Pro-substance p for evaluation of risk in acute myocardial infarction

Association of hypertension burden with stroke risk in patients with heart failure with preserved ejection fraction

Introduction

Whether the hypertension burden is associated with stroke incidence is inconclusive. In this study, we aimed to investigate the relationship between hypertension burden and stroke risk in patients with heart failure with preserved ejection fraction (HFpEF).

Methods

HFpEF patients from the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial were divided into three groups (low, medium, and high risk) according to their hypertension burden values. Higher hypertension burden risk represented the longer duration of hypertension. We evaluated the association of hypertension burden with stroke risk using Fine and Gray's competing risk models.

Results

A total of 3431 HFpEF patients (mean age: 68.5 ± 9.58 years, 51.6% females) were enrolled. During a median follow-up of 3.3 years, per 10-point increase in hypertension burden was associated with any stroke (hazard ratio [HR] 1.15, 95% confidence interval [CI] 1.08-1.21), new-onset stroke (HR 1.14, 95% CI 1.07-1.21), and ischemic stroke (HR 1.10, 95% CI 1.02-1.17). When hypertension burden was analyzed as a categorical variable, any stroke risk was increased in the medium- (HR 1.59, 95% CI 1.01-2.40) and high-risk (HR 3.19, 95% CI 2.05-4.97) groups when compared with the low-risk group. For the outcomes of new-onset (HR 2.92, 95% CI 1.80-4.74) and ischemic stroke (HR 2.46, 95% CI 1.41-4.29), similar results were observed in patients with high-versus low-risk hypertension burden.

Conclusions

Increasing hypertension burden was associated with an increased risk of stroke, suggesting that shortening hypertension duration might appropriately minimize the stroke incidence in HFpEF patients.

Cathepsin S Levels and Survival Among Patients With Non-ST-Segment Elevation Acute Coronary Syndromes

BACKGROUND

Patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS) are at high residual risk for long-term cardiovascular (CV) mortality. Cathepsin S (CTSS) is a lysosomal cysteine protease with elastolytic and collagenolytic activity that has been involved in atherosclerotic plaque rupture.

OBJECTIVES

The purpose of this study was to determine the following: 1) the prognostic value of circulating CTSS measured at patient admission for long-term mortality in NSTE-ACS; and 2) its additive value over the GRACE (Global Registry of Acute Coronary Events) risk score.

METHODS

This was a single-center cohort study, consecutively recruiting patients with adjudicated NSTE-ACS (n = 1,112) from the emergency department of an academic hospital. CTSS was measured in serum using enzyme-linked immunosorbent assay. All-cause mortality at 8 years was the primary endpoint. CV death was the secondary endpoint.

RESULTS

In total, 367 (33.0%) deaths were recorded. CTSS was associated with increased risk of all-cause mortality (HR for highest vs lowest quarter of CTSS: 1.89; 95% CI: 1.34-2.66; P < 0.001) and CV death (HR: 2.58; 95% CI: 1.15-5.77; P = 0.021) after adjusting for traditional CV risk factors, high-sensitivity C-reactive protein, left ventricular ejection fraction, high-sensitivity troponin-T, revascularization and index diagnosis (unstable angina/ non-ST-segment elevation myocardial infarction). When CTSS was added to the GRACE score, it conferred significant discrimination and reclassification value for all-cause mortality (Delta Harrell's C: 0.03; 95% CI: 0.012-0.047; P = 0.001; and net reclassification improvement = 0.202; P = 0.003) and CV death (AUC: 0.056; 95% CI: 0.017-0.095; P = 0.005; and net reclassification improvement = 0.390; P = 0.001) even after additionally considering high-sensitivity troponin-T and left ventricular ejection fraction.

CONCLUSIONS

Circulating CTSS is a predictor of long-term mortality and improves risk stratification of patients with NSTE-ACS over the GRACE score.

