Neutrophil-to-lymphocyte ratio predicts response to cardiac resynchronization therapy

The neutrophil to lymphocyte ratio in heart failure: a comprehensive review

INTRODUCTION

Heart failure (HF) and systemic inflammation are interdependent processes that continuously potentiate each other. Distinct pathophysiological pathways are activated, resulting in increased neutrophil count and reduced lymphocyte numbers, making the neutrophil to lymphocyte ratio (NLR) a potential indirect marker of severity. We conducted this comprehensive review to characterize the role of NLR in HF.

METHODS

We searched the PubMed (MEDLINE) database using the key words "neutrophil", "lymphocyte", "heart failure", "cardiomyopathy", "implantable cardioverter defibrillator", "cardiac resynchronization therapy" and "heart transplant".

RESULTS

We identified 241 publications. 31 were selected for this review, including 12,107 patients. NLR was correlated to HF severity expressed by clinical, biological, and imaging parameters, as well as to short and long-term prognosis. Most studies reported its survival predictive value. Elevated NLR (>2.1-7.6) was an independent predictor of in-hospital mortality [adjusted HR 1.13 (95% CI 1.01-1.27) - 2.8 (95% CI 1.43-5.53)] as well as long-term all-cause mortality [adjusted HR 1.43 (95% CI 1.1-1.85) - 2.403 (95% CI 1.076-5.704)]. Higher NLR levels also predicted poor functional capacity [NLR > 2.26/2.74, HR 3.93 (95% CI 1.02-15.12) / 3.085 (95% CI 1.52-6.26)], hospital readmissions [NLR > 2.9/7.6, HR 1.46 (95% CI 1.10-1.93) / 3.46 (95% CI 2.11-5.68)] cardiac resynchronization therapy efficacy [NLR > 3.45/unit increase, HR 12.22 (95% CI 2.16-69.05) / 1.51 (95% CI 1.01-2.24)] and appropriate implantable cardioverter defibrillator shocks (NLR > 2.93), as well as mortality after left ventricular assist device implantation [NLR > 4.4 / quartiles, HR 1.67 (95% CI 1.03-2.70) / 1.22 (95% CI 1.01-1.47)] or heart transplant (NLR > 2.41, HR 3.403 (95% CI 1.04-11.14)].

CONCLUSION

Increased NLR in HF patients can be a valuable auxiliary biomarker of severity, and most of all, of poor prognosis.

The association of hematological indices with the response to cardiac resynchronization therapy: a single-center study

BACKGROUND

Cardiac resynchronization therapy (CRT) is an established therapeutic option for patients with heart failure (HF) and left ventricular ejection fraction (LVEF) ≤35 % who meet specific criteria according to current guidelines. However, up to 40 % of patients have no response to CRT. Our study aimed to investigate the association between different hematological and biochemical indices and response to CRT.

METHODS

Patients with HF due to ischemic or dilated cardiomyopathy referred to our hospital for CRT implantation from January 2013 to November 2017 were included in the study. Response to CRT was defined as an increase in LVEF ≥10 % or a decrease in left ventricular end-systolic volume (LVESV) ≥15 % at six months of follow-up.

RESULTS

A total of 48 patients (mean age: 66.2 ± 9.5 years, 81.3 % males) were included in the study. Of these HF patients, 29 (60.4 %) had ischemic cardiomyopathy, and 19 (39.6 %) had dilated cardiomyopathy. At six months of follow-up, 37 patients (77.1 %) had responded to CRT. Ten patients (20.8 %) had ventricular tachycardia (VT), 24 (50 %) patients were hospitalized, and two patients (4.2 %) died during the follow-up period. Multivariate analysis demonstrated that age (p =0.03) and creatinine levels (p =0.02) were independent predictors of the response to CRT. No significant associations between hematological markers (white blood cells, neutrophils, lymphocytes, platelets, neutrophil to lymphocyte ratio, red blood cells distribution width) and CRT response were observed.

CONCLUSIONS

A smaller increase in LVEF and a smaller decrease in LVESV were predictive for VT occurrence and hospitalizations in patients receiving CRT. No significant association between hematological markers and response to CRT was found. HIPPOKRATIA 2019, 23(3): 118-125.

Cellular and Molecular Aspects of Dyssynchrony and Resynchronization

Dyssynchronous contraction of the ventricle significantly worsens morbidity and mortality in patients with heart failure (HF). Approximately one-third of patients with HF have cardiac dyssynchrony and are candidates for cardiac resynchronization therapy (CRT). The initial understanding of dyssynchrony and CRT was in terms of global mechanics and hemodynamics, but lack of clinical benefit in a sizable subgroup of recipients who appear otherwise appropriate has challenged this paradigm. This article reviews current understanding of these cellular and subcellular mechanisms, arguing that these aspects are key to improving CRT use, as well as translating its benefits to a wider HF population.

