Estudo do efeito de estatinas e antiplaquetários na evolução do infarto agudo do miocárdio: uma abordagem metabolômica multiplataform / Effect of statins and antiplatelets in the evolution of acute myocardium infarction: a multiplatform metabolomics approach

O infarto agudo do miocárdio (IAM) é a maior causa de mortalidade no mundo. A oclusão coronária determina a necrose completa de cardiomiócitos (células musculares cardíacas) durante as primeiras horas do IAM. Porém, mesmo após a perda de massa de miocárdio viável cessar, a região infartada pode se expandir ou contrair no decorrer das primeiras semanas, afetando o prognóstico dos pacientes. Alguns tratamentos podem auxiliar na recuperação e melhoria do prognóstico desses pacientes, como o uso de estatinas e antiplaquetários, que quando utilizados em conjunto, proporcionam efeitos sinérgicos. O presente estudo investigou e comparou, através da óptica da metabolômica global multiplataforma, tratamentos concomitantes de estatinas (sinvastatina ou rosuvastatina) e antiplaquetários bloqueadores do receptor de ADP (clopidogrel ou ticagrelor), em pacientes que sofreram IAM. Foram coletadas amostras de plasma e urina de cerca 40 pacientes tratados com clopidrogrel e sinvastatina ou ticagrelor e rosuvastatina no Hospital São Paulo em diferentes períodos (basal, 1 mês e 6 meses após IAM). Amostras de plasma (basal e 1 mês) foram analisadas por RPLC-MS nos modos de ionização positivo e negativo, GC-MS e CEMS. Amostras de urina (basal, 1 mês e 6 meses) foram analisadas por RPLC-MS no modo de ionização positivo e HILIC-MS nos modos de ionização positivo e negativo. A abordagem metabolomica global multiplataforma evidenciou alterações no metabolismo de diferentes vias pelos dois tratamentos. Os dois tratamentos proporcionaram um efeito pronunciado no metabolismo de diferentes lipídios, como glicerolipídios, esfingolipídios, glicerofosfolipídios e ácidos graxos, sendo que a combinação rosuvastatina e ticagrelor resultou num efeito mais acentuado. Já o tratamento com clopidogrel e sinvastatina alterou de maneira mais pronunciada o metabolismo de aminoácidos ramificados e de acilcarnitinas de cadeia curta. Observou-se ainda a alteração de possíveis biomarcadores relatados na literatura como associados a problemas cardiovasculares, como hipoxantina, ácido 2-hidroxibutírico, algumas espécies de ceramidas, fosfatidilcolinas e acilcarnitinas de cadeia curta

cute myocardium infarction (AMI) is the main mortality cause in the world. The coronary occlusion determines the complete necrosis of cardiomyocytes (cardiac muscle cells) during the first hours of AMI. However, even after the loss of viable myocardial mass ceases, the infarcted area may still expand or contract during the first weeks after AMI, affecting the patient prognosis. Some treatments may assist patient recovery and improve prognostic, such as statins and antiplatelets which, when combined, provide synergic effects. This study investigated and compared, by untargeted multiplatform metabolomics, simultaneous treatments of statins (simvastatin or rosuvastatin) and ADP receptor antagonist antiplatelets (clopidogrel or ticagrelor) in patients that suffered AMI. Plasma and urine samples from around 40 patients treated with clopidogrel and simvastatin or ticagrelor and rosuvastatin were collected in Hospital Sao Paulo at different time points (basal, 1 month, 6 months after AMI). Plasma samples (basal and 1 month) were analyzed by RPLC-MS in positive and negative ionization modes, GC-MS and CE-MS. Urine samples (basal, 1 month, 6 months) were analyzed by RPLC-MS in positive ionization mode and by HILIC-MS in positive and negative ionization modes. The untargeted multiplatform metabolomics approach has shown that different metabolic pathways have been altered by the two treatments. Both treatments had a profound impact on the metabolism of different lipids, such as glycerolipids, sphingolipids, glycerophospholipids, and fatty acids. However, the combined treatment using rosuvastatin and ticagrelor impacted the most the lipid pathways. On the other hand, clopidogrel and simvastatin treatment affected more intensily the branched chain amino acids and short chain acylcarnitines metabolisms. Reported biomarkers in the literature related to cardiovascular diseases were also observed in this study, such as hypoxanthine, 2-hydroxybutyric acid, some species of ceramides, phosphatidylcholines and short chain acylcarnitines

