Novel cardiovascular biomarkers in patients with cardiovascular diseases undergoing intensive physical exercise

BACKGROUND

In this trial, we analyzed the plasma levels of novel biomarkers that reflect different pathophysiological pathways (sST2: mechanical strain, IGF-BP2: metabolic pathways, suPAR and GDF-15: inflammatory processes) in patients undergoing physical exercise to investigate the effects of training on their plasma concentrations.

METHODS

Plasma concentrations of novel biomarkers (sST2, IGF-BP2, suPAR and GDF-15) were analyzed by means of ELISA in patients with stable coronary artery disease (CAD) undergoing four weeks of high- and moderate-intensity training (EXCITE Trial) and in patients with one or more cardiovascular risk factors undergoing eight months of intensive physical exercise (IGF-BP2). Plasma levels of sST2 in patients undergoing eight months of intensive exercise have been published previously by our study group (1.13-fold change, P=0.045).

RESULTS

Four weeks of high-intensity exercise training resulted in a statistically significant change in the plasma level of sST2 (1.106-fold change, P=0.0054) and IGF-BP2 (1.24-fold-change, P=0.0165). Eight months of intensive exercise resulted in a significant increase of IGF-BP2 (median 61.2 ng/mL to 80.7 ng/mL, 1.319-fold change, P=0.006).

CONCLUSIONS

The significant increase of sST2 after four weeks might be a short-term effect due to the mechanical strain caused by the high-intensity training program, whereas the increase in IGF-BP2 after four weeks and eight months is likely a result of metabolic changes due to physical exercise.

Expression of the Novel Cardiac Biomarkers sST2, GDF-15, suPAR, and H-FABP in HFpEF Patients Compared to ICM, DCM, and Controls

Background: Heart failure with preserved ejection fraction (HFpEF) remains an ongoing therapeutic and diagnostic challenge to date. In this study we aimed for an analysis of the diagnostic potential of four novel cardiovascular biomarkers, GDF-15, H-FABP, sST2, and suPAR in HFpEF patients compared to controls as well as ICM, and DCM. Methods: In total, we included 252 stable outpatients and controls (77 DCM, 62 ICM, 18 HFpEF, and 95 controls) in the present study. All patients were in a non-decompensated state and on a stable treatment regimen. Serum samples were obtained and analyzed for GDF-15 (inflammation, remodeling), H-FABP (ischemia and subclinical ischemia), sST2 (inflammation, remodeling) and suPAR (inflammation, remodeling) by means of ELISA. Results: A significant elevation of GDF-15 was found for all heart failure entities compared to controls (p < 0.005). Similarly, H-FABP evidenced a significant elevation in all heart failure entities compared to the control group (p < 0.0001). Levels of sST2 were significantly elevated in ICM and DCM patients compared to the control group and HFpEF patients (p < 0.0001). Regarding suPAR, a significant elevation in ICM and DCM patients compared to the control group (p < 0.0001) and HFpEF patients (p < 0.01) was observed. An AUC analysis identified H-FABP (0.792, 95% CI 0.713–0.870) and GDF-15 (0.787, 95% CI 0.696–0.878) as paramount diagnostic biomarkers for HFpEF patients. Conclusion: Based on their differences in secretion patterns, novel cardiovascular biomarkers might represent a promising diagnostic tool for HFpEF in the future.

Cellular inflammation in pulmonary hypertension: Detailed analysis of lung and right ventricular tissue, circulating immune cells and effects of a dual endothelin receptor antagonist

