A case report of extramedullary haematopoiesis within left ventricle myocardium and apical thrombus in acute heart failure: diagnosis, treatment, and long-term outcome

Abstract

Background Extramedullary haematopoiesis (EMH) within myocardium is a rare phenomenon, and its occurrence in left ventricle myocardium or apical thrombus of a young female has never been reported.Case summary A 23-year-old active female with progressive worsening of dyspnoea. A transthoracic echocardiogram demonstrated a left ventricular ejection fraction of 10–15% and apical thrombus. Bilateral upper extremity Doppler showed deep venous thrombus in the left arm and superficial vein thrombus in both arms. She had reduced activity of antithrombin III, deficiency of protein C and S. Computed tomography of the head showed right thalamic infarct. Having failed optimal medical therapy, rapidly worsening of symptoms (New York Heart Association Class IV and clinical Class C) and cardiogenic shock, she underwent HeartWare® left ventricular assist device (LVAD) placement as a bridge to heart transplant. Intraoperative apical thrombus was carefully extracted while maintaining adequate anticoagulation with heparin infusion. Pathology report of the excised apical myocardium and thrombus demonstrated haematopoietic cells. Twenty-six months since LVAD implantation, she remains active and Status 7 on transplant list (due to body mass index) without any further episodes of thromboembolic events.DiscussionWe report an unprecedented case of an active young female with EMH within left ventricular myocardium and apical thrombus. Although redirected differentiation and embolic haematopoietic cells seem to explain this phenomenon, the exact pathophysiology remains unknown. Despite having pre-existing apical thrombus and acute deep vein thrombus, the key towards success was meticulous extraction of apical thrombus while preserving inherent trabecular architecture and adequate anticoagulation.