Who let the clot out?: a case of mitral annulus thrombosis resolved by direct anticoagulants

Background: During the last years DOACs have been found to be at least as safe and effective as vitamin K antagonists for stroke prevention in atrial fibrillation (AF) and management of venous thromboembolism with real-world data showing similar outcomes. Mitral annulus calcification (MAC) with caseous necrosis (CN) has been associated with an increase of stroke. In these patients AF and embolic thrombus by MAC may be another potential causes. Case: A 75 years old men, sportsman (ski mountaineering), with a known coronary artery disease (CAD) previously treated with an elective, uncomplicated PCI 2 years before and a normal systolic function, was admitted to the hospital referring dizziness, nausea, confusion, paresthesias and he-adache in the last 2 hours. No history of AF was reported nor it was detected during hospitalisa-tion. Radiological investigations showed signs of an embolic stroke involving temporal, hippocam-pal, occipital areas and the patient experienced a full clinical recovery after 6 days. Transthoracic and transesophageal echocardiograms (TTE, TOE) were performed showing a MAC with a 1.5 cm hyperechogenic mass and a 1.4 cm mobile thrombus attached to the base of the posterior mitral valve (MV) leaflet without functional MV impairment. DOAC therapy (Apixaban 5mg b.i.d.) was added on top of the ongoing antiplatelet therapy with aspirin. The patients recovered from neuro-logical symptoms after 6 days and 4 weeks after discharge the he was referred to undergo cardiac surgery on the MV. TTE and TOE were repeated the day before surgery confirming the presence of MAC with CN but the thrombus was not visualised. A total body CT-scan showed no signs of fur-ther embolization and he was discharged asymptomatic with the same therapy and a 3 months follow-up echocardiography was planned. Discussion: The use of DOACs in the context of ventricular or valvular thrombosis is described in some case reports but is actually generally considered an “off-label” strategy. In our case a 3-week treatment with Apixaban was able to completely resolve a large (>1cm) cardioembolic thrombus attached to a calcific MV annulus, preventing a high risk cardiac surgery with no clinical or radiolo-gical signs of further embolization. Conclusions: We present a case of a cardioembolic thrombus attached to a calcific MV completely resolved with DOAC. Even if there is no strong evidence for extended clinical use of DOACs in this context, they can be considered in specific patients.