Role of NLRP3 inflammasome in therapeutic mild hypothermia post-treated myocardial ischemia-reperfusion rats / 临床麻醉学杂志

Objective To analyze the role of NOD-like receptor thermal protein domain associated protein 3(NLRP3)inflammasome in a therapeutic mild hypothermia(34℃)treated isolated rat myocardial ischemia-reperfusion model and explore its mechanism.Methods Sixty clean grade adult male SD rats,aged 7-10 weeks,weighing 250-300 g.Using a random number table method,the rats were divid-ed into five groups:blank control group(group S),myocardial ischemia-reperfusion group(group IR),34℃mild hypothermia post-treated myocardial ischemia-reperfusion group(group MH),34℃mild hypother-mia post-treated myocardial ischemia-reperfusion+3-TYP group(group HT),and 34℃mild hypothermia post-treated myocardial ischemia-reperfusion+3-TYP+MCC950 group(group HTM),12 rats in each group.Group S perfused the rat heart at 37℃with a balanced perfusion solution for 180 minutes.Group IR re-ceived balanced perfusion of the rat heart at 37℃for 30 minutes,followed by ischemia for 30 minutes and reperfusion with 37℃perfusion for 120 minutes.Group MH perfused the rat heart at 37℃for 30 minutes,followed by ischemia for 30 minutes and reperfusion with 34℃perfusion solution for 120 minutes.Group HT perfused the hearts of rats at 37℃for 30 minutes,followed by ischemia for 30 minutes,silent mating type information regulation 2 homolog 3(sirt3)inhibitor 3-TYP was added to the perfusate,and then per-fused at 34℃for 120 minutes.Group HTM perfused the hearts of rats at 37℃for 30 minutes,followed by ischemia for 30 minutes,sirt3 inhibitor 3-TYP and NLRP3 inhibitor MCC950 were added to the perfusate,and then perfused at 34℃for 120 minutes.The isolated heart was obtained 120 minutes after reperfusion,and the concentrations of IL-6 and IL-1β in the perfused cardiac fluid was measured using ELISA method,Western blot method for detecting the relative content of NLRP3 and sirt3 proteins in myocardial tissue,1%triphenyl tetrazolium chloride staining for calculating myocardial infarction area,and HE staining for observ-ing myocardial pathological changes.Results Compared with group S,HR were significantly slowed down,LVSP,±dp/dtmax were significantly decreased,and LVEDP were significantly increased 30,60,90,and 120 minutes after reperfusion,the concentrations of IL-6 and IL-1β in cardiac fluid leakage,and the per-centage of myocardial infarction area were significantly increased in groups IR,MH,HT,and HTM(P＜0.05),the content of sirt3 protein in myocardial tissue were significantly reduced,while the content of NLRP3 protein were significantly increased in groups IR,HT,and HTM(P＜0.05),the contents of sirt3 and NLRP3 protein in the myocardial tissue were significantly increased in group MH(P＜0.05).Com-pared with group IR,HR were significantly increased,LVSP,±dp/dtmax were significantly increased,and LVEDP were significantly decreased 30,60,90,and 120 minutes after reperfusion,the concentrations of IL-6 and IL-1β in cardiac fluid leakage and the percentage of myocardial infarction area were significantly decreased in groups MH and HTM(P＜0.05),the content of sirt3 protein in myocardial tissue was signifi-cantly increased,while the content of NLRP3 protein was significantly decreased in group MH(P＜0.05),the content of NLRP3 protein in myocardial tissue was significantly reduced in group HTM(P＜0.05).Compared with group MH,HR were significantly slowed down,LVSP,±dp/dtmax were significantly de-creased,and LVEDP were significantly increased 30,60,90,and 120 minutes after reperfusion,the con-centrations of IL-6 and IL-1β in cardiac fluid leakage,the percentage of myocardial infarction area,and the content of NLRP3 protein in myocardial tissue were significantly increased in group HT(P＜0.05),the content of sirt3 protein in myocardial tissue was significantly reduced in groups HT and HTM(P＜0.05).Compared with group HT,HR were significantly increased,LVSP,±dp/dtmax were significantly increased,and LVEDP were significantly decreased 30,60,90,and 120 minutes after reperfusion,the concentrations of IL-6 and IL-1β in cardiac fluid leakage,the percentage of myocardial infarction area,and the content of NLRP3 protein in myocardial tissue were significantly reduced in group HTM(P＜0.05).Conclusion Therapeutic mild hypothermia(34℃)can improve hemodynamic parameters of isolated hearts and reduce the concentrations of IL-6 and IL-1β,NLRP3 protein content in myocardial tissue,percentage of myocardial infarction area,improve myocardial pathological changes,and reduce myocardial ischemia-reperfusion injury in rats,the mechanism may be related to the mitochondrial mediated sirt3 pathway inhibiting the high expres-sion of inflammatory corpuscle NLRP3.

Research progress on the mechanism of several common sedatives and analgesics on cardiovascular pro-tection in patients with ischemic heart disease / 心血管康复医学杂志

Currently,living standard of people keeps growing,however,living habit changes follow economic development.Poor diet makes incidence rate of cardiovascular diseases increase year by year.Number of patients suffering from ischemic heart disease remains high in China every year,its characteristics of sudden onset,rapidly changing condition and high mor-tality bring huge shock on many families.The development of modern medicine has greatly reduced the risk of surgery for patients with ischemic heart disease(IHD).However,it is still necessary to master and understand the effects of sedatives and analgesics on cardiovascular system in order to perform successful completion of surgery on the premise of patient safe-ty.Propofol,sevoflurane,sufentanil,remifentanil and dexmedetomidine are commonly used sedatives and analgesics.The present article makes a review on the mechanism of above drugs on cardiovascular protection.

