Prognostic utility of neutrophil gelatinase-associated lipocalin in predicting mortality and cardiovascular events in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention.

Objectives: The aim of this study was to investigate the prognostic role of neutrophil gelatinase-associated lipocalin (NGAL) in a large population of patients with ST-segment elevation myocardial infarction.

Background: NGAL is a glycoprotein released by damaged renal tubular cells and is a sensitive maker of both clinical and subclinical acute kidney injury. New data have demonstrated that NGAL is also stored in granules of mature neutrophils, and recent data suggest that NGAL may also be involved in the development of atherosclerosis. NGAL is significantly increased in patients with myocardial infarction compared with patients with stable coronary artery disease and healthy subjects. However, the prognostic value of NGAL has never been studied in patients with myocardial infarction.

Methods: We included 584 consecutive ST-segment elevation myocardial infarction patients admitted to the heart center of Gentofte University Hospital, Denmark, and treated with primary percutaneous coronary intervention, from September 2006 to December 2008. Blood samples were drawn immediately before primary percutaneous coronary intervention. Plasma NGAL levels were measured using a time-resolved immunofluorometric assay. The endpoints were all-cause mortality (n = 69) and the combined endpoints (n = 116) of major adverse cardiac events (MACE) defined as cardiovascular mortality and admission due to recurrent myocardial infarction or heart failure. The median follow-up time was 23 months (interquartile range, 20 to 24 months).

Results: Patients with high NGAL (>75th percentile) had increased risk of all-cause mortality and MACE compared with patients with low NGAL (log-rank test, p < 0.001). After adjustment for confounding risk factors chosen by backward elimination by Cox regression analysis, high NGAL remained an independent predictor of all-cause mortality and MACE (hazard ratio: 2.00; 95% confidence interval: 1.16 to 3.44; p = 0.01 and hazard ratio: 1.51; 95% confidence interval: 1.00 to 2.30; p = 0.05, respectively).

Conclusions: High plasma NGAL independently predicts all-cause mortality and MACE in ST-segment elevation myocardial infarction patients treated with primary percutaneous coronary intervention.