Combined Assessment of D-Dimer with the Get with the Guidelines-Heart Failure Risk Score and N-Terminal Pro-B-Type Natriuretic Peptide in Patients with Acute Decompensated Heart Failure with Preserved and Reduced Ejection Fraction

The prognostic role of D-dimer in different types of heart failure (HF) is poorly understood. We investigated the prognostic value of D-dimer on admission, both independently and in combination with the Get With The Guidelines—Heart Failure (GWTG-HF) risk score and N-terminal pro-B-type natriuretic peptide (NT-proBNP), in patients with preserved left ventricular ejection fraction (LVEF) and acute decompensated HF (HFpEF) or reduced LVEF (HFrEF). Baseline D-dimer levels were measured on admission in 1670 patients (mean age: 75 years) who were hospitalized for worsening HF. Of those patients, 586 (35%) were categorized as HFpEF (LVEF ≥ 50%) and 1084 as HFrEF (LVEF < 50%). During the 12-month follow-up period after admission, 360 patients died. Elevated levels (at least the highest tertile value) of D-dimer, GWTG-HF risk score, and NT-proBNP were all independently associated with mortality in all HFpEF and HFrEF patients (all p < 0.05). Adding D-dimer to a baseline model with a GWTG-HF risk score and NT-proBNP improved the net reclassification and integrated discrimination improvement for mortality greater than the baseline model alone in all populations (all p < 0.001). The number of elevations in D-dimer, GWTG-HF risk score, and NT-proBNP were independently associated with a higher risk of mortality in all study populations (HFpEF and HFrEF patients; all p < 0.001). The combination of D-dimer, which is independently predictive of mortality, with the GWTG-HF risk score and NT-proBNP could improve early prediction of 12-month mortality in patients with acute decompensated HF, regardless of the HF phenotype.

Neprilysin inhibition does not alter dynamic of proenkephalin-A 119-159 and pro-substance P in heart failure

AIMS

As NEP degrades many substrates, the specific therapeutic mechanism of NEP inhibition with angiotensin receptor neprilysin inhibitor (ARNi) in heart failure with reduced ejection fraction (HFrEF) is not entirely evident. The aim of this study was to investigate the response of two substrates of NEP-the tachykinin and enkephalin systems-to the initiation of ARNi therapy in HFrEF.

METHODS AND RESULTS

Between 2016 and 2018, 141 consecutive patients with stable HFrEF [74 with initiation of ARNi and 67 controls on continuous angiotensin converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) therapy] were prospectively enrolled. Plasma proenkephalin-A 119-159 (PENK) and pro-substance P (pro-SP) were serially determined. Proenkephalin-A 119-159 and pro-SP correlated strongly with each other (r_s  = 0.67, P < 0.001) and kidney function (r_s  = -0.66, P < 0.001 and r_s  = -0.54, P < 0.001) and modestly with NT-proBNP (r_s  = 0.32, P < 0.001 and r_s  = 0.24, P = 0.006, respectively). Concentrations of circulating PENK were slightly elevated after 1 and 2 year follow-up compared with baseline (BL) [BL median: 67.4 pmol/L (IQR: 57.3-89.8), 1 year: 83.5 pmol/L (IQR: 62.4-111.6), 2 years: 92.3 pmol/L (IQR: 63.1-101.9); BL vs. 1 year: P = 0.017 and BL vs. 2 years: P = 0.019] in the overall analysis, but lost significance at 2 year follow-up when assessed in paired subanalysis (P = 0.116). Plasma pro-SP levels remained comparable during the entire follow-up [BL median: 78.3 pmol/L (IQR: 67.9-90.6), 1 year: 75.9 pmol/L (IQR: 58.6-96.3), 2 years: 79.7 pmol/L (IQR: 59.9-105.3); P = ns for both timepoints]. Biomarker patterns of ARNi patients were independent from baseline therapy, that is, ACEi or ARB (P > 0.05 between groups).

CONCLUSIONS

Although enkephalins and SP are known substrates of NEP, NEP inhibition by ARNi does not clearly affect the circulating precursors PENK and pro-SP in HFrEF.

Detection of early breast cancer beyond mammographic screening: a promising biomarker panel

Aim: We assessed the suitability of a biomarker panel to improve early detection and individual risk assessment in breast cancer (BC) patients. Materials & methods: PENK, pro-SP, hGH and CA15-3 of 204 BC patients and 68 healthy controls were measured. Results: PENK and human growth hormone concentrations were significantly lower and pro-SP values higher in BC patients compared with controls. C-index increased from 0.628 for CA15-3 alone to 0.754 when all three biomarkers were added to the model. Conclusion: This biomarker panel may improve early detection of BC and influence the assessment of breast imaging. It might be useful for a risk-adapted cancer surveillance or primary prevention program by a more precise determination of an individualized BC risk.

