Unstable angina pectoris

A Case Report on Unstable Angina Pectoris Manifesting as Orofacial Pain

Cardiac ischemia, such as angina pectoris or myocardial infarction, is associated with pain in the oral cavity, lower jaw, head, or neck, or spanning from the left upper arm to the shoulder. When presenting to a dentist, however, appropriate treatment for such patients is often delayed, as dental problems are usually the first to be suspected when the chief complaint is orofacial pain. This report describes a case of a 70-year-old woman who was aware of pain and a burning sensation in the oral cavity upon exertion for a year prior to presenting at our clinic. She had been examined by her family physician, an otolaryngologist, and another dentist, none of whom found any abnormalities other than suspected periodontal disease and caries, for which she was treated. An examination at our clinic revealed no abnormal dental findings that would have been consistent with the mandibular pain, however. Although no chest symptoms were reported, pain was elicited on exertion, suggesting cardiogenic toothache. An immediate referral to a cardiologist was therefore made on the same day. The patient visited the cardiology department of the University Hospital of Tokyo Dental College 6 days later. The increased frequency of symptoms on exertion suggested unstable angina, and the patient was admitted to the emergency department on the same day. Emergency coronary angiography showed that right coronary artery #1 was 99% stenosed proximally (highly calcified plaque). The diagnosis was unstable angina pectoris, with the right coronary artery #1 as the responsible lesion, and percutaneous coronary angioplasty was performed on the same day. Subsequently, all the orofacial pain disappeared, confirming unstable angina as the cause. The pain characteristics in this case were consistent with pain associated with cardiac ischemia, which led to the immediate referral to the cardiology department. In cases of toothache associated with cardia ischemia, it is essential to seek cardiological care as soon as possible.

The efficacy and safety of sodium tanshinone ⅡA sulfonate injection in the treatment of unstable angina pectoris: A systematic review and meta-analysis

OBJECTIVE

To systematically evaluate the efficacy and safety of Sodium tanshinone ⅡA sulfonate injection (STS) in the treatment of unstable angina pectoris (UAP).

METHODS

CNKI, Wanfang, VIP, CBM, PubMed, Cochrane Library, Web of Science, Embase were searched by computer. The research covers the clinical randomized controlled trials of STS in the treatment of unstable angina pectoris published from the establishment of the library to January 31, 2023. Two researchers independently screened the literature, extracted data and evaluated the risk of research bias, and then conducted meta-analysis with RevMan5.3 software.

RESULTS

A total of 37 randomized controlled trials were included, involving 3926 patients in total. Meta analysis results showed that, compared with conventional western medicine alone, STS combined with conventional western medicine could reduce the frequency (SMD = -2.61, 95%CI[-4.27, -0.96], P = 0.002) and duration (SMD = -4.01, 95%CI[-6.18, -1.84], P = 0.0003) of angina pectoris, improve ECG efficacy (OR = 3.61, 95%CI[2.79, 4.68], P<0.00001) and clinical symptom efficacy (OR = 4.02, 95%CI[3.32, 4.87], P<0.00001), reduce TG(SMD = -0.60, 95%CI[-1.04, -0.16], P = 0.008), TC(SMD = -3.86, 95%CI[-6.37, -1.34], P = 0.003), and LDL-C(SMD = -1.54, 95%CI[-2.67, -0.42], P = 0.007), decrease plasma viscosity(SMD = -1.02, 95%CI[-1.58, -0.47], P<0.0003), whole blood low shear viscosity(SMD = -0.85, 95%CI[-1.21, -0.49], P<0.00001), whole blood high shear viscosity(SMD = -0.82, 95%CI[-1.44, -0.20], P = 0.009), and erythrocyte aggregation index(SMD = -1.00, 95%CI[-1.75, -0.25], P = 0.009), and bring down CRP(SMD = -1.39, 95%CI[-1.91, -0.86], P<0.00001). The incidence of adverse reactions in the treatment group was higher than that in the control group (OR = 2.26, 95%CI[1.06, 4.85], P = 0.04). Neither of the two groups suffered from abnormal liver and kidney function during the study process.

CONCLUSION

STS combined with routine treatment has a definite clinical efficacy and certain safety in the treatment of UAP, but it needs to be further confirmed by high-quality and low-bias randomized controlled trials in the future.

Non-coding RNAs as biomarkers of myocardial infarction

Non-coding RNAs (ncRNAs) encompass a family of ubiquitous RNA molecules that lack protein-coding potential and have tissue-specific expression. A significant body of evidence indicates that ncRNA's aberrant expression plays a critical role in disease onset and development. NcRNAs' biochemical characteristics such as disease-associated concentration changes, structural stability, and high abundance in body fluids make them promising prognostic and diagnostic biomarkers. Myocardial infarction (MI) is a leading cause of mortality worldwide. Acute myocardial infarction (AMI), the term in use to describe MI's early phase, is generally diagnosed by physical examination, electrocardiogram (ECG), and the presence of specific biomarkers. In this regard, compared to standard MI biomarkers, such as the cardiac troponin isoforms (cTnT & cTnI) and the Creatinine Kinase (CK), ncRNAs appears to provide better sensitivity and specificity, ensuring a rapid and correct diagnosis, an earlier treatment, and consequently a good prognosis for the patients. This review aims to summarize and discuss the most promising and recent data on the potential clinical use of circulating ncRNAs as MI biomarkers. Specifically, we focused primarily on miRNAs and lncRNAs, highlighting their significant specificity and sensitivity, discussing their limitations, and suggesting possible overcoming approaches.

Impact of body mass index on 90-day warfarin requirements: a retrospective chart review

Background:

Rates of obesity continue to rise worldwide as evidenced in the 2017 Centers for Disease Control and Prevention (CDC) report that indicated over 35% of United States (US) citizens are obese, with Louisiana ranked as the fifth most obese state in America. Since large clinical trials tend to exclude obese patients, health care providers are faced with concerns of under- or overdosing these patients on warfarin.

