Coronary no-reflow in the modern era: a review of advances in diagnostic techniques and contemporary management

Tongguan capsule for treating myocardial ischemia-reperfusion injury: integrating network pharmacology and mechanism study

CONTEXT

Although Tongguan capsule (TGC) is used in the treatment of coronary atherosclerotic disease, the exact mechanism remains unclear.

OBJECTIVE

Network pharmacology and experimental validation were applied to examine the mechanism of TGC for treating myocardial ischemia-reperfusion injury (MIRI).

MATERIALS AND METHODS

The components and candidate targets were searched based on various databases such as TCMSP, TCMID, BATMAN-TCM. The binding ability was determined by molecular docking. The ischemia-reperfusion (I/R) model was constructed by ligating the left anterior descending (LAD) coronary artery. APOE^-/- mice were divided into three groups (n = 6): Sham group, I/R group, and TGC group (1 g/kg/d). To further verification, HCAEC cells were subjected to hypoxia-reoxygenation (H/R) to establish in vitro model.

RESULTS

The compounds, such as quercetin, luteolin, tanshinone IIA, kaempferol and bifendate, were obtained after screening. The affinity values of the components with GSK-3β, mTOR, Beclin-1, and LC3 were all <-5 kcal/mol. In vivo, TGC improved LVEF and FS, reducing infarct size. In vitro, Hoechst 33258 staining result showed TGC inhibited apoptosis. Compare with the H/R model, TGC treatment increased the levels of GSK-3β, LC3, and Beclin1, while decreasing the expression of mTOR and p62 (p < 0.05).

DISCUSSION AND CONCLUSION

The findings revealed that TGC exerted a cardioprotective effect by up regulating autophagy-related proteins through the mTOR pathway, which may be a therapeutic option for MIRI. However, there are still some limitations in this research. It is necessary to search more databases to obtain information and further demonstrated through randomized controlled trials for generalization.

Myocardial Perfusion in ST-Segment Elevation Myocardial Infarction Patients After Percutaneous Coronary Intervention: Influencing Factors and Intervention Strategies

Aim We aim to explore the factors influencing myocardial perfusion in patients with acute ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PPCI) and evaluate the effects of different intervention strategies on myocardial perfusion improvement. Methods A retrospective analysis was conducted on 300 patients with STEMI who underwent primary percutaneous coronary intervention (PPCI) at our hospital between January 2020 and December 2022. Based on post-procedural coronary angiography results using the thrombolysis in myocardial infarction (TIMI) blood flow grade and myocardial blush grade (MBG), patients were categorized into two groups: the normal perfusion group (TIMI grade 3 or MBG 2-3, n=180) and the impaired perfusion group (TIMI grades 0-2 or MBG 0-1, n=120). The impaired perfusion group was further divided using a random number table into the thrombus aspiration-only group (control group, n=60) and the thrombus aspiration combined with nicorandil group (nicorandil group, n=60). A 1:1 propensity score matching method was employed to adjust for baseline characteristics between the groups. Clinical characteristics, hematological parameters, coronary lesion features, and percutaneous coronary intervention (PCI) technical parameters were compared between the matched groups. Additionally, a multivariate logistic regression analysis was performed to identify independent risk factors influencing myocardial perfusion. Furthermore, the post-procedural myocardial perfusion, cardiac function, and clinical prognosis were compared between the control and nicorandil groups. Results After matching, the baseline characteristics of the two groups were compared. The impaired perfusion group had older age, higher proportion of male patients, higher rates of diabetes and hypertension, longer time from symptom onset to balloon dilation, higher peak cardiac troponin I (cTnI) levels, higher proportion of left main or multivessel involvement, heavier coronary lesion burden, and lower balloon inflation pressure (P<0.05). Multivariate logistic regression analysis revealed that age of ≥65 years (odds ratio {OR}=2.34, 95% confidence interval {CI}=1.23-4.46, P<0.01), time from symptom onset to balloon dilation of ≥6 hours (OR=3.12, 95% CI=1.67-5.83, P<0.01), peak cTnI level of ≥100 ng/mL (OR=4.27, 95% CI=2.18-8.36, P<0.01), left main or multivessel involvement (OR=2.86, 95% CI=1.51-5.41, P<0.01), and balloon inflation pressure of <8 atm (OR=3.45, 95% CI=1.79-6.65, P<0.01) were independent risk factors affecting myocardial perfusion. In the intervention analysis, the nicorandil group showed superior post-procedural TIMI blood flow grade, MBG, left ventricular ejection fraction (LVEF), and New York Heart Association (NYHA) functional classification compared to the control group (P<0.05). During a six-month follow-up, the nicorandil group had a lower incidence of major adverse cardiovascular events (MACE) compared to the control group (P<0.05). Conclusion Age, time from symptom onset to balloon dilation, peak cTnI level, extent of coronary artery lesions, and balloon inflation pressure were identified as independent risk factors affecting myocardial perfusion in STEMI patients after PCI. Compared to simple thrombus aspiration, thrombus aspiration combined with nicorandil demonstrated better improvement in myocardial perfusion, cardiac function, and clinical outcomes for patients with impaired perfusion.

