[COVID-19 in patients with pre-existing cardiovascular disease: a series of cases during the fourth epidemiologic wave in Mexico City]. / COVID-19 en pacientes con afección cardiovascular preexistente: una serie de casos durante la cuarta ola epidemiológica en la Ciudad de México.

Objective: SARS-CoV-2 infection induces an immune response that causes excessive inflammation damaging cardiac tissue and vascular endothelium. The objective of this study is to review a series of cases of hospitalized patients with pre-existing cardiac disease to describe the clinical behavior and highlight the low frequency of morbidity and mortality. Method: Retrospective study of 17 patients with a confirmed diagnosis of COVID-19 by polymerase chain reaction test or antigen test, a history of cardiovascular disease with or without comorbidities, and a history of at least one dose of the vaccine for COVID-19, during the period between December 30, 2021 and March 17, 2022 at the Ignacio Chávez National Institute of Cardiology in Mexico City. Results: The most frequent cardiac pathology was acute myocardial infarction (31.25%) and the most common arrhythmia was atrial fibrillation (25%). The median number of days of hospital stay was 10 days (interquartile range: 4-14). Regarding the outcomes, 94% of the patients were discharged due to clinical improvement, and only one patient died during his hospitalization. Conclusions: It is crucial to continue investigating SARS-CoV-2 effects in patients pre-existing heart disease and in those with persistent symptoms after infection. This will allow the development of more effective strategies for the treatment and prevention of cardiovascular complications associated with COVID-19.

Objetivo: La infección por SARS-CoV-2 induce una respuesta inmunitaria que causa una inflamación excesiva dañando al tejido cardiaco y al endotelio vascular. El objetivo de este estudio es revisar una serie de casos de pacientes hospitalizados con patología cardiaca preexistente para describir el comportamiento clínico y resaltar la baja frecuencia de morbimortalidad. Método: Estudio retrospectivo de 17 pacientes con diagnóstico confirmado de COVID-19 mediante prueba de reacción en cadena de la polimerasa o prueba de antígenos, antecedente de enfermedad cardiovascular en presencia o no de comorbilidad, y antecedente de al menos una dosis de la vacuna para la COVID-19, durante el periodo entre el 30 de diciembre de 2021 y el 17 de marzo de 2022, en el Instituto Nacional de Cardiología Ignacio Chávez de la Ciudad de México. Resultados: La patología cardiaca previa más frecuente fue el infarto agudo de miocardio (31.25%), y la arritmia más común fue la fibrilación auricular (25%). La mediana de días de estancia hospitalaria fue de 10 (rango intercuartílico: 4-14). En cuanto a los desenlaces, el 94% de los pacientes fueron dados de alta por mejoría clínica y solo un paciente falleció durante su internamiento. Conclusiones: Es crucial continuar investigando y monitoreando los efectos del SARS-CoV-2 en los pacientes con enfermedades cardiacas preexistentes y en aquellos con síntomas persistentes después de la infección. Esto permitirá desarrollar estrategias más efectivas para el tratamiento y la prevención de las complicaciones cardiovasculares asociadas a la COVID-19.

The mitochondrial uncoupler 2,4-dinitrophenol modulates inflammatory and oxidative responses in Trypanosoma cruzi-induced acute myocarditis in mice.

By uncoupling oxidative phosphorylation, 2,4-dinitrophenol (DNP) attenuates reactive oxygen species (ROS) biosynthesis, which are known to aggravate infectious myocarditis in Chagas disease. Thus, the impact of DNP-based chemotherapy on Trypanosoma cruzi-induced acute myocarditis was investigated. C56BL/6 mice uninfected and infected untreated and treated daily with 100 mg/kg benznidazole (Bz, reference drug), 5 and 10 mg/kg DNP by gavage for 11 days after confirmation of T. cruzi infection were investigated. Twenty-four hours ​after the last treatment, the animals were euthanized and the heart was collected for microstructural, immunological and biochemical analyses. T. cruzi inoculation induced systemic inflammation (e.g., cytokines and anti-T. cruzi IgG upregulation), cardiac infection (T. cruzi DNA), oxidative stress, inflammatory infiltrate and microstructural myocardial damage in untreated mice. DNP treatment aggravated heart infection and microstructural damage, which were markedly attenuated by Bz. DNP (10 mg/kg) was also effective in attenuating ROS (total ROS, H2O2, and O2-), nitric oxide (NO), lipid (malondialdehyde - MDA) and protein (protein carbonyl - PCn) oxidation, TNF, IFN-γ, IL-10, and MCP-1/CCL2, anti-T. cruzi IgG, cardiac troponin I levels, as well as inflammatory infiltrate and cardiac damage in T. cruzi-infected mice. Our findings indicate that DNP aggravated heart infection and microstructural cardiomyocytes damage in infected mice. These responses were related to the antioxidant and anti-inflammatory properties of DNP, which favors infection by weakening the pro-oxidant and pro-inflammatory protective mechanisms of the infected host. Conversely, Bz-induced cardioprotective effects combined effective anti-inflammatory and antiparasitic responses, which protect against heart infection, oxidative stress, and microstructural damage in Chagas disease.