Methods:

This retrospective chart review evaluated patients who reported to a community anticoagulation clinic for warfarin management between 1 June 2017 and 30 September 2017. Along with baseline demographics, chronic use of drugs that have clinically significant interactions with warfarin, social activity such as tobacco use and alcohol consumption, were collected. Body mass indexes (BMI) were collected and categorized according to the World Health Organization definitions as follows: Normal (BMI 18–24.9 kg/m²), Overweight (25–29.9 kg/m²), Obesity Class I (30–34.9 kg/m²), Obesity Class II (35–39.9 kg/m²), Obesity Class III (⩾40 kg/m²). The primary outcome was the mean 90-day warfarin dose required to maintain “intermediate control” or “good control” of international normalized ratio (INR), stratified by BMI classifications. The secondary outcome was the time in therapeutic range (TTR) stratified by BMI classifications.

Results:

A total of 433 patient encounters were included in this study. There was a total of 43 encounters in the Normal BMI category, 111 Overweight encounters, 135 Obesity Class I encounters, 45 Obesity Class II encounters, and 99 Obesity Class III encounters. Approximately 63% of the study population were male, and over 90% the patients were African American. The Obesity Class I and Obesity Class II class required an average of 11.47 mg and 17.10 mg more warfarin, respectively, to maintain a therapeutic INR when compared with the Normal BMI category. These findings were statistically significant with p values of 0.007 and <0.001, respectively. Additionally, upon comparing the Overweight BMI category with the Obesity Class II category, there was a mean warfarin dose difference of 11.22 mg (p = 0.010) more in Obesity Class II encounters to maintain a therapeutic INR. In the secondary analysis of TTR, Overweight category encounters had the highest TTR, whereas encounters in the Normal BMI category had the lowest TTR.

Conclusion:

As BMI increases, there is an increased chronic warfarin requirement to maintain “intermediate control” or “good control” of INR between 2 and 3 in an ambulatory care setting.

Changes in, and predictors of, quality of life among patients with unstable angina after percutaneous coronary intervention

RATIONALE, AIMS AND OBJECTIVES

Changes in, and predictors of, quality of life (QoL) among unstable angina patients are informative for both clinical and public health practice. However, there is little research on this topic, especially in health care settings with limited resources. This study aims to detect changes in QoL and its associated factors among patients with unstable angina after percutaneous coronary intervention.

METHODS

A longitudinal design was conducted with two repeated rounds of measurements, 1 and 3 months after intervention, using the generic SF-36 questionnaire, in 120 patients from Vietnam National Heart Institute. A linear mixed-effects model was used to assess changes in patient QoL over time while adjusting for other covariates.

RESULTS

Only two out of eight QoL subscales (social functioning and emotional well-being) declined after 1 month, but these tended to rise again after 3 months, while scores of all other QoL subscales increased. Adjusting for covariates, QoL increased slightly after 1 month of intervention (β = 0.65, 95%CI = -0.86 to 2.16) but improved by almost six QoL points after 3 months (β = 5.99, 95%CI = 4.48 to 7.50). Four confounders significantly associated with a decline in QoL were older age, being retired, living in rural areas, and having abnormal troponin level.

CONCLUSION

QoL of the patients with unstable angina improves significantly 3 months after intervention, rather than after 1 month. More attention should be given to patients, who are old, retired, live in rural areas and have abnormal troponin level.

Understanding the role of Inflammasome in Angina Pectoris

Angina pectoris, associated with coronary artery disease, a cardiovascular disease where, pain is caused by adverse oxygen supply in myocardium, resulting in contractility and discomfort in chest. Inflammasomes, triggered by stimuli due to infection and cellular stress have identified to play a vital role in the progression of cardiovascular disorders and thus, causing various symptoms like angina pectoris. Nlrp3 inflammasome, a key contributor in the pathogenesis of angina pectoris, requires activation and primary signaling for the commencement of inflammation. Nlrp3 inflammasome elicit out an inflammatory response by emission of pro inflammatory cytokines by ROS (reactive oxygen species) production, mobilization of K+ efflux and Ca2+ and by activation of lysosome destabilization that eventually causes pyroptosis, a programmed cell death process. Thus, inflammasome are considered to be one of the factors involved in the progression of coronary artery diseases and have an intricate role in development of angina pectoris.

Analysis of biomarkers and metabolic pathways in patients with unstable angina based on ultra‑high‑performance liquid chromatography‑quadrupole time‑of‑flight mass spectrometry

Unstable angina (UA) is a coronary disease with a high mortality and morbidity worldwide. The present study aimed to use non-invasive techniques to identify urine biomarkers in patients with UA, so as to provide more information for the early diagnosis and treatment of the disease. Based on metabolomics, urine samples from 28 patients with UA and 28 healthy controls (HCs) were analyzed using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). A total of 16 significant biomarkers that could distinguish between patients with UA and HCs, including D-glucuronic acid, creatinine, succinic acid and N-acetylneuraminic acid, were identified. The major metabolic pathways associated with UA were subsequently analyzed by non-targeted metabolomics. The results demonstrated that amino acid and energy metabolism, fatty acid metabolism, purine metabolism and steroid hormone biosynthetic metabolism may serve important roles in UA. The results of the current study may provide a theoretical basis for the early diagnosis of UA and novel treatment strategies for clinicians. The trial was registered with the Chinese Clinical Trial Registration Center (registration no. ChiCTR-ROC-17013957) at Tianjin University of Traditional Chinese Medicine.

Investigating the multi-target pharmacological mechanism of danhong injection acting on unstable angina by combined network pharmacology and molecular docking

Background

Danhong injection (DHI), which is one of the most well-known Traditional Chinese Medicine (TCM) injections, widely used to treat unstable angina (UA). However, its underlying pharmacological mechanisms need to be further clarified.

Methods

In the present study, network pharmacology was adopted. Firstly, the relative compounds were obtained by a wide-scaled literatures-mining and potential targets of these compounds by target fishing were collected. Then, we built the UA target database by DisGeNET, DigSee, TTD, OMIM. Based on data, protein-protein interaction (PPI) analysis, GO and KEGG pathway enrichment analysis were performed and screen the hub targets by topology. Furthermore, evaluation of the binding potential of key targets and compounds through molecular docking.

Results

The results showed that 12 ingredients of DHI and 27 putative known therapeutic targets were picked out. By systematic analysis, identified 4 hub targets (TNF, TLR4, NFKB1 and SERPINE1) mainly involved in the complex treating effects associated with coagulation and hemostasis, cell membrane region, platelet alpha granule, NF-kappa B signaling pathway and TNF signaling pathway.

Conclusion

The results of this study preliminarily explained the potential targets and signaling pathways of DHI in the treatment of UA, which may help to laid a good foundation for experimental research and further clinical application.

