Multi-omics study reveals that statin therapy is associated with restoration of gut microbiota homeostasis and improvement in outcomes in patients with acute coronary syndrome.

Rationale: Prior chronic treatment with statins has been shown to be associated with more favorable outcomes in patients with acute coronary syndrome (ACS). Specific changes in the gut microbiota and microbial metabolites have been shown to influence the progression of coronary artery disease. However, the critical microbial and metabolomic changes associated with the cardiovascular protective effects of statins in ACS remain elusive. Methods: In the present study, we performed 16S rRNA sequencing and serum metabolomic analysis in 36 ACS patients who had received chronic statin treatment, 67 ACS patients who had not, and 30 healthy volunteers. A follow-up study was conducted. Metagenomic functional prediction of important bacterial taxa was achieved using PICRUSt2. Results: Statins modulated the gut microbiome of ACS patients towards a healthier status, i.e., reducing potentially pathogenic bacteria such as Parabacteroides merdae but increasing beneficial bacteria such as Bifidobacterium longum subsp. longum, Anaerostipes hadrus and Ruminococcus obeum. Moreover, prior chronic statin therapy was associated with improved outcome in ACS patients. Multi-omics analysis revealed that specific changes in bacterial taxa were associated with disease severity or outcomes either directly or by mediating metabolites such as fatty acids and prenol lipids. Finally, we discovered that important taxa associated with statins were correlated with fatty acid- and isoprenoid-related pathways that were predicted by PICRUSt2. Conclusions: Our study suggests that statin treatment might benefit ACS patients by modulating the composition and function of the gut microbiome, which might result in improved circulating metabolites and reduced metabolic risk. Our findings provide new insights for understanding the heterogenic roles of statins in ACS patients through host gut microbiota metabolic interactions.

Comparisons of microbiota-generated metabolites in patients with young and elderly acute coronary syndrome.

OBJECTIVE: Acute coronary syndrome (ACS) is a leading cause of death worldwide. There is great interest in defining the risk factors and underlying mechanisms of ACS among young people. The microbiota and its metabolites have recently become a popular research topic, yet there is still no study that investigated microbiota-generated metabolites as a possible risk factor in young patients with ACS. In this study, we aimed to investigate the relationship between microbiota-generated metabolites and ACS in young people. METHODS: This study included 44 young patients with ACS (<50 years of age), 39 elderly patients with ACS, and 44 patients with normal coronary arteries. Inflammatory parameters and serum trimethylamine N-oxide (TMAO) and choline levels were measured in all patients. RESULTS: Young patients with ACS had significantly higher levels of TMAO and choline compared to the control and elderly ACS groups. Also, elderly patients with ACS had a significantly higher level of TMAO than the control group. Linear regression analysis was performed to determine the independent predictors of TMAO. Two regression models were involved. The first model included young ACS and control groups, while the second model included young and elderly ACS groups. In the first model, we found that young ACS (ß=0.399, p=0.004) and smoking ACS (ß=0.211, p=0.046) were significantly associated with TMAO level. In the second model, young ACS was significantly associated with TMAO level (ß=0.230, p=0.035). CONCLUSION: In this study, we have shown that young ACS was significantly associated with increased TMAO level.

Gut microbial taxa as potential predictive biomarkers for acute coronary syndrome and post-STEMI cardiovascular events.

Plasma trimethylamine N-oxide (TMAO) is associated with coronary atherosclerotic plaque and cardiovascular disease risk, but associations between gut microbes in acute coronary syndrome (ACS) and post-ST-segment elevation myocardial infarction (post-STEMI) events are unknown. We investigated associations between gut microbial taxa and systemic TMAO levels and the possible TMAO contribution to incident post-STEMI cardiovascular events. PATIENTS AND METHODS: A total of 60 patients, including 30 with unstable angina pectoris (UAP), 30 post-STEMI and 30 healthy controls, were enrolled from June to November 2017. Metagenomic sequencing was performed and TMAO and IL-6 were detected. RESULTS: Minimal discriminators of gut microbial taxa (top 40) distinguished ACS patients from controls. Serum TMAO levels were positively associated with increased abundance of Aerococcaceae, Ruminococcaceae_UCG.005, Ruminococcaceae_UCC.014 and X. Eubacterium_fissicatena, and decreased abundance of Lachnospiraceae_FCS020 (P < 0.05). Elevated serum TMAO levels correlated independently with ACS (P < 0.05). Risk stratification for incident major adverse cardiovascular events (MACE) improved at one year in patients with serum TMAO levels ≦2.19 µM. Serum interleukin-6 levels were not significantly increased in patients with ACS and post-STEMI MACE. CONCLUSIONS: ACS and incident post-STEMI MACE may be associated with the gut bacteria choline metabolite TMAO. The specific gut microbial taxa identified in association with serum TMAO levels may be potential predictive biomarkers for accurate diagnosis of ACS onset.