Growing evidence suggests that inflammation is crucially involved in the pathogenesis of pulmonary hypertension (PH) and consecutive right heart failure. The present study analyzed the inflammatory response in lung and right ventricle in a rat model of PH and evaluated the effects of the dual endothelin receptor antagonist (ERA) Macitentan. PH was induced by monocrotalin (60 mg/kg body weight s.c.) in Sprague-Dawley rats (PH, n = 10) and compared to healthy controls (CON, n = 10) as well as monocrotalin-induced, macitentan-treated rats (THER, n = 10). Detection of Dendritic cells (DCs), regulatory T cells (Tregs) and others as well as RT-PCR based inflammatory gene expression analysis were performed. Circulating DCs and Tregs were quantified by flow cytometry in the rat model and in PH patients (n = 70) compared to controls (n = 52). Inflammatory cells were increased in lung and right ventricular tissue, whereas DCs and Tregs were decreased in blood. Expression of 17 genes in the lung and 20 genes in the right ventricle were relevantly (>2.0 fold) regulated in the PH group. These effects were, at least in part, attenuated in response to Macitentan treatment. In humans as well as rats, immune cells showed significant correlations to clinical, echocardiographic, and haemodynamic parameters. PH is accompanied by a distinct inflammatory response in lung and right but not left ventricular tissue attenuated by Macitentan. Correlations of circulating DCs as well as tissue resident immune cells with parameters reflecting right ventricular function raise the idea of both, promising biomarkers and novel treatment strategies.

Novel Biomarkers in Patients with Chronic Kidney Disease: An Analysis of Patients Enrolled in the GCKD-Study

Background: Chronic kidney disease (CKD) and cardiovascular diseases (CVD) often occur concomitantly, and CKD is a major risk factor for cardiovascular mortality. Since some of the most commonly used biomarkers in CVD are permanently elevated in patients with CKD, novel biomarkers are warranted for clinical practice. Methods: Plasma concentrations of five cardiovascular biomarkers (soluble suppression of tumorigenicity (sST2), growth differentiation factor 15 (GDF-15), heart-type fatty acid-binding protein (H-FABP), insulin-like growth factor-binding protein 2 (IGF-BP2), and soluble urokinase plasminogen activator receptor) were analyzed by means of enzyme-linked immunosorbent assay (ELISA) in 219 patients with CKD enrolled in the German Chronic Kidney Disease (GCKD) study. Results: Except for sST2, all of the investigated biomarkers were significantly elevated in patients with CKD (2.0- to 4.4-fold increase in advanced CKD (estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m² body surface area (BSA)) and showed a significant inverse correlation with eGFR. Moreover, all but H-FABP and sST2 were additionally elevated in patients with micro- and macro-albuminuria. Conclusions: Based on our findings, sST2 appears to be the biomarker whose diagnostic performance is least affected by decreased renal function, thus suggesting potential viability in the management of patients with CVD and concomitant CKD. The predictive potential of sST2 remains to be proven in endpoint studies.

Emerging trends in cardiovascular research: HFpEF in the spotlight. A bibliometric analysis of the years 2009-2016

INTRODUCTION

Up to 50% of patients suffering from acute decompensated heart failure show normal or slightly reduced left ventricular ejection fraction (LVEF). This syndrome, which is known as heart failure with preserved ejection fraction (HFpEF) is associated with increasing age. Epidemiological studies could portrait an increasing importance and an even emerging prevalence in the past decades. Still, there is currently no evidenced based medical treatment option available. Our aims were to identify upcoming trends and emerging concepts and to point out important centers in the global research of HFpEF.

EVIDENCE ACQUISITION

We performed a bibliometric study on current science in the field of HFpEF to identify study characteristics, impact factors and the countries of origin of basic and clinical studies that were published within the years 2009 to 2016. We further prepared density equalizing maps for visualization of the obtained data.

EVIDENCE SYNTHESIS

A total of 5413 studies was screened, of which 794 were found eligible. The scientific output in clinical studies rose from 25 in 2009 to 165 in 2016. Most of the publications had a clinical topic, followed by studies on new imaging techniques. Basic research trials were by far beyond. The USA, Japan and Germany were identified as the most important national contributors to global scientific output.

CONCLUSIONS

This first bibliometric study in the field of HFpEF shows a substantial increase of research within the last decade, mainly in the USA, Japan, and continental Europe. As an ongoing therapeutic trend in this field, we identified RAAS-blockade and 5-phosphodiesterase-inhibition.

