Optical coherence tomography analysis of lesion characteristics and thrombus types in non ST-segment elevation myocardial infarction patients.

The precise features of lesions in non-ST-segment elevation myocardial infarction (NSTEMI) patients with total occlusion (TO) of the infarct-related artery (IRA) are still unclear. This study employs optical coherence tomography (OCT) to investigate pathological features in NSTEMI patients with or without IRA TO and explores the relationship between thrombus types and IRA occlusive status. This was a single-center retrospective study. A total of 202 patients diagnosed with NSTEMI were divided into two groups: those with Thrombolysis In Myocardial Infarction (TIMI) flow grade 0 before percutaneous coronary intervention (PCI) (referred to as the TO group, n = 100) and those TIMI flow grade 1-3 (referred to as the Non-TO group, n = 102). Baseline characteristics, coronary angiography findings, and OCT results were collected. Multivariate logistic analysis identified factors influencing TO in NSTEMI. The category of NSTEMI was further subdivided based on the type of electrocardiogram (ECG) into two subgroups: ST segment unoffset myocardial infarction (STUMI) and ST segment depression myocardial infarction (STDMI). This division allows for a more specific classification of NSTEMI cases. The TO group had a younger age, higher male representation, more smokers, lower hypertension and cerebrovascular disease incidence, lower left ventricular ejection fraction (LVEF), and higher creatine kinase myocardial band (CKMB) and creatine kinase (CK) peak levels. In the TO group, LCX served as the main IRA (52.0%), whereas in the Non-TO group, LAD was the predominant IRA (45.1%). Compared to the Non-TO group, OCT findings demonstrated that red thrombus/mixed thrombus was more common in the TO group, along with a lower occurrence of white thrombus (p < 0.001). The TO group exhibited a higher prevalence of STUMI (p = 0.001), whereas STDMI was more commonly observed in the Non-TO group (p = 0.001). NSTEMI presents as STUMI and STDMI distinct entities. Red thrombus/mixed thrombus in IRA often indicates occlusive lesions with STUMI on ECG. White thrombus suggests non-occlusive lesions with STDMI on ECG.

Evaluation of an Optimized Workflow for the Radiofrequency Catheter Ablation of Paroxysmal Atrial Fibrillation.

BACKGROUND A significant number of atrial fibrillation (AF) recurrences occur after initial ablation, often due to pulmonary vein reconnections or triggers from non-pulmonary veins. MATERIAL AND METHODS Patients with paroxysmal AF who underwent radiofrequency catheter ablation for the first time were enrolled. Base on propensity score matching (1: 1 matching), 118 patients were selected for an optimized workflow for the radiofrequency catheter ablation of paroxysmal AF (OWCA) group and a conventional group. Comparative analysis of the acute and 12-month clinical outcomes was conducted. Moreover, an artificial intelligence analytics platform was used to evaluate the quality of pulmonary vein isolation (PVI) circles. RESULTS PVI was successfully achieved in all patients. Incidence of first-pass isolation of bilateral PVI circles was higher (P=0.009) and acute pulmonary vein reconnections was lower (P=0.027) in the OWCA group than conventional group. The OWCA group displayed a significant reduction in the number of fractured points (P<0.001), stacked points (P=0.003), and a greater proportion of cases in which the radiofrequency index achieved the target value (P=0.003). Additionally, the contact force consistently met the force over time criteria (P<0.001) for bilateral PVI circles in the OWCA group, accompanied by a shorter operation time (P=0.017). During the 12-month follow-up period, the OWCA group exhibited a higher atrial arrhythmia-free survival rate following the initial ablation procedure than did the conventional group. CONCLUSIONS The optimized workflow for radiofrequency catheter ablation of paroxysmal AF could play a crucial role in creating higher quality PVI circles. This improvement is reflected in a significantly elevated 12-month atrial arrhythmia-free survival rate.

Regulation of platelet activation and thrombus formation in acute non-ST segment elevation myocardial infarction: Role of Beclin1.

