الفهرس 
PATHOPHYSIOLOGY OF THE TRANSPLANTED HEARTOnly 14 pages are availabe for public view
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Abstract
There are some patho-physiological changes following heart transplantation, the heart is denervated and the baseline heart rate is increased due to loss of vagal input, but the maximal working capacity of the transplanted heart is limited by the reduced heart rate during exercise and anaerobic metabolism.
Rejection and cardiac allograft vasculopathy (CAV) are the most serious problem, but infection is the most common. Other complications include silent ischemia, hypertension and diabetes which worsen the outcome, in addition increased incidence of malignancies due to immunosuppreant therapy.
Immunosuppressant therapy regimens passes in 2 stages, induction and maintenance therapies, anti-lymphocyte (polyclonal and monoclonal) and interleukin-2 receptor antagonist are the immunosuppressive drugs that are commenly used in induction therapy. While a triple combination of calcineurin inhibitor, an antiproliferative agent and steroid are considered as maintenance therapy. It should be started immediately postoperative for life and should not be discontinued even in period of severe infections.
Acute rejection therapy is usually treated with a course of oral or intravenous high-dose steroid therapy for 3 to5 days.
Immunosuppressive drugs have various side effects and interactions with anethetic drugs that should be thoroughly studied for safe delivery of anethesia.
Preoperative management includes evaluation of all organs with especial emphasis on the transplanted heart.it is composed of careful history taking, physical examination and good investigations.
Infection prophylaxis is important in such patients as they are on immunosuppressant therapy. Invasive monitoring should be limited.
Choice of anesthesia should be done according to every case, as there is no fixed protocol for all cases. Emphasizing on the control of the preload and fluid balance of the patient because, those patients are preload dependent.
Previous transplantation per se does not necessitate postoperative ICU admission. Pain control is very important using epidural analgesia or parenteral opioids.
Pregnancies in heart transplant recipients are associated with increases in spontaneous abortion rates, hypertension in pregnancy and pre-eclampsia. The delivered infants have an increased incidence of complications, including developmental delay, which is not surprising given the increased incidence of prematurity and low birthweight.