Screening for Coronary Artery Disease in Kidney Transplant Candidates

Abstract

The latest United States Renal Data System Report indicated that there are more than 600,000 patients with end stage renal disease (ESRD) in the United States. Of these, about 90,000 patients are on the waiting list for kidney transplantation. While 38% were listed with inactive status, the remaining 55,371 patients are active candidates, a number three times that of the donor kidney pool. Not surprisingly, the median wait time on the renal transplant wait list continues to rise and has reached about 4.3 years for those newly listed in 2007. The gap between the large candidate pool and the shortage of donor organs poses special challenges with regard to allocation of organs and cardiac risk stratification of patients while on the waiting list. A vast majority of potential renal transplant recipients have ESRD and are on some form of dialysis. Epidemiologic data show that cardiovascular mortality is the leading cause of death among patients with ESRD and by 20-40-fold higher than that of the general population. Similarly, cardiovascular risk is high even for patients with advanced chronic kidney disease (CKD), who are listed for transplantation before starting dialysis. This cardiovascular risk is carried over posttransplant, and the number one reason for renal allograft loss is death with a functioning allograft due to cardiovascular cause claiming 36% of functioning allografts by 10 years after transplantation. Noteworthy, nearly half of the fatalities occurring in the first 30 days post operatively are due to acute myocardial infarctions. The evaluation of this high risk population in preparation for transplantation is different from that advocated by the American College of Cardiology (ACC)/American Heart Association (AHA) Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Non-cardiac Surgery. In this issue of the Journal, Parikh et al review the Scientific Statement From the AHA and the ACC for the Cardiac Disease Evaluation and Management Among Kidney and Liver Transplantation Candidates and highlight the challenges faced during the evaluation of these patients. We will focus our editorial on the kidney transplantation part of the Statement. The Statement advocates for the delay or cancelation of transplantation in patients with active cardiac conditions such as unstable angina, recent myocardial infarction, severe stable angina, decompensated heart failure, significant arrhythmias, and severe valvular disease. The Statement then acknowledges that ‘‘there are no definitive data at this time for or against screening for myocardial ischemia among kidney transplantation candidates who are free of active cardiac conditions.’’ Parikh et al, state the case clearly and effectively against invasive or noninvasive coronary angiography as screening tool for coronary artery disease (CAD) in all transplant candidates. They summarize the diagnostic accuracy of noninvasive stress testing using myocardial perfusion imaging and stress echocardiography (Table 1 in) and Reprint requests: Fadi G. Hage MD, FASH, FACC, Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Lyons Harrison Research Building 314, 1900 University BLVD, Birmingham, AL, 35294, USA; fadihage@uab.edu J Nucl Cardiol 2015;22:297–300. 1071-3581/$34.00 Copyright 2014 American Society of Nuclear Cardiology.