Trabecular Characteristics of Hypertrophic Cardiomyopathy Based on Cardiac Magnetic Resonance Fractal Analysis:A Preliminary Study / 中国医学影像学杂志

Purpose To evaluate the feasibility of cardiac magnetic resonance fractal analysis in evaluating left ventricular trabecular complexity in hypertrophic cardiomyopathy(HCM),and to study the degree of left ventricular trabecular complexity in HCM and the relationship between excessive trabecular complexity and cardiac function.Materials and Methods From August 2020 to December 2022,a total of 80 patients with HCM from the Second Affiliated Hospital of Nanchang University were retrospectively analyzed.Additionally,80 healthy volunteers were recruited as the control group.Left ventricular functional parameters and fractal dimension(FD)of left ventricular trabecular myocardium were measured.The differences of mean global FD,max basal FD and max apical FD were compared between the HCM group and the control group,the correlation between FDs and cardiac function parameters was evaluated.The diagnostic efficiency of mean global FD,max apical FD and max basal FD was analyzed via receiver operating characteristic curve.Results The mean global FD of HCM group was significantly higher than that of normal group,and the difference was statistically significant(1.303±0.047 vs.1.229±0.026;t=-12.387,P<0.001).Mean global FD showed the best performance in differentiating HCM from normal control group.The optimal cut-off value for the diagnosis of HCM was 1.251,with the area under curve of 0.933(95%CI 0.896-0.969).Mean global FD was positively correlated with maximum wall thickness and left ventricular mass index(r=0.686,0.687,P<0.001),and max apical FD was positively correlated with left ventricular ejection fraction(r=0.520,P<0.001).Conclusion The FD obtained by cardiac magnetic resonance fractal analysis technique is reproducible and has definite value in the diagnosis of HCM,with association with the structure and function of left heart.

Value of ultrasonic velocity vector imaging in assessing the motion abnormality of the myocardial segment of hyperthyroid heart disease / 中国医学装备

Objective:To explore the value of ultrasonic velocity vector imaging(VVI)in assessing motion abnormality of myocardial segment of hyperthyroid heart disease.Methods:A total of 76 patients with hyperthyroid heart disease who admitted to hospital from August 2019 to August 2021 were selected.According to the damage degree of ascending aorta of patients,30 patients whose inner diameter of ascending aorta was greater than 30 mm were included in the"inner diameter>30mm"group,and 46 patients whose inner diameter of ascending aorta was less than 30 mm were included in the"inner diameter<30mm"group.Additionally,40 healthy individuals who underwent physical examinations during the same period were selected as the healthy control group.All subjects underwent routine echocardiography examination,and the images were imported into the velocity vector imaging(VVI)workstation.And then,the clear and standard two-dimensional grayscale dynamic images were selected to conduct analysis.The left ventricle was tracked and analyzed,and the left ventricular long axis,the apical four chamber,and the velocity of reaching peak value,the time of 50%velocity and the time of 75%velocity of longitudinal myocardial movement of 18 segments of two chambers,as well as the mitral valve level of short axis,the velocity of reaching peak value of reaching peak value,the time of 50%velocity and the time of 75%velocity of radial myocardial movement of 12 segments of horizontal section of papillary muscle,of three cardiac cycles were stored and recorded.Results:There were significant differences in the time to peak of longitudinal contraction at the basal segment and middle segment of left ventricular lateral wall,and the basal segment of front wall,the basal segment,middle segment and apical segment of inferior wall,as well as the basal segment,middle segment and apical segment of posterior wall among three groups(F=45.02,23.19,8.70,19.82,16.17,18.07,36.85,48.65,36.64,P<0.05),respectively.There were significant differences in the velocity and time of reaching peak value of the radial contraction of the levels of papillary muscle and mitral valve of short axis of left ventricular inferior wall among the three groups(F=15.44,40.35,P<0.001),respectively.Conclusion:VVI technique can accurately detect the subtle changes of the synchronization of myocardial systolic motion of left ventricular short axis and long axis of patients with hyperthyroid heart disease,which has higher application value in assessing the abnormalities of myocardial segmental motion of patients with hyperthyroid heart disease.

The role of iron metabolism in aerobic exercise′s inhibition of cardiomyocyte apoptosis in atherosclerosis / 中华物理医学与康复杂志

Objective:To demonstrate any role of iron metabolism in the inhibition by aerobic exercise of myocardial apoptosis in atherosclerotic mice.Methods:Eight-week-old male ApoE -/- gene knockout mice were randomly divided into a control group, a model group and an aerobic exercise group, each of 9. A model of atherosclerosis was induced in the rats of the model and aerobic exercise groups by feeding them a " western" diet for 12 weeks. During that time the aerobic exercise group only was given aerobic exercise training. The control group was fed normal rat chow during that period. Myocardial apoptosis was detected using TUNEL staining, and the expression and localization of ferritin heavy chain 1 (FTH1) and glutathione peroxidase 4 (GPX4) in the myocardium used immunohistochemistry. Western blotting was applied to detect the FTH1 and GPX4 protein levels, and iron deposition in the myocardium was detected using Prussian blue staining. Iron, lipid peroxide malondialdehyde (MDA) and glutathione peroxidase (GSH-PX) in the myocardial tissue were also measured. Results:The TUNEL staining showed significant apoptosis in the model group. In the aerobic exercise group it was significantly less. There was obvious iron deposition in the myocardia of the model group, which was significantly reduced in the aerobic exercise group. The average FTH1 and GPX4 levels in the model group were lower than in the control group, and significantly elevated in the aerobic exercise group.in the aerobic exercise group than in the model group. Iron and MDA levels in the aerobic exercise group were significantly lower, on average, than among the model group, while that of GSH-PX was significantly higher.Conclusions:Aerobic exercise can significantly inhibit cardiomyocyte apoptosis in atherosclerotic mice. The mechanism may be closely related to better iron metabolism, reduced oxidative stress and the inhibition of iron overload.