Substance P-mediated cardiac mast cell activation: An in vitro study

The neuropeptide substance P can induce degranulation of cardiac mast cells at high concentrations. Herein, we seek to further understand substance P activation of cardiac mast cells in the context of other neuropeptides as well as modulation by non-neuropeptides. This is important given the increasingly recognized role of both cardiac mast cells and substance P in adverse cardiac remodeling. To address this, we isolated cardiac mast cells and compared their response to substance P as well as other members from the tachykinin family of peptides, including neurokinin A and hemokinin-1. We also tested the ability of other factors to manipulate the cardiac mast cell response to substance P. We found that while neurokinin A did not induce cardiac mast cell degranulation, both substance P and hemokinin-1 induced a concentration-dependent release of histamine; the maximal response to hemokinin-1 was greater than to substance P. Neurokinin-1 receptor blockade prevented substance P-induced histamine release, while only partially attenuating hemokinin-1-induced histamine release. The antioxidant N-acetylcysteine attenuated histamine release in response to hemokinin-1 and had no effect on substance P-induced histamine release. Selective PPAR-γ agonists attenuated histamine release in response to substance P. These data indicate that substance P activates cardiac mast cells via the neurokinin-1 receptor, and that the activation response is different to other tachykinins. That the response to substance P is receptor mediated and can be modulated by activation of other receptors (PPAR-γ), argues that substance P activation of cardiac mast cells has potential biological significance.

The Regulation of Pulmonary Vascular Tone by Neuropeptides and the Implications for Pulmonary Hypertension

Pulmonary hypertension (PH) is an incurable, chronic disease of small pulmonary vessels. Progressive remodeling of the pulmonary vasculature results in increased pulmonary vascular resistance (PVR). This causes secondary right heart failure. PVR is tightly regulated by a range of pulmonary vasodilators and constrictors. Endothelium-derived substances form the basis of most current PH treatments. This is particularly the case for pulmonary arterial hypertension. The major limitation of current treatments is their inability to reverse morphological changes. Thus, there is an unmet need for novel therapies to reduce the morbidity and mortality in PH. Microvessels in the lungs are highly innervated by sensory C fibers. Substance P and calcitonin gene-related peptide (CGRP) are released from C-fiber nerve endings. These neuropeptides can directly regulate vascular tone. Substance P tends to act as a vasoconstrictor in the pulmonary circulation and it increases in the lungs during experimental PH. The receptor for substance P, neurokinin 1 (NK1R), mediates increased pulmonary pressure. Deactivation of NK1R with antagonists, or depletion of substance P prevents PH development. CGRP is a potent pulmonary vasodilator. CGRP receptor antagonists cause elevated pulmonary pressure. Thus, the balance of these peptides is crucial within the pulmonary circulation (Graphical Abstract). Limited progress has been made in understanding their impact on pulmonary pathophysiology. This is an intriguing area of investigation to pursue. It may lead to promising new candidate therapies to combat this fatal disease. This review provides a summary of the current knowledge in this area. It also explores possible future directions for neuropeptides in PH.

Amyloid-β (1-40) and Mortality in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome: A Cohort Study

BACKGROUND

Amyloid-β (1-40) (Aβ40) is implicated in mechanisms related to plaque destabilization and correlates with adverse outcomes in stable coronary artery disease.

OBJECTIVE

To determine the prognostic and reclassification value of baseline circulating levels of Aβ40 after adjustment for the Global Registry of Acute Coronary Events (GRACE) score, which is widely recommended for risk stratification in non-ST-segment elevation acute coronary syndrome (NSTE-ACS).

DESIGN

Retrospective cohort study using data from 2 independent prospective cohorts, the Heidelberg study (n = 1145) and the validation multicenter international APACE (Advantageous Predictors of Acute Coronary Syndrome Evaluation) study (n = 734).

SETTING

Academic hospitals in 7 European countries.

PARTICIPANTS

Patients with adjudicated NSTE-ACS followed for a median of 21.9 and 24.9 months in the Heidelberg and APACE studies, respectively.