Role of ACE and ACE-2 in abrogated cardioprotective effect of ischemic preconditioning in ovariectomized rat heart

Abstract Ischemic heart disease is the leading cause of death in postmenopausal women. The activity of heart ACE increases whereas the activity of ACE-2 decreases after menopause. The present study was designed to investigate the role of ACE and ACE-2 in the abrogated cardioprotective effect of IPC in OVX rat heart. The heart was isolated from OVX rat and mounted on Langendorff's apparatus for giving intermittent cycles of IPC. The infarct size was estimated using TTC stain, and coronary effluent was analyzed for LDH, CK-MB, and nitrite release. IPC induced cardioprotection was significantly attenuated in the ovariectomized rat heart as compared to the normal rat heart. However, this attenuated cardioprotection was significantly restored by perfusion of DIZE, an ACE-2 activator, and captopril, an ACE inhibitor, alone or in combination noted in terms of decrease in myocardial infarct size, the release of LDH and CK-MB, and also increase in the release of NO as compared to untreated OVX rat heart. Thus, it is suggested that DIZE and captopril, alone or in combination restore the attenuated cardioprotective effect of IPC in OVX rat heart which is due to an increase in ACE-2 activity and decrease in ACE activity after treatment.

Yixin Ningshen Tablet Alleviates Comorbidity of Myocardial Infarction and Depression by Enhancing Myocardial Energy Metabolism and Increasing Availability of Monoamine Neurotransmitter / 中国结合医学杂志

OBJECTIVE@#To investigate the therapeutic effect of Yixin Ningshen Tablet (YXNS) on comorbidity of myocardial infarction (MI) and depression in rats and explore the underlying mechanism.@*METHODS@#The Sprague-Dawley rats were randomly divided into 5 groups with 7 rats in each group according to their weights, including control, model, fluoxetine (FLXT, 10 mg/kg), low-dose YXNS (LYXNS, 100 mg/kg), and high-dose YXNS (HYXNS, 300 mg/kg) groups. All rats were pretreated with corresponding drugs for 12 weeks. The rat model of MI and depression was constructed by ligation of left anterior descending coronary artery and chronic mild stress stimulation. The echocardiography, sucrose preference test, open field test, and forced swim test were performed. Myocardial infarction (MI) area and myocardial apoptosis was also detected. Serum levels of interleukin (IL)-6, IL-1β, tumor necrosis factor-α (TNF-α), 5-hydroxytryptamine (5-HT), adrenocorticotrophic hormone (ACTH), corticosterone (CORT), and norepinephrine (NE) were determined by enzyme linked immunosorbent assay. The proteins of adenosine 5'-monophosphate -activated protein kinase (AMPK), p-AMPK, peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), and nuclear respiratory factor 1 (NRF1) in heart were detected by Western blot analysis. The expression levels of TNF-α, IL-6, indoleamine 2,3-dioxygenase (IDO1), kynurenine 3-monooxygenase (KMO), and kynureninase (KYNU) in hippocampus were detected by real-time quantitative polymerase chain reaction.@*RESULTS@#Compared with the model group, the cardiac function of rats treated with YXNS improved significantly (P<0.01). Meanwhile, YXNS effectively reduced MI size and cardiomyocytes apoptosis of rats (P<0.01 or P<0.05), promoted AMPK phosphorylation, and increased PGC-1α protein expression (P<0.01 or P<0.05). HYXNS significantly increased locomotor activity of rats, decreased the levels of TNF-α, IL-6 and IL-1β, and increased the serum levels of 5-HT, NE, ACTH, and CORT (all P<0.05). Moreover, HYXNS decreased the mRNA expressions of IDO1, KMO and KYNU (P<0.05).@*CONCLUSIONS@#YXNS can relieve MI by enhancing myocardial energy metabolism. Meanwhile, YXNS can alleviate depression by resisting inflammation and increasing availability of monoamine neurotransmitters. It may be used as a potential drug to treat comorbidity of MI and depression.