This study aims to investigate the mechanism of platelet activation-induced thrombosis in patients with acute non-ST segment elevation myocardial infarction (NSTEMI) by detecting the expression of autophagy-associated proteins in platelets of patients with NSTEMI. A prospective study was conducted on 121 patients with NSTEMI who underwent emergency coronary angiography and optical coherence tomography. The participants were divided into two groups: the ST segment un-offset group (n = 64) and the ST segment depression group (n = 57). We selected a control group of 60 patients without AMI during the same period. The levels of autophagy-associated proteins and the expression of autophagy-associated proteins in platelets were measured using immunofluorescence staining and Western blot. In NSTEMI, the prevalence of red thrombus was higher in the ST segment un-offset myocardial infarction (STUMI) group, whereas white thrombus was more common in the ST segment depression myocardial infarction (STDMI) group. Furthermore, the platelet aggregation rate was significantly higher in the white thrombus group compared with the red thrombus group. Compared with the control group, the autophagy-related protein expression decreased, and the expression of αIIbß3 increased in NSTEMI. The overexpression of Beclin1 could activate platelet autophagy and inhibit the expression of αIIbß3. The results suggested that the increase in platelet aggregation rate in patients with NSTEMI may be potentially related to the change in autophagy. And the overexpression of Beclin1 could reduce the platelet aggregation rate by activating platelet autophagy. Our findings demonstrated that Beclin1 could be a potential therapeutic target for inhibiting platelet aggregation in NSTEMI.

Performance of Subcutaneous Implantable Cardioverter Defibrillator (S-ICD) in Chinese Population with Primary Prevention Indications: A Prospective Observational Cohort Study.

BACKGROUND International studies have shown that use of a subcutaneous implantable cardioverter defibrillator (S-ICD) could reduce lead-related complications while maintaining adequate defibrillation performance; however, data from the Chinese population or other Asian groups are limited. MATERIAL AND METHODS SCOPE is a prospective, multicenter, observational cohort study. Two hundred patients with primary prevention indication for sudden cardiac death (SCD), who are candidates for S-ICD, will be enrolled. From the same population, another 200 patients who are candidates for transvenous implantable cardioverter defibrillator (TV-ICD) will be enrolled after being matched for age, sex, SCD high-risk etiology (ischemic cardiomyopathy, and non-ischemic cardiomyopathy, ion channel disease, and other) and atrial fibrillation in a 1: 1 ratio with enrolled S-ICD patients. All the patients will be followed for 18 months under standard of care. RESULTS The primary endpoint is proportion of patients free from inappropriate shock (IAS) at 18 months in the S-ICD group. The lower 95% confidence bound of the proportion will be compared with a performance goal of 90.3%, which was derived from the previous meta-analysis. The comparisons between S-ICD and TV-ICD on IAS, appropriate shock, and complications will be used as secondary endpoints without formal assumptions. CONCLUSIONS This is the first prospective multicenter study focusing on the long-term performance of S-ICD in a Chinese population. By comparing with the data derived from international historical studies and a matched TV-ICD group, data from SCOPE will allow for the assessment of S-ICD in the Chinese population in a contemporary real-world implantation level and programming techniques, which will help us to further modify the device implantation and programming protocol in this specific population in the future.

Relationship between thrombolysis in myocardial infarction blood flow before percutaneous coronary intervention and the morphological characteristics of culprit vessel plaques in patients with STEMI.

The present study aimed to investigate the relationship between morphological characteristics of culprit coronary plaques and thrombolysis in myocardial infarction (TIMI) blood flow grade in patients with ST-segment elevation myocardial infarction (STEMI). According to the TIMI blood flow of the culprit vessel before percutaneous coronary intervention (PCI), 222 patients with STEMI were divided into two groups: TIMI 0/1 group (n=164) and TIMI 2/3 group (n=58). The baseline characteristics, coronary angiographic findings and optical coherence tomography images were collected. Multivariate logistic regression analysis was used to identify factors independently associated with poor initial TIMI blood flow. Compared with TIMI 2/3 group, TIMI 0/1 group had a significantly smaller minimum lumen diameter, greater diameter stenosis and longer lesion length, a higher incidence of lipid plaque, larger lipid length, maximum lipid arc, lipid index and maximum cross-sectional area (CSA) of plaque rupture, as well as a higher prevalence of thin-cap fibroatheroma (TCFA) and healed plaque (P<0.05). Multivariate logistic analysis demonstrated that lipid plaque, lipid length, maximum lipid arc, lipid index, TCFA, maximum CSA of plaque rupture and healed plaque were significantly associated with poor initial TIMI blood flow (P<0.05). In conclusion, the present study revealed that the morphological characteristics of culprit coronary plaques (lipid plaque, lipid length, maximum lipid arc, lipid index, TCFA, maximum CSA of plaque rupture and healed plaque) are significantly associated with poor initial TIMI blood flow before PCI in patients with STEMI.

