Association between inflammatory cytokines and long-term adverse outcomes in acute coronary syndromes: A systematic review

Preoperative C-reactive protein/albumin ratio and mortality of off-pump coronary artery bypass graft

Background

We sought to investigate the prognostic value of preoperative C-reactive protein (CRP)-to-albumin ratio (CAR) for the prediction of mortality in patients undergoing off-pump coronary artery bypass grafting (OPCAB).

Methods

From January 2010 to August 2016, adult patients undergoing OPCAB were analyzed retrospectively. In a total of 2,082 patients, preoperative inflammatory markers including CAR, CRP, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio were recorded. Receiver operating characteristic (ROC) curves were used to determine the optimal threshold and compare the predictive values of the markers. The patients were divided into two groups according to the cut-off value of CAR, and then the outcomes were compared. The primary end point was 1-year mortality.

Results

During the 1-year follow-up period, 25 patients (1.2%) died after OPCAB. The area under the curve of CAR for 1-year mortality was 0.767, which was significantly higher than other inflammatory markers. According to the calculated cut-off value of 1.326, the patients were divided into two groups: 1,580 (75.9%) patients were placed in the low CAR group vs. 502 (24.1%) patients in the high CAR group. After adjustment with inverse probability weighting, high CAR was significantly associated with increased risk of 1-year mortality after OPCAB (Hazard ratio, 5.01; 95% Confidence interval, 2.01-12.50; p < 0.001).

Conclusions

In this study, we demonstrated that preoperative CAR was associated with 1-year mortality following OPCAB. Compared to previous inflammatory markers, CAR may offer superior predictive power for mortality in patients undergoing OPCAB. For validation of our findings, further prospective studies are needed.

Dynamic vagal-mediated connectivity of cortical and subcortical central autonomic hubs predicts chronotropic response to submaximal exercise in healthy adults

BACKGROUND

Despite accumulation of a substantial body of literature supporting the role of exercise on frontal lobe functioning, relatively less is understood of the interconnectivity of ventromedial prefrontal cortical (vmPFC) regions that underpin cardio-autonomic regulation predict cardiac chronotropic competence (CC) in response to sub-maximal exercise.

METHODS

Eligibility of 161 adults (mean age = 48.6, SD = 18.3, 68% female) was based upon completion of resting state brain scan and sub-maximal bike test. Sliding window analysis of the resting state signal was conducted over 45-s windows, with 50% overlap, to assess how changes in photoplethysmography-derived HRV relate to vmPFC functional connectivity with the whole brain. CC was assessed based upon heart rate (HR) changes during submaximal exercise (HR change /HRmax (206-0.88 × age) - HRrest).

RESULTS

During states of elevated HRV the vmPFC showed greater rsFC with an 83-voxel region of the hypothalamus (p < 0.001, uncorrected). Beta estimates of vmPFC connectivity extracted from a 6-mm sphere around this region emerged as the strongest predictor of CC (b = 0.283, p <.001) than age, BMI, and resting HRV F(8,144) = 6.30, p <.001.

CONCLUSION

Extensive glutamatergic innervation of the hypothalamus by the vmPFC allows for top-down control of the hypothalamus and its various autonomic efferents which facilitate chronotropic response during sub-maximal exercise.

Differential gene expression patterns in ST-elevation Myocardial Infarction and Non-ST-elevation Myocardial Infarction

The ST-elevation Myocardial Infarction (STEMI) and Non-ST-elevation Myocardial Infarction (NSTEMI) might occur because of coronary artery stenosis. The gene biomarkers apply to the clinical diagnosis and therapeutic decisions in Myocardial Infarction. The aim of this study was to introduce, enrich and estimate timely the blood gene profiles based on the high-throughput data for the molecular distinction of STEMI and NSTEMI. The text mining data (50 genes) annotated with DisGeNET data (144 genes) were merged with the GEO gene expression data (5 datasets) using R software. Then, the STEMI and NSTEMI networks were primarily created using the STRING server, and improved using the Cytoscape software. The high-score genes were enriched using the KEGG signaling pathways and Gene Ontology (GO). Furthermore, the genes were categorized to determine the NSTEMI and STEMI gene profiles. The time cut-off points were identified statistically by monitoring the gene profiles up to 30 days after Myocardial Infarction (MI). The gene heatmaps were clearly created for the STEMI (high-fold genes 69, low-fold genes 45) and NSTEMI (high-fold genes 68, low-fold genes 36). The STEMI and NSTEMI networks suggested the high-score gene profiles. Furthermore, the gene enrichment suggested the different biological conditions for STEMI and NSTEMI. The time cut-off points for the NSTEMI (4 genes) and STEMI (13 genes) gene profiles were established up to three days after Myocardial Infarction. The study showed the different pathophysiologic conditions for STEMI and NSTEMI. Furthermore, the high-score gene profiles are suggested to measure up to 3 days after MI to distinguish the STEMI and NSTEMI.