Lingbao Huxin Pill Alleviates Apoptosis and Inflammation at Infarct Border Zone through SIRT1-Mediated FOXO1 and NF- κ B Pathways in Rat Model of Acute Myocardial Infarction / 中国结合医学杂志

OBJECTIVE@#To investigate whether Lingbao Huxin Pill (LBHX) protects against acute myocardial infarction (AMI) at the infarct border zone (IBZ) of myocardial tissue by regulating apoptosis and inflammation through the sirtuin 1 (SIRT1)-mediated forkhead box protein O1 (FOXO1) and nuclear factor-κ B (NF-κ B) signaling pathways.@*METHODS@#Six-week-old Wistar rats with normal diet were randomized into the sham, the model, Betaloc (0.9 mg/kg daily), LBHX-L (0.45 mg/kg daily), LBHX-M (0.9 mg/kg daily), LBHX-H (1.8 mg/kg daily), and LBHX+EX527 (0.9 mg/kg daily) groups according to the method of random number table, 13 in each group. In this study, left anterior descending coronary artery (LADCA) ligation was performed to induce an AMI model in rats. The myocardial infarction area was examined using a 2,3,5-triphenyltetrazolium chloride solution staining assay. A TdT-mediated dUTP nick-end labeling (TUNEL) assay was conducted to assess cardiomyocyte apoptosis in the IBZ. The histopathology of myocardial tissue at the IBZ was assessed with Heidenhain, Masson and hematoxylineosin (HE) staining assays. The expression levels of tumor necrosis factor α (TNF-α), interleukin (IL)-6, IL-1 β, and intercellular adhesion molecule-1 were measured using enzyme-linked immunosorbent assays (ELISAs). The mRNA expressions of SIRT1 and FOXO1 were detected by real-time qPCR (RT-qPCR). The protein expressions of SIRT1, FOXO1, SOD2, BAX and NF- κ B p65 were detected by Western blot analysis.@*RESULTS@#The ligation of the LADCA successfully induced an AMI model. The LBHX pretreatment reduced the infarct size in the AMI rats (P<0.01). The TUNEL assay revealed that LBHX inhibited cardiomyocyte apoptosis at the IBZ. Further, the histological examination showed that the LBHX pretreatment decreased the ischemic area of myocardial tissue (P<0.05), myocardial interstitial collagen deposition (P<0.05) and inflammation at the IBZ. The ELISA results indicated that LBHX decreased the serum levels of inflammatory cytokines in the AMI rats (P<0.05 or P<0.01). Furthermore, Western blot analysis revealed that the LBHX pretreatment upregulated the protein levels of SIRT1, FOXO1 and SOD2 (P<0.05) and downregulated NF- κ B p65 and BAX expressions (P<0.05). The RT-qPCR results showed that LBHX increased the SIRT1 mRNA and FOXO1 mRNA levels (P<0.05). These protective effects, including inhibiting apoptosis and alleviating inflammation in the IBZ, were partially abolished by EX527, an inhibitor of SIRT1.@*CONCLUSION@#LBHX could protect against AMI by suppressing apoptosis and inflammation in AMI rats and the SIRT1-mediated FOXO1 and NF- κ B signaling pathways were involved in the cardioprotection effect of LBHX.

Quantification of DNA Damage in Different Tissues in Rats with Heart Failure / Quantificação de Dano em DNA em Diferentes Tecidos em Ratos com Insuficiência Cardíaca

