The relationship between neutrophil gelatinase-associated lipocalin levels and the slow coronary flow phenomenon.

Objectives: There is accumulating evidence that inflammation plays a major role in the development of the slow coronary flow (SCF) phenomenon. In this study, we aimed to study the biomarker neutrophil gelatinase-associated lipocalin (NGAL) as it relates to SCF.

Materials And Methods: Patients who underwent coronary angiography before and had no significant epicardial coronary disease were included in the study. Patients who had Thrombolysis in Myocardial Infarction frame counts (TFCs) above the normal cutoffs were considered to have SCF and those within normal limits were considered to have normal coronary flow (NCF). The NGAL levels and biochemical profiles of all patients were studied and analyzed with coronary flow parameters.

Results: There were 50 patients in the SCF group and 50 patients in the NCF group. The serum NGAL level was higher in those patients in the SCF group versus the NCF group (75.2±39.7 vs. 50.6±24.2, P<0.001). There was a significant correlation between the NGAL levels and TFC (r=0.684, P<0.001). Multivariable regression analysis showed that the NGAL levels were an independent predictor of the SCF phenomenon (odds ratio=1.060, 95% confidence interval: 1.008-1.115, P=0.023).

Conclusion: In this study, we show that patients with SCF have elevated levels of NGAL. We further show a strong correlation between the NGAL levels and coronary blood flow. We conclude that elevated NGAL levels might be a useful tool in predicting SCF in patients who undergo coronary angiography.