Screening and experimental validation of hub genes for myocardial isch-emia-reperfusion injury based on bioinformatics / 中国病理生理杂志

AIM:Using bioinformatics analysis methods to identify the hub genes involved in myocardial isch-emia-reperfusion injury(MIRI).METHODS:Firstly,the rat MIRI related dataset GSE122020,E-MEXP-2098,and E-GEOD-4105 were downloaded from the database.Secondly,differentially expressed genes(DEGs)were screened from each dataset using the linear models for microarray data(limma)package,and robust DEGs were filtered using the robust rank aggregation(RRA)method.In addition,the surrogate variable analysis(SVA)package was used to merge all datas-ets into one,and merged DEGs were screened using the limma package.The common DEGs were obtained by taking the intersection of the two channels of DEGs.Next,the protein-protein interaction(PPI)network of common DEGs was con-structed,and the hub genes were identified using the density-maximizing neighborhood component(DMNC)algorithm.The receiver operating characteristic curve(ROC)was plotted to evaluate the diagnostic performance of the hub gene.Then,the mRNA and protein expression levels of hub genes were detected in the rat MIRI model,and the literature re-view analysis was carried out on the involvement of hub genes in MIRI.Finally,the gene set enrichment analysis(GSEA)was performed on hub gene to further reveal the possible mechanism in mediating MIRI.RESULTS:A total of 143 robust DEGs and 48 merged DEGs were identified.After taking the intersection of the two,48 common DEGs were obtained.In the PPI network of common DEGs,5 hub genes were screened out,namely MYC proto-oncogene bHLH transcription fac-tor(MYC),prostaglandin-endoperoxide synthase 2(PTGS2),heme oxygenase 1(HMOX1),caspase-3(CASP3),and plasminogen activator urokinase receptor(PLAUR).The ROC results showed that the area under the curve values for all hub genes were greater than 0.8.MYC,PTGS2,CASP3,and PLAUR showed high mRNA and protein expression in rat MIRI,while there was no difference in mRNA and protein expression for HMOX1.The literature review revealed that among the 5 hub genes,only PLAUR has not been reported to be involved in MIRI.The GSEA results for PLAUR indicat-ed that its functional enrichment mainly focused on pathways such as NOD-like receptor signaling pathway,P53 signaling pathway,Toll-like receptor signaling pathway,apoptosis,and fatty acid metabolism.CONCLUSION:MYC,PTGS2,CASP3,HMOX1,and PLAUR are involved in the pathological process of MIRI.PLAUR is a potential hub gene that can mediate MIRI by regulating pathways such as NOD like receptor signaling,P53 signaling,Toll like receptor signaling,cell apoptosis,and fatty acid metabolism.The results can provide reference for further investigation into the molecular mechanisms and therapeutic targets of MIRI.

Cardiac MR tissue tracking technique for quantitatively evaluating myocardial strain of cardiac amyloidosis patients / 中国介入影像与治疗学

Objective To observe the feasibility of cardiac MR tissue tracking(CMR-TT)technique for quantitatively evaluating myocardial strain of patients with myocardial amyloidosis(CA).Methods Cardiac MRI were collected from 20 patients of immunoglobulin amyloid light-chain CA(AL-CA,group A),20 cases of transthyretin CA(ATTR-CA,group B)and 20 healthy subjects(group C),and myocardial strain parameters were obtained using CMR-TT technique.Left ventricular cardiac function parameters were compared among 3 groups,so were strain parameters of each myocardial segment of left ventricle and global myocardium,including 3D longitudinal strain(LS),3D radial strain(RS)and 3D circumferential strain(CS).Results Compared with those in group C,significant differences of left ventricular cardiac function parameters were found in both group A and B(all P＜0.01),while no statistical difference was found between group A and B(all P＞0.05).Except for apical segment RS(P=0.81),strain parameters in group A and B were both lower than those in group C(all P＜0.01),while no significant difference was detected between group A and B(all P＞0.05).Conclusion CMR-TT technique could be used to quantitatively evaluate left ventricular myocardial strain of CA patients.

Preditores de Readmissão Hospitalar até 30 Dias de CRM em Banco de Dados Multicêntrico: Estudo de Coorte Transversal / Predictors of 30-Day Hospital Readmission Following CABG in a Multicenter Database: A Cross-Sectional Study