Abstract Background: Chronic heart failure (CHF) is a complex syndrome which comprises structural and functional alterations in the heart in maintaining the adequate blood demand to all tissues. Few investigations sought to evaluate oxidative DNA damage in CHF. Objective: To quantify the DNA damage using the comet assay in left ventricle (LV), lungs, diaphragm, gastrocnemius and soleus in rats with CHF. Methods: Twelve male Wistar rats (300 to 330 g) were selected for the study: Sham (n = 6) and CHF (n = 6). The animals underwent myocardial infarction by the ligation of the left coronary artery. After six weeks, the animals were euthanized. It was performed a cell suspension of the tissues. The comet assay was performed to evaluate single and double strand breaks in DNA. Significance level (p) considered < 0.05. Results: The CHF group showed higher values of left ventricle end-diastolic pressure (LVEDP), pulmonary congestion, cardiac hypertrophy and lower values of maximal positive and negative derivatives of LV pressure, LV systolic pressure (p < 0.05). CHF group showed higher DNA damage (% tail DNA, tail moment and Olive tail moment) compared to Sham (p < 0.001). The tissue with the highest damage was the soleus, compared to LV and gastrocnemius in CHF group (p < 0.05). Conclusion: Our results indicates that the CHF affects all tissues, both centrally and peripherically, being more affected in skeletal muscle (soleus) and is positively correlated with LV dysfunction.

Resumo Fundamento: A insuficiência cardíaca crônica (ICC) é uma síndrome complexa que compreende alterações estruturais e funcionais no coração, mantendo demanda sanguínea adequada a todos os tecidos. Poucas investigações procuraram avaliar o dano oxidativo ao DNA na ICC. Objetivo: Quantificar o dano ao DNA utilizando o ensaio cometa no ventrículo esquerdo (VE), pulmões, diafragma, gastrocnêmio e sóleo em ratos com ICC. Métodos: Doze ratos Wistar machos (300 a 330 g) foram selecionados para o estudo: placebo (n = 6) e ICC (n = 6). Os animais foram submetidos a infarto do miocárdio através de ligadura da artéria coronária esquerda. Após seis semanas, os animais foram sacrificados. Foi realizada uma suspensão celular dos tecidos. O ensaio cometa foi realizado para avaliar as quebras de fita simples e dupla no DNA. Nível de significância (p) < 0,05. Resultados: O grupo ICC apresentou maiores valores de pressão diastólica final do ventrículo esquerdo (PDFVE), congestão pulmonar, hipertrofia cardíaca e menores valores de derivados máximos positivos e negativos da pressão do VE, pressão sistólica do VE (p < 0,05). O grupo ICC apresentou maior dano ao DNA (% de DNA da cauda, momento da cauda e momento da cauda de Olive) em comparação ao placebo (p < 0,001). O tecido com maior dano foi o sóleo, comparado ao VE e ao gastrocnêmio no grupo ICC (p < 0,05). Conclusão: Nossos resultados indicam que a ICC afeta todos os tecidos, de maneira central e periférica, sendo mais afetada no músculo esquelético (sóleo) e está positivamente correlacionada com a disfunção do VE.

Research Advances in Sympathetic Remodeling after Myocardial Infarction and Its Significance in Forensic Science / 法医学杂志

Sympathetic remodeling after myocardial infarction is presented as denervation, sympathetic nerve sprouting and sympathetic hyperinnervation, and is closely related to ventricular tachyarrhythmias and even sudden cardiac death at convalescence in patients with myocardial infarction. This article reviews the anatomic structure, morphology and functional remodeling of cardiac sympathetic nerve, as well as its role in healed myocardial infarction identification, which may provide references for forensic research.

Application of OCT in the Forensic Pathological Diagnosis of Coronary Artery Atherosclerosis and Myocardial Infarction / 法医学杂志

OBJECTIVES@#To investigate the value of optical coherence tomography （OCT） in the diagnosis of coronary atherosclerosis and myocardial infarction in forensic identification.@*METHODS@#OCT and hematoxylin-eosin （HE） examination were performed to examine the pathological samples of coronary artery and myocardial infarction in 5 cases of sudden coronary death. The morphological and local measurement indexes were compared.@*RESULTS@#In the OCT images, the layers of coronary artery could be distinguishably featured, and the atheroma plaques had a good morphological correspondence with HE slices. The normal myocardia in the OCT image showed weak light signals with high absorbance, while the fiber scar tissues in the myocardial infarction areas showed strong light signals with low absorbance. There were no significant differences on the fibrous cap thickness in coronary atherosclerotic plaques or intima-media thickness between the OCT images and the HE slices （P>0.05）. In the OCT images, the optical densities of the old myocardial infarction areas （1 226.24±622.66） and those of normal myocardia （3 707.90±962.98） were significantly different （ P<0.05）.@*CONCLUSIONS@#The OCT image has a good morphological consistency with HE slice, thus is expected to be the primary screening method for the forensic pathology examination of coronary artery atherosclerosis and myocardial infarction, which can help to improve the diagnostic accuracy.