A novel stepwise catheter ablation method of the mitral isthmus for persistent atrial fibrillation: efficacy and reproducibility.

BACKGROUND: Ethanol infusion of the vein of Marshall (EI-VOM) has been widely used to facilitate mitral isthmus (MI) ablation. According to the literature, the success rate of achieving a bidirectional conduction block across the MI ranges from 51 to 96%, with no standardized strategy or method available for cardiac electrophysiologists. OBJECTIVES: This study aimed to introduce and evaluate a novel ablation method of MI. METHODS: Consecutive patients with persistent atrial fibrillation (PeAF) that underwent catheter ablation were included. The MI ablation procedure followed a stepwise approach. In step 1, ethanol infusion of the vein of Marshall (EI-VOM) was performed. In step 2, a "V-shape" endocardial linear ablation connecting the left inferior pulmonary vein (LIPV) to mitral annulus (MA) was performed. In step 3, earliest activation sites(EASs) near the ablation line were identified using activation mapping followed by reinforced ablation. In step 4, precise epicardial ablation was performed, with the catheter introduced into the coronary sinus(CS) to target key ablation targets (KATs). RESULTS: 135 patients with PeAF underwent catheter ablation with the stepwise ablation method adopted in 119 cases. Bidirectional conduction blocks were achieved in 117 patients (98.3%). The block rates of every step were 0%, 58.0%, 44.0%, and 92.9%, and the cumulative block rates for the four steps were 0%, 58.0%, 76.5%, and 98.3%, respectively. No patient experienced fatal complications. CONCLUSIONS: Our novel stepwise catheter ablation method for MI yielded a high bidirectional block rate with high reproducibility.

Association of GSDMD with microvascular-ischemia reperfusion injury after ST-elevation myocardial infarction.

Objectives: Little is known about the clinical prognosis of gasdermin D (GSDMD) in patients with ST-elevation myocardial infarction (STEMI). The purpose of this study was to investigate the association of GSDMD with microvascular injury, infarction size (IS), left ventricular ejection fraction (LVEF), and major adverse cardiac events (MACEs), in STEMI patients with primary percutaneous coronary intervention (pPCI). Methods: We retrospectively analyzed 120 prospectively enrolled STEMI patients (median age 53 years, 80% men) treated with pPCI between 2020 and 2021 who underwent serum GSDMD assessment and cardiac magnetic resonance (CMR) within 48 h post-reperfusion; CMR was also performed at one year follow-up. Results: Microvascular obstruction was observed in 37 patients (31%). GSDMD concentrations ≧ median (13 ng/L) in patients were associated with a higher risk of microvascular obstruction and IMH (46% vs. 19%, P = 0.003; 31% vs. 13%, P = 0.02, respectively), as well as with a lower LVEF both in the acute phase after infarction (35% vs. 54%, P < 0.001) and in the chronic phase (42% vs. 56%, P < 0.001), larger IS in the acute (32% vs. 15%, P < 0.001) and in the chronic phases (26% vs. 11%, P < 0.001), and larger left ventricular volumes (119 ± 20 vs. 98 ± 14, P = 0.003) by CMR. Univariable and multivariable Cox regression analysis results showed that patients with GSDMD concentrations ≧ median (13 ng/L) had a higher incidence of MACE (P < 0.05). Conclusions: High GSDMD concentrations in STEMI patients are associated with microvascular injury (including MVO and IMH), which is a powerful MACE predictor. Nevertheless, the therapeutic implications of this relation need further research.

The ratio of QRS/RV6-V1: a new electrocardiographic predictor of short- and long-term adverse clinical outcomes in patients with acute myocardial infarction combined with new-onset right bundle branch block.