Effect of Helicobacter pylori infection on the risk of acute coronary syndrome: A systematic review and meta-analysis.

BACKGROUND: Numerous studies have illustrated the association between Helicobacter pylori (H pylori) infection and acute coronary syndrome (ACS). However, the results are contradictory. Therefore, we conducted the meta-analysis to identify the association between H pylori and ACS. METHODS: We performed a systematic search through electronic databases (Excerpta Medica Database, PubMed, Cochrane Library, and Web of Science). Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated with a random effect model. We also carried out the sensitivity analysis and publication bias. RESULTS: Forty-four eligible studies involving 7522 cases and 8311 controls were included. The pooled result showed that H pylori infection was associated with an increase risk of ACS (OR = 2.03, 95% CI 1.66-2.47). In addition, similar results were obtained in subgroups of study quality, area, human development index, and H pylori detection method. The OR for developing countries was significantly higher than developed countries (OR = 2.58 vs OR = 1.69). Moreover, H pylori with cytotoxin-associated antigen A was also significantly associated with an increase risk of ACS (OR = 2.39, 95% CI 1.21-4.74). CONCLUSION: The meta-analysis suggested that H pylori infection was associated with an increased risk of ACS, especially in developing countries. H pylori is easily screened and can be treated with a wide range of drugs. Thus, more high-quality and well-designed studies are needed to confirm whether the treatment of H pylori is an effective way to reduce ACS risk.

Immunologic burden links periodontitis to acute coronary syndrome.

BACKGROUND AND AIMS: Periodontitis, a common polymicrobial inflammatory disease in the tooth supporting tissues, is a risk factor for coronary artery disease. One of the proposed underlying mechanisms is the systemic immune response to periodontal infection. We studied how serum antibodies against seven periodontal pathogens and their subgingival levels associate with each other, periodontitis, and coronary artery disease. METHODS: The Parogene cohort included 505 Finnish patients (mean age 63 y) who underwent coronary angiography, and clinical and radiographic oral examinations. Coronary diagnosis was defined as no significant coronary artery disease (<50% stenosis, n = 152), stable coronary artery disease (≥50% stenosis, n = 184) and acute coronary syndrome (n = 169). Levels of subgingival Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Tannerella forsythia, Campylobacter rectus, and Fusobacterium nucleatum were determined by checkerboard DNA-DNA hybridization. Serum antibody (IgA/IgG) levels were analyzed with enzyme-linked immunosorbent assay (ELISA). Aggregate IgA/IgG burdens were calculated by summing and standardizing the serum antibody levels. RESULTS: Patients with active periodontitis were characterized by higher levels of subgingival bacteria and corresponding IgA/IgG response. Quartiles 2-4 of serum IgA/IgG burden indicated higher risk for acute coronary syndrome (OR 1.84, 95%CI 1.01-3.35 for IgA; OR 1.87, 95%CI 1.01-3.46 for IgG) independently of established cardiovascular risk factors, body mass index, number of teeth, subgingival bacterial levels and periodontal diagnosis. CONCLUSIONS: Our findings support the hypothesis that the association between periodontitis and cardiovascular diseases is partly mediated by the immunologic response for periodontal pathogens.

Association of Endodontic Lesions with Coronary Artery Disease.