Alprostadil attenuates myocardial ischemia/reperfusion injury by promoting antioxidant activity and eNOS activation in rats

Abstract Purpose: To investigate the effect of alprostadil on myocardial ischemia/reperfusion (I/R) in rats. Methods: Rats were subjected to myocardial ischemia for 30 min followed by 24h reperfusion. Alprostadil (4 or 8 μg/kg) was intravenously administered at the time of reperfusion and myocardial infarct size, levels of troponin T, and the activity of creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) in the serum were measured. Antioxidative parameters, nitric oxide (NO) content and phosphorylated endothelial nitric oxide synthase 3 (p-eNOS) expression in the left ventricles were also measured. Histopathological examinations of the left ventricles were also performed. Results: Alprostadil treatment significantly reduced myocardial infarct size, serum troponin T levels, and CK-MB and LDH activity (P<0.05). Furthermore, treatment with alprostadil significantly decreased malondialdehyde (MDA) content (P<0.05) and markedly reduced myonecrosis, edema and infiltration of inflammatory cells. Superoxide dismutase and catalase activities (P<0.05), NO level (P<0.01) and p-eNOS (P<0.05) were significantly increased in rats treated with alprostadil compared with control rats. Conclusion: These results indicate that alprostadil protects against myocardial I/R injury and that these protective effects are achieved, at least in part, via the promotion of antioxidant activity and activation of eNOS.

Vascular endothelial growth factor association with angiopoietin 1 promotes improvement in ventricular function after ischemic cardiomyopathy induced in mini pigs

Abstract Purpose: To investigate the safety and clinical, hemodynamic and tissue improvement ability in mini pigs undergoing cell and gene therapy for the treatment of acute myocardial infarction. Methods: Thirty-two mini pigs Br1 lineage, 12 months old, undergoing induction of acute myocardial infarction by occlusion of the diagonal branch of the paraconal coronary. They were divided into 4 groups: one control group and 3 treatment groups (cell therapy and gene cell therapy). Echocardiography reviews were performed on three occasions and histopathological analysis was performed after 4 weeks. Analysis of variance (ANOVA), Tukey and Wilcoxon tests, were performed. Results: Association of vascular endothelial growth factor (VEGF) with angiopoietin1 (Ang1) presented satisfactory results in the improvement of ventricular function following ischemic cardiomyopathy in mini pigs when compared to the results of the other treated groups. Conclusion: The therapy with VEGF and the combination of VEGF with Ang1, promoted recovered function of the myocardium, characterized by reduced akinetic area and induction of neovascularization.

Practical Implications of Myocardial Viability Studies / Implicações Práticas da Pesquisa de Viabilidade Miocárdica

Abstract Many non-invasive methods, such as imaging tests, have been developed aiming to add a contribution to existing studies in estimating patients' prognosis after myocardial injury. This prognosis is proportional to myocardial viability, which is evaluated in coronary artery disease and left ventricular dysfunction patients only. While myocardial viability represents the likelihood of a dysfunctional muscle (resulting from decreased oxygen supply for coronary artery obstruction), hibernation represents post-interventional functional recovery itself. This article proposes a review of pathophysiological basis of viability, diagnostic methods, prognosis and future perspectives of myocardial viability. An electronic bibliographic search for articles was performed in PubMed, Lilacs, Cochrane and Scielo databases, according to pre-established criteria. The studies showed the ability of many imaging techniques in detecting viable tissues in dysfunctional areas of left ventricle resulting from coronary artery injuries. These techniques can identify patients who may benefit from myocardial revascularization and indicate the most appropriate treatment.