Resumo Fundamento: A análise de indicadores como taxa de readmissão hospitalar é crucial para aprimorar a qualidade dos serviços e gestão em processos hospitalares. Objetivo: Identificar as variáveis correlacionadas a readmissão hospitalar até 30 dias após cirurgia de revascularização miocárdica (CRM). Métodos: Estudo de coorte transversal no banco de dados Registro Paulista de Cirurgia Cardiovascular II (REPLICCAR II)(N=3.392), de junho de 2017 a junho de 2019. Avaliaram-se retrospectivamente 150 pacientes para identificar os fatores correlacionados a readmissão hospitalar até 30 dias após-CRM via regressão logística univariada e multivariada. As análises foram realizadas no software R, com significância de 0,05 e intervalos de confiança de 95%. Resultados: Cento e cinquenta pacientes foram readmitidos até 30 dias após a alta hospitalar de CRM (150/3.392, 4,42%) principalmente por infecções (mediastinite, ferida operatória e sepse) totalizando 52 casos (52/150, 34,66%), outras causas foram: complicações cirúrgicas (14/150, 9,33%) e pneumonia (13/150, 8,66%). Os preditores de readmissão identificados foram: O modelo de regressão multivariada apontou intercepto (OR: 1,098, p<0,00001), apneia do sono (OR: 1,117, p=0,0165), arritmia cardíaca (OR: 1,040, p=0,0712) e uso de balão intra-aórtico (OR: 1,068, p=0,0021) como preditores do desfecho, com uma AUC de 0,70. Conclusão: 4,42% dos pacientes foram readmitidos pós-CRM, principalmente por infecções. Fatores como apneia do sono (OR: 1,117, p=0,0165), arritmia cardíaca (OR: 1,040, p=0,0712) e uso de balão intra-aórtico (OR: 1,068, p=0,0021) foram preditores de readmissão, com uma discriminação de risco moderada (AUC: 0,70).

Abstract Background: The analysis of indicators such as hospital readmission rates is crucial for improving the quality of services and management of hospital processes. Objectives: To identify the variables correlated with hospital readmission up to 30 days following coronary artery bypass grafting (CABG). Methods: Cross-sectional cohort study by REPLICCAR II database (N=3,392) from June 2017 to June 2019. Retrospectively, 150 patients were analyzed to identify factors associated with hospital readmission within 30 days post-CABG using univariate and multivariate logistic regression. Analysis was conducted using software R, with a significance level of 0.05 and 95% confidence intervals. Results: Out of 3,392 patients, 150 (4,42%0 were readmitted within 30 days post-discharge from CABG primarily due to infections (mediastinitis, surgical wounds, and sepsis) accounting for 52 cases (34.66%). Other causes included surgical complications (14/150, 9.33%) and pneumonia (13/150, 8.66%). The multivariate regression model identified an intercept (OR: 1.098, p<0.00001), sleep apnea (OR: 1.117, p=0.0165), cardiac arrhythmia (OR: 1.040, p=0.0712), and intra-aortic balloon pump use (OR: 1.068, p=0.0021) as predictors of the outcome, with an AUC of 0.70. Conclusion: 4.42% of patients were readmitted post-CABG, mainly due to infections. Factors such as sleep apnea (OR: 1.117, p=0.0165), cardiac arrhythmia (OR: 1.040, p=0.0712), and intra-aortic balloon pump use (OR: 1.068, p=0.0021) were predictors of readmission, with moderate risk discrimination (AUC: 0.70).

Effects and mechanisms of Salvia miltiorrhiza Bunge extract on myocardial cell apoptosis in rat heart failure model

Purpose: This work aimed to investigate the effects of Tanshinone IIA (Tan IIA) on myocardial cell (MC) apoptosis in a rat model of heart failure (HF). Methods: Tan IIA was extracted from Salvia miltiorrhiza Bunge (SMB) using an ethanol reflux method. Fifty rats were randomly divided into five groups: sham (no treatment), mod (HF model establishment), low dose (LD: 0.1 mL/kg Tan IIA), medium dose (MD: 0.3 mL/kg Tan IIA), and high dose (HD: 0.5 mL/kg Tan IIA), with 10 rats in each group. The effects of different doses of Tan IIA on cardiac function, MC apoptosis, and the levels of proteins associated with the PI3K/Akt/mTOR signaling pathway were compared. Results: Mod group showed a significant decrease in systolic arterial pressure, mean arterial pressure, heart rate, left ventricular systolic pressure, left ventricular ejection fraction, left ventricular fractional shortening, and the levels of p-PI3K, p-Akt, and p-mTOR proteins versus sham group (p < 0.05). Additionally, the left ventricular end-diastolic diameter (LVIDd), end-systolic diameter, diastolic pressure, and MC apoptosis were significantly increased (p < 0.05). LD, MD, and HD groups exhibited significant improvements across various indicators of cardiac function and MC apoptosis versus mod group (p < 0.05). Conclusions: Tan IIA may improve cardiac function and inhibit MC apoptosis in rats with HF by modulating the PI3K/Akt/mTOR signaling pathway.

Impacto Clínico da Avaliação da Reserva de Fluxo Miocárdico na Identificação da Causa do Desconforto Torácico / Clinical Impact of Assessment of Myocardial Flow Reserve in Identifying the Cause of Chest Discomfort

Resumo Fundamento: Gama-câmaras com detectores de telureto-cádmio-zinco (CZT) permitiram a quantificação da reserva de fluxo miocárdico (RFM), podendo aumentar a acurácia da cintilografia miocárdica de perfusão (CMP) para detectar a causa do desconforto torácico. Objetivo: Avaliar o impacto clínico da RFM para detectar a causa do desconforto torácico. Métodos: 171 pacientes com desconforto torácico que foram submetidos a coronariografia ou angiotomografia de coronárias também realizaram CMP e RFM num intervalo de tempo <30 dias. As aquisições das imagens dinâmicas de repouso e estresse foram iniciadas simultaneamente à injeção de 99mTc sestamibi (10 e 30mCi, respectivamente), ambas com duração de onze minutos, seguidas imediatamente pela aquisição das imagens de perfusão durante 5 minutos. O estresse foi realizado com dipiridamol. Uma RFM global ou por território coronariano <2,0 foi classificada como anormal. Resultados: A idade média foi de 65,9±10 anos (60% do sexo feminino). A avaliação anatômica mostrou que 115 (67,3%) pacientes apresentavam obstrução coronariana significativa, sendo que, 69 apresentavam CMP anormal e 91 apresentavam RFM anormal (60,0% vs. 79,1%, p<0,01). Dentre os pacientes sem obstrução (56 - 32,7%), 7 tinham CMP anormais e 23 tinham RFM global reduzida. A realização da RFM identificou a etiologia do desconforto torácico em 114 pacientes enquanto a CMP identificou em 76 (66,7% vs. 44,4%, p<0,001). Conclusão: A RFM é uma medida fisiológica quantificável que aumenta o impacto clínico da CMP na detecção da causa do desconforto torácico através de uma maior acurácia para detecção de DAC obstrutiva e ainda possibilita identificar a presença de doença microvascular.

