INTRODUCTION

While a 600 mg loading dose (LD) of clopidogrel has demonstrated superior inhibition of platelet function compared to 300 mg LD, the clinical evidence supporting this superiority is limited. The debate centers on whether higher clopidogrel LD regimen in percutaneous coronary intervention (PCI) outperforms the standard 300 mg LD, with potential benefits being more pronounced in higher-risk patients. Balancing enhanced platelet inhibition to reduce ischemic events against the associated risk of increased bleeding remains a critical consideration in determining the optimal loading dose of clopidogrel for patients with ischemic heart disease.

A systematic literature search for randomized clinical trials (RCTs) was performed comparing 600 mg with 300 mg LD of clopidogrel using PubMed, MEDLINE, Embase, Cochrane, Clinicaltrials.gov and HerdinPH. Studies included those between 2010 and 2023 involving human subjects. The primary efficacy endpoint was a 1-month rate of major adverse cardiac event (MACE) and the primary safety outcome was bleeding adverse effects.

Nine RCTs involving 29,827 patients were included in the efficacy analysis. Mean duration of follow-up was 30 days. Only eight studies were eligible for safety analysis. Compared with standard LD clopidogrel, high LD significantly reduced the incidence of overall MACE (OR: 0.82, 95% CI: 0.74-0.91, p = 0.0002), nonfatal myocardial infarction (OR: 0.56; 95% CI: 0.32-0.99, p = 0.15) and target vessel revascularization (OR: 0.63; 95% CI: 0.41-0.95, p = 0.03), without significant difference in terms of cardiac death (OR: 0.89; 95% CI: 0.76-1.04, p = 0.15) and stroke (OR: 0.92; 95% CI: 0.67-1.26, p = 0.61). However, major bleeding risk was higher in the 600 mg LD (1.9%; 261/13288) compared with 300 mg LD (2.4%; 328/13242) [OR: 1.27; 95% CI: 1.08-1.49, p = 0.005] without significant difference in minor bleeding (OR: 1.05; 95% CI: 0.94-1.17, p = 0.35).

The administration of 600 mg clopidogrel LD reduces the overall risk of MACE with associated increased risk of major bleeding.

INTRODUCTION: Arrhythmias, especially atrial fibrillation (AF) and ventricular arrhythmias, are independent risk factors of mortality in patients with ischaemic heart disease (IHD). While there is a growing body of evidence that suggests an association between obstructive sleep apnoea (OSA) and cardiac arrhythmias, evidence on this relationship in patients with IHD has been scant and inconsistent. We hypothesised that in patients with IHD, severe OSA is associated with an increased risk of nocturnal arrhythmias. METHODS: We studied 103 consecutive patients with IHD who underwent an overnight polysomnography. Exposed subjects were defined as patients who had an apnoea-hypopnoea index (AHI) ≥30/h (severe OSA), and nonexposed subjects were defined as patients who had an AHI <30/h (nonsevere OSA). All electrocardiograms (ECGs) were interpreted by the Somte ECG analysis software and confirmed by a physician blinded to the presence or absence of exposure. Arrhythmias were categorised as supraventricular and ventricular. Arrhythmia subtypes (ventricular, atrial and conduction delay) were analysed as dichotomous outcomes using multiple logistic regression models. RESULTS: Atrial fibrillation and AF/flutter (odds ratio 13.5, 95% confidence interval 1.66-109.83; P = 0.003) were found to be more common in the severe OSA group than in the nonsevere OSA group. This association remained significant after adjustment for potential confounders. There was no significant difference in the prevalence of ventricular and conduction delay arrhythmias between the two groups. CONCLUSION In patients with IHD, there was a significant association between severe OSA and nocturnal AF/flutter. This underscores the need to evaluate for OSA in patients with IHD, as it may have important implications on clinical outcomes.
Humans ; Sleep Apnea, Obstructive/diagnosis* ; Atrial Fibrillation/diagnosis* ; Male ; Female ; Middle Aged ; Polysomnography ; Electrocardiography ; Myocardial Ischemia/complications* ; Aged ; Risk Factors ; Logistic Models

