Synergistic anticoagulation and transoesophageal echocardiographic surveillance for persistent left atrial appendage thrombus
A 49 year old woman was referred for consideration of percutaneous mitral valve commissurotomy caused by symptoms of worsening exertional breathlessness. She had a long history of rheumatic mitral stenosis complicated 10 years previously by a left parietal lobe embolic stroke and the onset of permanent atrial fibrillation. She was anticoagulated with warfarin following this but was left with some residual disability.
Transoesophageal echocardiography (TOE) demonstrated severe mitral stenosis with a large thrombus visible in the left atrial appendage (below left). Anticoagulation control before this had been good (international normalised ratio (INR) 2.5). The patient was offered mitral valve surgery but declined. She was initially treated with clopidogrel 75 mg daily and the target INR increased to 3.5. Repeat TOE at both one and two months demonstrated persistence of the thrombus. Aspirin 75 mg was added synergistically to her anticoagulation therapy and serial TOE scanning over the subsequent six months demonstrated a progressive reduction in size (below right).
Although resolution of large left atrial appendage thrombi has been previously reported, this case demonstrates the need to assess the response of large thrombi to anticoagulation by repeated TOE. This case also displays the potential for synergistic antiplatelet treatment in the management of persistent left appendage thrombi.