Abstract Background: Gamma cameras with cadmium-zinc telluride (CZT) detectors allowed the quantification of myocardial flow reserve (MBF), which can increase the accuracy of myocardial perfusion scintigraphy (MPS) to detect the cause of chest discomfort. Objective: To assess the clinical impact of MBF to detect the cause of chest discomfort. Methods: 171 patients with chest discomfort who underwent coronary angiography or coronary CT angiography also underwent MPS and MBF in a time interval of <30 days. The acquisitions of dynamic imaging of rest and stress were initiated simultaneously with the 99mTc injection sestamibi (10 and 30mCi, respectively), both lasting eleven minutes, followed by immediately acquiring perfusion images for 5 minutes. The stress was performed with dipyridamole. A global or per coronary territory MBF <2.0 was classified as abnormal. Results: The average age was 65.9±10 years (60% female). The anatomical evaluation showed that 115 (67.3%) patients had coronary obstruction significant, with 69 having abnormal MPs and 91 having abnormal MBF (60.0% vs 79.1%, p<0.01). Among patients without obstruction (56 - 32.7%), 7 had abnormal MPS, and 23 had reduced global MBF. Performing MBF identified the etiology of the chest discomfort in 114 patients while MPS identified it in 76 (66.7% vs 44.4%, p<0.001). Conclusion: MBF is a quantifiable physiological measure that increases the clinical impact of MPS in detecting the cause of chest discomfort through greater accuracy for detecting obstructive CAD, and it also makes it possible to identify the presence of the microvascular disease.

El fulcro cardíaco y su relación con el nódulo auriculoventricular / Cardiac Fulcrum, its Relationship with the Atrioventricular Node

RESUMEN Introducción. El estudio de la anatomía funcional del miocardio helicoidal continuo permite visualizar su inicio y fin en el nacimiento de los grandes vasos. En nuestras investigaciones siempre hemos considerado que debía tener un punto de unión que permitiera su rotación helicoidal para cumplir los movimientos fundamentales de acortamiento-torsión (sístole) y alargamiento-destorsión (succión). Una vez encontrado, se le llamó fulcro cardíaco. Objetivos. Esta investigación tiene como objeto describir y entender la interrelación entre el fulcro cardíaco y el nódulo auriculoventricular de Aschoff-Tawara Material y métodos. Se utilizaron 31 corazones procedentes de la morgue y del matadero: 17 correspondieron a bóvidos y 14 a seres humanos. Resultados. En nuestras investigaciones hemos demostrado que el soporte del miocardio, denominado fulcro cardíaco, que se localiza en el trayecto del segmento septal del anillo aórtico y se extiende desde el trígono izquierdo hasta el derecho por debajo del origen de la arteria coronaria derecha, es adyacente al nódulo auriculoventricular (AV). Otro aspecto importante de esta posición contigua es que el fulcro está rodeado, e incluso invadido, por un plexo nervioso interconectado con el nódulo. Conclusión. Esta descripción del fulcro cardíaco pondría fin al problema de la falta de apoyo del miocardio para cumplir su función de torsión/destorsión. La proximidad del fulcro al nódulo AV y la penetración de los plexos nerviosos en el apoyo indican la existencia de una unidad electromecánica, que hemos investigado en función de la anatomía helicoidal del corazón. Hemos comprobado una mejor estimulación cardíaca cuando el catéter se coloca en el infundíbulo ventricular derecho.

ABSTRACT Background. The functional anatomy of the helical, continuous myocardium allows envisioning that it initiates and ends at the origin of the great vessels. In our research, we have always considered that it should have a point of attachment to allow its helical rotation to fulfill the fundamental movements of shortening-torsion (systole) and lengthening-detorsion (suction), which once found, was called the cardiac fulcrum. Objectives. The research aims to describe the important aspect of understanding the interrelationship between the cardiac fulcrum and the Aschoff-Tawara atrioventricular node Material and Methods. A total of 31 hearts, arising from the morgue and slaughterhouse were used: 17 corresponded to bovids and 14 were human. Results. Our investigations have shown that the myocardial support termed cardiac fulcrum, located in the trajectory of the aortic annulus septal segment, extending from the left to the right trigone and below the origin of the right coronary artery, is adjacent to the AV node. Another important aspect of this contiguous position is that the fulcrum is surrounded, and even invaded, by a rich nervous plexus interconnected with the node. Conclusion. This description of the cardiac fulcrum would end the problem of lack of support of the myocardium to fulfill its function of torsion/detorsion. The proximity of the fulcrum to the AV node and the penetration of the nervous plexuses in the support suggest an electromechanical unit, which we have investigated according to the helical anatomy of the heart, establishing an improved cardiac stimulation with a catheter placed in the right ventricular outflow tract.