MEASUREMENTS

All-cause mortality was the primary end point.

RESULTS

Amyloid-β (1-40) was associated with mortality after multivariate adjustment for age, sex, diabetes mellitus, high-sensitivity cardiac troponin T and C-reactive protein, revascularization, and ACS type (Heidelberg cohort hazard ratio [HR] for 80th vs. 20th percentiles, 1.66 [95% CI, 1.06 to 2.61; P = 0.026]; APACE cohort HR, 1.50 [CI, 1.15 to 1.96; P = 0.003]). It was also associated with mortality after adjustment for the GRACE score (Heidelberg cohort HR for 80th vs. 20th percentiles, 1.11 [CI, 1.04 to 1.18; P = 0.001]; APACE cohort HR, 1.39 [CI, 1.02 to 1.88; P = 0.036]). Amyloid-β (1-40) correctly reclassified risk for death over the GRACE score (net reclassification index, 33.4% and 47.1% for the Heidelberg and APACE cohorts, respectively) (P < 0.05).

LIMITATION

At low concentrations of Aβ40, dose-response associations with mortality differed between cohorts, possibly because of varying blood preparations used to measure Aβ40.

CONCLUSION

Circulating Aβ40 is a predictor of mortality and improves risk stratification of patients with NSTE-ACS over the GRACE score recommended by clinical guidelines. The clinical application of Aβ40 as a novel biomarker in NSTE-ACS should be further explored and validated.

PRIMARY FUNDING SOURCE

German Cardiac Society.

Prognostic value of plasma DPP4 activity in ST-elevation myocardial infarction

Background

Dipeptidyl peptidase-4 (DPP4) regulates blood glucose levels and inflammation, and it is also implicated in the pathophysiological process of myocardial infarction (MI). Plasma DPP4 activity (DPP4a) may provide prognostic information regarding outcomes for ST-segment elevation MI (STEMI) patients.

Methods

Blood samples were obtained from 625 consecutively admitted, percutaneous coronary intervention-treated STEMI patients with a mean age of 57 years old. DPP4a was quantified using enzymatic assays.

Results

The median follow-up period was 30 months. Multivariate Cox-regression analyses (adjusted for confounding variables) showed that a 1 U/L increase of DPP4a did not associate with risks of major adverse cardiac or cerebrovascular events (MACCE), cardiovascular mortality, MI, heart failure readmission, stroke, non-cardiovascular mortality and repeated revascularization. However, in a subset of 149 diabetic STEMI patients, DPP4a associated with an increased risk of MACCE (HR 1.16; 95% CI 1.04–1.30; p = 0.01).

Conclusions

DPP4a did not associate with cardiovascular events and non-cardiovascular mortality in non-diabetic STEMI patients. However, DPP4a may be associated with future MACCE in diabetic STEMI patients.

Trial registration NCT03046576, registered on 5 February, 2017, retrospectively registered

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0553-3) contains supplementary material, which is available to authorized users.

The role of neuropeptides in adverse myocardial remodeling and heart failure

In addition to traditional neurotransmitters of the sympathetic and parasympathetic nervous systems, the heart also contains numerous neuropeptides. These neuropeptides not only modulate the effects of neurotransmitters, but also have independent effects on cardiac function. While in most cases the physiological actions of these neuropeptides are well defined, their contributions to cardiac pathology are less appreciated. Some neuropeptides are cardioprotective, some promote adverse cardiac remodeling and heart failure, and in the case of others their functions are unclear. Some have both cardioprotective and adverse effects depending on the specific cardiac pathology and progression of that pathology. In this review, we briefly describe the actions of several neuropeptides on normal cardiac physiology, before describing in more detail their role in adverse cardiac remodeling and heart failure. It is our goal to bring more focus toward understanding the contribution of neuropeptides to the pathogenesis of heart failure, and to consider them as potential therapeutic targets.