Fenofibrate Induces a Resolving Profile in Heart Macrophage Subsets and Attenuates Acute Chagas Myocarditis.

Chagas disease, caused by Trypanosoma cruzi, stands as the primary cause of dilated cardiomyopathy in the Americas. Macrophages play a crucial role in the heart's response to infection. Given their functional and phenotypic adaptability, manipulating specific macrophage subsets could be vital in aiding essential cardiovascular functions including tissue repair and defense against infection. PPARα are ligand-dependent transcription factors involved in lipid metabolism and inflammation regulation. However, the role of fenofibrate, a PPARα ligand, in the activation profile of cardiac macrophages as well as its effect on the early inflammatory and fibrotic response in the heart remains unexplored. The present study demonstrates that fenofibrate significantly reduces not only the serum activity of tissue damage biomarker enzymes (LDH and GOT) but also the circulating proportions of pro-inflammatory monocytes (CD11b+ LY6Chigh). Furthermore, both CD11b+ Ly6Clow F4/80high macrophages (MΦ) and recently differentiated CD11b+ Ly6Chigh F4/80high monocyte-derived macrophages (MdMΦ) shift toward a resolving phenotype (CD206high) in the hearts of fenofibrate-treated mice. This shift correlates with a reduction in fibrosis, inflammation, and restoration of ventricular function in the early stages of Chagas disease. These findings encourage the repositioning of fenofibrate as a potential ancillary immunotherapy adjunct to antiparasitic drugs, addressing inflammation to mitigate Chagas disease symptoms.

Chlamydia psittaci-related pleuro-myocarditis.

Chlamydia psittaci ‒ related community-acquired pneumonia associated to acute myocarditis was diagnosed in a young man with no medical history, and a professional exposition to birds. The diagnosis was confirmed with positive specific polymerase chain reaction in bronchoalveolar lavage. The patient was treated with spiramycin for two weeks with anti-inflammatory treatment for myocarditis for three months. Clinical and biological improvement was rapidly observed followed by normalization of electrocardiogram and chest CT scan. No relapse was reported for over a two-year follow-up.

Use of point-of-care ultrasound to assess the severity of scorpion stings in hospitalized patients.

INTRODUCTION: Scorpionism is a public health problem, especially in tropical regions. In Brazil, the prevalence of envenomation by scorpions is high, and the average national lethality is around 0.16 percent. The Tityus serrulatus scorpion is the primary species of medical importance. However, objective tools to predict and define the severity of these envenomations are lacking. MATERIALS AND METHODS: This was an observational study conducted among patients aged 0-19 years with scorpionism. Patients were admitted to a reference hospital between December 2020 and May 2022. Point-of-care ultrasound was performed within 24 hours of the scorpion sting. RESULTS: Forty-nine patients were included, with a median age of 3.6 (interquartile range 2.3-5.3) years and a predominance of females (51 percent). Fifteen patients (30.6 percent) presented major life-threatening signs, 32 (65.3 percent) minor systemic manifestations, and two (4.1 percent) only local manifestations. Left ventricular dysfunction was identified in 13 patients (26.5 percent). Ten patients (20.4 percent) presented pattern B (visualization of three or more B lines in the evaluated quadrant) in at least one lung window. The sensitivity and specificity of cardiac and pulmonary ultrasound to identify the most severely ill patients were 86 percent and 94 percent, respectively. DISCUSSION: The changes found on point-of-care ultrasound were associated with life-threatening signs. All patients with class III envenomation were referred to the intensive care unit, showing the importance of early identification of this subgroup. The main limitations were the small sample size and the fact that admission to intensive care was not based on systematic criteria. CONCLUSIONS: Point-of-care ultrasound is able to identify early signs of pulmonary congestion and heart failure in scorpionism. It can be useful for the objective selection of patients who are at a higher risk of complications and death and who require intensive support; it may also be valuable for periodic reassessments. Point-of-care ultrasound is a valuable tool for identifying and monitoring severe cases of scorpionism.

