obstruction, guide selection of thrombolysis vs surgery, and document treatment success.