Effects of Trimetazidine Pretreatment on Endothelial Dysfunction and Myocardial Injury in Unstable Angina Patients Undergoing Percutaneous Coronary Intervention

Objectives

Trimetazidine is an anti-ischemic medication licensed for the treatment of angina pectoris. However, the molecular mechanisms underlying its action remain incompletely elucidated. In this study, therefore, we examined the potential beneficial effects of trimetazidine on myocardial injury and endothelial dysfunction in patients with unstable angina in the perioperative period of percutaneous coronary intervention (PCI).

Methods

A total of 97 patients with unstable angina were randomly divided into trimetazidine (n = 48) and control (n = 49) groups. All subjects received standard medical therapy. The trimetazidine group additionally received 20 mg trimetazidine three times daily 24 hours before and after PCI. Serum levels of creatine kinase-muscle/brain (CK-MB), cardiac troponin I (cTnI), heart-type fatty acid-binding protein (h-FABP), von Willebrand factor (vWF), and nitric oxide (NO) were measured before and the morning following PCI.

Results

In the control group, levels of CK-MB, cTnI, and vWF were significantly elevated (P < 0.05) and NO level was decreased after PCI (P < 0.05). By contrast, no significant changes in the levels of these proteins were observed in the trimetazidine group after PCI (P > 0.05). Moreover, h-FABP levels were not significantly altered after PCI whether in the control or in the trimetazidine group (P > 0.05). Finally, a time-dependent increase in the levels of h-FABP from 0 to 6 hours after PCI, followed by a progressive decline, was observed (P < 0.05).

Conclusions

PCI induces endothelial dysfunction and myocardial damage in patients with unstable angina. Trimetazidine therapy in the perioperative period can reduce this damage.

Serum Metabolomics Profiling to Identify Biomarkers for Unstable Angina

Although statistical evidence is clear regarding the dangerousness of unstable angina (UA), a form of coronary heart disease (CHD) characterised by high mortality and morbidity globally, it is important to recognise that diagnostic precision for the condition is unfavourable. In the present research, to gain insight into candidate biomarkers, the author draws on ¹H NMR-based serum metabolic profiling to analyze the unstable angina pectoris (UAP) metabolic signatures; this constitutes an effective way to produce medical diagnosis. 101 unstable angina pectoris patients and 132 healthy controls were enrolled and 22 serum samples from each group were analyzed. Effective separation was noted regarding the UAP and control groups, and, for the former group considered in relation to their counterpart, the serum concentrations of Lac, m-I, lipid, VLDL, 3-HB, and LDL were higher whereas the concentrations of Thr, Cr, Cho, PC/GPC, Glu, Gln, Lys, HDL, Ile, Leu, and Val were lower. The conclusion drawn in view of the results is that the plasma metabolomics examined by ¹H NMR displayed promise for biomarker identification for UA. In addition to this, the analysis illuminated the metabolic processes of UA.

Therapy of unstable angina with the low molecular weight heparins

Unstable angina is in most cases caused by partial or complete coronary artery occlusion due to the disruption of an atherosclerotic plaque and to thrombus formation. An immediate antithrombotic approach is essential to prevent fatal and non-fatal myocardial infarction, and the combination of aspirin and unfractionated heparin has played a pivotal role in the past years. Low molecular weight heparins have improved pharmacokinetic and pharmaco-dynamic properties over unfractionated heparin that have resulted in greater efficacy and safety in the field of venous thromboembolism. Low molecular weight heparins can be administered by once or twice daily subcutaneous injections at fixed, weight-adjusted doses without the need for monitoring. Because of their potential, many recent clinical trials have evaluated their efficacy and safety in the management of patients with unstable angina. Three low molecular weight heparins have so far been tested: nadroparin, dalteparin and enoxaparin. The results of the published trials confirm that the newer compounds are at least as safe and effective as unfractionated heparin, and offer considerable therapeutic advantages. Nevertheless, the different properties of the three compounds and perhaps the different designs of the clinical trials have led to not entirely comparable findings.

Systematic review and meta-analysis of optimal P2Y12 blockade in dual antiplatelet therapy for patients with diabetes with acute coronary syndrome

Background

Patients with diabetes are at increased risk of acute coronary syndromes (ACS) and their mortality and morbidity outcomes are significantly worse following ACS events, independent of other comorbidities. This systematic review sought to establish the optimum management strategy with focus on P2Y₁₂ blockade in patients with diabetes with ACS.

Methods

MEDLINE (1946 to present) and EMBASE (1974 to present) databases, abstracts from major cardiology conferences and previously published systematic reviews were searched to June 2014. Relevant randomised control trials with clinical outcomes for P2Y₁₂ inhibitors in adult patients with diabetes with ACS were scrutinised independently by 2 authors with applicable data was extracted for primary composite end point of cardiovascular death, myocardial infarction (MI) and stroke; enabling calculation of relative risks with 95% CI with subsequent direct and indirect comparison.

Results

Four studies studied clopidogrel in patients with diabetes, with two (3122 patients) having primary outcome data showing superiority of clopidogrel against placebo with RR0.84 (95% CI 0.72–0.99). Irrespective of management strategy, the newer agents prasugrel (2 studies) and ticagrelor (1 study) had a lower primary event rate compared with clopidogrel; RR 0.80 (95% CI 0.66 to 0.97) and RR 0.89 (95% CI 0.77 to 1.02), respectively. When ticagrelor was indirectly compared with prasugrel, there was a trend to an improved primary outcome with prasugrel (RR 1.11 (95% CI 0.94 to 1.31)) particularly in those managed with percutaneous coronary intervention (PCI) (RR 1.23 (95% CI 0.95 to 1.59)). Prasugrel demonstrated a statistical superiority with prevention of further MI with RR 1.48 (95% CI 1.11 to 1.97). This was not at the expense of increased major thrombolysis in MI (TIMI) bleeding rates RR 0.94 (95% CI 0.59 to 1.51).

Conclusions

This meta-analysis shows the addition of a P2Y₁₂ inhibitor is superior to placebo, with a trend favouring the use of prasugrel in patients with diabetes with ACS, particularly those undergoing PCI.