Unacylated ghrelin analog prevents myocardial reperfusion injury independently of permeability transition pore

Reperfusion injury is responsible for an important part of myocardial infarct establishment due notably to triggering cardiomyocytes death at the first minutes of reperfusion. AZP-531 is an optimized analog of unacylated ghrelin currently in clinical development in several metabolic diseases. We investigated a potential cardioprotective effect of AZP-531 in ischemia/reperfusion (IR) and the molecular underlying mechanism(s) involved in this protection. In vivo postconditioning with AZP-531 in C57BL6 mouse IR model decreased infarct size. Western blot analysis on areas at risk from the different mouse groups showed that AZP-531 activates Akt, ERK1-2 as well as S6 and 4EBP1, mTORC1 effectors. We also showed an inhibition of caspase 3 cleavage and Bax translocation to the mitochondria. AZP-531 also stimulated the expression of antioxidants and was capable of decreasing mitochondrial H₂O₂ production, contributing to the reduction of ROS accumulation. AZP-531 exhibits cardioprotective effect when administrated for postconditioning in C57BL6 mouse IR model. Treatment with AZP-531 rescued the myocardium from cell death at early reperfusion by stimulating protein synthesis, inhibiting Bax/caspase 3-induced apoptosis as well as ROS accumulation and oxidative stress-induced necrosis. AZP-531 may prove useful in the treatment of IR injury.

Trimethylamine N-oxide and Risk Stratification after Acute Myocardial Infarction

BACKGROUND

Risk stratification in acute myocardial infarction (MI) remains a clinical challenge. Trimethylamine N-oxide (TMAO), a gut-derived metabolite, was investigated for its ability to assist in risk stratification for acute MI hospitalizations.

METHODS

TMAO was analyzed in 1079 acute MI patients. Associations with adverse outcome of all-cause mortality or reinfarction (death/MI) for shorter (6-month) and longer (2-year) terms were assessed and compared to other cohort-specific biomarkers. Added value in risk stratification by combined use with the Global Registry of Acute Coronary Events (GRACE) score was also investigated.

RESULTS

TMAO independently predicted death/MI at 2 years [292 events, hazard ratio 1.21 (95% CI, 1.03-1.43), P = 0.023], but was not able to predict death/MI at 6 months (161 events, P = 0.119). For death/MI at 2 years, TMAO retained independent prediction of risk (P = 0.034) and improved stratification even after addition of multiple alternative and contemporary biomarkers previously shown to provide added prognostic value in this cohort. From these contemporary biomarkers, TMAO remained the only significant predictor of outcome. Further, TMAO improved risk stratification for death/MI at 6 months by down-classifying risk in patients with GRACE score >119 and plasma TMAO concentration ≤3.7 μmol/L.

CONCLUSIONS

TMAO levels showed association with poor prognosis (death/MI) at 2 years and superiority over contemporary biomarkers for patients hospitalized due to acute MI. Furthermore, when used with the GRACE score for calculating risk at 6 months, TMAO reidentified patients at lower risk after initial categorization into a higher-risk group and showed usefulness as a secondary risk stratification biomarker.

Insertion/Insertion Genotype of Angiotensin I-Converting-Enzyme Gene Predicts Risk of Myocardial Infarction in North East India

Myocardial infarction (MI) is common in India and the disease occurs at a relatively younger age. We wanted to look for association of Angiotensin I-converting enzyme (ACE) gene with MI in North East India. We also wanted to examine possible environmental interaction of ACE gene with established cardiovascular risk factors in causation of MI. In the study carried out in Assam Medical College, 200 consecutive confirmed cases of MI were recruited. Equal numbers of age- and sex-matched control subjects from hospital workers and patients attending the hospital for diseases unrelated to cardiovascular disease were enrolled. Structured questionnaires were used to note demographic and clinical factors. Cardiovascular risk factors were determined from history, physical examination and biochemical investigations. ACE insertion/deletion (I/D) polymorphism was determined by PCR method. Interaction of ACE gene with other risk factors was noted. The study identified ACE II genotype (odds ratio = 3.02; 95% CI 1.40-6.51), smoking, hypertension, diabetes and serum triglyceride > 150 mg/dl as independent risk factors for MI. ACE II genotype showed greater risk in non-smokers, non-hypertensives, non-diabetics and in subjects with LDL-C < 130 mg/dl. Low HDL cholesterol enhanced the genetic risk. Subjects with ACE II genotype have an independent risk of developing MI, specially in low cardiovascular risk subjects.