Inflammatory plasma proteins predict short-term mortality in patients with an acute myocardial infarction

BACKGROUND

The aim of this study was to investigate the association between inflammatory markers and 28-day mortality in patients with ST-elevation myocardial infarction (STEMI).

METHODS

In 398 STEMI patients recorded between 2009 and 2013 by the population-based Myocardial Infarction Registry Augsburg, 92 protein biomarkers were measured in admission arterial blood samples using the OLINK inflammatory panel. In multivariable-adjusted logistic regression models, the association between each marker and 28-day mortality was investigated. The values of the biomarkers most significantly associated with mortality were standardized and summarized to obtain a prediction score for 28-day mortality. The predictive ability of this biomarker score was compared to the established GRACE score using ROC analysis. Finally, a combined total score was generated by adding the standardized biomarker score to the standardized GRACE score.

RESULTS

The markers IL-6, IL-8, IL-10, FGF-21, FGF-23, ST1A1, MCP-1, 4E-BP1, and CST5 were most significantly associated with 28-day mortality, each with FDR-adjusted (false discovery rate adjusted) p-values of < 0.01 in the multivariable logistic regression model. In a ROC analysis, the biomarker score and the GRACE score showed comparable predictive ability for 28-day mortality (biomarker score AUC: 0.7859 [CI: 0.6735-0.89], GRACE score AUC: 0.7961 [CI: 0.6965-0.8802]). By combining the biomarker score and the Grace score, the predictive ability improved with an AUC of 0.8305 [CI: 0.7269-0.9187]. A continuous Net Reclassification Improvement (cNRI) of 0.566 (CI: 0.192-0.94, p-value: 0.003) and an Integrated Discrimination Improvement (IDI) of 0.083 ((CI: 0.016-0.149, p-value: 0.015) confirmed the superiority of the combined score over the GARCE score.

CONCLUSIONS

Inflammatory biomarkers may play a significant role in the pathophysiology of acute myocardial infarction (AMI) and AMI-related mortality and might be a promising starting point for personalized medicine, which aims to provide each patient with tailored therapy.

Acute-Phase Inflammatory Reaction Predicts CMR Myocardial Scar Pattern and 2-Year Mortality in STEMI Patients Undergoing Primary PCI

(1) Background: The inflammatory response following MI plays an important role in the healing, scar formation, and left ventricle (LV) remodeling. Cardiac magnetic resonance (CMR) imaging can accurately quantify the extent of myocardial scarring. The study aimed to investigate: (a) the relationship between acute inflammatory response and the CMR parameters of the scarring extent, and (b) the predictive power of inflammatory biomarkers and myocardial scarring for 2-year mortality. (2) Methods: The study included 202 STEMI patients, who underwent pPCI. Serum hs-CRP, IL-6, P-selectin, E-selectin, I-CAM, and V-CAM levels were determined at admission, and hs-CRP on the fifth day. Patients underwent LGE-CMR after 1 month, for LV volumes, ejection fraction (EF), infarct size (IS), and transmurality. Subjects were divided into tertiles according to the IS, and 2-year all-cause mortality was determined. (3) Results: IL-6 was associated with IS (r = 0.324, p = 0.01), increased transmurality index (r = 0.3, p = 0.01), and lower LVEF (r = −0.3, p = 0.02). Admission hs-CRP levels were not associated with IS, transmurality, or mortality, while hs-CRP at day 5 was a significant predictor for IS (AUC = 0.635, p = 0.05) as well as IL-6 levels (AUC = 0.685, p < 0.001). Mortality was significantly higher in the upper IS tertiles (6% vs. 8.7% vs. 24.52%, p = 0.005). IS was a significant predictor of 2-year mortality (AUC = 0.673, p = 0.002), with a cut-off value of 28.81 g, as well as high transmurality (AUC = 0.641, p = 0.013), with a cut off value of 18.38 g. (4) Conclusions: The serum levels of IL-6 and day-5 hs-CRP predict IS and transmurality, and day-5 hs-CRP levels are independent predictors of 2-year mortality in STEMI patients treated with pPCI. The CMR pattern of myocardial scarring after 1 month, as expressed by the magnitude of IS and transmurality, is a significant predictor for 2-year mortality after revascularized STEMI.

