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.
DISCUSSION: We 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.