Acute right heart failure: future perspective with the PERKAT RV pulsatile right ventricular support device

Acute right heart failure is associated with impaired prognosis in cardiogenic shock. Since most pharmacological therapies are not evaluated for the failing right ventricle, or even contraindicated, there is a need for rapid minimal invasive circulatory right heart support. The PERKAT RV is such a device for acute therapy in congestive heart failure. It reduces the central venous pooling by pumping blood from the inferior vena cava into the pulmonary artery with flow rates of up to 4 litres/min. The device was evaluated in an animal model of acute pulmonary embolism after careful in vitro tests. PERKAT RV increased cardiac output by 59% in sheep suffering from acute right heart failure. We await the first human implantation in the near future. Based on the PERKAT concept, future devolvement will also focus on left heart support.

P1746Prehospital logistics and therapy delays in urban vs. rural regions: implications for quality of acute ST-elevation myocardial infarction care

Background

Treatment and time goals for STEMI care are clearly defined in national and international guidelines. However, initiation of therapy relies in accurate diagnosis after first medical contact (FMC). Prehospital logistics with fast transfer to the next available 24/7 PCI-center can be challenging, especially in rural areas and for transfers across state-borders in Germany.

Objective

To analyze quality of STEMI care in a high volume PCI center serving a city and a large rural area with focus on EMS (emergency medical service) logistics. Two groups of patients admitted by EMS: (1) direct PCI-center admission vs. (2) secondary admission after transfer from a non-PCI hospital were compared.

Methods

Various administrative, procedural, therapeutic and clinical parameters were registered for each patient including timelines of acute treatment (tables). Inaccurate treatment delays were calculated as cumulative time in any prolongation in timely diagnosis or therapy after FMC.

Results

From 340 consecutive STEMI patients in or registry, 299 patients were transferred by EMS. Reperfusion therapy with PPCI was significantly delayed and required double of the time in patients secondary transferred from a non-PCI hospital (Contact-to-Balloon: 195.6±134.8 min vs. 99.6±45.3 min, p<0.001, table 1). An inaccurate delay in timely treatment (delay in correct diagnosis or deferred therapy) was determined in 45% of the patients transferred from non-PCI hospitals vs 26% of directly admitted patients (p=0.02, table 1). Accordingly, correct STEMI diagnosis was established by EMS physician prehospital only in 7.1% in the transfer group vs. 61.9% in the direct admission group (p<0.001, table 1). Our data suggest different reasons for STEMI patients falsely transferred to non-PCI hospitals: a) lower qualification of EMS personnel with ECG misinterpretation and/or false working diagnosis, b) inadequate prehospital logistics with transfer of patients to the next near-by hospital instead of next PCI-center, c) personal or system “thresholds” of EMS physicians in rural areas preventing a direct transfer to PCI-centers. Further analysis of the transfer group (table 2) showed even longer treatment times for patients transferred across state borders compared to transfers within a state (C2B: 264.8±142.2 vs. 143.7±107.0 min, p<0.05, table 2). Importantly, transfers across state borders were not associated with a longer absolute distance (km) to PCI center. However, a rescue helicopter was used for across-state transfers in one third of the cases.

Conclusion

Quality of acute STEMI care is significantly worse in rural areas predominantly due to suboptimal prehospital logistics and poor prehospital emergency care. Our data underline the importance to establish local STEMI networks irrespective of state borders with clearly defined prehospital transfer strategies, continuous medial education of EMS personnel and assessement of local quality of care.

P6287Analysis of novel cardiac markers sST2 and IL-33 in chronic heart failure with reduced ejection fraction

Background

Soluble (s) ST-2 has been recently evaluated as a monitoring parameter in heart failure (HF). Besides being a marker for cardiac strain and hemodynamic stress, studies also found an influence of ST2 on the immune system, above all mediated through its Janus-Face ligand IL-33, an alarmin released under stress conditions or by cellular death. In contrast to sST2, the role of IL-33 in HF is yet unknown.