Background: A few studies have focused on electrocardiography (ECG) parameters correlating with clinical prognosis in patients with acute myocardial infarction (AMI) combined with new-onset right bundle branch block (RBBB). Objective: To assess the prognostic value of a new ECG parameter, namely, the ratio of QRS duration/RV6-V1 interval (QRS/RV6-V1), in patients with AMI combined with new-onset RBBB. Materials and methods: A total of 272 AMI patients combined with new-onset RBBB who received primary percutaneous coronary intervention (P-PCI) were retrospectively enrolled in the study. First, the patients were divided into survival group and non-survival group. Demographic, angiographic, and ECG characteristics were compared between the two groups. Receiver operating characteristic (ROC) curve was used to screen the best ECG parameter for predicting 1-year mortality. Second, the ratio of QRS/RV6-V1, a continuous variable, was converted to the high ratio group and low ratio group according to the optimal cutoff value point determined by the X-tile software. We compared the patient's demographic, angiographic, and ECG characteristics, in-hospital major adverse cardiovascular events (MACE), and 1-year mortality between the two groups. Multivariate logistic and Cox regressions were used to evaluate whether the ratio of QRS/RV6-V1 was an independent prognostic factor of in-hospital MACE and 1-year mortality. Results: The ROC curve showed that the ratio of QRS/RV6-V1 had a higher value for predicting in-hospital MACE and 1-year mortality than the QRS duration, RV6-V1 interval, and RV1 interval. The patients in the high ratio group had significantly higher CK-MB peak and Killip class, lower ejection fraction (EF%), higher ratio of the left anterior (LAD) descending artery as infarct-related artery (IRA), and longer total ischemia time (TIT) than those in the low ratio group. The QRS duration was wider in the high ratio group than that in the low ratio group, whereas RV6-V1 was narrower in the high ratio group compared with that in the low ratio group. The in-hospital MACE rate (93.3% vs. 31.0%, p < 0.001) and 1-year mortality rate (86.7% vs. 13.2%, p < 0.001) in the high ratio group were higher than those in the low ratio group. The higher ratio of QRS/RV6-V1 was an independent predictor of in-hospital MACE (odds ratio, 8.55; 95% CI, 1.40-52.37; p = 0.02) after adjusting other confounders. Cox regression showed that the higher ratio of QRS/RV6-V1 predicted higher 1-year mortality of the patients with AMI combined with new-onset RBBB [hazard ratios (HR), 12.4; 95% CI, 7.26-21.22); p < 0.001] than the lower ratio of QRS/RV6-V1, and the HR still stayed at 2.21 even after a multivariable adjustment (HR, 2.21; 95% CI, 1.05-4.64); p = 0.037). Conclusion: According to the results of our study, the high ratio of QRS/RV6-V1 (>3.0) was a valuable predictor of short- and long-term adverse clinical outcomes in AMI patients combined with new-onset RBBB. The implications of the high ratio of QRS/RV6-V1 were severe ischemia and pseudo synchronization between bi-ventricle.

Bergapten inhibits NLRP3 inflammasome activation and pyroptosis via promoting mitophagy.

Inhibition of NLRP3 inflammasome activation produces potent therapeutic effects in a wide array of inflammatory diseases. Bergapten (BeG), a furocoumarin phytohormone present in many herbal medicines and fruits, exibits anti-inflammatory activity. In this study we characterized the therapeutic potential of BeG against bacterial infection and inflammation-related disorders, and elucidated the underlying mechanisms. We showed that pre-treatment with BeG (20 µM) effectively inhibited NLRP3 inflammasome activation in both lipopolysaccharides (LPS)-primed J774A.1 cells and bone marrow-derived macrophages (BMDMs), evidenced by attenuated cleaved caspase-1 and mature IL-1ß release, as well as reduced ASC speck formation and subsequent gasdermin D (GSDMD)-mediated pyroptosis. Transcriptome analysis revealed that BeG regulated the expression of genes involved in mitochondrial and reactive oxygen species (ROS) metabolism in BMDMs. Moreover, BeG treatment reversed the diminished mitochondrial activity and ROS production after NLRP3 activation, and elevated the expression of LC3-II and enhanced the co-localization of LC3 with mitochondria. Treatment with 3-methyladenine (3-MA, 5 mM) reversed the inhibitory effects of BeG on IL-1ß, cleaved caspase-1 and LDH release, GSDMD-N formation as well as ROS production. In mouse model of Escherichia coli-induced sepsis and mouse model of Citrobacter rodentium-induced intestinal inflammation, pre-treatment with BeG (50 mg/kg) significantly ameliorated tissue inflammation and injury. In conclusion, BeG inhibits NLRP3 inflammasome activation and pyroptosis by promoting mitophagy and maintaining mitochondrial homeostasis. These results suggest BeG as a promising drug candidate for the treatment of bacterial infection and inflammation-related disorders.

Proportioning Factors of Alkali-Activated Materials and Interaction Relationship Revealed by Response Surface Modeling.