Neutrophil to lymphocyte ratio (NLR) and cardiovascular diseases: an update

As we know, inflammatory and oxidative stresses have a role in the pathogenesis of cardiovascular disease. This knowledge has triggered many investigations targeted to inflammatory markers. One such example, the neutrophil to lymphocyte ratio (NLR), is an inexpensive and easily accessible inflammatory marker whose role in cardiovascular disease has been studied extensively in the past few years. The neutrophil lymphocyte ratio has been shown to predict cardiac arrhythmias as well as short- and long-term mortality in patients with acute coronary syndromes (ACS). It has correlated well with ACS risk prediction models such as the GRACE and SYNTAX scores. A higher NLR has also been associated with frequent congestive heart failure decompensation and long-term mortality. The neutrophil to lymphocyte ratio also appears to have a prognostic role in patients undergoing transaortic valve replacement and the progression of valvular heart diseases. Despite the science of inflammatory biomarkers having been described decades ago, NLR appears to be enjoying a renaissance as a cost-effective biomarker with immediate clinical predictability and prognostication.

Reduction of Leukocyte Counts by Hydroxyurea Improves Cardiac Function in Rats with Acute Myocardial Infarction

BACKGROUND This study aimed to decrease leukocytes counts by hydroxyurea (Hu) in an acute myocardial infarction (AMI) rat model and examine its effect on the inflammatory response of myocardial infarction and cardiac functions. MATERIAL AND METHODS AMI was successfully caused in 36 rats, and 12 control rats received sham operation. Rats in the AMI group were then randomly divided into Hu and vehicle group with 18 rats each. Rats in the Hu AMI group received Hu (200 mg/kg) intragastrically while vehicle AMI group received saline. Leukocytes counts, cardiac functions, myocardial tissue morphology, and levels of soluble intercellular adhesion molecule-1 (sICAM), P-selectin and platelet activating factor (PAF) were measured and compared among the three groups four weeks after AMI induction. RESULTS Leukocytes, neutrophils, and leukomonocyte counts in vehicle AMI rats were significantly higher than that of the normal control group (p<0.05). However, Hu treatment decreased their counts significantly (p<0.05). sICAM, P-selectin, and PAF level in vehicle AMI group were significantly higher than those of the normal group, and their level was also decreased by Hu treatment (p<0.05). Echocardiography analysis showed that Hu treatment increased left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) compared to that of vehicle AMI group (p<0.05). Histopathological examination showed that Hu significantly reduced the swelling of the heart muscle fiber in necrotic foci and the number of inflammatory cells infiltrated into myocardial interstitium compared to vehicle AMI group. CONCLUSIONS Decrease leukocytes counts by Hu significantly reduced inflammatory reaction and improved cardiac functions in AMI rats.

Cellular and Molecular Aspects of Dyssynchrony and Resynchronization

Dyssynchronous contraction of the ventricle significantly worsens morbidity and mortality in patients with heart failure (HF). Approximately one-third of patients with HF have cardiac dyssynchrony and are candidates for cardiac resynchronization therapy (CRT). The initial understanding of dyssynchrony and CRT was in terms of global mechanics and hemodynamics, but lack of clinical benefit in a sizable subgroup of recipients who appear otherwise appropriate has challenged this paradigm. This article reviews current understanding of these cellular and subcellular mechanisms, arguing that these aspects are key to improving CRT use, as well as translating its benefits to a wider HF population.

The ratio of the neutrophil leucocytes to the lymphocytes predicts the outcome after cardiac resynchronization therapy

Aims

The low lymphocyte counts and high neutrophil leucocyte fractions have been associated with poor prognosis in chronic heart failure. We hypothesized that the baseline ratio of the neutrophil leucocytes to the lymphocytes (NL ratio) would predict the outcome of chronic heart failure patients undergoing cardiac resynchronization therapy (CRT).

Methods and results

The qualitative blood counts and the serum levels of N-terminal of the prohormone brain natriuretic peptide (NT-proBNP) of 122 chronic heart failure patients and 122 healthy controls were analysed prospectively in this observational study. The 2-year mortality was considered as primary endpoint and the 6-month reverse remodelling (≥15% decrease in the end-systolic volume) as secondary endpoint. Multivariable regression analyses were applied and net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were calculated. The NL ratio was elevated in chronic heart failure patients when compared with the healthy controls [2.93 (2.12–4.05) vs. 2.21 (1.64–2.81), P < 0.0001]. The baseline NL ratio exceeding 2.95 predicted the lack of the 6-month reverse remodelling [n = 63, odds ratio = 0.38 (0.17–0.85), P = 0.01; NRI = 0.49 (0.14–0.83), P = 0.005; IDI = 0.04 (0.00–0.07), P = 0.02] and the 2-year mortality [n = 29, hazard ratio = 2.44 (1.04–5.71), P = 0.03; NRI = 0.63 (0.24–1.01), P = 0.001; IDI = 0.04 (0.00–0.08), P = 0.02] independently of the NT-proBNP levels or other factors.

