Contrast-Associated Acute Kidney Injury: Comprehensive Review of Risk Factors, Pathophysiology, Definition and Management.

Abstract

Contrast-associated acute kidney injury (CA-AKI) remains an important clinical concern, especially as percutaneous coronary interventions (PCI) are being increasingly performed. This review provides a comprehensive, evidence-based synthesis of CA-AKI, acknowledging a shift in terminology from "contrast-induced" to "contrast-associated" to reflect the interplay of co-existing non-contrast factors and patient comorbidities. A comprehensive literature search was performed in PubMed/MEDLINE, Embase, and the Cochrane Library from inception through June 2025 using terms related to contrast-associated acute kidney injury, risk factors, pathophysiology, prevention, and management; studies were selected based on relevance, methodological quality, and clinical applicability. While the exact causal relationship between contrast exposure and AKI is debated, CA-AKI is associated with adverse outcomes, including prolonged hospitalization, increased healthcare costs, and higher morbidity and mortality, as well as procedural variables such as contrast volume. Pathophysiological mechanisms include afferent arteriolar dilatation, medullary ischemia, direct tubular epithelial injury, and mitochondrial dysfunction, which can lead to maladaptive repair and progression to CKD. Management focuses on preventive strategies- maintaining hemodynamic stability, optimizing volume status, minimizing contrast dose, and implementing nephrotoxin stewardship. Despite the use of validated risk scores and emerging biomarkers for earlier detection, management remains largely supportive. Future paradigms emphasize individualized clinical decision-making, digital health solutions, and the potential for targeted therapies to prevent the AKI-to-CKD transition.