Intracardiac thrombi in antiphospholipid syndrome (APS)

Abstract

APS is a multisystem autoimmune disease associated with recurrent arterial and venous thrombosis and pregnancy loss. Cardiac manifestations include valve abnormalities, coronary artery disease, myocardial dysfunction, pulmonary hypertension and intracardiac thrombi. A potentially life-threating but treatable manifestation of APS is intracardiac thrombus (IT). Thrombus formation can cause embolic pulmonary and systemic events and it remains uncertain about the mechanism of its formation. IT can occur in all cardiac chambers and needs to be differentiated from intracardiac myxoma. Echocardiography and cardiac MRI are the best tools for IT diagnosis. We present 2 cases of IT in APS. 

CASE 1: A 39 years old woman who had a medical history of systemic lupus erythematosus diagnosed 3 years previously, she developed severe headache with right hemiparesis that fully recovered in 4 hours. Brain MRI showed left frontal diffusion restriction focus and carotid ultrasound without atherosclerotic lesions.  Doppler Transthoracic echocardiography showed a mobile mass 22x 10 mm attached to the left atrial wall. (Image 1) Cardiac MRI showed 2 intracardiac thrombi attached by pedicle to posterior free wall of atrium (Image 2). A laboratory investigation revealed; Lupus anticoagulant (LA) positive, Anticardiolipin Ig G (ACL Ig G), Ig M (ACL Ig M) (-), Anti BGPI Ig G e IG M (-). She started on enoxaparin (therapeutic dose) and warfarin with a target 2.5-3. She stayed for 5 days in the hospital with improvement of her symptoms and repeated ECHO showed fully resolution of IT 6 months later.  

CASE 2: A 36 years old man was referred for cardiac and rheumatology evaluation to our hospital. He had a medical history of primary APS diagnosed 8 years ago. He had 3 episodes of DVT and pulmonary emboli (PE)with triple positivity of antiphospholipid antibodies (LA, ACL Ig G and Anti-B2GPI Ig G) without treatment. He also had a history of overweight, smoking and cocaine consumption in the past.  Four months before, he developed acute dyspnea and he was diagnosed of PE and he received thrombolytic therapy and he was discharged with oral anticoagulation.  Two months later, he developed severe chest pain while he was at rest. ECG showed negative T wave from V1 to V3, and his cardiac enzymes were within normal limits. He received nitrates, statins. Low molecular heparin, aspirin and statins. He was discharge with oral anticoagulation with warfarin plus aspirin with INR of 3. Transthoracic echocardiography showed left ventricular dilatation with regional wall motion abnormalities and intracardiac thrombi of 33x22x39mm that it also was seen in cardiac MRI. (Image 3) Warfarin and aspirin treatment was prescribed. 

IT has rarely been reported in APS patients. This cardiac manifestation should be considered because early diagnosis and proper management with anticoagulant therapy are essential to prevent mortality. 

Keywords:  Intracardiac thrombi; antiphospholipid syndrome