Obstructive dysfunction of a mechanical mitral prosthesis due to pannus and thrombus: a case report

Mechanical prosthetic valve dysfunction is a rare but highly serious complication, particularly in the mitral position. We present the case of a 40-year-old female patient with a history of rheumatic heart disease, mechanical mitral valve replacement, and suboptimal anticoagulation, who was admitted with severe dyspnea, acute pulmonary edema, and a focal neurological deficit consistent with ischemic stroke. Transthoracic echocardiography revealed increased transprosthetic gradients and restricted valve mobility, while transesophageal echocardiography confirmed a mass consistent with a thrombus associated with pannus, causing obstructive dysfunction of the mitral prosthesis. Despite intensive care unit management, ventilatory support, and the medical treatment initiated, the patient’s clinical course was unfavorable, characterized by refractory acute pulmonary edema and progressive neurological deterioration; she passed away during hospitalization. This case highlights the importance of timely diagnosis and the differentiation between thrombosis.