Unstable moyamoya disease: clinical features and impact on perioperative ischemic complications

OBJECT

Unstable moyamoya disease, reasonably defined as cases exhibiting either rapid disease progression or repeated ischemic stroke, represents a challenge in the treatment of moyamoya disease. Despite its overall efficacy, direct bypass for such unstable disease remains controversial in terms of safety. This study aims to reveal factors associated with unstable disease and to assess its impact on postoperative silent or symptomatic ischemic lesions.

METHODS

This retrospective cohort study included both pediatric and adult patients with moyamoya disease who had undergone 140 consecutive direct bypass procedures at Kyoto University Hospital. “Unstable moyamoya disease” was defined as either the rapid progression of a steno-occlusive lesion or repeat ischemic stroke, either occurring within 6 months of surgery. The extent of progression was determined through a comparison of the findings between 2 different MR angiography sessions performed before surgery. The clinical variables of the stable and unstable disease groups were compared, and the association between unstable disease and postoperative diffusion-weighted imaging (DWI)–detected lesion was assessed through univariate and multivariate analyses with generalized estimating equations.

RESULTS

Of 134 direct bypass procedures performed after patients had undergone at least 2 sessions of MR angiography, 24 (17.9%) were classified as cases of unstable disease. Age younger than 3 years (p = 0.029), underlying disease causing moyamoya syndrome (p = 0.049), and radiographic evidence of infarction (p = 0.030) were identified as factors associated with unstable disease. Postoperative DWI-defined lesions were detected after 13 of 140 procedures (9.3%), although only 4 lesions (2.9%) could be classified as a permanent complication. The incidence of postoperative DWI-detected lesions in the unstable group was notable at 33.3% (8 of 24). Univariate analysis revealed that unstable disease (p < 0.001), underlying disease (p = 0.028), and recent stroke (p = 0.012) were factors associated with DWI-detected lesions. Unstable disease remained statistically significant after adjustment for covariates in both the primary and sensitivity analyses (primary analysis: OR 6.62 [95% CI 1.79–24.5]; sensitivity analysis: OR 5.36 [95% CI 1.47–19.6]).

CONCLUSIONS

Unstable moyamoya disease, more prevalent in younger patients and those with underlying disease, is a possible risk factor for perioperative ischemic complications. Recognition of unstable moyamoya disease may contribute to an improved surgical result through focused perioperative management based on appropriate surgical risk stratification.

Unanswered questions in patients with concurrent atrial fibrillation and acute coronary syndrome

The best regimen for the long-term management of patients with atrial fibrillation who present with an acute coronary syndrome or require placement of a coronary stent remains unclear. Clinicians need to understand the risk of stroke, stent thrombosis, and major bleeding associated with treating these patients. Numerous studies and risk assessment schemes provide clinicians with an estimation of the risk of stroke, stent thrombosis, and major bleeding that may be associated with the use or avoidance of dual antiplatelet therapy with concurrent anticoagulation therapy (triple therapy). This review discusses the special antithrombotic needs in patients who have atrial fibrillation and either acute coronary syndrome or a requirement for percutaneous coronary intervention, including the published evidence for non-vitamin K oral anticoagulants, and the unanswered questions in this patient population. In conclusion, until the results of additional ongoing or planned randomized trials are known, clinicians must continue to rely on expert opinion and their own clinical judgment when treating these patients.

A genetic fuzzy system for unstable angina risk assessment

BACKGROUND

Unstable Angina (UA) is widely accepted as a critical phase of coronary heart disease with patients exhibiting widely varying risks. Early risk assessment of UA is at the center of the management program, which allows physicians to categorize patients according to the clinical characteristics and stratification of risk and different prognosis. Although many prognostic models have been widely used for UA risk assessment in clinical practice, a number of studies have highlighted possible shortcomings. One serious drawback is that existing models lack the ability to deal with the intrinsic uncertainty about the variables utilized.

METHODS

In order to help physicians refine knowledge for the stratification of UA risk with respect to vagueness in information, this paper develops an intelligent system combining genetic algorithm and fuzzy association rule mining. In detail, it models the input information's vagueness through fuzzy sets, and then applies a genetic fuzzy system on the acquired fuzzy sets to extract the fuzzy rule set for the problem of UA risk assessment.

RESULTS

The proposed system is evaluated using a real data-set collected from the cardiology department of a Chinese hospital, which consists of 54 patient cases. 9 numerical patient features and 17 categorical patient features that appear in the data-set are selected in the experiments. The proposed system made the same decisions as the physician in 46 (out of a total of 54) tested cases (85.2%).

CONCLUSIONS

By comparing the results that are obtained through the proposed system with those resulting from the physician's decision, it has been found that the developed model is highly reflective of reality. The proposed system could be used for educational purposes, and with further improvements, could assist and guide young physicians in their daily work.

Serum microRNAs profile from genome-wide serves as a fingerprint for diagnosis of acute myocardial infarction and angina pectoris

Background

In order to identify miRNAs expression profiling from genome-wide screen for diagnosis of acute myocardial infarction (AMI) and angina pectoris (AP), we investigated the altered profile of serum microRNAs in AMI and AP patients at a relative early stage.

Methods

Serum samples were taken from 117 AMI patients, 182 AP patients and 100 age-and gender-matched controls. An initial screening of miRNAs expression was performed by Solexa sequencing. Differential expression was validated using RT-qPCR in individuals samples, the samples were arranged in a two-phase selection and validation.

Results

The Solexa sequencing results demonstrated marked upregulation of serum miRNAs in AMI patients compared with controls. RT-qPCR analysis identified a profile of six serum miRNAs (miR-1, miR-134, miR-186, miR-208, miR-223 and miR-499) as AMI biomarkers. MiR-208 and miR-499 were elevated higher in AP cases than in AMI cases. The ROC curves indicated a panel of six miRNAs has a great potential to offer sensitive and specific diagnostic tests for AMI. More especially, the panel of six miRNAs presents significantly differences between the AMI and AP cases.

Conclusions

The six-miRNAs signature identified from genome-wide serum miRNA expression profiling may serves as a fingerprint for AMI and AP diagnosis.

Circulating miRNAs: novel biomarkers of acute coronary syndrome?