Cardiac Corpuscles: A "New" Morphofunctional Entity? / Corpúsculos Cardíacos: ¿Una "Nueva" Entidad Morfofuncional?

SUMMARY: The existence of "transitional muscular structures" between subendocardial branches (Purkinje fibers) and ventricular working muscle fibers (WF) was first described by the German anatomist, Kurt Goerttler, in 1964. He designated them as "subendocardial nucleus organs." He supposed such fibers functioned as mechanoreceptors, controlling of the intensity of contraction of the ventricular musculature. Brazilian anatomist Ferraz de Carvalho described similar structures in 1993. A thorough literature search failed to identify any other research articles confirming or denying their existence. The objective of this work was to find such structures in subendocardial ventricular walls in human hearts. We collected fifteen formalin-preserved hearts from the Anatomy Department of São Paulo University and sectioned the apical portions on the right and left ventricles according to method used by Goerttler. We utilized conventional histology (light microscopy- LM), scanning electron microscopy (SEM), and a new preservation method called micro- plastination (MP). At the anterior wall of the right ventricle in the subendocardial region between the interventricular septum and moderator band, we found several bundles of fusiform and helicoidal fibers of similar histology to the WF. The bundles measured between 400 and 1150 µm in length and were separated from adjacent muscular fibers by thin collagen fiber, thus acting as a "pseudo capsule." Some structures seemed to be linked to PF and were appeared to be lymphatic and blood vessels and nerves. We called those structures "cardiac corpuscles" (CC). The observation of the previously "unknown" CC in this initial study confirmed the previous descriptions and its discovery may contribute to new perspectives in the study of cardiac muscle structure and function.

La existencia de "estructuras musculares de transición" entre los ramos subendocárdicos (fibras de Purkinje) y las fibras musculares ventriculares activas(FMV) fue descrita por primera vez por el anatomista alemán Kurt Goerttler en 1964, quien las denominó "órganos del núcleo subendocárdico". Supuso que tales fibras funcionaban como mecanoreceptores, controlando la intensidad de la contracción de la musculatura ventricular. El anatomista brasileño Ferraz de Carvalho describió estructuras similares en 1993. Una búsqueda bibliográfica exhaustiva no logró identificar ningún otro artículo de investigación que confirmara o negara su existencia. El objetivo de este trabajo fue encontrar dichas estructuras en las paredes ventriculares subendocárdicas de corazones humanos. Recolectamos 15 corazones conservados en formalina del Departamento de Anatomía de la Universidad de São Paulo y seccionamos las porciones apicales de los ventrículos derecho e izquierdo según el método utilizado por Goerttler. Utilizamos histología convencional (microscopía de luz-LM), microscopía electrónica de barrido (SEM) y un nuevo método de conservación llamado microplastinación (MP). En la pared anterior del ventrículo derecho en la región subendocárdica entre el tabique interventricular y la banda moderadora, encontramos varios haces de fibras fusiformes y helicoidales de histología similar a la FMV. Los haces medían entre 400 y 1150 µm de longitud y estaban separados de las fibras musculares adyacentes por una fina fibra de colágeno, actuando así como una "pseudocápsula". Algunas estructuras parecían estar vinculadas a la fibras de purkinje y parecían ser vasos linfáticos, sanguíneos y nerviosos. Llamamos a esas estructuras "corpúsculos cardíacos" (CC). La observación del CC previamente "desconocido" en este estudio inicial confirmó las descripciones anteriores y su descubrimiento puede contribuir a nuevas perspectivas en el estudio de la estructura y función del músculo cardíaco.

Left Ventricular Non-Compaction Cardiomyopathy: Case Report and Review of Literature

Non-compaction cardiomyopathy (NCC) is characterized by trabeculations in either one or both ventricles. Clinical presentation is highly variable: dyspnea, palpitation, thromboembolic events, arrhythmia, or sudden cardiac death. There are currently no universally-accepted criteria for classifying and diagnosing left ventricular non-compaction (LVNC) cardiomyopathy. Transthoracic echocardiography (TTE) is the diagnostic exam of choice. The diagnosis is often missed or delayed because of a lack of knowledge about this uncommon disease. Progression of LVNC is highly variable and prognosis is very difficult to predict. We report a case of a 50-year-old female patient with a history of total thyroidectomy under hormonal supplementation who consults for dyspnea and paroxysmal palpitations revealing an isolated LVNC. This case emphasizes the importance of imaging techniques, which are, TTE and cardiac magnetic resonance imaging (MRI) in early diagnosis, management, and follow-up.

Como eu faço o strain longitudinal do ventrículo direito com softwares automatizados 2D e 3D / My approach to right ventricular longitudinal strain with automated 2D and 3D software

A análise da deformação miocárdica ventricular direita tem surgido como uma ferramenta diagnóstica importante na detecção de disfunção sistólica ventricular direita inicial não detectada pelas técnicas ecocardiográficas convencionais. Além disso, é capaz de trazer informações diagnósticas e prognósticas adicionais aos parâmetros tradicionais de avaliação da função sistólica ventricular direita em diversas patologias. O método ecocardiográfico de escolha para sua avaliação é o strain longitudinal derivado do speckletracking. Ele tem se mostrado mais sensível para pequenas mudanças na função sistólica quando comparado à excursão sistólica do plano do anel tricúspide, estudo da onda s´ ao Doppler tecidual do anel tricúspide e variação da área fracional do ventrículo direito. O avanço da inteligência artificial e a presença de softwares com análise automatizada entram neste cenário visando tornar a aplicabilidade do método mais simples, rápida e com menor variabilidade inter e intraobservador. O objetivo deste artigo de revisão é demonstrar o passo a passo da técnica, desde a otimização e aquisição de imagens até a interpretação dos resultados, com figuras ilustrativas de casos selecionados.(AU)