An endodontic lesion (EL) is a common manifestation of endodontic infection where Porphyromonas endodontalis is frequently encountered. EL may associate with increased risk for coronary artery disease (CAD) via similar pathways as marginal periodontitis. The aim of this cross-sectional study was to delineate the associations between EL and CAD. Subgingival P. endodontalis, its immune response, and serum lipopolysaccharide were examined as potential mediators between these 2 diseases. The Finnish Parogene study consists of 508 patients (mean age, 62 y) who underwent coronary angiography and extensive clinical and radiographic oral examination. The cardiovascular outcomes included no significant CAD ( n = 123), stable CAD ( n = 184), and acute coronary syndrome (ACS; n = 169). EL was determined from a panoramic tomography. We combined data of widened periapical spaces (WPSs) and apical rarefactions to a score of EL: 1, no EL ( n = 210); 2, ≥1 WPS per 1 apical rarefaction ( n = 222); 3, ≥2 apical rarefactions ( n = 76). Subgingival P. endodontalis was defined by checkerboard DNA-DNA hybridization analysis, and corresponding serum antibodies were determined by ELISA. In our population, 50.4% had WPSs, and 22.8% apical rarefactions. A total of 51.2% of all teeth with apical rarefactions had received endodontic procedures. Subgingival P. endodontalis levels and serum immunoglobulin G were associated with a higher EL score. In the multiadjusted model (age, sex, smoking, diabetes, body mass index, alveolar bone loss, and number of teeth), having WPSs associated with stable CAD (odds ratio [OR] = 1.94, 95% confidence interval [95% CI] = 1.13 to 3.32, P = 0.016) and highest EL score were associated with ACS (OR = 2.46, 95% CI = 1.09 to 5.54, P = 0.030). This association was especially notable in subjects with untreated teeth with apical rarefactions ( n = 59, OR = 2.72, 95% CI = 1.16 to 6.40, P = 0.022). Our findings support the hypothesis that ELs are independently associated with CAD and in particular with ACS. This is of high interest from a public health perspective, considering the high prevalence of ELs and CAD.

Impact of Acute Coronary Syndrome Complicated by Ventricular Fibrillation on Long-term Incidence of Sudden Cardiac Death.

INTRODUCTION AND OBJECTIVES: There is little information on the effect of acute coronary syndrome complicated by ventricular fibrillation on the long-term incidence of sudden cardiac death. We analyzed this effect in a contemporary cohort of patients with acute coronary syndrome. METHODS: We studied 5302 consecutive patients with acute coronary syndrome between December 2003 and December 2012. We compared mortality during and after hospitalization according to the presence or absence of ventricular fibrillation. RESULTS: Ventricular fibrillation was observed in 163 (3.1%) patients, and was early onset in 72.4% of these patients. In-hospital mortality was 36.2% in the group with ventricular fibrillation and 4.7% in the group without (p<.001). After a mean follow-up of 4.7 years (standard deviation, 2.6 years), mortality was 30.7% in the ventricular fibrillation group and 24.7% in the other group (P=.23). After adjusting for confounding variables, the presence of ventricular fibrillation was not associated with an increased risk of death in the follow-up period (hazard ratio=1.29; 95% confidence interval, 0.90-1.87). The cause of death was established in 72% of patients. The incidence of sudden death was 12.9% in the ventricular fibrillation group and 11.9% in the other group (P=.71). Cardiovascular-cause mortality was also similar between the 2 groups (35.5% and 34.4%, respectively. CONCLUSIONS: Patients with acute coronary syndrome complicated by ventricular fibrillation who survive the in-hospital phase do not appear to be at an increased risk of sudden cardiac death or other cardiovascular-cause death.

Coronary neutrophil extracellular trap burden and deoxyribonuclease activity in ST-elevation acute coronary syndrome are predictors of ST-segment resolution and infarct size.