Shenlian extract decreases mitochondrial autophagy to regulate mitochondrial function in microvascular to alleviate coronary artery no-reflow

Shenlian (SL) extract has been proven to be effective in the prevention and treatment of atherosclerosis and myocardial ischemia. However, the function and molecular mechanisms of SL on coronary artery no-reflow have not been fully elucidated. This study was designed to investigate the contribution of SL extract in repressing excessive mitochondrial autophagy to protect the mitochondrial function and prevent coronary artery no-reflow. The improvement of SL on coronary artery no-reflow was observed in vivo experiments and the molecular mechanisms were further explored through vitro experiments. First, a coronary artery no-reflow rat model was built by ligating the left anterior descending coronary artery for 2 hr of ischemia, followed by 24 hr of reperfusion. Thioflavin S (6%, 1 ml/kg) was injected into the inferior vena cava to mark the no-reflow area. Transmission electron microscopy was performed to observe the cellular structure, mitochondrial structure, and mitochondrial autophagy of the endothelial cells. Immunofluorescence was used to observe the microvascular barrier function and microvascular inflammation. Cardiac microvascular endothelial cells (CMECs) were isolated from rats. The CMECs were deprived of oxygen-glucose deprivation (OGD) for 2 hr and reoxygenated for 4 hr to mimic the Myocardial ischemia-reperfusion (MI/R) injury-induced coronary artery no-reflow in vitro. Mitochondrial membrane potential was assessed using JC-1 dye. Intracellular adenosine triphosphate (ATP) levels were determined using an ATP assay kit. The cell total reactive oxygen species (ROS) levels and cell apoptosis rate were analyzed by flow cytometry. Colocalization of mitochondria and lysosomes indirectly indicated mitophagy. The representative ultrastructural morphologies of the autophagosomes and autolysosomes were also observed under transmission electron microscopy. The mitochondrial autophagy-related proteins (LC3II/I, P62, PINK, and Parkin) were analyzed using Western blot analysis. In vivo, results showed that, compared with the model group, SL could reduce the no-reflow area from 37.04 ± 9.67% to 18.31 ± 4.01% (1.08 g·kg^-1 SL), 13.79 ± 4.77% (2.16 g·kg^-1 SL), and 12.67 ± 2.47% (4.32 g·kg^-1 SL). The extract also significantly increased the left ventricular ejection fraction (EF) and left ventricular fractional shortening (FS) (p < 0.05 or p < 0.01). The fluorescence intensities of VE-cadherin, which is a junctional protein that preserves the microvascular barrier function, decreased to ~74.05% of the baseline levels in the no-reflow rats and increased to 89.87%(1.08 g·kg^-1 SL), 82.23% (2.16 g·kg^-1 SL), and 89.69% (4.32 g·kg^-1 SL) of the baseline levels by SL treatment. SL administration repressed the neutrophil migration into the myocardium. The oxygen-glucose deprivation/reoxygenation (OGD/R) model was induced in vitro to mimic microvascular ischemia-reperfusion injury. The impaired mitochondrial function after OGD/R injury led to decreased ATP production, calcium overload, the excessive opening of the Mitochondrial Permeability Transition Pore, decreased mitochondrial membrane potential, and reduced ROS scavenging ability (p < 0.05 or p < 0.01). The normal autophagosomes (double-membrane vacuoles with autophagic content) in the sham group were rarely found. The large morphology and autophagosomes were frequently observed in the model group. By contrast, SL inhibited the excessive activation of mitochondrial autophagy. The mitochondrial autophagy regulated by the PINK/Parkin pathway was excessively activated. However, administration of SL prevented the activation of the PINK/Parkin pathway and inhibited excessive mitochondrial autophagy to regulate mitochondrial dysfunction. Results also demonstrated that mitochondrial dysfunction stimulated endothelial cell barrier dysfunction, but Evans blue transmission was significantly decreased and transmembrane resistance was increased significantly by SL treatment (p < 0.05 or p < 0.01). Carbonylcyanide-3-chlorophenylhydrazone (CCCP) could activate the PINK/Parkin pathway. CCCP reversed the regulation of SL on mitochondrial autophagy and mitochondrial function. SL could alleviate coronary artery no-reflow by protecting the microvasculature by regulating mitochondrial function. The underlying mechanism was related to decreased mitochondrial autophagy by the PINK/Parkin pathway.