Conclusion

The NL ratio is elevated in chronic heart failure and predicts outcome after CRT. According to the reclassification analysis, 4% of the patients would have been better categorized in the prediction models by combining the NT-proBNP with the NL ratio. Thus, a single blood count measurement could facilitate the optimal patient selection for the CRT.

What is the lowest value of left ventricular baseline ejection fraction that predicts response to cardiac resynchronization therapy?

Background

Cardiac resynchronization therapy (CRT) is an effective treatment option for patients with refractory heart failure. However, many patients do not respond to therapy. Although it has been thought that there was no relation between response to CRT and baseline ejection fraction (EF), the response rate of patients with different baseline LVEF to CRT has not been evaluated in severe left ventricular systolic dysfunction. We aimed to investigate any difference in response to CRT between the severe heart failure patients with different baseline LVEF.

Material/Methods

In this study, 141 consecutive patients (mean age 59±13 years; 89 men) with severe heart failure and complete LBBB were included. Patients were divided into 3 groups according to their baseline LVEF: 5–15%, Group 1; 15–25%, Group 2, and 25–35%, Group 3. NYHA functional class, LVEF, LV volumes, and diameters were assessed at baseline and after 6 months of CRT. A response to CRT was defined as a decrease in LVSVi (left ventricular end-systolic volume index) ≥10% on echocardiography at 6 months.

Results

After 6 months, a significant increase of EF and a significant decrease of LVESVi and LVEDVi after 6 months of CRT were observed in all groups. Although the magnitude of improvement in EF was biggest in the first group, the percentage of decrease in LVESVi and LVEDVi was similar between the groups. The improvement in NYHA functional class was similar in all EF subgroups. At 6-month follow-up, 100 (71%) patients showed a reduction of >10% in LVESVi (mean reduction: −15.5±26.1 ml/m²) and were therefore classified as responders to CRT. Response rate to CRT was similar in all groups. It was 67%, 75%, and 70% in Group 1, 2, and 3, respectively, at 6-month follow-up (p>0.05). There was no statistically significant relation between the response rate to CRT and baseline LVEF, showing that the CRT has beneficial effects even in patients with very low LVEF.

Conclusions

It seems there is no lower limit for baseline LVEF to predict non-response to CRT in eligible patients according to current guidelines.

Neutrophil/lymphocyte ratio is related to the severity of idiopathic dilated cardiomyopathy

OBJECTIVES

The aim of this study was to assess whether NLR levels are associated with echocardiographic parameters, New York Heart Association (NYHA) functional class, or B- type natriuretic peptide (BNP) levels in patients with idiopathic dilated cardiomyopathy (DCM).

DESIGN

Eighty-seven patients with idiopathic DCM were included prospectively from 2009 to 2014. Patients with acute decompensated heart failure and conditions that alter the total or differential white blood cell counts were excluded. Blood samples were collected before echocardiographic investigation on admission.

RESULTS

There was a statistically significant correlation between neutrophil/lymphocyte ratio (NLR) and NYHA functional class (r = 0.68, p < 0.001), BNP levels (r = 0.61, p < 0.001) and various echocardiographic parameters. NLR was significantly higher in patients in NYHA functional class III or IV (n = 39) than among those categorized as NYHA class I or II (n = 48), (3.3 ± 1.0 vs 2.1 ± 0.6; p < 0.001). The NLR cutoff value predicting severe chronic HF was 2.25 with 82% sensitivity and 65% specificity (p < 0.001). On multivariate linear regression analysis NLR (p = 0.025), left ventricular end-diastolic volume (p = 0.041) and left atrial volume index (LAVI) (p = 0.001) were found to be independent positive predictors of BNP levels.

CONCLUSION

Neutrophil/Lymphocyte ratio is associated with the severity of chronic heart failure in patients with idiopathic DCM.

The Association Between the Neutrophil-to-Lymphocyte Ratio and the Presence of Ventricular Premature Contractions in Young Adults

Inflammation has recently emerged in the pathogenesis of several cardiovascular disorders, including arrhythmias. The neutrophil-lymphocyte ratio (NLR) is a simple marker for the assessment of inflammatory status. Therefore, we aimed to investigate the relationship between the NLR and the ventricular premature contraction (VPC) existence. Patients aged between 18 and 40 years who were referred to the cardiology clinic were enrolled in the study. All patients' complete blood counts and 24-hour Holter recordings were analyzed. The NLR was higher within the VPC group compared to the control group (P < .001). According to the NLR tertiles, VPCs were more common in the higher NLR tertile (P < .001). A cutoff point of 1.80 for the NLR had 71% sensitivity and 60% specificity in predicting VPC in apparently healthy individuals. After multivariate analysis, only the NLR remained significant predictor of presence of VPC. In conclusion, the NLR is independently and significantly associated with VPC existence.