Cardiac Troponin T and Right Ventricular Systolic Pressure Predict Cardiovascular and Mortality Risk in Kidney Transplant Candidates

Abstract

Background: Patients presenting for kidney transplant (KTx) evaluation are subject to high rates of mortality and cardiovascular (CV) events pre- and post-KTx. CV and mortality risk assessment is needed. Methods: We evaluated cardiac troponin T (cTnT) as a predictor of CV events and mortality in a racially diverse cohort with significant CV disease burden presenting for KTx evaluation. Right ventricular systolic pressure (RVSP) was also assessed in predicting these outcomes. The population consisted of 561 patients presenting for KTx evaluation from 2011 to 2013 at Mayo Clinic, Arizona. A cutoff value for cTnT and RVSP that was most associated with CV events or mortality was derived. Multivariate Cox regression analysis was used to assess cTnT, RVSP, traditional, and other risk factors for the outcomes of interest. Results: Mean age was 53.5 ± 13.7 years and the median follow-up after KTx evaluation was 48.0 months. The cohort was 70.6% (n = 392) White, 11.4% (n = 63) Black, 8.5% (n = 47) Native American, and 3.1% (n = 17) Asian. Preexisting CV disease at the time of evaluation was prevalent in 24.4% (n = 137) of patients. During follow-up, 66.3% (n = 372) received a KTx and 21.9% (n = 123) had a composite event (16.8% death, 6.6 % CV events). It was found that 70.7% (n = 87) of events occurred in patients who were not transplanted; 53.5% (n = 300) had an elevated cTnT (≥0.01 ng/mL, median 0.02 ng/mL) and 84.1% (n = 344) of patients with RVSP data had an elevated RVSP (>25 mm Hg). Time to event analysis identified a cTnT ≥0.036 ng/mL and RVSP ≥31 mm Hg to be best predictive of CV events and mortality. Smoking, CV disease, hypoalbuminemia, RVSP, and cTnT independently predicted CV events and mortality. Conclusion: Elevated cTnT and RVSP were independently predictive of CV events and mortality in the cohort. Clinicians should consider the value of RVSP and cTnT as markers of CV risk in KTx evaluation.