The Systemic Immune Inflammatory Index Predicts No-Reflow Phenomenon after Primary Percutaneous Coronary Intervention in Older Patients with STEMI

Purpose: Coronary no-reflow phenomenon (NRP), a common adverse complication in patients with ST-segment elevation myocardial infarction (STEMI) treated by percutaneous coronary intervention (PCI), is associated with poor patient prognosis. In this study, the correlation between the systemic immune-inflammation index (SII) and NRP in older patients with STEMI was studied, to provide a basis for early identification of high-risk patients and improve their prognosis.

Materials and methods: Between January 2017 and June 2020, 578 older patients with acute STEMI admitted to the Department of Cardiology of Hebei General Hospital for direct PCI treatment were selected for this retrospective study. Patients were divided into an NRP group and normal-flow group according to whether NRP occurred during the operation. Clinical data and the examination indexes of the two groups were collected. Logistic regression was used to analyze the independent predictors of NRP, and the receiver operating characteristic curve was used to further analyze the ability of SII to predict NRP in older patients with STEMI.

Results: Multivariate logistic analysis indicated that hypertension (OR=2.048, 95% CI:1.252–3.352, P=0.004), lymphocyte count (OR=0.571, 95% CI:0.368–0.885, P=0.012), platelet count (OR=1.009, 95% CI:1.005–1.013, P<0.001), hemoglobin (OR=1.015, 95% CI:1.003–1.028, P=0.018), multivessel disease (OR=2.237, 95% CI:1.407–3.558, P=0.001), and SII≥1814 (OR=3.799, 95% CI:2.190–6.593, P<0.001) were independent predictors of NRP after primary PCI in older patients with STEMI. Receiver operating characteristic curve analysis demonstrated that SII had a high predictive value for NRP (AUC=0.738; 95% CI:0.686–0.790), with the best cut-off value of 1814, a sensitivity of 52.85% and a specificity of 85.71%.

Conclusion: For older patients with STEMI undergoing primary PCI, SII is a valid predictor of NRP.

Effect of intravenous application of nicorandil on area of myocardial infarction in patients with STEMI during the perioperative stage of PCI

OBJECTIVE

The aim of the present study was to evaluate the effectiveness and safety of nicorandil in improving the area of myocardial infarction in patients with acute myocardial infarction (AMI).

METHODS

One hundred and twenty patients with acute ST-segment elevation myocardial infarction (STEMI) admitted to our hospital between December 1, 2018 and December 31, 2019 were selected and randomly allocated to the experimental group (group A, n = 60) and the control group (group B, n = 60). In the experimental group, an infusion of nicorandil was given intravenously before the first balloon dilation or 1 minute before the stent placement, and with the completion of the infusion, nicorandil maintenance infusion was given. In the control group, only balloon dilation and stent placement were undertaken.

RESULTS

The postoperative peak levels of myoglobin, creatine kinase isoform and hypersensitive troponin T were significantly lower in group A than in group B (p < 0.05). Moreover, the left ventricular ejection fraction (LVEF) on the 180th day post operation was substantially greater in group A than in group B (p < 0.01), and the area of myocardial infarction was significantly smaller in patients in group A than those in group B on the 180th day post operation (p < 0.01). In terms of the safety, there were no statistically significant differences in the incidence of slow flow/no reflow, malignant arrhythmias, and hypotension within 24 hours post operation between the two groups (p > 0.05), and no major adverse cardiovascular event (MACE) occurred in either group during the postoperative follow-up period of 180 days (p > 0.05).

CONCLUSION

Intravenous administration of nicorandil in patients with STEMI during the perioperative percutaneous coronary intervention (PCI) period was effective in reducing the area of myocardial infarction and myocardial injury without increasing the incidence of malignant arrhythmias, hypotension, or composite cardiovascular events during the drug administration period.

Tongmai Yangxin pill reduces myocardial No-reflow via endothelium-dependent NO-cGMP signaling by activation of the cAMP/PKA pathway

ETHNOPHARMACOLOGICAL RELEVANCE

The Tongmai Yangxin pill (TMYX) is derived from the Zhigancao decoction recorded in Shang han lun by Zhang Zhongjing during the Han dynasty. TMYX is used for the clinical treatment of chest pain, heartache, and qi-yin-deficiency coronary heart disease. Previous studies have confirmed that TMYX can improve vascular endothelial function in patients with coronary heart disease by upregulating nitric oxide activity and then regulating vascular tension. Whether TMYX can further improve myocardial NR by upregulating NO activity and then dilating blood vessels remains unclear.

AIM OF THE STUDY

This study aimed to reveal whether TMYX can further improve myocardial NR by upregulating NO activity and then dilating blood vessels. The underlying cAMP/PKA and NO-cGMP signaling pathway-dependent mechanism is also explored.