Predicting cardiovascular risk using a novel risk score in young and middle-age adults with HIV: associations with biomarkers and carotid atherosclerotic plaque

BACKGROUND

Traditional risk factors associated with cardiovascular disease (CVD) include older age, smoking, poor diet, lack of exercise, obesity, high blood pressure, high cholesterol, and family history. Young-to-middle age adults (YMAA) are less often identified as being at risk of CVD, but traditional risk scores primarily target older adults and do not accurately estimate risk among YMAA.

METHODS

This study examined biomarkers associated with CVD risk in YMAA in the context of HIV and cocaine use; risk was assessed by two methods: (1) a relative cardiovascular (CV) risk score that includes several factors and (2) carotid atherosclerotic plaque. Associations between CVD risk (CV risk score and carotid atherosclerotic plaque) and proinflammatory cytokines, markers of immune activation, HIV status, and cocaine use were examined. Participants (N = 506) included people with and without HIV and people who use or do not use cocaine.

RESULTS

Participants' mean age was 36 (SD = 9.53); half (51%) were men. Cocaine use and C-reactive protein were associated with greater relative CV risk scores, but no associations between biomarkers and CV risk emerged. Age and CV risk scores were associated with carotid atherosclerotic plaque, but biomarkers were not. HIV was not associated with CV risk scores or carotid atherosclerotic plaque.

CONCLUSIONS

Among YMAA, CV risk scores may help providers identify lifestyle changes needed among those at risk for CVD before more advanced risk (e.g., atherosclerotic plaque) is identified. Implications are discussed.

IL-6, IL-1RA and Resistin as Predictors of Left Ventricular Remodelling and Major Adverse Cardiac Events in Patients with Acute ST Elevation Myocardial Infarction

Despite continuous advances in diagnostic and therapeutic methods, acute myocardial infarction (AMI) remains a leading cause of morbidity and mortality worldwide. Considering the role of inflammation in AMI etiopathogenesis, we aimed to explore the role of a group of three inflammatory cytokines (IL-1RA, IL-6 and resistin) as an independent prognostic factor for LVR assessed by 3D echocardiography and MACE in patients with STEMI. We enrolled 41 patients with STEMI who underwent primary PCI. We assessed the occurrence of LVR (defined as an increase of over 20% in end-diastolic left ventricular volume at 6 months compared with baseline values) and MACE. Using the enzyme-linked immunosorbent assays (ELISA) method, we measured plasmatic levels of IL-6, IL-1RA and resistin (within 48 h after AMI and at 6 months). Out of 41 STEMI patients, 20.5% presented signs of LVR at follow up, and in 24.4%, MACE occurred. In univariate logistic regression analysis, baseline levels of IL-6 (OR = 1.042, p = 0.004), IL-1RA (OR = 1.004, p = 0.05) and resistin (OR = 1.7, p = 0.007) were all significantly associated with LVR. ROC analysis showed that the three cytokines as a group (AUC 0.946, p = 0.000) have a better predictive value for LVR than any individual cytokine. The group of cytokines also proved to have a better predictive value for MACE together than separately (AUC = 0.875, p = 0.000 for ROC regression model). IL-6, IL-1RA and resistin plasma levels at baseline have a good predictive value both as independent variables and also as a group for the development of adverse LVR and MACE at 6 months follow up after STEMI.

PPARβ/δ Is Required for Mesenchymal Stem Cell Cardioprotective Effects Independently of Their Anti-inflammatory Properties in Myocardial Ischemia-Reperfusion Injury

Myocardial infarction ranks first for the mortality worldwide. Because the adult heart is unable to regenerate, fibrosis develops to compensate for the loss of contractile tissue after infarction, leading to cardiac remodeling and heart failure. Adult mesenchymal stem cells (MSC) regenerative properties, as well as their safety and efficacy, have been demonstrated in preclinical models. However, in clinical trials, their beneficial effects are controversial. In an experimental model of arthritis, we have previously shown that PPARβ/δ deficiency enhanced the therapeutic effect of MSC. The aim of the present study was to compare the therapeutic effects of wild-type MSC (MSC) and MSC deficient for PPARβ/δ (KO MSC) perfused in an ex vivo mouse model of ischemia-reperfusion (IR) injury. For this purpose, hearts from C57BL/6J mice were subjected ex vivo to 30 min ischemia followed by 1-h reperfusion. MSC and KO MSC were injected into the Langendorff system during reperfusion. After 1 h of reperfusion, the TTC method was used to assess infarct size. Coronary effluents collected in basal condition (before ischemia) and after ischemia at 1 h of reperfusion were analyzed for their cytokine profiles. The dose-response curve for the cardioprotection was established ex vivo using different doses of MSC (3.10⁵, 6.10⁵, and 24.10⁵ cells/heart) and the dose of 6.10⁵ MSC was found to be the optimal concentration. We showed that the cardioprotective effect of MSC was PPARβ/δ-dependent since it was lost using KO MSC. Moreover, cytokine profiling of the coronary effluents collected in the eluates after 60 min of reperfusion revealed that MSC treatment decreases CXCL1 chemokine and interleukin-6 release compared with untreated hearts. This anti-inflammatory effect of MSC was also observed when hearts were treated with PPARβ/δ-deficient MSC. In conclusion, our study revealed that the acute cardioprotective properties of MSC in an ex vivo model of IR injury, assessed by a decreased infarct size at 1 h of reperfusion, are PPARβ/δ-dependent but not related to their anti-inflammatory effects.