Resumo Diversos métodos não invasivos, como novos exames de imagem, vem sendo aprimorados, a fim de somar esforços com os atuais em estimar o prognóstico de pacientes pós-injúria miocárdica. Este prognóstico é proporcional à viabilidade miocárdica, a qual tem sua avaliação reservada para pacientes portadores de doença arterial coronariana e insuficiência ventricular esquerda. Enquanto a viabilidade miocárdica se mostra como a capacidade de recuperação funcional do músculo com disfunção por redução de oxigênio fornecido por artérias coronárias obstruídas, a hibernação consiste na própria recuperação funcional após intervenções. Este artigo propõe uma revisão sobre as bases fisiopatológicas do processo de viabilidade, métodos diagnósticos disponíveis, prognóstico e perspectivas para o futuro acerca dessa condição. Realizou-se pesquisa de busca bibliográfica informatizada em bases eletrônicas de dados, como PubMed, Lilacs, Cochrane e Scielo, onde foram selecionados os estudos de acordo com critérios pré-determinados. Os estudos demonstram a capacidade de várias técnicas de imagem de identificar tecido viável em regiões disfuncionais do ventrículo esquerdo em decorrência de lesões em artérias coronárias. Estas técnicas podem identificar pacientes com potencial benefício da revascularização miocárdica e orientar o tratamento mais adequado.

Importância do diabetes mellitus na estratificação do risco de doença arterial coronária e risco cardiovascular global / Importance of diabetes mellitus in the risk stratification of coronary arterial disease and global cardiovascular risk

O diabetes mellitus é uma doença epidêmica. Os adultos portadores de diabetes têm taxas de doenças cardiovasculares duas a três vezes maiores do que aquelas observadas em adultos não diabéticos. O reconhecimento de que o diabetes é uma doença heterogênea em relação ao risco cardiovascular foi fundamental para a identificação correta dos indivíduos sob maior risco, os quais necessitam de tratamento farmacológico mais intensivo, e daqueles cujo risco é menor, em que o uso de medidas não farmacológicas isoladamente em uma fase inicial é opcional. Ferramentas para estratificação de risco mais precisas, uso apropriado de métodos de rastreamento de isquemia no paciente assintomático e indicação dos métodos de imagem são brevemente revisados neste capítulo. O tratamento de todos os fatores de risco inclui a moderna abordagem do paciente com diabetes, visando a redução de eventos macro e microvasculares. Descritores: Diabetes mellitus; Doença da artéria coronariana; Infarto do miocárdio; Acidente vascular cerebral.

Diabetes mellitus can be considered an epidemic disease. Adults with diabetes have two to three times higher rates of cardiovascular disease than those observed in non-diabetic adults. The recognition that diabetes is a heterogeneous disease in relation to cardiovascular risk was fundamental for the correct identification of individuals at higher risk, who require more intensive pharmacological intervention, and those at lower risk, where the use of non-pharmacological strategies alone in an initial phase is optional. More precise risk stratification tools, the appropriate use of screening methods for tracking ischemia in the asymptomatic patient, and the indication of imaging tests will be summarized in this review. Treatment based on global risk factor control includes the modern approach for the patient with diabetes, aiming at reducing both macro- and microvascular events.

The effect of periodontal therapy on neopterin and vascular cell adhesion molecule-1 levels in chronic periodontitis patients with and without acute myocardial infarction: a case-control study

Abstract The presence of neopterin in gingival crevicular fluid (GCF) is a marker for local and acute immune activation, and the presence of vascular cell adhesion molecule (VCAM-1) in GCF is accepted as a marker for chronic vascular inflammation. Objectives This study aimed to evaluate effects of periodontal treatment on GCF levels of neopterin and VCAM-1 in patients with chronic periodontitis (CP) with acute myocardial infarction (AMI) compared with systemically healthy CP patients. Material and methods Sixty subjects (20 CP patients with AMI, 20 healthy CP patients, and 20 healthy controls) were included. GCF samples were analyzed at baseline and after 3 and 6 months, and the probing pocket depth (PD), clinical attachment level (CAL), bleeding on probing, gingival (GI) and plaque (PI) indices were recorded. We determined neopterin and VCAM-1 levels (concentration and total amount) using enzyme-linked immunosorbent assay (ELISA). No significant differences were seen between the AMI+CP and CP groups for PI, GI, GCF levels of neopterin and VCAM-1 at baseline. Results The number of teeth with 5 mm≤CAL<7 mm and CAL≥7 mm were significantly increased in the AMI+CP group at baseline. There were no significant differences between the AMI+CP and CP for PI, CAL, GCF volumes, and the AMI+CP group had the highest clinical improvement in the number of teeth with 5 mm≤CAL<7 mm at the sixth month. There were significant positive correlations between clinical periodontal inflammation and the presence of neopterin and VCAM-1 in GCF prior to and following periodontal treatment, and between the GCF volume and clinical parameters. Conclusions Data suggest that the total amount and concentration of neopterin and VCAM-1 in GCF seemed to be closely associated with periodontal disease severity in CP patients with AMI. Moreover, the results of our study demonstrate that the past periodontal status is potentially correlated between groups, with similar periodontal disease severity.