Right ventricular strain analysis has emerged as an important diagnostic tool in the detection of early right ventricular systolic dysfunction not detected by conventional echocardiography techniques. Furthermore, it is capable of providing additional diagnostic and prognostic information to the traditional parameters for evaluating right ventricular systolic function in various pathologies. The echocardiography method of choice for its assessment is longitudinal strain derived from speckletracking. This method has been shown to be more sensitive for small changes in systolic function when compared to tricuspid annular plane systolic excursion, tissue Doppler imaging of the tricuspid annular s' wave, and right ventricular fractional area change. Advances in artificial intelligence and software with automated analysis have been introduced to this scenario with the aim of making the method simpler and quicker to apply, with lower inter- and intra-observer variability. The objective of this review article is to demonstrate the technique step by step, from image optimization and acquisition to interpretation of results, with illustrative figures of selected cases.(AU)

Microcirculatory changes as a hallmark of aging in the heart and kidney / Cambios microcirculatorios como sello distintivo del envejecimiento en el corazón y riñón

SUMMARY: Changes in the microcirculation of multiple tissues and organs have been implicated as a possible mechanism in physiological aging. In particular, vascular endothelial growth factor is a secretory protein responsible for regulating angiogenesis via altering endothelial proliferation, survival, migration, extracellular matrix degradation and cell permeability. The aim of the present study was to evaluate the role of vascular endothelial growth factor in the progression of morphological alterations caused by physiological aging in the heart and kidney and to examine its relation to changes in capillary density. We used two age groups of healthy Wistar rats - 6- and 12-month- old. The expression of vascular endothelial growth factor was examined through immunohistochemistry and immunofluorescence and assessed semi-quantitatively. Changes in capillary density were evaluated statistically and correlated with the expression of vascular endothelial growth factor. We reported stronger immunoreactivity for vascular endothelial growth factor in the left compared to the right ventricle and also observed an increase in its expression in both ventricles in older animals. Contrasting results were reported for the renal cortex and medulla. Capillary density decreased statistically in all examined structures as aging progressed. The studied correlations were statistically significant in the two ventricles in 12-month-old animals and in the renal cortex of both age groups. Our results shed light on some changes in the microcirculation that take place as aging advances and likely contribute to impairment in the function of the examined organs.

Los cambios en la microcirculación de múltiples tejidos y órganos se han implicado como un posible mecanismo en el envejecimiento fisiológico. En particular, el factor de crecimiento endotelial vascular es una proteína secretora responsable de regular la angiogénesis mediante la alteración de la proliferación endotelial, la supervivencia, la migración, la degradación de la matriz extracelular y la permeabilidad celular. El objetivo del presente estudio fue evaluar el papel del factor de crecimiento del endotelio vascular en la progresión de las alteraciones morfológicas causadas por el envejecimiento fisiológico en el corazón y riñón y examinar su relación con los cambios en la densidad capilar. Utilizamos dos grupos de ratas Wistar sanas: 6 y 12 meses de edad. La expresión del factor de crecimiento del endotelio vascular se examinó mediante inmunohistoquímica e inmunofluorescencia y se evaluó semicuantitativamente. Los cambios en la densidad capilar se evaluaron estadísticamente y se correlacionaron con la expresión del factor de crecimiento del endotelio vascular. Informamos una inmunorreactividad más fuerte para el factor de crecimiento endotelial vascular en el ventrículo izquierdo en comparación con el derecho y también observamos un aumento en su expresión en ambos ventrículos en animales mayores. Se informaron resultados contrastantes para la corteza renal y la médula. La densidad capilar disminuyó estadísticamente en todas las estructuras examinadas a medida que avanzaba el envejecimiento. Las correlaciones estudiadas fueron estadísticamente significativas en los dos ventrículos en animales de 12 meses y en la corteza renal de ambos grupos de edad. Nuestros resultados arrojan luz sobre algunos cambios en la microcirculación que tienen lugar a medida que avanza el envejecimiento y probablemente contribuyan a un deterioro en la función de los órganos examinados.

Successful Correction of Postinfarction Interventricular Septum Rupture Diagnosed Online During the COVID-19 Pandemic (Clinical Case)

ABSTRACT Postinfarction interventricular septum defect is a rare, but very serious and sometimes fatal, complication of acute myocardial infarction. This article describes a clinical case of online diagnosis of a late-stage myocardial infarction and the subsequent successful endovascular repair of a postinfarction ventricular septum defect with a Myval™ occluder.