RATIONALE: Mechanisms of coronary occlusion in ST-elevation acute coronary syndrome are poorly understood. We have previously reported that neutrophil (polymorphonuclear cells [PMNs]) accumulation in culprit lesion site (CLS) thrombus is a predictor of cardiovascular outcomes. OBJECTIVE: The goal of this study was to characterize PMN activation at the CLS. We examined the relationships between CLS neutrophil extracellular traps (NETs), bacterial components as triggers of NETosis, activity of endogenous deoxyribonuclease, ST-segment resolution, and infarct size. METHODS AND RESULTS: We analyzed coronary thrombectomies from 111 patients with ST-elevation acute coronary syndrome undergoing primary percutaneous coronary intervention. Thrombi were characterized by immunostaining, flow cytometry, bacterial profiling, and immunometric and enzymatic assays. Compared with femoral PMNs, CLS PMNs were highly activated and formed aggregates with platelets. Nucleosomes, double-stranded DNA, neutrophil elastase, myeloperoxidase, and myeloid-related protein 8/14 were increased in CLS plasma, and NETs contributed to the scaffolds of particulate coronary thrombi. Copy numbers of Streptococcus species correlated positively with dsDNA. Thrombus NET burden correlated positively with infarct size and negatively with ST-segment resolution, whereas CLS deoxyribonuclease activity correlated negatively with infarct size and positively with ST-segment resolution. Recombinant deoxyribonuclease accelerated the lysis of coronary thrombi ex vivo. CONCLUSIONS: PMNs are highly activated in ST-elevation acute coronary syndrome and undergo NETosis at the CLS. Coronary NET burden and deoxyribonuclease activity are predictors of ST-segment resolution and myocardial infarct size.

External coronary artery compression due to prosthetic valve bacterial endocarditis.

Acute coronary syndromes in the setting of infective endocarditis may be the result of coronary compression secondary to periannular aortic valve complications, coronary embolism, obstruction of the coronary ostium due to a large vegetation, coronary atherosclerosis, and severe aortic insufficiency. External coronary artery compression as a result of infective endocarditis is a rare and lethal finding with few reported cases available in the medical literature. We present a rare occurrence of an acute coronary syndrome occurring in the setting of a bioprosthetic aortic valve abscess in which there was no complete coronary occlusion visualized and given the patient's recent unremarkable catheterization and findings of diffuse tapering of the proximal left coronary system, the most likely etiology was external compression secondary to the known aortic root abscess, which caused myocardial ischemia, and was confirmed during surgery. Although uncommon, external compression should be considered in the differential diagnosis of acute coronary syndrome in this setting and coronary angiography can be diagnostic of this entity.

Therapeutic dilemma in a case of acute coronary syndrome (ACS).

An adult male labourer, a smoker and alcoholic was admitted to our hospital with a short history of fever, myalgia, breathlessness and oliguria. On examination he was icteric and hypotensive. Calf muscle tenderness was present. A provisional diagnosis of leptospirosis was made and he was started on treatment with crystalline penicillin. Blood pressure (BP) did not improve with fluids. Inotropes were started. The patient was taken for Slow Low Efficiency Daily Dialysis (SLEDD) during which he developed chest pain. ECG showed an anterolateral myocardial infarction (MI). He also complained of breathlessness and haemoptysis. Antiplatelets were withheld in view of thrombocytopaenia and haemoptysis; heparin could not be given because of the deranged coagulation parameters. The patient was managed symptomatically with nitrates. After the BP improved SLEDD was restarted. On day 3 of admission the patient became tachypnoeic and hypoxic, bilateral coarse crackles were present on auscultation. He was intubated and mechanically ventilated. Suctioning of endotracheal tube revealed fresh blood, and chest CT revealed alveolar haemorrhage. In spite of aggressive resuscitative measures, mechanical ventilation and antibiotics, the patient expired on the 12th day following admission.

A common periodontal pathogen has an adverse association with both acute and stable coronary artery disease.

OBJECTIVE: The aim of this study was to investigate the association between angiographically verified coronary artery disease (CAD) and salivary levels of four major periodontal pathogens. METHODS: The study population (n = 492) was composed of 179 (36.4%) patients with stable CAD, 166 (33.7%) with acute coronary syndrome (ACS), and 119 (24.2%) showing no pathological findings by coronary angiography. All patients were subjected to a detailed oral health examination. The saliva samples were analyzed for lipopolysaccharide activity as well as for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia by quantitative PCR. Serum antibodies levels against A. actinomycetemcomitans were analyzed. RESULTS: The level of bacterial burden was linearly associated with alveolar bone loss (p < 0.001) and bleeding on probing (p = 0.015). The median salivary levels of A. actinomycetemcomitans in pathogen-positive patients were significantly higher in the "Stable CAD" (p = 0.014) and the "ACS" (p = 0.044) groups when compared to "No significant CAD" patients. In logistic regression models, a 10-fold increase in the salivary A. actinomycetemcomitans levels was associated with a risk for stable CAD and ACS with odds ratios (ORs) of 7.47 (95% confidence interval [CI]: 1.57-35.5, p = 0.012) and 4.31 (95% CI: 1.06-17.5, p = 0.041), respectively. The OR for the association of IgA-class antibody levels against A. actinomycetemcomitans with ACS risk was 3.13 (95% CI: 1.38-7.12, p = 0.006)/log(10) unit increase. CONCLUSIONS: High salivary levels of A. actinomycetemcomitans and systemic exposure to the bacterium were associated with increased risk for CAD. These findings emphasize the importance of oral microbiota in cardiovascular risk assessment and therapeutics.