Alkali-activated fly-ash-slag blending materials (AA-FASMs) are gradually being studied and applied more because of their good performance. There are many factors affecting the alkali-activated system, and the effect of single-factor variation on the performance of AA-FASM has been mostly reported; however, there is a lack of unified understanding of the mechanical properties and microstructure of AA-FASM under curing conditions and multiple-factor interaction. Therefore, this study investigated the compressive strength development and reaction products of alkali-activated AA-FASM under three curing conditions including seal (S), dry (D) and water saturation (W). Based on the response surface model, the relationship between the interaction of slag content (WSG), activator modulus (M) and activator dosage (RA) on its strength was established. The results showed that the maximum compressive strength of AA-FASM after 28 days of sealed curing was about 59 MPa, while the strengths of dry- and water-saturation-cured specimens decreased by 9.8% and 13.7%, respectively. The seal-cured samples also had the smallest mass change rate and linear shrinkage and the most compact pore structure. Due to the adverse effects from a too-high or too-low modulus and dosage of the activators, the shapes of upward convex, slope and inclined convex were under the interaction of WSG/M, WSG/RA and M/RA, respectively. The correlation coefficient R2 > 0.95 and p-value < 0.05 indicated that the proposed model could be used to predict strength development given the complex factors. Optimal proportioning and curing conditions were found to be WSG = 50%, M = 1.4, RA = 50% and sealed curing.

NEDD4 ameliorates myocardial reperfusion injury by preventing macrophages pyroptosis.

OBJECTIVES: The inflammatory cascade and cell death post-myocardial ischemia reperfusion (MI/R) are very complex. Despite the understanding that macrophage inflammation has a pivotal role in the pathophysiology of MI/R, the contribution of macrophage inflammatory signals in tailoring the function of vascular endothelium remains unknown. MATERIALS AND METHODS: In the present study, we analyzed the effects of NEDD4 on the NLRP3 inflammasome activation-mediated pyroptosis in vitro after an acute pro-inflammatory stimulus and in vivo in a MI/R mouse model. TTC and Evan's blue dye, Thioflavin S, immunohistochemistry staining, and ELISA were performed in wild-type and NEDD4 deficiency mice. THP-1 cells were transfected with si-NEDD4 or si-SF3A2. HEK293T cells were transfected with NEDD4 or SF3A2 overexpression plasmid. ELISA analyzed the inflammatory cytokines in the cell supernatant. The levels of NEDD4, SF3A2, and NLRP3/GSDMD pathway were determined by Western blot. Protein interactions were evaluated by immunoprecipitation. The protein colocalization in cells was monitored using a fluorescence microscope. RESULTS: NEDD4 inhibited NLRP3 inflammasome activation and pyroptosis in THP-1 cells treated with lipopolysaccharide (LPS) and nigericin (Nig). Mechanistically, NEDD4 maintained the stability of NLRP3 through direct interaction with the SF3A2, whereas the latter association with NLRP3 indirectly interacted with NEDD4 promoting proteasomal degradation of NLRP3. Deletion of NLRP3 expression further inhibited the caspase cascade to induce pyroptosis. Interestingly, inhibiting NLRP3 inflammasome activation in THP-1 cells could prevent cardiac microvascular endothelial cells (CMECs) injury. In addition, NEDD4 deficiency decreased animal survival and increased myocardial infarct size, no-reflow area, and promoted macrophages infiltration post-MI/R. CONCLUSIONS: NEDD4 could be a potential therapeutic target in microvascular injury following myocardial reperfusion. Video Abstract.

Validation of a predictive model for coronary artery disease in patients with diabetes.

BACKGROUND: No reliable model can currently be used for predicting coronary artery disease (CAD) occurrence in patients with diabetes. We developed and validated a model predicting the occurrence of CAD in these patients. METHODS: We retrospectively enrolled patients with diabetes at Henan Provincial People's Hospital between 1 January 2020 and 10 June 2020, and collected data including demographics, physical examination results, laboratory test results, and diagnostic information from their medical records. The training set included patients ( n  = 1152) enrolled before 15 May 2020, and the validation set included the remaining patients ( n  = 238). Univariate and multivariate logistic regression analyses were performed in the training set to develop a predictive model, which were visualized using a nomogram. The model's performance was assessed by area under the receiver-operating characteristic curve (AUC) and Brier scores for both data sets. RESULTS: Sex, diabetes duration, low-density lipoprotein, creatinine, high-density lipoprotein, hypertension, and heart rate were CAD predictors in diabetes patients. The model's AUC and Brier score were 0.753 [95% confidence interval (CI) 0.727-0.778] and 0.152, respectively, and 0.738 (95% CI 0.678-0.793) and 0.172, respectively, in the training and validation sets, respectively. CONCLUSIONS: Our model demonstrated favourable performance; thus, it can effectively predict CAD occurrence in diabetes patients.

