Thrombosed Mechanical Aortic Valve Treated with Low-Dose Ultraslow Alteplase Infusion.

Background: Prosthetic valve thrombosis is a rare but serious complication of mechanical valve replacement. Traditionally, prosthetic valve thrombosis has been managed by surgical intervention; however, there is increasing data to support the use of thrombolytics. Methods: We present a case of a 74-year-old female with a history of rheumatic fever and subsequent mechanical aortic valve replacement on warfarin who presented to the emergency department with disequilibrium and chest pain. Results: She was found to have a subtherapeutic international normalized ratio and thrombosed mechanical aortic valve seen on transthoracic echocardiography, transesophageal echocardiography, and fluoroscopy. Conclusions: She was treated with a low-dose ultraslow alteplase infusion of 25 mg of alteplase administered over 25 h. Post-infusion transthoracic echocardiography immediately following infusion and four months later confirmed resolution of thrombosis.