Coronary artery disease burden in kidney transplant candidates: Risk factors, outcomes, and impact on transplant eligibility.

Background: Chronic kidney disease (CKD) independently predicts cardiovascular outcomes. However, the quantification of coronary artery disease (CAD) burden in patients undergoing renal replacement therapy (RRT), its risk factors, its relationship with transplant eligibility, and long-term prognosis still need to be fully established.

Objectives: This study aimed to identify the risk factors associated with a high CAD burden and evaluate its impact on renal transplant eligibility and long-term outcomes in CKD patients undergoing RRT.

Methods: This is a retrospective cohort study of CKD patients undergoing RRT and coronary angiography for kidney transplant stratification. CAD burden was evaluated using the SYNTAX Score (SS) and categorized into four groups: non-obstructive CAD, low, intermediate, and high CAD burden. The primary endpoint was Major Adverse Cardiac and Cerebrovascular Events (MACCE), which comprised all-cause mortality, myocardial infarction, stroke, and coronary revascularization.

Results: Of the 1226 participants, 466 (38.0 %) had no CAD, 256 (20.9 %) had low, 257 (21.0 %) had intermediate, and 247 (20.1 %) had high CAD burden. Male sex (p < 0.001), diabetes (p < 0.01), peripheral artery disease (p < 0.001), and positive myocardial perfusion scintigraphy (p < 0.001) were the main predictors of high atherosclerotic burden. After 985 days, MACCE occurred in 26.6 % of the non-obstructive CAD group and 41.6 %, 43.9 %, and 59.7 % of the low, intermediate, and high CAD burden groups, respectively (p < 0.01). Age (p < 0.01), Left Ventricular Ejection Fraction (p < 0.01), and SS >7 (p < 0.01) were predictors of MACCE. Renal transplantation during follow-up reduced the incidence of MACCE (p < 0.01). However, the likelihood of transplantation decreased as CAD burden increased: 19.74 % in the non-obstructive CAD group and 16.80 %, 14.40 %, and 5.67 % in the low, intermediate, and high CAD groups, respectively (p < 0.01).

Conclusions: Our results revealed a rising risk of major outcomes with increasing CAD burden. Kidney transplantation mitigated MACCE but was limited by CAD severity.