Hematologic changes in cyanotic congenital heart disease: a review

Several hematologic changes occur in children and adults with chronic cyanosis – some adaptive, some maladaptive. Changes in blood viscosity, iron metabolism, coagulation profile change, and thromboembolic risk all occur with secondary erythrocytosis. It is important that medical professionals understand these changes and their clinical significance as chronic cyanosis has multi systemic consequences. This article will focus on a review of pathophysiology and clinical practice guidelines as they pertain to hyperviscosity, iron deficiency, hyperuricemia, bleeding tendencies, thromboembolism, and central nervous system complications.