Systemic Vulnerability, as Expressed by I-CAM and MMP-9 at Presentation, Predicts One Year Outcomes in Patients with Acute Myocardial Infarction-Insights from the VIP Clinical Study

(1) Background: The prediction of recurrent events after acute myocardial infarction (AMI) does not sufficiently integrate systemic inflammation, coronary morphology or ventricular function in prediction algorithms. We aimed to evaluate the accuracy of inflammatory biomarkers, in association with angiographical and echocardiographic parameters, in predicting 1-year MACE after revascularized AMI. (2) Methods: This is an extension of a biomarker sub-study of the VIP trial (NCT03606330), in which 225 AMI patients underwent analysis of systemic vulnerability and were followed for 1 year. Hs-CRP, MMP-9, IL-6, I-CAM, V-CAM and E-selectin were determined at 1 h after revascularization. The primary end-point was the 1-year MACE rate. (3) Results: The MACE rate was 24.8% (n = 56). There were no significant differences between groups in regard to IL-6, V-CAM and E-selectin. The following inflammatory markers were significantly higher in MACE patients: hs-CRP (11.1 ± 13.8 vs. 5.1 ± 4.4 mg/L, p = 0.03), I-CAM (452 ± 283 vs. 220.5 ± 104.6, p = 0.0003) and MMP-9 (2255 ± 1226 vs. 1099 ± 706.1 ng/mL p = 0.0001). The most powerful predictor for MACE was MMP-9 of >1155 ng/mL (AUC-0.786, p < 0.001) even after adjustments for diabetes, LVEF, acute phase complications and other inflammatory biomarkers. For STEMI, the most powerful predictors for MACE included I-CAM > 239.7 ng/mL, V-CAM > 877.9 ng/mL and MMP-9 > 1393 ng/mL. (4) Conclusions: High levels of I-CAM and MMP-9 were the most powerful predictors for recurrent events after AMI for the overall study population. For STEMI subjects, the most important predictors included increased levels of I-CAM, V-CAM and MMP-9, while none of the analyzed parameters had proven to be predictive. Inflammatory biomarkers assayed during the acute phase of AMI presented a more powerful predictive capacity for MACE than the LVEF.

An IL-6-IL-8 score derived from principal component analysis is predictive of adverse outcome in acute myocardial infarction

Introduction

Many studies have shown that elevated biomarkers of inflammation following acute myocardial infarction (AMI) are associated with major adverse cardiovascular events (MACE). However, the optimal way of measuring the complex inflammatory response following AMI has not been determined. In this study we explore the use of principal component analysis (PCA) utilising multiple inflammatory cytokines to generate a combined cytokine score that may be predictive of MACE post-AMI.

Methods

Thirteen inflammatory cytokines were measured in plasma of 317 AMI patients, drawn 48-72 h following symptom onset. Patients were followed-up for one year to determine the incidence of MACE. PCA was used to generate a combined score using six cytokines that were detectable in the majority of patients (IL-1β, -6, -8, and -10; MCP-1; and RANTES), and using a subset of cytokines that were associated with MACE on univariate analysis. Multivariate models using baseline characteristics, elevated individual cytokines and PCA-derived scores determined independent predictors of MACE.

Results

IL-6 and IL-8 were significantly associated with MACE on univariate analysis and were combined using PCA into an IL-6-IL-8 score. The combined cytokine score and IL-6-IL-8 PCA-derived score were both significantly associated with MACE on univariate analysis. In multivariate models IL-6-IL-8 scores (OR = 2.77, p = 0.007) and IL-6 levels (OR = 2.18, p = 0.035) were found to be independent predictors of MACE.

Conclusion

An IL-6-IL-8 score derived from PCA was found to independently predict MACE at one year and was a stronger predictor than any individual cytokine, which suggests this may be an appropriate strategy to quantify inflammation post-AMI. Further investigation is required to determine the optimal set of cytokines to measure in this context.