Acute coronary syndrome refers to any group of clinical symptoms compatible with acute myocardial infarction (AMI). AMI is a major cause of death and disability worldwide with the greatest risk of death within the first hours of AMI onset. Therefore, delays in ‘ruling in’ AMI may increase morbidity and mortality due to the time lag in initiating therapy. Likewise, since the majority of patients presenting with acute chest pain do not have AMI, the rapid ‘ruling out’ of AMI in those patients would increase emergency department triage efficiency, decrease medical costs, and reduce morbidity and mortality. Thus, the identification of novel biomarkers that improve current strategies and/or accurately identify subjects who are at risk of developing acute and chronic manifestations of cardiovascular disease are desperately needed. This article discusses the potential of peripheral blood microRNAs as clinical biomarkers for the diagnosis and prognosis of cardiovascular diseases such as AMI.

C-reactive protein induces expression of matrix metalloproteinase-9: a possible link between inflammation and plaque rupture

BACKGROUND

Matrix metalloproteases (MMPs) have been implicated in the pathogenesis of acute coronary syndromes (ACS). However, little is known about the mechanisms responsible for MMP expression in ACS. C-reactive protein (CRP) not only is an independent risk factor for cardiovascular events, but also may exert direct pro-atherosclerotic effects. Therefore, we aimed at determining whether CRP might induce MMP-9 in two different experimental conditions: 1) smooth muscle cells (SMCs) in vitro, and 2) patients with ACS.

METHODS AND RESULTS

Effects of increasing concentrations of CRP on MMP-9 expression were evaluated in vitro in human SMCs. TIMP-1 protein expression, the selective inhibitor of MMP-9, was also evaluated. CRP dose-dependently induced MMP-9 expression in SMCs by promoting MMP-mRNA transcription, as well as MMP-9 secretion. In contrast, no differences were found for TIMP-1 protein expression. In vivo, MMP-9 and CRP levels were measured in blood samples obtained from the aorta (Ao) and the coronary sinus (Cs) of patients with normal coronary arteries (controls, n=21), stable angina (n=24), and ACS (n=30). Both MMP-9 and CRP plasma levels were significantly increased across the coronary circulation only in patients with ACS. Interestingly, a significant correlation between MMP-9 and CRP plasma levels was found.

CONCLUSIONS

CRP induced MMP-9 expression and activity in human SMCs in culture; patients presenting with ACS have increased transcoronary plasma levels of MMP-9 and CRP with a significant correlation between these two markers. This may explain the heightened risk of coronary events in subjects with elevated levels of CRP.

Impact of acute coronary syndrome classification and procedural technique on clinical outcomes in patients with coronary bifurcation lesions treated with drug-eluting stents

BACKGROUND

We examined the impact of non-ST-segment elevation acute coronary syndrome (NSTE-ACS) on clinical outcomes in patients with bifurcation lesions treated with drug-eluting stents.

HYPOTHESIS

We hypothesized that NSTE-ACS would be attributable to the increased risk of major adverse cardiac events (MACE) in bifurcation percutaneous coronary intervention.

METHODS

We enrolled 1668 patients, using data from a multicenter real-world bifurcation registry. The primary objective was to compare the 2-year cumulative risk of MACE in patients with NSTE-ACS to those with stable angina. Major adverse cardiac events were defined as the composite endpoint of cardiac death, myocardial infarction (MI), and target-lesion revascularization.

RESULTS

Non-ST-segment elevation acute coronary syndrome was seen in 969 (58.1%) patients and stable angina in 699. Major adverse cardiac events occurred in 7.3% of NSTE-ACS patients and in 5.2% with stable angina (P = 0.042). However, cardiac death, MI, and target-lesion revascularization were similar between the 2 groups. We stratified patients with NSTE-ACS into those with non-ST-segment elevation MI and those with unstable angina. Cumulative risks of 2-year MACEs were 7.0% in non-ST-segment elevation MI patients and 7.5% in unstable angina patients (P = 0.87). In the NSTE-ACS cohort, the baseline lesion length in the side branch (adjusted hazard ratio [HR]: 1.04, 95% confidence interval [CI]: 1.01-1.07, P = 0.022), paclitaxel-eluting stents in the main vessel (adjusted HR: 2.02, 95% CI: 1.21-3.40, P = 0.008), and final kissing ballooning (adjusted HR: 1.88, 95% CI: 1.10-3.21, P = 0.021) were independent predictors of MACE.

CONCLUSIONS

Compared with stable angina patients, the NSTE-ACS patients who underwent bifurcation percutaneous coronary intervention had an increased risk of MACE during the 2-year follow-up.

Thrombopoietin as biomarker and mediator of cardiovascular damage in critical diseases

Thrombopoietin (TPO) is a humoral growth factor originally identified for its ability to stimulate the proliferation and differentiation of megakaryocytes. In addition to its actions on thrombopoiesis, TPO directly modulates the homeostatic potential of mature platelets by influencing their response to several stimuli. In particular, TPO does not induce platelet aggregation per se but is able to enhance platelet aggregation in response to different agonists (“priming effect”). Our research group was actively involved, in the last years, in characterizing the effects of TPO in several human critical diseases. In particular, we found that TPO enhances platelet activation and monocyte-platelet interaction in patients with unstable angina, chronic cigarette smokers, and patients with burn injury and burn injury complicated with sepsis. Moreover, we showed that TPO negatively modulates myocardial contractility by stimulating its receptor c-Mpl on cardiomyocytes and the subsequent production of NO, and it mediates the cardiodepressant activity exerted in vitro by serum of septic shock patients by cooperating with TNF-α and IL-1β. This paper will summarize the most recent results obtained by our research group on the pathogenic role of elevated TPO levels in these diseases and discuss them together with other recently published important studies on this topic.

A comparison of organic and inorganic nitrates/nitrites

Although both organic and inorganic nitrates/nitrites mediate their principal effects via nitric oxide, there are many important differences. Inorganic nitrate and nitrite have simple ionic structures and are produced endogenously and are present in the diet, whereas their organic counterparts are far more complex, and, with the exception of ethyl nitrite, are all medicinally synthesised products. These chemical differences underlie the differences in pharmacokinetic properties allowing for different modalities of administration, particularly of organic nitrates, due to the differences in their bioavailability and metabolic profiles. Whilst the enterosalivary circulation is a key pathway for orally ingested inorganic nitrate, preventing an abrupt effect or toxic levels of nitrite and prolonging the effects, this is not used by organic nitrates. The pharmacodynamic differences are even greater; while organic nitrates have potent acute effects causing vasodilation, inorganic nitrite's effects are more subtle and dependent on certain conditions. However, in chronic use, organic nitrates are considerably limited by the development of tolerance and endothelial dysfunction, whereas inorganic nitrate/nitrite may compensate for diminished endothelial function, and tolerance has not been reported. Also, while inorganic nitrate/nitrite has important cytoprotective effects against ischaemia-reperfusion injury, continuous use of organic nitrates may increase injury. While there are concerns that inorganic nitrate/nitrite may induce carcinogenesis, direct evidence of this in humans is lacking. While organic nitrates may continue to dominate the therapeutic arena, this may well change with the increasing recognition of their limitations, and ongoing discovery of beneficial effects and specific advantages of inorganic nitrate/nitrite.