INTRODUCTION: Achieving low-density lipoprotein cholesterol (LDL-C) levels is key to preventing atherosclerotic cardiovascular events. However, many high-risk cardiovascular patients still experience poor LDL-C goal attainment and receive suboptimal lipid-lowering therapy (LLT) prescriptions. Herein, we evaluated LLT prescription patterns, LDL-C goal attainment and cardiovascular mortality among this population group in Singapore. METHODS: This prospective observational cohort study included 555 patients with ischaemic heart disease (IHD) admitted to the hospital in 2020. The LLT prescriptions, corresponding LDL-C levels and cardiovascular outcomes were assessed over a 24-month period. RESULTS: Most participants were male (82.3%), with 48.5% identified as Chinese. High-intensity statin prescriptions increased from 45.4% at hospital admission to 87.1% at discharge and remained stable at approximately 80% at 6, 12, and 24 months post-discharge. Combination LLT prescriptions increased from 12.3% at discharge to 33.8% by 24 months. Ezetimibe was the most commonly prescribed second-line LLT (40.8%), followed by inclisiran (1.09%) and anti-proprotein convertase subtilisin/kexin type 9 monoclonal antibody therapies (0.87%). Over 24 months, LDL-C goal attainment rates were 22.1% for LDL-C < 1.4 mmol/L and 47.2% for LDL-C < 1.8 mmol/L. Multivariable Cox proportional hazards regression indicated that achieving LDL-C < 1.8 mmol/L goal was associated with a reduction in all-cause mortality at 24 months (hazard ratio 0.53, 95% confidence interval 0.30-0.94, P = 0.030). CONCLUSION Treatment gaps in lipid management persist in 80% of the study population, indicating that statin monotherapy alone is insufficient to achieve LDL-C goals. Greater efforts to improve LDL-C goal attainment rates in high-risk cardiovascular patients are imperative.
Humans ; Male ; Cholesterol, LDL/blood* ; Female ; Myocardial Ischemia/drug therapy* ; Middle Aged ; Prospective Studies ; Aged ; Singapore/epidemiology* ; Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use* ; Ezetimibe/therapeutic use* ; Anticholesteremic Agents/therapeutic use* ; Treatment Outcome

INTRODUCTION: Outcomes after SARS-CoV-2 Omicron infection in patients with heart failure (HF) and ischaemic heart disease (IHD) remain poorly defined. METHOD: In a highly vaccinated cohort of adult Singapore citizens and permanent residents, we used Cox proportional hazards models (adjusted for sociodemographic variables and comorbidities) to compare the risks of Omicron infection, COVID-19- related hospitalisation, and severe COVID-19 between indivi-duals with HF or IHD and matched controls without these conditions. RESULTS: From national databases, we identified 15,426 HF patients matched 1:∼3 to 41,221 controls, and 110,442 IHD patients matched 1:∼2 to 223,843 controls. Over 80% of HF and IHD patients had received at least 3 vaccine doses. During the Omicron-predominant period, both HF and IHD cohorts demonstrated higher adjusted risks of COVID-19 hospitalisation compared with matched controls (HF: adjusted hazard ratio [aHR] 1.77, 95% confidence interval [CI] 1.65-1.90; IHD: aHR 1.21, 95% CI 1.17-1.26). Among those with at least 1 HF-or IHD-related admission in the prior year, hospitalisation risk was further elevated (HF: aHR 1.27, 95% CI 1.13-1.42; IHD: aHR 1.11, 95% CI 1.01-1.23). Receipt of ≥3 vaccine doses was associated with substantially lower risk of severe COVID-19 versus only 2 doses (HF: aHR 0.35, 95% CI 0.28-0.43; IHD: aHR 0.27, 95% CI 0.23-0.32). A fourth dose conferred additional reductions in infection and adverse outcomes, though CIs for infection overlapped with those for 3 doses. CONCLUSION During Omicron predominance, HF and IHD patients experienced greater risk of COVID-19 hospitalisation and severe COVID-19 versus matched controls. Booster vaccinations attenuated these risks. Individuals with recent HF/IHD admissions should be prioritised for receipt of booster vaccine doses.
Humans ; COVID-19/complications* ; Male ; Heart Failure/complications* ; Myocardial Ischemia/complications* ; Female ; Middle Aged ; Hospitalization/statistics & numerical data* ; Aged ; COVID-19 Vaccines/administration & dosage* ; Singapore/epidemiology* ; SARS-CoV-2 ; Proportional Hazards Models ; Adult ; Case-Control Studies ; Vaccination/statistics & numerical data*

