Ischaemic heart disease, cardiac surgery and heart/heart-lung transplantation reviewed from a haematological perspective.
Ischaemic heart disease, one of the major causes of death in the western world, seems to involve a complex interaction of haematological, biochemical, immunological, and physiological processes. Haematologically, the process involves alterations in the haemostatic mechanism as a result of elevations of certain clotting factors, particularly factor VII and fibrinogen, possibly as a result of increased fat consumption and smoking. Platelet hypersensitivity may also be related to immunological damage of the coronary endothelium and elevated fibrinogen levels. Cardiac surgery and heart transplantation remain the most effective methods for treatment of end-stage ischaemic heart disease. Surgical techniques are complex and necessitate the establishment of an extracorporeal blood circulation to bypass the functions of the heart and lungs, enabling the heart to be temporarily paralysed, and allowing surgery to be performed. Extracorporeal oxygenation and circulation of blood, and implantation of ventricular assist devices and artificial hearts, result in exposure of blood to foreign surfaces, leading to activation of the haemostatic mechanism and concomitant haemorrhagic/thrombotic complications. Heart and heart/lung transplantation require long-term regular monitoring of infection and rejection episodes in addition to control of bleeding complications sometimes experienced in the immediate post-operative period. Early identification of lymphoproliferative disorders which may arise as a result of excessive immunosuppression is also important. Implantation of artificial hearts and ventricular assist devices requires much more sophisticated haemostatic monitoring than routine cardiac surgery, in order to control the haemorrhagic/thrombotic complications so often associated with these procedures.
Marshall
D P
DP
Department of Pathology, Papworth Hospital, Cambridge, England, UK.
D001803:Blood Transfusion; D006354:Heart, Artificial; D016041:Heart-Lung Transplantation; D006801:Humans; D009203:Myocardial Infarction / Q000601:surgery*