Objective

In this project, we aimed for an analysis of the ST2/IL33 pathway in patients with heart failure with reduced ejection fraction (HFrEF).

Methods

In total, 200 patients were included in the study: 59 with ischemic (ICM), 65 with dilated (DCM) cardiomyopathy (mean LVEF 38%), as well as 76 control patients without coronary artery disease or signs of heart failure. Serum samples were analyzed by use of ELISA after informed consent.

Results

sST2 showed a significant elevation in all HF patients (p<0.0001) compared to the control group. No significant differences in levels of sST2 were observed between ICM and DCM patients. In contrast to sST2, no differences between HF patients and control group were observed for IL-33. Furthermore, sST2 showed a significant correlation with CRP (p<0.001, r=0.28), NT-pro-BNP (p<0.0001, r=0.40) and an inverse correlation with ejection fraction (p<0.0001, r=−0.40). Additionally, sST2 showed a significant elevation in patients in NYHA stages I-II (p=0.030) and NYHA stages III-IV (p<0.01). Again, no significant correlations were observed between IL-33 and parameters mentioned above.

Analysis of sST2 in heart failure

Conclusions

We observed a significant increase and correlation with disease severity of sST2 in chronic HFrEF patients of both ischemic and non-ischemic origin, but contrary to our expectations, no significant changes in serum levels of IL-33. Thus, a mechanism independent of ST2/IL33 axis could be responsible of sST2 secretion in HF. Further studies including acute decompensated patients could provide a better understanding of the IL-33 role in HF.

Impact of concomitant mitral regurgitation on transvalvular gradient and flow in severe aortic stenosis: a systematic ex vivo analysis of a subentity of low-flow low-gradient aortic stenosis

AIMS

Evaluation of aortic stenosis (AS) is based on echocardiographic measurement of mean pressure gradient (MPG), flow velocity (Vmax) and aortic valve area (AVA). The objective of the present study was to analyse the impact of systemic haemodynamic variables and concomitant mitral regurgitation (MR) on aortic MPG, Vmax and AVA in severe AS.

METHODS AND RESULTS

A pulsatile circulatory model was designed to study function and interdependence of stenotic aortic (AVA: 1.0 cm², 0.8 cm² and 0.6 cm²) and insufficient mitral prosthetic valves (n=8; effective regurgitant orifice area [EROA] <0.2 cm² vs. >0.4 cm²) using Doppler ultrasound. In the absence of severe MR, a stepwise increase of stroke volume (SV) and a decrease of AVA was associated with a proportional increase of aortic MPG. When MR with EROA <0.2 cm² vs. >0.4 cm² was introduced, forward SV decreased significantly (70.9±1.1 ml vs. 60.8±1.6 ml vs. 47.4±1.1 ml; p=0.02) while MR volume increased proportionally. This was associated with a subsequent reduction of aortic MPG (57.1±9.4 mmHg vs. 48.6±13.8 mmHg vs. 33.64±9.5 mmHg; p=0.035) and Vmax (5.09±0.4 m/s vs. 4.91±0.73 m/s vs. 3.75±0.57 m/s; p=0.007). Calculated AVA remained unchanged (without MR: AVA=0.53±0.04 cm² vs. with MR: AVA=0.52±0.05 cm²; p=ns). In the setting of severe AS without MR, changes of vascular resistance (SVR) and compliance (C) did not impact on aortic MPG (low SVR and C: 66±13.8 mmHg and 61.1±20 mmHg vs. high SVR and C: 60.9±9.2 mmHg and 71.5±13.5 mmHg; p=ns) In concomitant severe MR, aortic MPG and Vmax were not significantly reduced by increased SVR (36.6±2.2 mmHg vs. 34.9±5.6 mmHg, p=0.608; 3.89±0.18 m/s vs. 3.96±0.28 m/s; p=ns).