This study aims to investigate the ameliorating effect of Corni Fructus(CF) on the myocardial ischemic injury and the pharmacokinetic properties of characteristic components of CF. The mouse model of isoproterenol-induced myocardial ischemia was established and administrated with the aqueous extract of CF. The general efficacy of CF in ameliorating the myocardial ischemic injury was evaluated based on the cardiac histopathology and the levels of myocardial injury markers: creatine kinase isoenzyme(CK-MB) and cardiac troponin I(cTn-I). The metabolomics analysis was carried out for the heart and serum samples of mice to screen the biomarkers of CF in ameliorating the myocardial ischemic injury and then the predicted biomarkers were submitted to metabolic pathway enrichment. The pharmacokinetic analysis was performed for morroniside, loganin, and cornuside Ⅰ in mouse heart and serum samples to obtain the pharmacokinetic parameters of these components. The pharmacokinetic parameters were then integrated on the basis of self-defined weighting coefficients to simulate an integrated pharmacokinetic profile of CF iridoid glycosides in the heart and serum of the mouse model of myocardial ischemia. The results indicated that CF reduced the pathological damage to cardiac cells and tissue(hematoxylin-eosin staining) and lowered the levels of CK-MB and cTn-I in the serum of the mouse model of myocardial ischemia(P<0.01). Metabolomics analysis screed out 31 endogenous metabolites in the heart and 35 in the serum as biomarkers of CF in ameliorating the myocardial ischemic injury. These biomarkers were altered by modeling and restored by CF. Six metabolic pathways in the heart and 5 in the serum were enriched based on these metabolic markers. The main integrated pharmacokinetic parameters of CF iridoid glycosides were T_(max)=1 h, t_(1/2)=(1.52±0.05) h in the heart and T_(max)=1 h, t_(1/2)=(1.56±0.50) h in the serum. Both concentration-time curves showed a double-peak phenomenon. In conclusion, CF demonstrated the cardioprotective effect by regulating metabolic pathways such as taurine and hypotaurine metabolism, and pantothenic acid and coenzyme A biosynthesis. The integrated pharmacokinetics reflect the general pharmacokinetic properties of characteristic components in CF.
Animals ; Cornus/chemistry* ; Mice ; Metabolomics ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Myocardial Ischemia/metabolism* ; Humans ; Troponin I/metabolism* ; Myocardium/pathology* ; Disease Models, Animal ; Biomarkers/metabolism* ; Creatine Kinase, MB Form/metabolism*

The medicinal materials of Bawei Chenxiang Pills(BCPs) were extracted via three methods: reflux extraction by water, reflux extraction by 70% ethanol, and extraction by pure water following reflux extraction by 70% ethanol, yielding three extracts of ST, CT, and CST. The efficacy of ST(760 mg·kg~(-1)), CT(620 mg·kg~(-1)), and CST(1 040 mg·kg~(-1)) were evaluated by acute myocardial ischemia(AMI) and p-chlorophenylalanine(PCPA)-induced insomnia in mice, respectively. Western blot was further utilized to investigate their hypnosis mechanisms. The main chemical components of different extracts were identified by the UPLC-Q-Exactive-MS technique. The results showed that CT and CST significantly increased the ejection fraction(EF) and fractional shortening(FS) of myocardial infarction mice, reduced left ventricular internal dimension at end-diastole(LVIDd) and left ventricular internal dimension at end-systole(LVIDs). In contrast, ST did not exhibit significant effects on these parameters. In the insomnia model, CT significantly reduced sleep latency and prolonged sleep duration, whereas ST only prolonged sleep duration without shortening sleep latency. CST showed no significant effects on either sleep latency or sleep duration. Additionally, both CT and ST upregulated glutamic acid decarboxylase 67(GAD67) protein expression in brain tissue. A total of 15 main chemical components were identified from CT, including 2-(2-phenylethyl) chromone and 6-methoxy-2-(2-phenylethyl) chromone. Six chemical components including chebulidic acid were identified from ST. The results suggested that chromones and terpenes were potential anti-myocardial ischemia drugs of BCPs, and tannin and phenolic acids were potential hypnosis drugs. This study enriches the pharmacological and chemical research of BCPs, providing a basis and reference for their secondary development, quality standard improvement, and clinical application.
Animals ; Drugs, Chinese Herbal/isolation & purification* ; Mice ; Male ; Sleep Initiation and Maintenance Disorders/physiopathology* ; Humans ; Myocardial Infarction/drug therapy* ; Myocardial Ischemia/drug therapy*

