Wood John C
Division of Pediatric Cardiology, Children's Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, CA 90027, USA.
Blood Rev. 2008 Dec;22 Suppl 2(Suppl 2):S14-21. doi: 10.1016/S0268-960X(08)70004-3.
Iron overload occurs in patients who require regular blood transfusions to correct genetic and acquired anaemias, such as beta-thalassaemia major, sickle cell disease, and myelodysplastic syndromes. Although iron overload causes damage in many organs, accumulation of cardiac iron is a leading cause of death in transfused patients with beta-thalassaemia major. The symptoms of cardiac iron overload will occur long after the first cardiac iron accumulation, at a point when treatment is more complex than primary prevention would have been. Direct measurement of cardiac iron using T2* magnetic resonance imaging, rather than indirect methods such as measuring serum ferritin levels or liver iron concentration have contributed to earlier recognition of myocardial iron loading and prevention of cardiac toxicity. Cardiac siderosis occurs in all transfusional anaemias, but the relative risk depends upon the underlying disease state, transfusional load, and chelation history. All three available iron chelators can be used to remove cardiac iron, but each has unique physical properties that influence their cardiac efficacy. More prospective trials are needed to assess the effects of single-agent or combination iron chelation therapy on the levels of cardiac iron and cardiac function. Ultimately, iron chelation therapies should be tailored to meet individual patient needs and lifestyle demands.
铁过载发生在需要定期输血以纠正遗传性和获得性贫血的患者中,如重型β地中海贫血、镰状细胞病和骨髓增生异常综合征。尽管铁过载会对许多器官造成损害,但心脏铁蓄积是重型β地中海贫血输血患者的主要死因。心脏铁过载的症状会在首次心脏铁蓄积很久之后出现,此时治疗比一级预防更为复杂。使用T2*磁共振成像直接测量心脏铁,而不是采用测量血清铁蛋白水平或肝脏铁浓度等间接方法,有助于更早地识别心肌铁负荷并预防心脏毒性。心脏铁沉着症发生在所有输血性贫血中,但相对风险取决于潜在疾病状态、输血负荷和螯合治疗史。所有三种可用的铁螯合剂都可用于清除心脏铁,但每种都有独特的物理特性,会影响其对心脏的疗效。需要更多前瞻性试验来评估单药或联合铁螯合疗法对心脏铁水平和心脏功能的影响。最终,铁螯合疗法应根据个体患者的需求和生活方式要求进行调整。