Rupture of the myocardium in autopsied MI hearts / Ruptura do miocárdio em corações com IM autopsiados

Summary Although myocardial rupture occurs in only 2% to 4% of cases of acute myocardial infarction (AMI), there is a high mortality rate due to acute cardiogenic shock. We present the anatomopathological findings of three cases of myocardial rupture in autopsied hearts in the last 30 years, with a diagnosis of cardiac rupture in acute myocardial infarction. In these 30 years the percentage of AMI with myocardial rupture was 0.2%. Risk factors for post-AMI myocardial rupture include older age, atherosclerosis, diabetes mellitus and systemic arterial hypertension.

Resumo Embora a ruptura do miocárdio ocorra em apenas 2 a 4% dos casos de infarto agudo do miocárdio (IAM), está associada a alta mortalidade, principalmente em decorrência do estado de choque cardiogênico agudo. São apresentados os achados anatomopatológicos de três casos de ruptura do miocárdio de pacientes autopsiados nos últimos 30 anos, com diagnóstico de ruptura cardíaca em decorrência de IAM. Nesse período, a porcentagem de IAM com ruptura do miocárdio foi de 0,2%. Os fatores de risco para ruptura do miocárdio pós-IAM incluem idade avançada, arteriosclerose, diabetes mellitus e hipertensão arterial sistêmica.

Myocardial ischemic post-conditioning protects the lung against myocardial ischemia/reperfusion-induced damage by activating GSK-3

Abstract Purpose: To investigate whether modulating GSK-3β could attenuate myocardial ischemia reperfusion injury (MIRI) induced acute lung injury (ALI) and analyze the underlying mechanism. Methods: Male SD rats were subjected to MIRI with or without myocardial ischemic post-conditioning in the presence or absence of GSK-3β inhibitor. GSK-3β inhibitor was injected peritoneally 10min before MIRI. Lung W/D weight ratio, MPO, PMNs, histopathological changes, TUNEL, Bax, Bcl-2, IL-6, IL-8, IL-10, GSK-3β, and caspase-3 were evaluated in the lung tissues of all rats. Results: After MIRI, lung injury was significantly increased manifested as significant morphological changes and increased leukocytes in the interstitial capillaries, Lung W/D ratio, MPO, and PMN in BALF, which was associated with enhanced inflammation evidenced by increased expressions of IL-6, IL-8 and reduced expression of IL-10. MIRI significantly increased cell apoptosis in the lung as increased levels of apoptotosis, Bax, cleaved caspase-3, and reduced expression of Bcl-2 was observed, which was concomitant with reduced p-GSK-3β. All these changes were reversed/prevented by ischemic post-conditioning, while these beneficial effects of ischemic post-conditioning were abolished by GSK-3β inhibition. Conclusion: Myocardial ischemia reperfusion injury induces acute lung injury by induction of inflammation and cell apoptosis. Ischemic post-conditioning protects the lung from ALI following MIRI by increasing p-GSK-3β.