CONCLUSIONS

Systemic haemodynamic variables and concomitant MR may potentially affect diagnostic accuracy of echocardiographic AS evaluation. As demonstrated in the present study, MPG and Vmax are flow-dependent and significantly reduced by a reduction of forward SV from concomitant severe MR, resulting in another entity of low-flow low-gradient aortic stenosis. In contrast, calculated AVA appears to be a robust parameter of AS evaluation if severe MR is present. Changes of SVR and C did not affect the diagnostic accuracy of AS evaluation.

Clinical implications of fetuin-A

Fetuin-A, also termed alpha2-Heremans-Schmid glycoprotein, is a 46kDa hepatocyte derived protein (hepatokine) and serves multifaceted functions.

Transcatheter aortic valve replacement for pure aortic valve regurgitation: "on-label" versus "off-label" use of TAVR devices

INTRODUCTION

Transcatheter aortic valve replacement (TAVR) has become the mainstay of treatment for aortic stenosis in patients with high surgical risk. Pure aortic regurgitation (PAR) is considered a relative contraindication for TAVR; however, TAVR is increasingly performed in PAR patients with unfavorable risk profile. Herein, we aim to summarize available data on TAVR for PAR with special emphasis on "on-label" versus "off-label" TAVR devices.

METHODS AND RESULTS

Pubmed was searched for studies of patients undergoing TAVR for PAR. Primary outcome was 30 day-mortality. Pooled estimated event rates were calculated. Twelve studies including a total of 640 patients were identified until December 2017. Among these, 208 (33%) patients were treated with devices with CE-mark approval for PAR ("on-label"; JenaValve and J valve). Overall, the procedural success rate was 89.9% (95% CI 81.1-96.1%; I² 80%). Major bleeding was reported in 6.4% (95% CI 2.9-10.8%; I² 48%). All-cause mortality at 30 days was 10.4% (95% CI 7.1-14.2%; I² 20%). Stroke occurred in 2.2% (95% CI 0.9-3.9%; I² 0%). A permanent pacemaker was required in 10.7% (95% CI 7.3-14.6%; I² 23%). At 30 days after TAVR, ≥ moderate AR post-interventional was observed in 11.5% (95% CI 2.9-23.6%; I² 90%). In the "on-label"-group, success rate was 93.0% (95% CI 85.9-98.1%; I² 52%). 30-day-mortality was 9.1% (95% CI 3.7-16.0%; I² 36%). More than trace AR was present in 2.8% (95% CI 0.1-7.6%; I² 0%). Compared to first-generation devices, second-generation devices were associated with significantly lower 30-day-mortality (r = - 0.10; p = 0.02), and significantly higher procedural success rates (r = 0.28; p < 0.001). Compared to other second-generation devices, the use of J valve or JenaValve was not associated with altered mortality (r = 0.04; p = 0.50), rates of > trace residual AR (r = - 0.05; p = 0.65) but with a significantly higher procedural success (r = 0.15; p = 0.042).

CONCLUSION

Based on this summary of available observational data TAVR for PAR is feasible and safe in patients deemed inoperable. First-generation TAVR devices are associated with inferior outcome and should be avoided. The "on-label" use of PAR-certified TAVR devices is associated with a significantly higher procedural success rate and might be favorable compared to other second-generation devices.

Concept, Evaluation, and Future Perspectives of PERKAT® RV-A Novel Right Ventricular Assist Device

Right heart failure (RHF) is a life-threatening condition. Mechanical right heart support offers an option for critically ill patients. The PERKAT® RV device is designed for percutaneous implantation in acute RHF. It consists of a nitinol chamber covered by foils containing inflow valves. An outlet tube is attached to its distal tip. Using an 18F sheath, it is implanted in the inferior vena cava while the tube bypasses the right heart with its tip in the pulmonary trunk. Then, an IABP balloon is inserted in the pump chamber. Balloon deflation generates blood inflow into the chamber; during inflation, blood is pumped into the pulmonary arteries. The device is capable of achieving flow rates of up to 3.5 l/min under in vitro conditions. In vivo, we were able to increase cardiac output by 59% in a sheep model of acute pulmonary embolism. Based on this, our further research will focus on first-in-human implants.