Pharmacokinetics and pharmacodynamics of the novel PAR-1 antagonist vorapaxar in patients with end-stage renal disease

PURPOSE

To determine whether impaired renal function alters the pharmacokinetics (PK) of vorapaxar or its ability to inhibit thrombin receptor agonist peptide (TRAP)-induced platelet aggregation.

METHODS

This was an open-label study in which 8 patients with end-stage renal disease (ESRD) on hemodialysis and 7 matched (based on age, gender, weight, and height) healthy controls were administered a single 10-mg oral dose of vorapaxar. Blood samples for vorapaxar PK and pharmacodynamic analysis were collected predose and at frequent intervals up to 6 weeks postdose.

RESULTS

Mean vorapaxar bioavailability (based on area under the curve of plasma vorapaxar concentration over time) was identical in the two subject groups; the ESRD/healthy geometric mean ratio (GMR, expressed in percent) was 98. Mean maximum observed plasma concentration (77.4-98.2 ng/mL) was numerically lower in patients with ESRD compared with matched controls (GMR=76; 90% confidence interval=48 to 118). Median time of maximum observed plasma concentration was 2 h in both subject groups. The observed means for elimination half-life were 186 and 231 h in the ESRD and control groups, respectively. Inhibition of platelet aggregation was similar in the two groups. Four out of 15 (27%) subjects reported adverse events, all of which were characterized by the investigator as mild and unrelated to treatment.

CONCLUSIONS

ESRD had no clinically relevant effect on the PK profile of vorapaxar or its ability to inhibit TRAP-induced platelet aggregation.

A comparative study of biomarkers for risk prediction in acute coronary syndrome-Results of the SIESTA (Systemic Inflammation Evaluation in non-ST-elevation Acute coronary syndrome) study

OBJECTIVE

We compared the 1-year predictive value of several inflammatory and non-inflammatory biomarkers in ACS patients.

METHODS

In 610 patients (73.0% male)--36.0% unstable angina (UA) and 64.0% NSTEMI--we assessed high-sensitivity C-reactive protein (hs-CRP), interleukins 6, 10 and 18, soluble CD40 ligand, P- and E-selectin, NT-proBNP, fibrinogen and cystatin C at hospital admission. Two outcomes at 1-year follow up were selected for analysis: (1) all-cause death, MI, UA, or coronary revascularization, and (2) all-cause death, and non-fatal MI. The effect of biomarker levels on endpoints was examined by the Cox proportional hazards model, and their discrimination ability with the C statistic (AUC).

RESULTS

Of 549 patients (90.0%) who completed the 1-year follow up, 206 (37.5%) and 54 (8.9%) reached the first and second composite endpoints, respectively. None of the biomarkers studied improved prediction of the first endpoint. However, considered as continuous variables, and in combination, NT-proBNP and fibrinogen, increased the AUC from 0.64 (95% CI 0.55-0.72) to 0.73 (95% CI 0.64-0.81; p=0.02) for prediction of the second endpoint. Cut-off values for NT-proBNP and fibrinogen, regarding best sensitivity and specificity for prediction of the secondary endpoint were 1043.9 ng/L and 4.47 mg/dL, respectively. For these cut-off points, sensitivity, specificity, positive predictive value and negative predictive value were 40.5% vs 59.5%, 83.3% vs 67.1%, 18.8% vs 14.9% and 93.5% vs 94.4% for NT-proBNP and fibrinogen, respectively.

CONCLUSION

In ACS patients, inflammatory biomarkers offer modest incremental information to that provided by clinical risk markers. Fibrinogen and NT-proBNP measurements, however, improve cardiovascular risk prediction.

Effect of Xuefu Zhuyu Capsule (血府逐瘀胶囊) on the symptoms and signs and health-related quality of life in the unstable angina patients with blood-stasis syndrome after percutaneous coronary intervention: A Randomized controlled trial

OBJECTIVE

Compared with Shengmai Capsule (生脉胶囊, SM), the study was conducted to evaluate the efficacy and safety of Xuefu Zhuyu Capsule (血府逐瘀胶囊, XFZY) on the symptoms and signs and health-related quality of life (HR-QOL) in the unstable angina (UA) patients with blood-stasis syndrome (BSS) after percutaneous coronary intervention (PCI).

METHODS

A randomized, double-blinded, double-dummy, and placebo-controlled trial was applied. Ninety patients, diagnosed as UA and BSS after successful PCI, were enrolled and equally randomized into three groups, XFZY group, SM group, and placebo group, and administered with the corresponding medications respectively for four weeks. The clinical symptoms and signs (CSS), electrocardiography (ECG), and BSS scores were recorded and compared among groups during and after the treatment. Short-form 36 (SF-36) and Seattle Angina Questionnaire (SAQ) were applied to assess the HR-QOL in each group before and after the treatment. Safety indexes (blood routine and liver and kidney function tests) were also examined at the beginning and after the treatment.

RESULTS

Eighty-six patients completed the whole study. After the treatment, the total effective rates of the XFZY group in ameliorating CSS and ECG were 76.7% and 60.0%, respectively, which were obviously higher than those in SM (CSS: 53.3%; ECG: 36.7%) and the placebo (CSS: 43.3%; ECG: 30.0%) groups. After one week's treatment, BSS scores slightly decreased in each group, but no significant differences were found among three groups (P>0.05). After four weeks' treatment, BSS scores in the XFZY group decreased to a lower level compared with SM (P <0.05) and the placebo (P <0.01) groups. After the treatment, the efficacy of XFZY group in improving body pain (BP), general health (GH), vitality (VT), society functioning (SF), role emotional (RE), angina stability (AS), angina frequency (AF), and treatment satisfaction (TS) were better than those in the placebo group (P <0.05,P <0.01). Meanwhile, the dimensions of BP, GH, SF, AS, AF, and TS were better improved than those in the SM group P <0.05). No obvious adverse reaction was found during and after the treatment except one case in the XFZY group reporting of stomach discomfort.

