Bioprosthetic Mitral Valve Leaflet Thrombosis, Novel Oral Anticoagulants a Potential Solution for a Sticky Problem

Abstract

A 52-year-old female presented with NYHA class III dyspnoea on a background of a previous bioprosthetic mitral valve replacement. This was inserted five years previously for severe mitral regurgitation secondary to anthracycline cardiomyopathy. The patient had declined a mechanical valve prosthesis. Transoesophageal echocardiography demonstrated restricted leaflet motion, and confirmed severe stenosis of the bioprosthetic mitral valve with a mean gradient of 12 mmHg across the valve. Coronary angiogram did not reveal significant coronary disease and after heart team discussion the patient was referred for a re-do mechanical mitral valve replacement. Whilst awaiting surgery apixaban was prescribed for a deep vein thrombosis and co-existent paroxysmal atrial fibrillation. A repeat transoesophageal echocardiogram performed on table pre-sternotomy two months later revealed normal bioprosthetic valve function with appropriate leaflet excursion and a mean gradient of 3 mmHg across the valve. The patient's symptoms had improved during the anticoagulation period. Bioprosthetic valve leaflet thrombosis (BVLT) has been reported post transcatheter and surgical bioprosthetic aortic valve replacements. This clinical vignette highlights the importance of recognising BVLT in the months and years post implantation. The case also demonstrates a potential role for novel oral anticoagulants in treating this condition. Future studies are required to determine risk factors for BVLT and optimal treatment methods.