Correction to: Transcatheter valve-in-valve implantation (VinV-TAVR) for failed surgical aortic bioprosthetic valves

Unfortunately, an error occurred in the original article.

Multi-biomarker analysis in patients after transcatheter aortic valve implantation (TAVI)

BACKGROUND

In this study we sought to examine whether transcatheter aortic valve implantation (TAVI) is followed by a change in the plasma levels of novel cardiovascular biomarkers.

METHODS

We collected blood samples of 79 patients with severe aortic valve stenosis undergoing TAVI before and at 7 days, 1 month, 3 months and 6 months post TAVI and analyzed the plasma concentrations of GDF-15, H-FABP, fetuin-A, galectin 3, sST2 and suPAR by means of ELISA.

RESULTS

There was a significant increase in the concentration of fetuin-A (median: 52.44 mg/ml to 113.2 mg/ml, p < 0.001) and a significant decrease of H-FABP after TAVI (median: 4.835 ng/ml to 2.534 ng/ml, p < 0.001). The concentrations of suPAR and sST2 showed an initial increase (suPAR median: 2755 pg/ml 3489 pg/ml, p < 0.001; sST2 median: 5832 pg/ml to 7137 pq/ml, p < 0.001) and subsequently decreased significantly.

CONCLUSION

We hypothesize that the decrease of H-FABP and the increase of fetuin-A could be due to a hemodynamic improvement after valve replacement. The initial increase of suPAR could indicate an inflammatory stimulus and the significant increase in sST2 could be due to the mechanical strain caused by implantation of the valve.

Tricuspid Regurgitation - Medical Management and Evolving Interventional Concepts

Severe tricuspid regurgitation (TR) is a complex condition of the right ventricle (RV) and tricuspid valve apparatus and is frequently associated with symptomatic heart failure and a significant morbidity and mortality. In these patients, left heart pathologies lead to chronic pressure overload of the RV, eventually causing progressive RV dilatation and functional TR. Therefore, TR cannot be considered as isolated heart valve disease pathology but has to be understood and treated as one component of a complex structural RV pathology and is frequently also a marker of an advanced stage of cardiac disease. In these patients, medical therapy restricted to diuretics and heart failure medication is frequently ineffective. Also, severe TR in the setting of advanced heart failure constitutes a high risk for cardiac surgery. Neither one of these treatment options has demonstrated a beneficial effect on long-term prognosis. The recent innovations in transcatheter technology led to efforts to develop interventional approaches to severe TR. Multiple innovative treatment concepts are currently under preclinical and clinical investigation to replace or repair TV function. However, up to date none of these approaches is established and there is still a lack of clinical data to support the efficacy of transcatheter TR treatment.

Analysis of novel cardiovascular biomarkers in patients with peripheral artery disease

BACKGROUND

Peripheral artery disease (PAD) is a common form of manifestation of atherosclerosis. PAD has a considerable impact on morbidity, hospitalization rates and health-care costs. Biomarkers have been introduced in many cardiovascular disease entities over the last years. However, an analysis on the correlation of biomarker levels and PAD is still lacking.

METHODS

A total of 106 patients were enrolled in this current study, 51 that were diagnosed with PAD and 55 with excluded coronary and peripheral artery disease as controls. During outpatient visits, plasma samples of all patients were obtained and analyzed for sST2 (hemodynamics and inflammation), galectin-3 (fibrosis and remodeling), GDF-15 (remodeling and inflammation), suPAR (inflammation), and fetuin-A (vascular calcification) by use of ELISA after informed consent.