OBJECTIVES: To clarify the role of hippocampal glutamate system in regulating HPA axis in mediating the effect of electroacupuncture (EA) at the heart meridian for improving myocardial injury in rats with acute myocardial ischemia (AMI). METHODS: Male SD rats were randomized into sham-operated group, AMI group, EA group, and L-glutamic acid+EA group (n=9). Rat models of AMI were established by left descending coronary artery ligation, and EA was applied at the "Shenmen-Tongli" segment; the rats in L-glutamic acid+EA group were subjected to microinjection of L-glutamic acid into the bilateral hippocampus prior to AMI modeling and EA treatment. Cardiac functions of the rats were evaluated using echocardiography, and ECG and heart rate variation (HRV) were analyzed using PowerLab and LabChart. Pathological changes in the myocardial tissue was examined using HE staining, and serum levels of myocardial enzymes were detected with ELISA. Myocardial expressions of TH and GAP43 were detected with immunohistochemistry, and colocalization of VGLUT1, VGLUT2 and c-fos were observed using immunofluorescence staining; the expressions of VGLUT1, VGLUT2, NMDAR1 and NMDAR2B were detected using Western blotting. RESULTS: The rat models of AMI showed significantly decreased LVEF and LVFS and increased serum levels of myocardial enzymes in positive correlation with the HPA axis. Numerous TH- and GAP43-positive cells were observed in the hippocampus, where the expressions of NE and E, neurons colabeled with VGLUT1, VGLUT2 and c-fos, and expressions of VGLUT1, VGLUT2, NMDAR1, NMDAR2B and Glu increased significantly. All these changes were significantly improved by interventions with EA as compared with those in AMI and L-Glutamate+EA groups. CONCLUSIONS In rats with AMI, EA at the heart meridian can regulate excessive glutamate release in the hippocampus, thereby inhibiting HPA axis hyperactivity and reducing sympathetic nerve activity to protect the myocardial tissue.
Animals ; Electroacupuncture ; Male ; Rats, Sprague-Dawley ; Hippocampus/metabolism* ; Rats ; Glutamic Acid/metabolism* ; Myocardial Ischemia/physiopathology* ; Hypothalamo-Hypophyseal System/physiopathology* ; Pituitary-Adrenal System/physiopathology* ; Receptors, N-Methyl-D-Aspartate/metabolism*

Zishen Huoxue decoction (ZSHX) enhances cardiomyocyte viability following hypoxic stress; however, its upstream therapeutic targets remain unclear. Network pharmacology and RNA sequencing analyses revealed that ZSHX target genes were closely associated with mitophagy and apoptosis in the mitochondrial pathway. In vitro, ZSHX inhibited pathological mitochondrial fission following hypoxic stress, regulated FUN14 domain-containing protein 1 (FUNDC1)-related mitophagy, and increased the levels of mitophagy lysosomes and microtubule-associated protein 1 light chain 3 beta II (LC3II)/translocase of outer mitochondrial membrane 20 (TOM20) expression while inhibiting the over-activated mitochondrial unfolded protein response. Additionally, ZSHX regulated the stability of beta-tubulin through Sirtuin 5 (SIRT5) and could modulate FUNDC1-related synergistic mechanisms of mitophagy and unfolded protein response in the mitochondria (UPR^mt) via the SIRT5 and -β-tubulin axis. This targeting pathway may be crucial for cardiomyocytes to resist hypoxia. Collectively, these findings suggest that ZSHX can protect against cardiomyocyte injury via the SIRT5-β-tubulin axis, which may be associated with the synergistic protective mechanism of SIRT5-β-tubulin axis-related mitophagy and UPR^mt on cardiomyocytes.
Mitophagy/drug effects* ; Tubulin/genetics* ; Animals ; Myocytes, Cardiac/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Sirtuins/genetics* ; Unfolded Protein Response/drug effects* ; Myocardial Ischemia/genetics* ; Rats ; Humans ; Rats, Sprague-Dawley ; Apoptosis/drug effects* ; Male

