The Best Weaning after Cardiac Transplantation

Abstract

Since the first human-to-human heart transplant was performed, in 1967, by Christiaan Barnard [1], remarkable progress in this field has been achieved. Heart transplantation nowadays is efficiently performed worldwide with high rates of success: 3175 cases in the year 2000, reported by 321 centers according to reports of International Society for Heart and Lung Transplantation Registry [2]. Improvement of surgical and anesthetic techniques, as well as perioperative care, associated with new immunosuppressive strategies, newer antibiotics planning, improved donor and recipient selection, and graft preservation, have improved results considerably. After transplantation, the average 1-year survival rate is 79.96% and the average 5-year survival rate is about 66%, considering that these survival rates continue to improve. Pre-transplant risk factors are related to the degree of hemodynamic instability of the donor, as well as to the poor general-health conditions of the recipient. An added factor affecting survival is the level of human leukocyte antigen (HLA)-matching between donor and recipient. The literature reports a progressive reduction in the risk of failure after heart transplantation with better HLA matching. Graft dysfunction prevails as a cause of death during the first month after cardiac transplantation. This is because the patient requires more intensive and invasive care with a subsequently higher risk of infection and rejection; an otherwise inefficiently functioning heart compromises others organs, mainly renal and liver function, which limits the doses of immunosuppressive drugs. According to the literature, acute rejection and infection are the predominant causes of death from the first month to one year after heart transplantation (42.21 and 14.30%, respectively) [2]. The most significant problem limiting survival after one year is still chronic rejection (20.46% from 3 to 5 years), which appears as a progressive allograft coronary artery disease (ACAD). This is followed by graft failure (18.56% from 3 to 5 years) and malignancy (15.87% from 3 to 5 years post-transplant) [2]. The immediate management of cardiac transplant recipients is challenging and warrants, beside the basic intensive-care, the administration of immunosuppressive therapies, knowledge of the physiology of the transplanted heart and acute rejection management. Most postoperative management success may be attributed to careful selection of recipient and donor, as well as to protection of the graft against prolonged ischemia. This article aims, based on our institutional experience of 258 cases of adult heart transplant in the last 15 years, to discuss the general aspects of heart transplantation as well as pharmacological and ventilatory support following heart transplantation.