RESULTS

Compared with controls, patients with PAD showed significantly higher levels of sST2 (5248 vs. 7503 pg/mL, P<0.001), suPAR (2267 vs. 2414 pg/mL, P=0.02), galectin-3 (2795 vs. 4494 pg/mL, P<0.001), and GDF-15 (549 vs. 767 pg/mL, P<0.001). Fetuin-A showed a trend towards lower levels in patients with PAD (117 vs. 100 ng/mL, P=0.119).

CONCLUSIONS

Circulating levels of sST2, suPAR, galectin-3, and GDF-15 were significantly elevated in PAD patients. In contrast, fetuin-A levels showed a decrease in PAD patients indicating increased vascular calcification. Thus, by incorporating different pathophysiological processes present in PAD, tested novel biomarkers facilitate a more precise diagnosis as well as a more accurate evaluation of disease severity and progression.

PERKAT RV: first in vivo data of a novel right heart assist device

AIMS

Mechanical right ventricular (RV) support offers a treatment option for critically ill patients with RV failure (RVF). We developed an assist device for rapid percutaneous implantation. The aim of the present study was to investigate the implantation procedure, haemodynamic performance and possible side effects of the novel right ventricular assist device - PERKAT RV - in an animal model.

METHODS AND RESULTS

The PERkutane KATheterpumptechnologie RV (PERKAT RV) device consists of a nitinol chamber covered by foil containing inflow valves. An outlet tube is attached to its distal part. The system is designed for 18 Fr percutaneous implantation. The chamber is unfolded in the inferior vena cava while the outlet tube bypasses the right heart with the tip in the pulmonary trunk. An IABP balloon is placed inside. Balloon deflation generates blood flow into the chamber; during inflation, blood is guided into the pulmonary arteries. Acute RVF was induced by venous injection of Sephadex in seven sheep for evaluation of the device. The PERKAT RV was able to improve haemodynamics immediately generating a median increase in cardiac output of 59%. Longer pump support was evaluated in a second study. Four sheep were supported for eight hours without any problems.

CONCLUSIONS

The percutaneous implantation and explantation of the PERKAT RV device was possible in the designed way. The sheep studies proved beneficial haemodynamic effects in acute RVF. The system offers easy and safe treatment in acute RVF.

Increased Number of Mast Cells in Atherosclerotic Lesions Correlates with the Presence of Myeloid but not Plasmacytoid Dendritic Cells as well as Pro-inflammatory T Cells

BACKGROUND

Atherosclerosis is an inflammatory disease of the vessel wall promoted by different immune cells and inflammatory mediators.

METHODS

In this study, 26 human plaques and 12 control vessels without atherosclerosis were immunohistochemically stained to analyze the emergence of mast cells dependent on plaque morphology and to correlate mast cell occurrence with the emergence of myeloid as well as plasmacytoid dendritic cells. Also, mast cell emergence was correlated with the number of pro-inflammatory T cells. For this, plaques were classified as stable or unstable according to established histological criteria.

RESULTS

As expected, atherosclerotic lesions showed significantly higher numbers of tryptase+, chymase+, and cathepsin G+ mast cells compared to control vessels, particularly in lesions with unstable morphology. As a novel finding, we detected significant correlations between mast cells and myeloid dendritic cells (fascin, CD83, r > 0.3, p < 0.01), but not plasmacytoid dendritic cells (CD123, CD304). Also, we observed significant correlations of mast cells and different subgroups of pro-inflammatory T cells (CD3, CD8, CD161, CD25; r > 0.35, p < 0.05).

CONCLUSIONS

Overall, the higher number of mast cells in plaques, particularly with unstable morphology, suggests that mast cells might be involved in the progression of atherosclerosis. The correlation of mast cells with other immune cells that are pivotal in atherogenesis, e.g., myeloid dendritic cells and pro-inflammatory T cells, also suggests an interplay leading to plaque destabilization. Therefore, modulating local mast cell function and invasion into the plaque might be a therapeutic tool for plaque stabilization.