OBJECTIVE: Emerging evidence suggests that exposure to ultrafine particulate matter (UPM, aerodynamic diameter < 0.1 µm) is associated with adverse cardiovascular events. Previous studies have found that Shenlian (SL) extract possesses anti-inflammatory and antiapoptotic properties and has a promising protective effect at all stages of the atherosclerotic disease process. In this study, we aimed to investigated whether SL improves UPM-aggravated myocardial ischemic injury by inhibiting inflammation and cell apoptosis. METHODS: We established a mouse model of MI+UPM. Echocardiographic measurement, measurement of myocardialinfarct size, biochemical analysis, enzyme-linked immunosorbent assay (ELISA), histopathological analysis, Transferase dUTP Nick End Labeling (TUNEL), Western blotting (WB), Polymerase Chain Reaction (PCR) and so on were used to explore the anti-inflammatory and anti-apoptotic effects of SL in vivo and in vitro. RESULTS: SL treatment can attenuate UPM-induced cardiac dysfunction by improving left ventricular ejection fraction, fractional shortening, and decreasing cardiac infarction area. SL significantly reduced the levels of myocardial enzymes and attenuated UPM-induced morphological alterations. Moreover, SL significantly reduced expression levels of the inflammatory cytokines IL-6, TNF-α, and MCP-1. UPM further increased the infiltration of macrophages in myocardial tissue, whereas SL intervention reversed this phenomenon. UPM also triggered myocardial apoptosis, which was markedly attenuated by SL treatment. The results of in vitro experiments revealed that SL prevented cell damage caused by exposure to UPM combined with hypoxia by reducing the expression of the inflammatory factor NF-κB and inhibiting apoptosis in H9c2 cells. CONCLUSION Overall, both in vivo and in vitro experiments demonstrated that SL attenuated UPM-aggravated myocardial ischemic injury by inhibiting inflammation and cell apoptosis. The mechanisms were related to the downregulation of macrophages infiltrating heart tissues.
Animals ; Apoptosis/drug effects* ; Particulate Matter/adverse effects* ; Mice ; Male ; Inflammation/drug therapy* ; Drugs, Chinese Herbal/therapeutic use* ; Mice, Inbred C57BL ; Myocardial Ischemia/drug therapy* ; Cell Line

OBJECTIVE: Observational studies have shown inconsistent associations of loneliness or social isolation (SI) with ischemic heart disease (IHD), with unknown mediators. METHODS: Using data from genome-wide association studies of predominantly European ancestry, we performed a bidirectional two-sample Mendelian Randomization (MR) study to estimate causal effects of loneliness ( N = 487,647) and SI traits on IHD ( N = 184,305). SI traits included whether individuals lived alone, participated in various types of social activities, and how often they had contact with friends or family ( N = 459,830 to 461,369). A network MR study was conducted to evaluate the mediating roles of 20 candidate mediators, including metabolic, behavioral and psychological factors. RESULTS: Loneliness increased IHD risk ( OR= 2.129; 95% confidence interval [ CI]: 1.380 to 3.285), mediated by body fat percentage, waist-hip ratio, total cholesterol, and low-density lipoprotein cholesterol. For SI traits, only fewer social activities increased IHD risk ( OR= 1.815; 95% CI: 1.189 to 2.772), mediated by hypertension, high-density lipoprotein cholesterol, triglycerides, fasting insulin, and smoking cessation. No reverse causality of IHD with loneliness and SI was found. CONCLUSION These findings suggested more attention should be paid to individuals who feel lonely and have fewer social activities to prevent IHD, with several mediators as prioritized targets for intervention.
Loneliness/psychology* ; Humans ; Mendelian Randomization Analysis ; Social Isolation ; Myocardial Ischemia/etiology* ; Male ; Female ; Middle Aged ; Genome-Wide Association Study ; Risk Factors ; Aged