CONCLUSIONS

Compared with SM Capsule treatment, a short-term treatment with XFZY Capsule exhibits better efficacy on CSS and BSS scores, and HR-QOL in UA patients with BSS after PCI. However, its long-term efficacy and safety still needs further investigation.

[Perioperative management of patients with coronary stents in non-cardiac surgery]

In patients with coronary stents scheduled for surgery the question arises whether and how antiplatelet therapy should be continued. Risks of perioperative bleeding and of acute stent thrombosis have to be considered simultaneously. The bleeding risk depends primarily on the kind of surgery and on patient comorbidity. The risk of stent thrombosis is increased in these patients due to the thrombogenic surface of the stents. The main determinants are hereby the time duration after stent implantation, the kind of the stent [uncoated (bare-metal stent, BMS) or coated (drug-eluting stent, DES)], as well as angiographic and clinical patient factors. Therefore, perioperative antiplatelet therapy has to be individually adapted for each patient. Bridging with heparin is ineffective. Bridging with intravenous antiplatelet drugs during the perioperative interruption of oral antiplatelet therapy might be a potential procedure in high-risk patients. Whether bedside monitoring of antiplatelet therapy improves the perioperative management of these patients and reduces adverse outcome is object of current studies.

Evaluation of a new heparin agent in percutaneous coronary intervention: results of the phase 2 evaluation of M118 IN pErcutaNeous Coronary intErvention (EMINENCE) Trial

BACKGROUND

Factor Xa and factor IIa (thrombin) play roles in thrombotic complications after percutaneous coronary intervention. M118 is a novel low-molecular-weight heparin that has been rationally designed to capture the desired attributes of unfractionated heparin (UFH) and low-molecular-weight heparin: Potent activity against factor Xa and IIa, predictable pharmacokinetics after both intravenous and subcutaneous administration, ability to be monitored by use of point-of-care coagulation assays, and reversibility with protamine sulfate. We performed a phase 2 randomized trial to evaluate the safety and feasibility of M118 in the setting of elective percutaneous coronary intervention.

METHODS AND RESULTS

Overall, 503 patients undergoing elective percutaneous coronary intervention at 43 centers in the United States and Canada were randomized in an open-label fashion to 1 of 4 arms: UFH 70 U/kg, M118 50 IU/kg IV, M118 75 IU/kg IV, or M118 100 IU/kg IV. The primary outcome was the composite of death, myocardial infarction, repeat revascularization, stroke, thrombocytopenia, catheter thrombus, bailout use of glycoprotein IIb/IIIa inhibitor, or any bleeding through 30 days. The primary end point occurred in 31.1% of patients randomized to UFH and in 22.7%, 28.3%, and 30.1% of patients randomized to M118 50, 75, and 100 IU/kg, respectively. The primary analysis comparing the rates of the primary end points between the pooled M118 groups versus UFH demonstrated that M118 was noninferior to UFH at preventing percutaneous coronary intervention-related complications (28.4% pooled M118 arms versus 31.1% UFH). The adverse event profiles of M118 and UFH were comparable.

CONCLUSIONS

This phase 2 randomized trial demonstrates that M118 is well tolerated and feasible to use as an anticoagulant in patients undergoing elective percutaneous coronary intervention and forms the basis for further investigation of this agent in ischemic heart disease.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00543400.

Role of acute infection in triggering acute coronary syndromes

Acute coronary syndromes are a leading cause of morbidity and mortality worldwide. The mechanisms underlying the triggering of these events are diverse and include increased coronary and systemic inflammatory activity, dominant prothrombotic conditions, increased biomechanical stress on coronary arteries, variations in the coronary arterial tone, disturbed haemodynamic homoeostasis, and altered myocardial metabolic balance. There is experimental evidence that acute infections can promote the development of acute coronary syndromes, and clinical data strongly support a role for acute infections in triggering these events. In our Review, we summarise the pathogenesis of coronary artery disease and present the evidence linking acute infections with the development of acute coronary syndromes. Greater awareness of this association is likely to encourage research into ways of protecting patients who are at high risk.

In vivo models for the evaluation of antithrombotics and thrombolytics

The development and application of animal models of thrombosis have played a crucial role in the discovery and validation of novel drug targets and the selection of new agents for clinical evaluation, and have informed dosing and safety information for clinical trials. These models also provide valuable information about the mechanisms of action/interaction of new antithrombotic agents. Small and large animal models of thrombosis and their role in the discovery and development of novel agents are described. Methods and major issues regarding the use of animal models of thrombosis, such as positive controls, appropriate pharmacodynamic markers of activity, safety evaluation, species specificity, and pharmacokinetics, are highlighted. Finally, the use of genetic models of thrombosis/hemostasis and how these models have aided in the development of therapies that are presently being evaluated clinically are presented.

Platelet collagen receptor glycoprotein VI as a possible novel indicator for the acute coronary syndrome

BACKGROUND

Platelet collagen receptor glycoprotein VI (GPVI) plays a critical role in acute coronary thrombosis. This prospective study examined the predictive value of GPVI for acute coronary syndromes (ACS) in a large consecutive group of patients with symptomatic coronary artery disease to identify the high-risk cohort with imminent coronary events.

METHODS

We evaluated 1,003 patients with symptomatic coronary artery disease, verified by coronary angiography, and determined the surface expression of GPVI using flow cytometry. In a subgroup of 471 patients, who were treated with aspirin plus clopidogrel for coronary stenting, adenosine disphosphate (20 micromol/L)-induced platelet aggregation was evaluated.

RESULTS

Patients with ACS (n = 485) showed a significantly enhanced GPVI expression compared to patients with stable angina pectoris (SAP; n = 518) (mean fluorescence intensity for ACS 19.8 +/- 5.9; SAP 18.7 +/- 8.5, P = .01). Patients with elevated GPVI levels on admission (GPVI cutoff value > or =18.6 mean fluorescence intensity) had a 1.4-fold relative risk for ACS. Logistic regression analysis showed that an elevated platelet GPVI level may indicate ACS independent of biomarkers of myocardial necrosis including troponin, creatine kinase, and creatine kinase-MB. Patients with increased platelet activation (GPVI expression level > or =18.6) showed significant enhanced residual platelet aggregation despite dual antiplatelet therapy compared to patients with low GPVI levels (P = .028).

