O027 Less is more: extensive cardiac investigations add little value in waitlisting patients for kidney transplantation

Introduction The utility and reliability of extensive cardiac investigations to aid waitlisting for kidney transplantation has been debated. This study assessed the prognostic power of coronary artery calcium scoring (CACS) using computed tomography coronary angiogram (CTCA) and myocardial perfusion scintigraphy (MPS) in predicting major adverse cardiac events (MACE). Methods We conducted a retrospective study of all ESRD patients considered for kidney transplantation and referred for MPS and/or CTCA for CACS between October 2012 to March 2014 and assessed MACE occurrences (heart failure, cardiac arrest, myocardial infarction, angina, CVA, PVD and transient ischaemic attack) over a 9-year follow-up period. Results Among 131 patients in our study, 91.6% had a MPS (76.7% Negative MPS result, 23.3% Positive MPS) and 92.4% had a CTCA (75.2% CACS <400 (Low Score), 24.8% CACS>400 (High Score)). Sensitivity, specificity, positive and negative predictive values were poor for CTCA (38.8%, 84.7%, 63.3%, 67.0%) and MPS (34.8%, 82.4%, 55.2%, 67.0%). There was no statistical significance in MACE when stratified by CACS and MPS in transplanted patients (log-rank p=0.155); statistical significance observed when stratified by transplant status in all patients (p=<0.0001). No statistical difference in MACE observed when stratified by MPS (p=0.749) or CACS (p=0.706) in non-transplanted patients. Conclusion This challenges the value of extensive cardiac assessments (MPS, CTCA) in predicting MACE. Candidates conventionally considered low-risk by these methods had similar risk of MACE when transplanted against higher-risk groups. Transplantation confers an advantage in MACE-free years. Such tests are best used for risk stratification and counselling for shared decision-making. Take-home message Extensive cardiac investigations such as MPS and CTCA are poor predictors of MACE in end-stage renal disease patients. These tests should not be used as key determinants in waitlisting patients for kidney transplantation.