The Neutrophil–Lymphocyte Ratio Is Associated with Cardiac Magnetic Resonance Imaging-Derived Myocardial Fibrosis

TL;DR

This study finds that a blood test measuring neutrophil-lymphocyte ratio is linked to signs of heart tissue scarring seen on MRI scans.

Contribution

The novel contribution is showing that a simple blood test (NLR) correlates with myocardial fibrosis detected via cardiac MRI.

Findings

Higher NLR tertiles correlated with lower ejection fraction and increased right ventricular volume.

NLR was significantly associated with prolonged myocardial T1 times and increased extracellular volume (ECV).

CRP showed similar associations with T1 and ECV as NLR, but both explained only a modest portion of variation.

Abstract

Background: Sub-clinical inflammation is considered a key mechanism in cardiovascular disease and myocardial remodeling. We therefore evaluated whether the neutrophil–lymphocyte ratio (NLR), a simple inflammatory marker derived from a routine full blood count, is associated with myocardial fibrosis. Methods: Consecutive patients from a cardiac magnetic resonance imaging (CMR) registry were included and stratified by the NLR tertile. The association of the NLR and the levels of C-reactive protein (CRP) with CMR-derived myocardial T1 time and the extracellular volume fraction (ECV) were assessed using linear regression analysis and compared using Z-scores. In addition, an association with outcome was tested utilizing the log-rank test. Results: 1152 patients (72.4 years, 53.1% male) constituted the final cohort. The median NLR was 3.11 [interquartile range (IQR): 2.145–4.67]. Tertiles were based on the cut-off values ≤ 2.5, >2.5 and <4.0, and ≥4.0. A higher NLR tertile was associated with lower biventricular ejection fraction, hypertrophy, and increased right ventricular volume. The myocardial native T1 time [tertile 1 vs. 3: 1010 ms (984–1038) vs. 1030 (1001–1059), p < 0.001] and ECV [tertile 1 vs. 3: 26.3% (24.2–28.6) vs. 28.1% (25.5–31.4), p < 0.001] also significantly differed between the NLR tertiles. The NLR’s and the CRP’s association with elevated myocardial T1 time and ECV were comparable; however, the proportion of variation in the target variables explained by either was generally low. Conclusions: In our CMR all-comer cohort, NLR and CRP were significantly associated with prolonged myocardial T1 times and increased ECV. However, only a modest variation observed in both parameters was explained by either variable.

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