CONCLUSIONS

Surface expression of GPVI is enhanced in patients with ACS and indicates an imminent acute coronary event before irreversible myocardial necrosis is evident. High GPVI levels are associated with increased residual platelet aggregation despite antiplatelet therapy. Therefore, GPVI is useful to identify the subgroup of patients with a high risk for coronary stent thrombosis and thromboischemic events.

Evolution of anticoagulant and antiplatelet therapy: benefits and risks of contemporary pharmacologic agents and their implications for myonecrosis and bleeding in percutaneous coronary intervention

Periprocedural myonecrosis, as evidenced by elevated creatine kinase-myocardial bound (CK-MB) levels, occurs in up to 25% of patients undergoing percutaneous coronary intervention (PCI) and has been linked with an increased risk of adverse short- and long-term clinical outcomes. Such myonecrosis arises from three main pathophysiological mechanisms: procedure-related complications, lesion-specific characteristics (e.g., large thrombus burden, plaque volume), and patient-specific characteristics (e.g., genetic predisposition, arterial inflammation). Periprocedural myonecrosis has not been definitively identified as the cause of postprocedural ischemic events, although agents that reduce or prevent thrombosis--including aspirin, thienopyridines, heparin, low-molecular-weight heparins, glycoprotein IIb/IIIa inhibitors, and direct thrombin inhibitors--have been shown to reduce the incidence of ischemic outcomes in this population, as have agents that reduce inflammation (aspirin, statins). At the same time, antithrombotic agents are known to increase the risk of bleeding and the use of transfusions, which have likewise been associated with worse outcomes in these patients. Thus, optimal management of patients undergoing PCI represents a balance between minimizing the risk of ischemic outcomes and simultaneously minimizing the risk of major bleeding. It may be that patients who have only minor, untreated postprocedural elevations in CK-MB level (with no clinical or angiographic signs of ischemia) might have a better prognosis than patients who have normal CK-MB levels but who suffer major bleeding complications.

Antianginal actions of beta-adrenoceptor antagonists

Angina pectoris is usually the first clinical sign of underlying myocardial ischemia, which results from an imbalance between oxygen supply and oxygen demand in the heart. This report describes the pharmacology of beta-adrenoceptor antagonists as it relates to the treatment of angina. The beta-adrenoceptor antagonists are widely used in long-term maintenance therapy to prevent acute ischemic episodes in patients with chronic stable angina. Beta-adrenoceptor antagonists competitively inhibit the binding of endogenous catecholamines to beta1-adrenoceptors in the heart. Their anti-ischemic effects are due primarily to a reduction in myocardial oxygen demand. By decreasing heart rate, myocardial contractility and afterload, beta-adrenoceptor antagonists reduce myocardial workload and oxygen consumption at rest as well as during periods of exertion or stress. Predictable adverse effects include bradycardia and cardiac depression, both of which are a direct result of the blockade of cardiac beta1-adrenoceptors, but adverse effects related to the central nervous system (eg, lethargy, sleep disturbances, and depression) may also be bothersome to some patients. Beta-adrenoceptor antagonists must be used cautiously in patients with diabetes mellitus, peripheral vascular disease, heart failure, and asthma or other obstructive airway diseases. Beta-adrenoceptor antagonists may be used in combination with nitrates or calcium channel blockers, which takes advantage of the diverse mechanisms of action of drugs from each pharmacologic category. Moreover, concurrent use of beta-adrenoceptor antagonists may alleviate the reflex tachycardia that sometimes occurs with other antianginal agents.

Clinical use of clopidogrel in acute coronary syndrome

Several therapeutic approaches have been developed to improve the outcome among patients with acute coronary syndrome (ACS). However, treatment with antithrombotic therapies such as oral glycoprotein IIb/IIIa inhibitors has been limited by the lack of efficacy and excess bleeding complications. As the publication of the landmark study Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE), the clinical benefit of early and intermediate-term use of combined antiplatelet agents--clopidogrel plus aspirin--in non-ST-segment elevation myocardial infarction (NSTEMI) patients became evident. Pretreatment and intermediate-term therapy with clopidogrel in NSTEMI ACS patients undergoing percutaneous coronary intervention (PCI) was further supported by the PCI-CURE trial. Recently, the results of two major trials Clopidogrel as Adjunctive Reperfusion Therapy-Thrombolysis in Myocardial Infarction 28, Clopidogrel and Metoprolol in Myocardial Infarction Trial established the pivotal role of clopidogrel in the other spectrum of ACS-STEMI. Coupled with the results from previous multicentre trials, these two studies provide a guide for the early and long-term use of clopidogrel in the whole spectrum of ACS. A review summarising the results of the recent clinical trials and a discussion on its implications for the clinical management of ACS is presented.

Thrombopoietin contributes to enhanced platelet activation in patients with unstable angina

OBJECTIVES

We sought to investigate the potential role of elevated levels of thrombopoietin (TPO) in platelet activation during unstable angina (UA).

BACKGROUND

Thrombopoietin is a humoral growth factor that does not induce platelet aggregation per se, but primes platelet activation in response to several agonists. No data concerning its contribution to platelet function abnormalities described in patients with UA are available.

METHODS

We studied 15 patients with UA and, as controls, 15 patients with stable angina (SA) and 15 healthy subjects. We measured TPO and C-reactive protein (CRP), as well as monocyte-platelet binding and the platelet expression of P-selectin and of the TPO receptor, c-Mpl. The priming activity of patient or control plasma on platelet aggregation and monocyte-platelet binding and the role of TPO in this effect also were studied.

RESULTS

Patients with UA showed higher circulating TPO levels, as well as increased monocyte-platelet binding, platelet P-selectin expression, and CRP levels, than those with SA and healthy control subjects. The UA patients also showed reduced platelet expression of the TPO receptor, c-Mpl. In vitro, the plasma from UA patients, but not from SA patients or healthy controls, primed platelet aggregation and monocyte-platelet binding, which were both reduced when an inhibitor of TPO was used.

CONCLUSIONS

Thrombopoietin may enhance platelet activation in the early phases of UA, potentially participating in the pathogenesis of acute coronary syndromes.