The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation
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J. Heart Lung Transplant. · Nov 1996
Comparative StudyExercise capacity of heart transplant recipients: the importance of chronotropic incompetence.
Maximal exercise capacity is limited in patients after heart transplantation. The extent to which chronotropic incompetence contributes to this intolerance has not been well defined. ⋯ The reduction in peak oxygen consumption, particularly during the first 2 years, appears to be related in part to chronotropic incompetence. Late after transplantation the heart rate response to exercise is greater and the decline in heart rate after exercise faster, suggesting possible autonomic reinnervation in some patients. Chronotropic incompetence may be an inadequate explanation of oxygen uptake impairment seen late after transplantation, when other factors such as myocardial dysfunction and intrinsic skeletal muscle abnormalities are of increasing importance.
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J. Heart Lung Transplant. · Nov 1996
Comparative StudyEnhancement of cytomegalovirus infection and acute rejection after allogeneic lung transplantation in the rat: virus-induced expression of major histocompatibility complex class II antigens.
Cytomegalovirus infection is considered a major complication after lung and heart-lung transplantation because it can trigger acute and chronic rejection. The potential mechanisms of lung transplant rejection induced by viral infection include the upregulation of expression of major histocompatibility complex antigens. To address this question, a model of rat cytomegalovirus infection and acute lung transplant rejection was established. ⋯ Our results indicate that cytomegalovirus induces and enhances the expression of major histocompatibility complex class II antigens on endothelial cells, pneumocytes and leukocytes. Upregulation by cytomegalovirus infection may trigger or promote acute rejection by alloantigenic T-lymphocyte stimulation after lung transplantation. By this mechanism it may strongly influence the long-term course of lung transplant rejection.