Predicting Contrast-induced Renal Complications.

Chronic kidney disease is an independent risk factor for the development of coronary artery disease and overlaps with other risk factors such as hypertension and diabetes. Percutaneous coronary intervention is a cornerstone of therapy for coronary artery disease and requires contrast media, which can lead to renal injury. Identifying patients at risk for contrast-associated acute kidney injury (CA-AKI) is critical for preventing kidney damage, which is associated with both short- and long-term mortality. Determination of the potential risk for CA-AKI and a new need for dialysis using validated risk prediction tools identifies patients at high risk for this complication. Identification of patients at risk for renal injury after contrast exposure is the first critical step in prevention. Contrast media volume, age and sex of the patient, a history of chronic kidney disease and/or diabetes, clinical presentation, and hemodynamic and volume status are factors known to predict incident contrast-induced nephropathy. Recognition of at-risk patient subpopulations allows for targeted, efficient, and cost-effective strategies to reduce the risk of renal complications resulting from contrast media exposure.

Circulating Ectonucleotidases Signal Impaired Myocardial Perfusion at Rest and Stress.

Background Ectonucleotidases maintain vascular homeostasis by metabolizing extracellular nucleotides, modulating inflammation and thrombosis, and potentially, myocardial flow through adenosine generation. Evidence implicates dysfunction or deficiency of ectonucleotidases CD39 or CD73 in human disease; the utility of measuring levels of circulating ectonucleotidases as plasma biomarkers of coronary artery dysfunction or disease has not been previously reported. Methods and Results A total of 529 individuals undergoing clinically indicated positron emission tomography stress testing between 2015 and 2019 were enrolled in this single-center retrospective analysis. Baseline demographics, clinical data, nuclear stress test, and coronary artery calcium score variables were collected, as well as a blood sample. CD39 and CD73 levels were assessed as binary (detectable, undetectable) or continuous variables using ELISAs. Plasma CD39 was detectable in 24% of White and 8% of Black study participants (P=0.02). Of the clinical history variables examined, ectonucleotidase levels were most strongly associated with underlying liver disease and not other traditional coronary artery disease risk factors. Intriguingly, detection of circulating ectonucleotidase was inversely associated with stress myocardial blood flow (2.3±0.8 mL/min per g versus 2.7 mL/min per g±1.1 for detectable versus undetectable CD39 levels, P<0.001) and global myocardial flow reserve (Pearson correlation between myocardial flow reserve and log(CD73) -0.19, P<0.001). A subanalysis showed these differences held true independent of liver disease. Conclusions Vasodilatory adenosine is the expected product of local ectonucleotidase activity, yet these data support an inverse relationship between plasma ectonucleotidases, stress myocardial blood flow (CD39), and myocardial flow reserve (CD73). These findings support the conclusion that plasma levels of ectonucleotidases, which may be shed from the endothelial surface, contribute to reduced stress myocardial blood flow and myocardial flow reserve.

Predicting Contrast-Induced Renal Complications.

Chronic kidney disease is a major risk factor for developing coronary artery disease, serving as an independent risk factor while overlapping with other risk factors. Percutaneous coronary intervention is a cornerstone of therapy for coronary artery disease and requires contrast media, which can contribute to renal injury. Identifying patients at risk for contrast-induced nephropathy is critical for preventing renal injury, which is associated with short- and long-term mortality. Determination of the potential risk for contrast-induced nephropathy and a new need for dialysis using validated risk prediction tools is a method of identifying patients at high risk for this complication.