Prognostic role of Helicobacter pylori infection in acute coronary syndrome: a prospective cohort study.

In a prospective cohort study, we evaluated the effect of Helicobacter pylori seropositivity on the risk of future adverse cardiovascular outcomes among patients with acute coronary syndrome (ACS). In 433 patients, IgA and IgG antibodies to H pylori, along with classic risk factors, including hypertension, diabetes, hyperlipidaemia, smoking and family history of coronary artery disease (CAD) were determined. Short and long-term follow-up information on adverse outcomes, defined as recurrence of unstable angina, myocardial infarction, coronary angioplasty, coronary artery bypass graft surgery, and sudden cardiac death was obtained. None of the classic CAD risk factors correlated with incidence of either short- or long-term outcomes. Seropositivity for H pylori was significantly associated with risk of short-term adverse outcomes, and independently predicted their incidence in multivariate regression (R = 3.05, p < 0.001). Results failed to show such an association between H pylori seropositivity and long-term adverse outcomes. H pylori infection may affect short-term prognosis in patients with ACS. Randomised trials are needed to evaluate the role of H pylori eradication in these patients.

Periodontitis and cardiovascular diseases.

Periodontitis is characterized by gingival inflammation and periodontopathic bacteria generate immunological inflammatory responses. Recent epidemiological reports suggest that periodontitis is one of the key risk factors for the onset of cardiovascular diseases. Several studies reported that periodontal bacteria in cardiovascular specimens were frequently detected. We revealed that patients with acute coronary syndrome showed significantly higher serum IgG titers to a strain of periodontopathic bacteria compared with patients with chronic coronary disease. Periodontopathic bacteria were also present in a high percentage of specimens of diseased arteries from patients with Buerger disease or abdominal aortic aneurysm. Although periodontopathic bacteria may play a role in the development of cardiovascular diseases, the influence of these bacteria on the disease has not yet been proven. In this article, we review the relationship between periodontopathic pathogens and cardiovascular diseases to conduct further clinical and experimental investigations in near future.

Isolation of Chlamydia pneumoniae from serum samples of the patients with acute coronary syndrome.

BACKGROUND: Limited body of evidence suggests that lipopolysaccharide of C. pneumoniae as well as C. pneumoniae-specific immune complexes can be detected and isolated from human serum. The aim of this study was to investigate the presence of viable elementary bodies of C.pneumoniae in serum samples of patients with acute coronary syndrome and healthy volunteers. MATERIAL AND METHODS: Serum specimens from 26 healthy volunteers and 56 patients with acute coronary syndrome were examined subsequently by serological (C.pneumoniae-specific IgA and IgG), PCR-based and bacteriological methods. Conventional, nested and TaqMan PCR were used to detect C.pneumoniae genetic markers (ompA and 16S rRNA) in DNA from serum specimens extracted with different methods. An alternative protocol which included culturing high-speed serum sediments in HL cells and further C.pneumoniae growth evaluation with immunofluorescence analysis and TaqMan PCR was established. Pellet fraction of PCR-positive serum specimens was also examined by immunoelectron microscopy. RESULTS: Best efficiency of final PCR product recovery from serum specimens has been shown with specific C. pneumoniae primers using phenol-chloroform DNA extraction protocol. TaqMan PCR analysis revealed that human serum of patients with acute coronary syndrome may contain genetic markers of C. pneumoniae with bacterial load range from 200 to 2000 copies/ml serum. However, reliability and reproducibility of TaqMan PCR were poor for serum specimens with low bacterial copy number (<200 /ml). Combination of bacteriological, immunofluorescence and PCR- based protocols applied for the evaluating HL cells infected with serum sediments revealed that 21.0 % of the patients with acute coronary syndrome have viable forms C.pneumoniae in serum. The detection rate of C.pneumoniae in healthy volunteers was much lower (7.7%). Immunological profile of the patients did not match accurately C.pneumoniae detection rate in serum specimens. Elementary bodies of C.pneumoniae with typical ultrastructural characteristics were also identified in serum sediments using immunoelectron microscopy. CONCLUSIONS: Viable forms C. pneumoniae with typical electron microscopic structure can be identified and isolated from serum specimens of the patients with acute coronary syndrome and some healthy volunteers. Increased detection rate of C. pneumoniae in serum among the patients with an acute coronary syndrome may contribute towards enhanced pro-inflammatory status in cardiovascular patients and development of secondary complications of atherosclerosis.

