Background and Disease Burden
Chronic kidney disease (CKD) is a prevalent condition globally, affecting approximately 10-15% of the adult population. It is well recognized as a significant risk factor for cardiovascular disease (CVD), which remains the leading cause of morbidity and mortality in CKD patients. Percutaneous coronary intervention (PCI) is frequently performed in these individuals to manage ischemic heart disease. However, the presence of CKD complicates the clinical course, partly due to heightened risk of atherosclerosis, comorbidities, and procedural challenges. Reduced left ventricular ejection fraction (LVEF), indicative of impaired myocardial contractility and heart failure, is established as a predictor of poor outcomes after PCI in the general population. Yet, the influence of reduced LVEF specifically in the CKD cohort undergoing PCI has been less clearly defined. Understanding this relationship is crucial for optimizing risk stratification, management, and improving prognostication in this high-risk group.
Study Design
This retrospective cohort study analyzed data from 12,353 patients who underwent PCI at a tertiary-care center between 2012 and 2023. Patients were categorized by presence or absence of CKD, defined as estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m2. Within each group, patients were further stratified based on left ventricular function, with reduced LVEF defined as less than 50%. The primary outcome was the incidence of major adverse cardiovascular events (MACE) at one year post-PCI. MACE was a composite endpoint including all-cause mortality, myocardial infarction (MI), or target vessel revascularization. Secondary endpoints such as individual components of MACE and subgroup interactions between LVEF and CKD were also examined.
Key Findings
Of the total cohort, 3,199 patients (25.9%) had CKD, and among these, 751 (23.5%) exhibited reduced LVEF. For CKD patients, mean LVEF was 36.7% ± 8.5% in the reduced LVEF subgroup compared to 59.6% ± 4.9% in those with normal function, statistically significant with P < .001. Comorbidities and atherosclerotic burden were greater in patients with reduced LVEF, consistent with a sicker cardiovascular phenotype.
Interestingly, within the CKD population, the composite MACE endpoint did not differ significantly between reduced and normal LVEF groups (hazard ratio [HR] 1.18; 95% confidence interval [CI] 0.90–1.54; P = .23). However, reduced LVEF was associated with significantly higher rates of all-cause mortality (HR 1.85; 95% CI 1.10–3.10; P < .05) and myocardial infarction (HR 1.78; 95% CI 1.07–2.98; P < .05). This suggests that while overall cardiovascular event rates were similar, the risk profile for death and MI was elevated in those with depressed ventricular function.
In non-CKD patients, reduced LVEF correlated with increased risk of both MACE and all-cause death, emphasizing the prognostic importance of left ventricular function irrespective of kidney status. Notably, no significant statistical interaction was found between LVEF and CKD presence on outcomes, indicating that the impact of reduced LVEF does not differ substantially between these clinical groups.
Expert Commentary
The study by Pitaro et al. provides valuable insight into the nuanced interplay between cardiac and renal dysfunction in patients undergoing PCI. The elevated mortality and MI risk linked to reduced LVEF in CKD patients aligns with pathophysiological expectations, as impaired ventricular function exacerbates myocardial vulnerability.
However, the absence of a significant difference in composite MACE between LVEF strata among CKD patients may be attributed to competing risks such as non-cardiac mortality or the influence of other vascular comorbidities common in CKD. It also underlines the complexity of managing this cohort where multifactorial risks coexist.
This study’s strengths include a large sample size, extended follow-up, and comprehensive risk assessment. Limitations include the observational design that precludes causality inference, single-center data limiting broader generalizability, and potential residual confounding. Further prospective research might explore mitigation strategies, including tailored pharmacological or interventional approaches in patients presenting with combined CKD and reduced ventricular function.
Conclusion
Reduced LVEF is a significant adverse prognostic marker for mortality and myocardial infarction in patients with chronic kidney disease undergoing PCI. Though composite cardiovascular event rates may not differ markedly, the elevated risk of death and MI underscores the need for careful cardiovascular surveillance and intervention in this subgroup. This evidence supports the integration of left ventricular function assessment into the risk stratification paradigm for CKD patients undergoing coronary revascularization. Future studies should aim to optimize management protocols aimed at improving outcomes in this high-risk population.
References
1. Pitaro N, Nicolas J, Sartori S, et al. Impact of left ventricular function on outcomes in patients with chronic kidney disease undergoing percutaneous coronary intervention. Am Heart J. 2025 Dec;290:180-187. doi: 10.1016/j.ahj.2025.06.017. Epub 2025 Jul 1. PMID: 40609714.
2. Foley RN, Parfrey PS, Sarnak MJ. Clinical epidemiology of cardiovascular disease in chronic renal disease. Am J Kidney Dis. 1998;32(5 Suppl 3):S112-9.
3. Bangalore S, Kumar S, Fusaro M, Amoroso N, Attubato MJ, Feit F, Bhatt DL, Berger PB, Farkouh ME. Percutaneous coronary intervention in Chronic Kidney Disease: Evidence and expert opinion. Int J Cardiol. 2015;188:46-54.
4. Zoccali C, Benedetto FA, Tripepi G, et al. Left ventricular hypertrophy and prognosis in end-stage renal disease patients: a prospective cohort study. Kidney Int. 2005;67(4):1517-1523.