Bloodletting Acupuncture at Jing-Well Points Alleviates Myocardial Injury in Acute Altitude Hypoxic Rats by Activating HIF-1α/BNIP3 Signaling-Mediated Mitochondrial Autophagy and Decreasing Oxidative Stress / 中国结合医学杂志

OBJECTIVE@#To explore the protective effect and possible mechanisms of bloodletting acupuncture at Jing-well points (BAJP) pre-treatment on acute hypobaric hypoxia (AHH)-induced myocardium injury rat.@*METHODS@#Seventy-five rats were randomly divided into 5 groups by a random number table: a control group (n=15), a model group (n=15), a BAJP group (n=15), a BAJP+3-methyladenine (3-MA) group (n=15), and a BANA (bloodletting at nonacupoint; tail bleeding, n=15) group. Except for the control group, the AHH rat model was established in the other groups, and the corresponding treatment methods were adopted. Enzyme-linked immunosorbent assay (ELISA) was used to detect creatine kinase isoenzyme MB (CK-MB) and cardiac troponins I (CTnI) levels in serum and superoxide dismutase (SOD) and malondialdehyde (MDA) levels in myocardial tissue. Hematoxylin-eosin (HE) staining was used to observe myocardial injury, and terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) staining was used to observe cell apoptosis. Transmission electron microscopy detection was used to observe mitochondrial damage and autophagosomes in the myocardium. The mitochondrial membrane potential of the myocardium was analyzed with the fluorescent dye JC-1. Mitochondrial respiratory chain complex (complex I, III, and IV) activities and ATPase in the myocardium were detected by mitochondrial respiratory chain complex assay kits. Western blot analysis was used to detect the autophagy index and hypoxia inducible factor-1α (HIF-1α)/Bcl-2 and adenovirus E1B 19k Da-interacting protein 3 (BNIP3) signaling.@*RESULTS@#BAJP reduced myocardial injury and inhibited myocardial cell apoptosis in AHH rats. BAJP pretreatment decreased MDA levels and increased SOD levels in AHH rats (all P<0.01). Moreover, BAJP pretreatment increased the mitochondrial membrane potential (P<0.01), mitochondrial respiratory chain complex (complexes I, III, and IV) activities (P<0.01), and mitochondrial ATPase activity in AHH rats (P<0.05). The results from electron microscopy demonstrated that BAJP pretreatment improved mitochondrial swelling and increased the autophagosome number in the myocardium of AHH rats. In addition, BAJP pretreatment activated the HIF-1α/BNIP3 pathway and autophagy. Finally, the results of using 3-MA to inhibit autophagy in BAJP-treated AHH rats showed that suppression of autophagy attenuated the treatment effects of BAJP in AHH rats, further proving that autophagy constitutes a potential target for BAJP treatment of AHH.@*CONCLUSION@#BAJP is an effective treatment for AHH-induced myocardial injury, and the mechanism might involve increasing HIF-1α/BNIP3 signaling-mediated autophagy and decreasing oxidative stress.

Effect of hypothermic ischemia-reperfusion on the expression of Kir2.1 and CaMKⅡ in isolated rat atrial myocardium / 实用医学杂志

Objective To explore the molecular mechanism of prolonged atrial repolarization in rats with reperfusion atrial arrhythmia.Methods Sixteen Langendorff isolated heart perfusion models made by male SD rats were randomly divided into control group(group C,n = 8)and hypothermic ischemia-reperfusion group(group IR,n = 8).According to the occurrence of atrial arrhythmia after reperfusion,group IR was further subdivided into reperfusion non-atrial arrhythmia subgroup(group N-RAA)and reperfusion atrial arrhythmia subgroup(group R-AA).Group C was perfused with 37℃K-H solution for 120 min.In group IR,the isolated heart was perfused with 37℃K-H solution for 30 min and stopped,and the isolated heart was perfused with 4℃Thomas solution(20 mL/kg)for 60 mins.When the heart stopped for 30 mins,the isolated heart was perfused with a half dose of 4℃Thomas solution(10℃).During cardioplegia,the isolated heart was protected by low temperature Thomas solution(4℃),and then reperfused for 30 mins with 37℃K-H solution.The monophasic action potential(MAP)of the right atrium was recorded at balanced perfusion for 30 mins(T0),balanced perfusion for 105 mins in group C/reperfusion for 15 mins in group IR(T1)and balanced perfusion for 120 mins in group C/reperfusion for 30 min in group IR(T2);The duration of 50%and 90%repolarization of monophasic action potential(MAPD50 and MAPD90)was measured.After electrophysiological monitoring,the expression of Kir2.1 and CaMKⅡ in right atrium was detected by Western blot.Results Compared with T0,MAPD50 and MAPD90 at T1 and T2 were significantly prolonged in group R-AA(P<0.05),and MAPD90 at T1 and T2 in group R-NAA and group R-AA were significantly longer than those in group C(P<0.05).Compared with group R-NAA,MAPD50 and MAPD90 in group R-AA were significantly prolonged at T1 and T2(P<0.05).The results of Western blot showed that the expression of Kir2.1 in group R-NAA and group R-AA was significantly lower than that in group C(P<0.05),and that in group R-AA was significantly lower than that in group R-NAA(P<0.05).The expression of CaMKⅡ in group R-NAA and group R-AA was significantly higher than that in group C(P<0.05),and the expression of CaMKⅡ in group R-AA was significantly higher than that in group R-NAA.Conclusion The prolonged duration of atrial repolarization in rats with hypothermic ischemia-reperfusion atrial arrhythmia may be related to the down-regulation of Kir2.1 expression and the up-regulation of CaMKⅡ expression.

Influence of sodium-glucose cotransporter 2 inhibitor on myocardial metabolism in heart failure / 心血管康复医学杂志

Heart failure is the end stage of various heart disease.s Its occurrence and development involve complex patho-physiological process,among which abnormal myocardial metabolism is one of the factors that cannot be ignored.Sodium-glucose cotransporter 2 inhibitors(SGLT2i),as a novel oral hypoglycemic agent,plays a significant role in reducing the mortality of cardiovascular diseases and the rehospitalization rate of patients with heart failure,and regulating cardiac me-tabolism.The present review elaborates the metabolic changes of normal and failing hearts,and summarizes the effects of SGLT2i on myocardial metabolism in heart failure,aiming to guide clinical medication.