A Case Series of Obstructive Prosthetic Mitral Valve Thrombosis, Successfully Treated with Low-Dose, Slow Infusion...

Prosthetic valve thrombosis (PVT) is a rare but serious complication of the prosthetic heart valve. Although recent guidelines generally recommend surgical treatment as the main option for patients with obstructive left-sided PVT, thrombolytic therapy (TT) may offer another attractive approach. There is also no consensus on the type, dose and route of administration of thrombolytic agents. The present study included a small series of patients with low-dose, slow infusion tissue-type plasminogen activator (tPA) to treat PVT in the mitral position.

Eight consecutive episodes of mitral PVT (one woman was pregnant) in seven patients were treated with low-dose (25 mg), slow infusion (within 6 h) tPA, if needed, with repeat sessions of TT (with the same protocol up to a total dose of 150 mg) until a satisfactory result was achieved.

The cause of PVT was inadequate anticoagulation with warfarin or low-molecular-weight heparin in all patients on admission. A complete resolution of hemodynamic instability and echocardiographic abnormalities was observed in all cases, without mortality. In addition, there were no thromboembolic and major hemorrhagic complications in the case series.

These findings suggest that low-dose, slow infusion tPA may be applicable to bileaflet mitral PVT in relatively stable patients, and may represent a therapeutic option to surgery.