SAMIKSHAHEARTCARE 57698d5b9ec66b0b6cfb5b6b False 536 1
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POPULAR CARDIOLOGIST IN KATTIGENAHALLI, BANGALORE Cyanotic congenital heart disease Some of the more common cyanotic lesions are discussed below. There are, however, a number of problems common to patients with cyanotic heart disease. 1 Erythrocytosis. Chronic cyanosis causes an increase in red cell numbers as a way of increasing oxygen carrying capacity. The platelet count is sometimes reduced and the white cell count normal. The increased blood viscosity associated with the high red cell mass causes a slight increase in the risk of stroke.37 Most patients have a stable elevated haemoglobin level, but venesection is recommended if this is greater than 20 g/dL and the haematocrit is greater than 65%. Levels as high as this can be associated with the hyperviscosity syndrome: headache, fatigue and difficulty concentrating. Recurrent venesection can cause iron depletion and the production of microcytic red cells, which are stiffer than normal cells and so increase viscosity further. 2 Bleeding. Reduced platelet numbers, abnormal platelet function and clotting factor deficiencies mean these patients have an increased risk of haemorrhage. The most dangerous problem is pulmonary haemorrhage but bleeding from the gums and menorrhagia are more common. The use of anticoagulation must be restricted to those with a strong indication for treatment. 3 Gallstones. Chronic cyanosis and increased haem turnover are associated with an increased incidence of pigment gallstones. 4 Renal dysfunction and gout. Congestion of the renal glomeruli is associated with a reduced glomerular filtration rate and proteinuria. This and the increased turnover of red cells lead to urate accumulation and gout. 5 Pulmonary hypertension. Lesions associated with increased flow through the pulmonary circulation (e.g. a large atrial septal defect) can lead to a reactive rise in pulmonary arterial resistance. This is more likely to occur if the left to right shunt is large. Eventually these pulmonary vascular changes become irreversible, pulmonary pressures equal or exceed systemic pressures, and central cyanosis occurs because the intra-cardiac shunt reverses (Eisenmenger’s syndrome). Flow is now from right to left. There is then no benefit in attempting to correct the underlying cardiac abnormality. Earlier and more successful treatment of children with congenital heart disease has reduced the number of patients with this inexorable disease. Careful management of these conditions can nevertheless improve patients’ symptoms and survival. Reasonable exercise tolerance is usually maintained into adult life for most patients but progressive deterioration then occurs. Haemorrhagic complications, especially haemoptysis, are common. Thrombotic stroke, cerebral abscess and pulmonary infarction can also occur.
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