Haemolytic anaemia after mitral valve repair due to recurrent mild to moderate mitral regurgitation

A 52-year-old man underwent mitral valve repair for mitral regurgitation. Four months postoperatively, the patient developed dyspnoea, fatigue and dark urine. He presented to his primary care physician 6months postoperatively, where an evaluation revealed anaemia and mild renal failure. The haemoglobinuria was misdiagnosed as gross haematuria and the patient consequently underwent several unnecessary invasive urological exams. A transthoracic echocardiogram showed a recurrent mitral regurgitation that was considered non-significant, before performing additional laboratory testing and a renewed echocardiogram. The above results showed evidence of haemolysis and a mild to moderate mitral regurgitation, although with a high velocity jet. The patient was diagnosed with haemolytic anaemia that necessitated blood transfusions and a reoperation with a mechanical valve, after which the patient made a full recovery. Importantly, it was mainly the velocity of the jet and not the severity of the mitral regurgitation that caused the mechanical trauma to red blood cells.