Infant acute myocarditis mimicking acute myocardial infarction

Myocarditis is an inflammatory disease of the myocardium with heterogeneous clinical manifestations and progression. In clinical practice, although there are many methods of diagnosis of acute myocarditis, the diagnosis remains an embarrassing dilemma for clinicians. The authors report the case of 9-month-old infant who was brought to the Pediatric Emergency Department with sudden onset dyspnea. Examination disclosed heart failure and resuscitation was undertaken. The electrocardiogram showed an ST segment elevation in the anterolateral leads with a mirror image. Cardiac enzyme tests revealed a significant elevation of troponin and creatine phosphokinase levels. A diagnosis of acute myocardial infarction was made, and heparin therapy was prescribed. The infant died on the third day after admission with cardiogenic shock. The autopsy showed dilatation of the ventricles and massive edema of the lungs. Histological examinations of myocardium samples revealed the presence of a marked lymphocytic infiltrate dissociating myocardiocytes. Death was attributed to acute myocarditis. The authors call attention to the difficulties of differential diagnosis between acute myocarditis and acute myocardial infarction especially in children, and to the important therapeutic implications of a correct diagnosis.

Sevoflurane preconditioning during myocardial ischemia-reperfusion reduces infarct size and preserves autonomic control of circulation in rats

ABSTRACT PURPOSE: To investigate the myocardial ischemia-reperfusion with sevoflurane anesthetic preconditioning (APC) would present beneficial effects on autonomic and cardiac function indexes after the acute phase of a myocardial ischemia-reperfusion. METHODS: Twenty Wistar rats were allocated in three groups: control (CON, n=10), myocardial infarction with sevoflurane (SEV, n=5) and infarcted without sevoflurane (INF, n=5). Myocardial ischemia (60 min) and reperfusion were performed by temporary coronary occlusion. Twenty-one days later, the systolic and diastolic function were evaluated by echocardiography; spectral analysis of the systolic arterial pressure (SAPV) and heart rate variability (HRV) were assessed. After the recording period, the infarct size (IS) was evaluated. RESULTS: The INF group presented greater cardiac dysfunction and increased sympathetic modulation of the SAPV, as well as decreased alpha index and worse vagal modulation of the HRV. The SEV group exhibited attenuation of the systolic and diastolic dysfunction and preserved vagal modulation (square root of the mean squared differences of successive R-R intervals and high frequency) of HRV, as well as a smaller IS. CONCLUSION: Sevoflurane preconditioning better preserved the cardiac function and autonomic modulation of the heart in post-acute myocardial infarction period.

Previous exercise training increases levels of PPAR-α in long-term post-myocardial infarction in rats, which is correlated with better inflammatory response

OBJECTIVE: Exercise is a protective factor for cardiovascular morbidity and mortality, with unclear mechanisms. Changing the myocardial metabolism causes harmful consequences for heart function and exercise contributes to metabolic adjustment modulation. Peroxisome proliferator-activated receptors (PPARs) are also myocardium metabolism regulators capable of decreasing the inflammatory response. We hypothesized that PPAR-α is involved in the beneficial effects of previous exercise on myocardial infarction (MI) and cardiac function, changing the expression of metabolic and inflammatory response regulators and reducing myocardial apoptosis, which partially explains the better outcome. METHODS AND RESULTS: Exercised rats engaged in swimming sessions for 60 min/day, 5 days/week, for 8 weeks. Both the exercised rats and sedentary rats were randomized to MI surgery and followed for 1 week (EI1 or SI1) or 4 weeks (EI4 or SI4) of healing or to sham groups. Echocardiography was employed to detect left ventricular function and the infarct size. Additionally, the TUNEL technique was used to assess apoptosis and immunohistochemistry was used to quantitatively analyze the PPAR-α, TNF-α and NF-κB antigens in the infarcted and non-infarcted myocardium. MI-related mortality was higher in SI4 than in EI4 (25% vs 12%), without a difference in MI size. SI4 exhibited a lower shortening fraction than EI4 did (24% vs 35%) and a higher apoptosis/area rate (3.97±0.61 vs 1.90±1.82) in infarcted areas (both p=0.001). Immunohistochemistry also revealed higher TNF-α levels in SI1 than in EI1 (9.59 vs 4.09, p<0.001) in infarcted areas. In non-infarcted areas, EI4 showed higher levels of TNF-α and positive correlations between PPAR-α and NF-κB (r=0.75, p=0.02), in contrast to SI4 (r=0.05, p=0.87). CONCLUSION: Previously exercised animals had better long-term ventricular function post-MI, in addition to lower levels of local inflammatory markers and less myocardial apoptosis, which seemed to be related to the presence of PPAR-α.