Ablation index-guided high-power ablation for superior vena cava isolation in patients with atrial fibrillation.

Background: The strategy of ablation index (AI)-guided high-power ablation seems to be a novel strategy for performing pulmonary vein isolation (PVI). An AI-guided high-power ablation strategy was used in this study to determine whether superior vena cava isolation (SVCI) after PVI was feasible and safe for patients with AF. Methods: Data from 53 patients with AF were collected. Mapping and ablation of SVC were performed. The applied power was set at 45 W and the procedure was guided by AI. The SVC was divided into six segments in a cranial view. The RF applications and AI values in different segments were compared and analyzed. Using receiver operating characteristic (ROC) analysis, the diagnostic accuracy of AI value for predicting segment block was evaluated. Results: Electrical SVCIs were successfully achieved in all patients. SVCI was performed by segment ablation in most cases, with RF applications in different segments. The mean AI value in non-lateral walls was higher than that of the lateral wall (392 ± 28 vs. 371 ± 37, P < 0.001). Acutely blocked sites had significantly larger AI values compared with no-blocked sites (390 ± 30 vs. 343 ± 23, P < 0.001). The optimal AI cut-off value for non-lateral segments was 379 (sensitivity: 75.9%, specificity: 100%) and for lateral segments was 345 (sensitivity: 82.3%, specificity: 100%). Conclusion: The AI values were predictive of the acute conduction block of SVCI. With AI values of 345 and 379, respectively, conduction block was achieved in the lateral walls at a lower level than in the non-lateral walls.

The Differences in Clinical Characteristic and Outcomes of New Onset Typical versus Atypical Right Branch Bundle Block in Acute Myocardial Infarction.

Objective: The purpose of this study is to explore the clinical characteristics and estimate the new-onset atypical right branch bundle block (ATRBBB) predictive value in short-term and long-term mortality by comparing the typical right branch bundle block (TRBBB) subset in acute myocardial infarction (AMI) patients. Methods: A total of 224 AMI patients combined with new onset RBBB who received primary coronary angiography were included, being admitted to Henan Provincial People's Hospital in China from July 2010 to June 2021. Patients were divided into typical RBBB group (n = 104) and atypical RBBB group (n = 120). The differences in clinical characteristics between the two groups were analyzed. Logistic and Cox regression analysis were performed to identify independent predictors of in-hospital Major Adverse Cardiovascular Events (MACE). Result: The ATRBBB group had a higher proportion of smoking and alcohol consumption, higher body mass index, worse cardiac function (killip ≧ II proportion), higher peak value of CK-MB, lower LVEF%, longer total ischemia time, higher proportion of LAD (left anterior descending coronary artery) occlusion, and multivessel lesions, compared to the TRBBB group. The ATRBBB group had a higher proportion of in-hospital MACE and 1-year all-cause mortality compared to the TRBBB group. ATRBBB was an independent predictor of in-hospital MACE and 1-year mortality in patients with AMI combined with new onset RBBB. Conclusions: ATRBBB group had more serious clinical symptoms and clinical prognosis. New ATRBBB is an independent predictor of in-hospital MACE and 1-year death in patients with AMI combined with RBBB. If the infarct-related vessel was opened immediately, the evolution of TRBBB to ATRBBB may be avoided, leading to a better prognosis.

Cardiac sympathetic afferent ablation to prevent ventricular arrhythmia complicating acute myocardial infarction by inhibiting activated astrocytes.

Enhanced cardiac sympathetic afferent reflex (CSAR) contributes to ventricular arrhythmia (VA) after acute myocardial infarction (AMI). However, central regulation mechanisms remain unknown. The aim of this study was to investigate whether local cardiac sympathetic afferent ablation (LCSAA) could reduce VA by inhibiting activated astrocytes in the hypothalamus paraventricular (PVN) in an AMI rat model. The rats were randomly divided into AMI, AMI + BD (baroreceptor denervation), AMI + LCSAA and AMI + BD+ LCSAA groups. Before the generation of AMI, BD and (or) LCSAA were performed. At 24 h after AMI, the incidence and duration of VA in AMI + LCSAA group and AMI + BD + LCSAA group were significantly reduced than AMI group (P < 0.05). Furthermore, LCSAA significantly reduced GFAP (a marker for activated astrocytes) positive cells and their projections as well as the level of TNF-α and IL-6 in the PVN of AMI + LCSAA group and AMI + BD+ LCSAA group, along with the decrease of neuronal activation in PVN and sympathetic nerve activity (P < 0.05). but BD had no obvious difference between AMI + LCSAA and AMI + BD + LCSAA group (P > 0.05). Therefore, LCSAA could decrease sympathoexcitation and VA occurrence in AMI rats by inhibiting astrocyte and neuronal activation in the PVN. Our study demonstrates that activated astrocytes may play an important role on CSAR in AMI.