Increased Serum Levels of Fetal Tenascin-C Variants in Patients with Pulmonary Hypertension: Novel Biomarkers Reflecting Vascular Remodeling and Right Ventricular Dysfunction?

Pulmonary vascular remodeling is a pathophysiological feature that common to all classes of pulmonary hypertension (PH) and right ventricular dysfunction, which is the major prognosis-limiting factor. Vascular, as well as cardiac tissue remodeling are associated with a re-expression of fetal variants of cellular adhesion proteins, including tenascin-C (Tn-C). We analyzed circulating levels of the fetal Tn-C splicing variants B⁺ and C⁺ Tn-C in serum of PH patients to evaluate their potential as novel biomarkers reflecting vascular remodeling and right ventricular dysfunction. Serum concentrations of B⁺ and C⁺ Tn-C were determined in 80 PH patients and were compared to 40 healthy controls by enzyme-linked immunosorbent assay. Clinical, laboratory, echocardiographic, and functional data were correlated with Tn-C levels. Serum concentrations of both Tn-C variants were significantly elevated in patients with PH (p < 0.05). Significant correlations could be observed between Tn-C and echocardiographic parameters, including systolic pulmonary artery pressure (B⁺ Tn-C: r = 0.31, p < 0.001, C⁺ Tn-C: r = 0.26, p = 0.006) and right atrial area (B⁺ Tn-C: r = 0.46, p < 0.001, C⁺ Tn-C: r = 0.49, p < 0.001), and laboratory values like BNP (B⁺ Tn-C: r = 0.45, p < 0.001, C⁺ Tn-C: r = 0.42, p < 0.001). An inverse correlation was observed between Tn-C variants and 6-minute walk distance as a functional parameter (B⁺ Tn-C: r = -0.54, p < 0.001, C⁺ Tn-C: r = -0.43, p < 0.001). In a multivariate analysis, B⁺ Tn-C, but not C⁺ Tn-C, was found to be an independent predictor of pulmonary hypertension. Both fetal Tn-C variants may represent novel biomarkers that are capable of estimating both pulmonary vascular remodeling and right ventricular load. The potential beneficial impact of Tn-C variants for risk stratification in patients with PH needs further investigation.

Elevated plasma levels of interleukin-16 in patients with acute myocardial infarction

Interleukin (IL)-16, a polypeptide cytokine, plays a crucial role in the inflammatory process, acting as a chemoattractant for peripheral immune cells and has been linked to various inflammatory diseases. However, its role in patients with acute myocardial infarction (AMI) is unclear.We retrospectively analyzed serum levels of IL-16 in blood of patients with (STEMI, n = 45) and without ST-segment elevation myocardial infarction (NSTEMI, n = 42) compared with controls with excluded coronary artery disease (n = 55). Furthermore, correlation analysis with inflammatory cells, C-reactive protein (CRP) levels, dendritic cell precursors (DCPs), and other clinical and biochemical markers was performed.Compared with controls, patients with STEMI and NSTEMI evidenced higher levels of IL-16 in pg/mL (STEMI: 759.38 ± 471.54, NSTEMI: 677.77 ± 438.8, control: 500.45 ± 432.21; P = .002). IL-16 correlated with CRP (r = 0.26, P = .001), leucocytes (r = 0.38, P < .001), NT-proBNP (r = 0.20, P = .02) and hsTnT (r = 0.25, P = .004). Circulating myeloid DCPs, plasmacytoid DCPs, and total DCPs showed a significant inverse correlation to IL-16 levels (r = -0.21, P = .01; r = -0.23, P = .005; r = -0.26, P = .002, respectively).Interleukin-16 might play an important role in the inflammatory process of patients suffering from AMI and correlates with inflammatory cell activation and clinical and biochemical markers. The cytokine IL-16 might upregulate the proinflammatory response and recruitment of inflammatory cells into infarcted myocardium.