The role of cardiac evaluation of potential liver transplant recipients
Endocrine System Diseases
Objectives and background Orthotopic liver transplantation is both a difficult and demanding surgical procedure. Because end-stage liver disease affects most organ systems, it is not unexpected that some degree of cardiovascular dysfunction is present in at least some individuals being evaluated for liver transplantation. Thus, all potential liver transplant recipients have undergone a full cardiac evaluation prior to being accepted for possible transplantation. The goal of this study was to review the components of the cardiovascular evaluation utilized at the Oklahoma Transplantation Institute and to determine the overall usefulness of the individual component of the evaluation and the ability of the evaluation process to identify individuals at high risk for a cardiac misadventure during LTx as well as identify candidates deemed unacceptable to risks for LTx because of this heart disease. Between June 25, 1993 and June 30, 1995 a total of 154 consecutive patients with chronic liver disease were evaluated for orthotopic liver transplantation at the Oklahoma Transplantation Institute, Baptist Medical Center of Oklahoma. The primary liver disease of each was established utilizing a battery of a specific serologic and biochemical tests, ultrasonographic and abdominal tomographic findings and a review of all available clinical and liver biopsy data. Hepatic copper and hepatic iron levels were measured in each case utilizing tissue obtained from the removed disease liver. Each liver transplantation (LTx) candidate underwent a full cardiac evaluation consisting of nuclear ventriculography to estimate left ventricular ejection fraction (LVEF) (at rest and during exercise), right ventricular ejection fraction (RVEF), cardiac output, stroke volume and cardiac index; uptake images using thalium and adenosine to identify any foci of transmural cardiac ischemic or fixed defects; and echocardiography to define the dimensions of the various cardiac chambers, wall thicknesses, cardiac contractility and morphology of the cardiac valves. Finally coronary arteriography was performed in 26 patients (16.9%) was strongly suspected. Clinically important coronary artery disease. All of the cardiac evaluations were performed by a single cardiologist. Eight of the 154 potential LTx candidates (5.2%) were determined not to be eligible for liver transplantation because of an inadequate cardiac status. 41 of the remaining 146 patients (22.5%) underwent liver transplantation. The remaining 105 subjects have not been transplanted for a variety of reasons. Eight of the 41 (19.5%) transplanted patients had a clinically advanced cardiac problem recognized prior to LTx. Four of these 8 required a specific cardiac intervention prior to liver transplantation consisting of coronary bypass surgery (n = 1), coronary artery balloon dilatation (n = 2) or pericardiectomy (n = 1). The remaining 4 patients required no pretransplant cardiac intervention and were transplanted. None of these experienced any cardiac complications during the LTx procedure. Only one patient experienced a specific postoperative cardiac complication. This individual experienced an episode of high grade A-V block requiring placement of a cardiac pacing. Based upon this study it can be concluded that coronary artery disease per se is not an absolute contraindication for liver transplantation. With appropriate treatment, liver transplantation can be performed safely in individuals with confounding cardiac disease. Nuclear ventriculography and echocardiography are essential procedures in evaluating potential liver transplant recipients. Coronary arteriography is indicated in selected cases with evidence of cardiac ischemia or infarction based upon the clinical history, examination and other noninvasive cardiac evaluation procedure.