Relationship Between an Ischaemic J Wave Pattern and Ventricular Fibrillation in ST-Elevation Myocardial Infarction Patients.

BACKGROUND: This study determined the ischaemic J wave pattern associated with ventricular fibrillation (VF). METHODS: A total of 262 patients diagnosed with ST-elevation myocardial infarction (STEMI) were recruited from October 2017 to September 2020. All data were collected and analysed, including baseline characteristics, electrocardiogram (ECG), coronary angiography (CAG), and examination outcomes. RESULTS: There were 193 STEMI patients with J wave elevation but without an ischaemic J wave (NJ group) and 69 patients with an ischaemic J wave; the latter were then subgrouped into early repolarization pattern (ERP; n=62) and Brugada pattern groups (BrP [anteroseptal ERP]; n=7). Univariate and multivariate logistic regression analyses were used to clarify high-risk factors and characteristics of ischaemic J waves. Multivariate logistic regression analysis revealed that an ischaemic J wave (odds ratio [OR], 9.708; 95% CI, 2.570-36.664; P=0.01) independently predicted VF. In the subgroup analysis, BrP (OR, 31.214; 95% CI, 3.949-246.742; P=0.001), slur morphology of the ERP (OR, 8.15; 95% CI, 1.563-42.558; P<0.05), and the number of leads with an ischaemic J wave > 3 (OR, 16.174; 95% CI, 3.064-85.375; P=0.001) were significantly associated with VF occurrence after adjusting for multiple variables. CONCLUSION: An ischaemic J wave is an independent risk factor for VF in STEMI patients. BrP, slur morphology, and > 3 leads with an ischaemic J wave could increase the incidence of VF.

Ventricular tachycardia originating from the His bundle: A case report.

BACKGROUND: Ventricular tachycardia (VT) commonly occurs among patients with heart failure and can even cause sudden cardiac death. VT originating from the His bundle branch has been rarely reported. We present the case of a patient with VT from the His bundle branch. CASE SUMMARY: A 58-year-old female complained of paroxysmal palpitations and dizziness for approximately 6 mo. She had a history of fatty liver and cholecystitis, and carotid atherosclerosis could not be excluded from the ultrasound results. An evaluation of the electrocardiogram obtained after admission showed spontaneous conversion between two different morphologies. The possible electrophysiologic mechanism suggested that the dual-source VT originated from the same source, the His bundle branch. Finally, the His bundle branch was ablated, and a dual-chamber pacemaker was inserted into the patient's heart. No further VT occurred during the 3-year follow-up after hospital discharge. CONCLUSION: The diagnosis of VT originating from the His bundle is rare and difficult to establish. The results of this study showed VT originating from the His bundle based on a careful evaluation of the electrocardiogram, and the diagnosis was confirmed by an intracardiac electrophysiologic examination.

Beclin1 controls caspase-4 inflammsome activation and pyroptosis in mouse myocardial reperfusion-induced microvascular injury.

