128 Intravascular Haemolysis – A Rare Complication of the MitraClip

Abstract

In high risk surgical candidates, percutaneous edge-to-edge repair using the MitraClip system is a well-established alternative to treat mitral regurgitation (MR), with over 80,000 cases performed since its conception. We report a case of transfusion-dependent intravascular haemolysis related to the MitraClip, a rare and seldomly reported complication. An 84-year-old lady with severe MR secondary to posterior leaflet prolapse on a background of hypertension, hypercholesterolaemia, osteoporosis and glaucoma underwent successful MitraClip repair with 2 clips deployed, resulting in MR reduction from severe to mild-to-moderate on echocardiogram. She was discharged home 48 hours later with no immediate complications. Macrocytic anaemia was noted at 1-month post procedure with replete iron, B12 and folate levels, and further assessment at 4-months revealed undetectable haptoglobin levels with positive urine haemosiderin. Immune-mediated haemolysis screens were negative. Peripheral blood film demonstrated polychromasia and target cells, with occasional bite cells and red cell fragments. Increased erythropoiesis was noted in a hypercellular bone marrow biopsy. The laboratory work-up and the temporal association of the intravascular haemolysis with MitraClip confirmed the diagnosis. The patient has been managed effectively with monthly red blood cell transfusions and folate supplementation. She declined further intervention for her mitral valve. To the best of the authors’ knowledge, this is only the second case of MitraClip-related intravascular haemolysis reported worldwide, and the first to require regular transfusions. Interestingly, red cell fragmentation was not prominent on blood film, in contrast to other presentations of mechanical haemolysis. This rare complication should be considered in persistently anaemic patients post-MitraClip.