Elevated renalase levels in patients with acute coronary microvascular dysfunction – A possible biomarker for ischemia. (15th March 2019)

• Record Type: Journal Article
• Authors: Safdar, Basmah; Guo, Xiaojia; Johnson, Caitlin; D'Onofrio, Gail; Dziura, James; Sinusas, Albert J.; Testani, Jeffrey; Rao, Veena; Desir, Gary
• Is Part Of: International journal of cardiology. Volume 279(2019)
• Page Start: 155
• Page End: 161
• Publication Date: 2019-03-15
• Subjects: Coronary microvascular dysfunction -- PET -- Chest pain -- Renalase -- Biomarker -- Inflammation; Cardiology -- Periodicals; Electronic journals; 616.12
• DOI: 10.1016/j.ijcard.2018.12.061
• Languages: English
• ISSNs: 0167-5273

Abstract

Abstract: Aims: We explored the relationship between inflammation, renalase an anti-inflammatory protein, and acute chest pain with coronary microvascular dysfunction (CMD). Methods and results: We used cardiac Rb-82 PET/CT imaging to diagnose coronary artery disease (CAD/CALC) (defect or coronary calcification) and CMD (depressed coronary flow reserve without CAD) in patients with chest pain in an emergency department (ED). Blood samples were collected pre-imaging within 24 h of ED presentation and were analyzed for renalase and inflammatory markers including C-reactive protein, interleukins, interferon gamma, tumor necrosis factor, vascular endothelial growth factor, and metalloproteinases. Exclusions were age ≤30 years, myocardial infarction, hemodynamic instability, hypertensive crisis, heart failure or dialysis. Between 6/2014 and 11/2015, 80 patients undergoing PET/CT provided blood and were categorized as normal (18%), CAD/CALC (27%) and CMD (55%). Median renalase values were highest in patients with CMD (5503 ng/ml; IQR 3070) compared to patients with normal flows (4266 ng/ml; IQR 1503; p = 0.02) or CAD/CALC (4069 ng/ml IQR 1850; p = 0.004). CMD patients had similar median values for inflammatory markers as normal patients (p > 0.05). Renalase remained an independent predictor of CMD (OR 1.34; 95% CI = 1.1–1.7, per 1000 ng/ml) after adjustment for smoking, family history, obesity and Framingham risk score. In a model for CMD diagnosis with Framingham risk score, typical angina history and CRP, renalase improved discrimination from C-statistic = 0.60 (95% CI 0.47, 0.73) to 0.70 (95% CI, 0.59–0.82). Conclusion: We found elevated renalase in response to ischemia from acute CMD. Its role as a biomarker needs validation in larger trials.