BACKGROUND: Myocardial reperfusion injury is often accompanied by cell death and inflammatory reactions. Recently, pyroptosis is gradually recognized as pivotal role in cardiovascular disease. However, little is known about the regulatory role of beclin1 in the control of caspase-4 activation and pyroptosis. The present study confirmed whether beclin1 regulates caspase-4 mediated pyroptosis and thereby protects Human Cardiac microvascular endothelial cells (HCMECs) against injury. METHODS: TTC and Evan's blue dye, western blot, immunofluorescence and immunohistochemistry staining were performed in wild mice and transgenic mice with overexpression of beclin 1(BECN1-Tg). CMECs were transfected with a beclin1 lentivirus. The cell cytotoxicity was analyzed by LDH-Cytotoxicity Assay Kit. The protein levels of autophagy protein (Beclin1, p62 and LC3II/LC3I) and caspase-4/GSDMD pathway were determined by western blot. Autophagic vacuoles in cells were monitored with RFP-GFP-LC3 using fluorescence microscope. RESULTS: I/R caused caspase-4 activity and gasdermin D expression increase in vivo and in vitro. Overexpression of beclin1 in heart tissue and CMECs suppressed the caspase-4 activity and decreased the levels of gasdermin D; meanwhile beclin1 overexpression also reduced IL-1ß levels, promoted autophagy (p62 expression was inhibited while LC3II expression was increased) in the heart and CMECs. Interestingly, beclin1 overexpression increased animal survival and attenuated myocardial infarct size (45 ± 6.13 vs 22 ± 4.37), no-reflow area (39 ± 5.22 vs 16 ± 2.54) post-myocardial ischemia reperfusion. CONCLUSIONS: Induction of beclin-1 signaling can be a potential therapeutic target in myocardial reperfusion-induced microvascular injury. Video Abstract.

Analysis of Characteristics of Patients with Non-ST-Segment Elevation Myocardial Infarction by Cardiac Magnetic Resonance Imaging.

BACKGROUND In this study, cardiac magnetic resonance imaging was used to investigate the characteristics of patients who have total coronary occlusion but manifest with non-ST-segment elevation myocardial infarction (NSTEMI), and we assessed the extent of infarct transmurality and myocardial necrosis size in NSTEMI patients. MATERIAL AND METHODS We enrolled all patients diagnosed at our hospital with subtotal or total occlusion of the culprit artery (TOCA), based on the coronary angiography, who successfully underwent PCI within 12 h of admission, and who had CMR imaging performed within 2 days after the PCI. RESULTS Based on 12-lead ECG findings, 48% of patients were categorized as having STEMI and 52% as having NSTEMI. TOCA was detected by coronary angiography in 43% of NSTEMI patients, and in 60% and 33% of normal ST segment and ST-segment depression MI patients, respectively. The transmural segments were found in 78% of STEMI patients and 31% of NSTEMI patients (P<0.05). Transmural infarction segments were found in 64% of NSTEMI patients with TOCA and in 8% of NTOCA patients (P<0.05). Moreover, the number of transmural segments in ST-segment depression MI patients was the lowest (P<0.05). Infarct size in STEMI patients was significantly larger than in patients with NSTEMI (P<0.05), whereas there was no statistically significant difference in patients with normal ST segment and ST-segment depression MI patients (P>0.05). CONCLUSIONS Identification TOCA by coronary angiography and transmural infarction by DE-MRI can be challenging in AMI patients with non-ST-segment elevation. In approximately 30% of non-ST-segment elevation MI patients, transmural infarction was detected by DE-MRI. Therefore, TOCA accompanied by transmural infarction in non-ST-segment-elevation MI patients is not uncommon.

Comparison of higher-power and conventional power ablation of atrial fibrillation using contact force-sensing catheters: a systematic review and meta-analysis.

BACKGROUND: Contact force-sensing catheters have been widely used in catheter ablation. During the past few decades, more attention has been paid on the technique of high-power ablation. The purpose of this meta-analysis is to compare the efficacy and safety of conventional power and high power on atrial fibrillation radiofrequency ablation by contact force-sensing catheters. METHODS: We identified studies through searching MEDLINE, Embase, the Web of Science, Scopus, and the Cochrane Library from inception up until July 2020. The primary outcomes were defined as recurrence of atrial tachyarrhythmia and complications. The secondary outcomes were acute reconnections of pulmonary veins (PVs), ablation time, and the total procedural time. RESULTS: Four nonrandomized, observational studies (nROS) were selected involving 231 patients with high-power ablation and 239 patients with conventional power ablation. There were insignificant differences in the recurrence rate of atrial tachyarrhythmia (14.2% versus 20.5%, OR: 0.64, 95%CI: 0.39 to 1.04, Z = 1.82, P = 0.07) and clinical complications (1.7% versus 2.5%, OR: 0.72, 95%CI: 0.21 to 2.47, Z = 0.51, P = 0.61) between high-power and conventional power ablation. However, compared with conventional power group, the high-power group had fewer acute PVs reconnections (P = 0.0001), shorter in ablation time (P < 0.0001), and the total procedural time (P < 0.0001). CONCLUSIONS: High-power ablation could not only ablate safely and efficiently but also reduce focal ablation time and total procedural time significantly.