Impact of intimal pathogen burden in acute coronary syndromes--correlation with inflammation, thrombosis, and autoimmunity.

BACKGROUND: Increasing evidence supports a link between serological evidence of pathogen burden (PB) and the risk for future cardiovascular events. Our study evaluates the intimal presence of 4 pathogens in atheroma, clinically associated with acute coronary syndromes (ACS) and stable angina (SA), and the effect on the expression of intimal C-reactive protein (CRP), tissue factor (TF) and human heat-shock protein 60 (hHSP60). METHODS: Coronary atherectomy specimens retrieved from 60 primary lesions of patients with ACS (n=35) or SA (n=25) were assessed immunohistochemically for the presence of Chlamydia pneumoniae (Cpn), Helicobacter pylori (HP), Cytomegalovirus (CMV) and Epstein­Barr Virus (EBV) and for the expression of CRP, TF, and hHSP60. RESULTS: Analysis revealed eight lesions without, 22 lesions with one, 19 lesions with two, seven lesions with three, and four lesions with four pathogens. Cpn was present in 73%, HP in 31%, CMV in 16%, and EBV in 40%. Mean value of PB in ACS-lesions was significantly increased. Expressions of CRP, TF, and hHSP60 were significantly higher in ACS lesions. The number of infectious pathogens correlated significant with the expressions of CRP, TF, and hHSP60. CONCLUSIONS: Our data demonstrate the impact of PB in plaque instability and suggest local proinflammatory, prothrombotic, and proimmunogenic effects.

Infections as a stimulus for coronary occlusion, obstruction, or acute coronary syndromes.

BACKGROUND: Atherosclerosis is considered to be an inflammatory disease. Infections are a significant cause of inflammation. Acute infections might precipitate acute coronary syndromes (ACS) whereas chronic infections might be stimuli for the development of atherosclerosis. METHODS: Coronary angiograms were done on 211 of 335 patients with ACS and the percentage of coronary obstruction was determined. Serum antibody levels to Chlamydia pneumoniae, C. pneumoniae heat shock protein 60 (CpnHSP60), human heat shock protein 60 (hHSP60), enterovirus (EV), herpes simplex virus (HSV), cytomegalovirus (CMV), and two major periodontal pathogens, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis, were measured in healthy controls (n = 355) and all patients. RESULTS: Serum antibody levels to periodontal pathogens did not correlate with ACS. However, IgA-class antibody levels to Aggregatibacter actinomycetemcomitans (p = 0.021), CpnHSP60 (p = 0.048) an hHSP60 (p = 0.038) were higher in patients with coronary occlusion or obstruction compared to those without any obstruction. Odds ratios for coronary changes in the highest quartile as compared to the lower quartiles were for A. actinomycetemcomitans IgA 7.84 (95% CI 1.02-60.39, p = 0.048), for CpnHSP60 IgA 8.61 (1.12-65.89, p = 0.038), and for human HSP60 IgA 3.51 (0.79-15.69, p = 0.100). CONCLUSIONS: We have previously reported that EV and HSV titres correlated significantly to acute coronary events. They do not correlate to the degree of coronary obstruction as shown here. However, infection by A. actinomycetemcomitans or C. pneumoniae or host response against them associated with coronary obstruction. Clinical coronary events may arise by the effect of acute infections and obstructing lesions by a chronic inflammatory stimulus.