AL cardiac amyloidosis and arterial thromboembolic events

OBJECTIVE: To study the prevalence and characteristics of arterial thromboembolic events (ATEE) in the course of AL amyloidosis. METHODS: We report the case of a non-anticoagulated patient with AL amyloidosis restrictive cardiomyopathy who developed acute lower limb ischaemia. We then prospectively determined the prevalence of ATEE in all patients with AL amyloidosis who were evaluated in our institution for autologous peripheral stem cell transplantation. RESULTS: Nine out of 15 non-anticoagulated patients (60%) developed ATEE: ischaemic stroke (3), transient cerebral ischaemic attack (2), multiple peripheral arterial emboli (1), bilateral iliac artery thrombosis (1), bilateral optic nerve ischaemia (1), and mesenteric ischaemia (1). Haemodynamic stasis seemed to play a leading role in the pathophysiology of ATEE, in that all patients were on sinus rhythm and only one had a thrombus on echocardiography. We identified possible contributing factors to ATEE occurrence: concomitant treatments with oestroprogestogen regimen, thalidomide, granulocyte-macrophage colony-stimulating factor (GM-CSF) and extracellular volume disturbances related to the cytapheresis procedure. CONCLUSION: We report on an unusual frequency of ATEE among patients with AL cardiac amyloidosis. Despite its theoretical risks, anticoagulation should be discussed for patients with amyloid cardiomyopathy.