MATERIALS AND METHODS

The left anterior descending coronary arteries of healthy adult male SD rats were ligated to establish the NR model. TMYX (4.0 g/kg) was orally administered throughout the experiment. Cardiac function was measured through echocardiography. Thioflavin S, Evans Blue, and TTC staining were used to evaluate the NR and ischemic areas. Pathological changes in the myocardium were assessed by hematoxylin-eosin staining. An automated biochemical analyzer and kit were used to detect the activities of myocardial enzymes and myocardial oxidants, including CK, CK-MB, LDH, reactive oxygen species, superoxide dismutase, malonaldehyde, and NO. The expression levels of genes and proteins related to the cAMP/PKA and NO/cGMP signaling pathways were detected via real-time fluorescence quantitative PCR and Western blot analysis, respectively. A microvascular tension sensor was used to detect coronary artery diastolic function in vitro.

RESULTS

TMYX elevated the EF, FS, LVOT peak, LVPWd and LVPWs values, decreased the LVIDd, LVIDs, LV-mass, IVSd, and LV Vols values, demonstrating cardio-protective effects, and reduced the NR and ischemic areas. Pathological staining showed that TMYX could significantly reduce inflammatory cell number and interstitial edema. The activities of CK, LDH, and MDA were reduced, NO activity was increased, and oxidative stress was suppressed after treatment with TMYX. TMYX not only enhanced the expression of Gs-α, AC, PKA, and eNOS but also increased the expression of sGC and PKG. Furthermore, TMYX treatment significantly decreased ROCK expression. We further showed that TMYX (25-200 mg/mL) relaxed isolated coronary microvessels.

CONCLUSIONS

TMYX attenuates myocardial NR after ischemia and reperfusion by activating the cAMP/PKA and NO/cGMP signaling pathways, further upregulating NO activity and relaxing coronary microvessels.

Coronary Endothelium No-Reflow Injury Is Associated with ROS-Modified Mitochondrial Fission through the JNK-Drp1 Signaling Pathway

Coronary artery no-reflow is a complex problem in the area of reperfusion therapy, and the molecular mechanisms underlying coronary artery no-reflow injury have not been fully elucidated. In the present study, we explored whether oxidative stress caused damage to coronary endothelial cells by inducing mitochondrial fission and activating the JNK pathway. The hypoxia/reoxygenation (H/R) model was induced in vitro to mimic coronary endothelial no-reflow injury, and mitochondrial fission, mitochondrial function, and endothelial cell viability were analyzed using western blotting, quantitative polymerase chain reaction (qPCR), enzyme-linked immunosorbent assay (ELISA), and immunofluorescence. Our data indicated that reactive oxygen species (ROS) were significantly induced upon H/R injury, and this was followed by decreased endothelial cell viability. Mitochondrial fission was induced and mitochondrial bioenergetics were impaired in cardiac endothelial cells after H/R injury. Neutralization of ROS reduced mitochondrial fission and protected mitochondrial function against H/R injury. Our results also demonstrated that ROS stimulated mitochondrial fission via JNK-mediated Drp1 phosphorylation. These findings indicate that the ROS-JNK-Drp1 signaling pathway may be one of the molecular mechanisms underlying endothelial cell damage during H/R injury. Novel treatments for coronary no-reflow injury may involve targeting mitochondrial fission and the JNK-Drp1 signaling pathway.

Effect of Danhong Injection () on Improving Coronary Microcirculation Injury after Percutaneous Coronary Intervention

OBJECTIVE

To explore the effectiveness of Danhong Injection () on improving microcirculatory injury after percutaneous coronary intervention (PCI) in patients with coronary heart disease (CHD).

METHODS

A randomized controlled trial was conducted and 90 patients were enrolled. A random sequence was generated using statistical analysis software. Patients with microcirculatory injuries after PCI were randomly divided into 3 groups for treatment (30 subjects in each group): Danhong Injection group: after PCI, Danghong Injections were given with intravenous administration with 40 mL twice a day for a week; statins intensive group: after PCI, atorvastatin calcium tablets were given oral medication with 80 mg once, and then atorvastatin 40 mg daily for 1 week; the control group: after PCI, atorvastatin calcium tablets were given oral medication with 10-20 mg daily for 1 week. The index of microcirculation resistance (IMR) was used to assess microcirculatory injury during PCI. The IMR of the target vessel was reexamined after 1 week of drug treatment.

RESULTS

After one week's drug treatment, IMR was significantly decreased in both statins intensive group and Danhong Injection group compared with the control group (P<0.01), but no difference was found between statins intensive group and Danhong injection group (14.03 ± 2.54 vs. 16.03 ± 5.72 U, P=0.080).

CONCLUSIONS

The efficacy of Danhong Injection is non-inferior to statin. Early use of Danhong Injection after PCI can effectively improve coronary microcirculation injury after PCI.