Clinical outcomes of renal transplant recipients undergoing percutaneous coronary intervention
Authors: Zheng W , Dinh D , Bloom J , Brennan A , Ball J , Lefkovits J , Reid C , Chan W , Stub D 
Published: November 2023

Abstract

Background
Cardiovascular disease is the leading cause of mortality among renal transplant (RT) recipients. Despite this, the clinical outcomes of patients with RT undergoing percutaneous coronary intervention (PCI) remain poorly elucidated.

Purpose
This study compared characteristics and outcomes among three groups of patients undergoing PCI: (1) RT recipients, (2) patients receiving dialysis and (3) patients with stage 3 chronic kidney disease (CKD) (estimated glomerular filtration rate 30–59 ml/min/1.73m²) without previous RT.

Methods
Data were analyzed for consecutive patients undergoing PCI enrolled in a large, multicenter Australian registry between 2014 and 2021 stratified into RT (n=226), dialysis (n=992) and CKD (n=15,534) groups. The primary outcome was 30-day major adverse cardiac and cerebrovascular events (MACCE) (composite of mortality, myocardial infarction, stent thrombosis, target vessel revascularization and stroke). Long-term mortality was derived from linkage with the Australian National Death Index. Multivariable logistic and Cox regression were performed to assess the risk of 30-day MACCE and long-term mortality, respectively.

Results
RT recipients were younger compared to dialysis and CKD patients (61±10 vs 68±12 vs 78±8.2 years, p&lt;0.001). The majority of patients were male: 72%, 76% and 61% in RT, dialysis, and CKD groups, respectively (p&lt;0.001). RT patients had fewer comorbidities (diabetes mellitus, peripheral vascular disease and previous cerebrovascular events) than dialysis patients, however more than the CKD group (all p&lt;0.001). Compared to dialysis and CKD groups, RT patients less frequently had severe left ventricular dysfunction (14% and 8.5% vs 6.7%), however more often presented with acute coronary syndrome (52% and 48% vs 58%), especially ST-elevation myocardial infarction (12% and 17% vs 20%) (all p&lt;0.001). RT and CKD patients had lower rates of in-hospital mortality (2.7% and 3.8% vs 6.4%), target vessel revascularization (0.4% and 0.7% vs 1.7%) and 30-day MACCE (4.4% and 6.8% vs 11.6%) compared to the dialysis group (all p&lt;0.001). Three-year survival was similar between RT and CKD groups, however lower in the dialysis group (80% and 83% vs 60%) (p&lt;0.001) (Figure 1). After adjustment, dialysis at baseline was an independent predictor of 30-day MACCE (OR 1.90, 95% CI 1.44–2.50, p&lt;0.001), however RT status was not (0.91, 0.42–1.96, p=0.802). In contrast, both RT status (HR 2.07, 95% CI 1.46–2.95, p&lt;0.001) and dialysis at baseline (1.35, 1.02–1.80, p=0.036) conferred a heightened long-term hazard for mortality (Figure 2).

Conclusions
RT recipients have more favorable clinical outcomes following PCI compared to patients receiving dialysis. Nevertheless, despite having similar short-term outcomes to those with CKD, the hazard of long-term mortality is significantly greater for RT recipients. Close follow-up is warranted in this high-risk population.Figure 1Figure 2