Fatal Myocarditis following COVID-19 mRNA Immunization: A Case Report and Differential Diagnosis Review.

Carditis in childhood is a rare disease with several etiologies. We report a case of infant death due to pericarditis and myocarditis after the mRNA vaccine against COVID-19 (COVIDmRNAV). A 7-year-old male child received the first dose of the COVIDmRNAV and presented with monoarthritis and a fever non-responsive to oral antibiotics. The laboratory investigation showed signs of infection (leukocytosis, high levels of c-reactive protein). His condition rapidly deteriorated, and the patient died. The autopsy identified pericardial fibrin deposits, hemorrhagic areas in the myocardium, and normal valves. A diffuse intermyocardial inflammatory infiltrate composed of T CD8+ lymphocytes and histiocytes was identified. An antistreptolysin O (ASO) dosage showed high titers. The presence of arthritis, elevated ASO, and carditis fulfills the criteria for rheumatic fever. However, valve disease and Aschoff's nodules, present in 90% of rheumatic carditis cases, were absent in this case. The temporal correlation with mRNA vaccination prompted its inclusion as one of the etiologies. In cases of myocardial damage related to COVID-19mRNAV, it appears to be related to the expression of exosomes and lipid nanoparticles, leading to a cytokine storm. The potential effects of the COVID-19mRNAV must be considered in the pathogenesis of this disease, whether as an etiology or a contributing factor to a previously initiated myocardial injury.

[Fulminant myocarditis in a patient with a history of autoimmune hepatitis]. / Miocarditis fulminante en paciente con antecedente de hepatitis autoinmune.

Myocarditis is an inflammatory disease of the cardiac tissue of variable etiology, both infectious and non-infectious. Its presentation can range from asymptomatic to fulminant forms. We present the case of a 24-year-old male patient with a history of autoimmune hepatitis in compensated cirrhotic phase. He consulted for dyspnea of 15 days evolution. He had presented gastrointestinal symptoms one month prior to the consultation. Physical examination revealed signs of heart failure. Laboratory examination showed elevated cardiac biomarkers and acute on chronic hepatic insufficiency. A transthoracic echocardiogram showed severe global biventricular dysfunction. The diagnostic hypotheses were cardiac involvement due to reactivation of autoimmune disease versus viral myocarditis. An MRI was performed which confirmed very severe ventricular dysfunction and late gadolinium enhancement suggestive of myocarditis. It was indicated treatment with methylprednisolone pulses. On the first day of hospitalization he evolved with clear signs of cardiogenic shock and ventricular arrhythmia refractory to medical treatment. After an exhaustive multidisciplinary evaluation, which was difficult due to his clinical condition, the possibility of a heart transplant was considered. Extracorporeal membrane oxygenation (ECMO) support was established as a bridge to transplantation. On the seventh day after ECMO, and after great improvement of the hepatogram parameters, the patient received a heart transplant. He had good postoperative evolution. However, he died two months after the transplant due to an opportunistic infection. The results of the biopsy of the explanted organ confirmed the diagnosis of lymphocytic myocarditis.

La miocarditis es una enfermedad inflamatoria del tejido cardíaco de etiología variable, infecciosa o no infecciosa. Su presentación va desde formas asintomáticas hasta fulminantes. Se presenta el caso de un varón de 24 años, con antecedente de hepatitis autoinmune, en fase cirrótica compensada. Consultó por disnea de 15 días de evolución. Presentó cuadro gastrointestinal un mes previo a la consulta. El examen físico reveló signos de sobrecarga hídrica. El laboratorio informó elevación de biomarcadores cardiacos, insuficiencia hepática aguda sobre crónica y graves trastornos de coagulación. Se realizó un ecocardiograma transtorácico que evidenció disfunción biventricular grave global, con adelgazamiento de las paredes. Las hipótesis diagnósticas fueron compromiso cardíaco por reactivación de enfermedad autoinmune versus miocarditis viral. Se realizó una resonancia magnética que confirmó la disfunción ventricular grave en la que se observó realce tardío de gadolinio sugestivo de miocarditis. Se indicó tratamiento con pulsos de metilprednisolona. El primer día de la internación evolucionó con signos de shock cardiogénico y arritmia ventricular refractaria al tratamiento. Posteriormente a una evaluación multidisciplinaria exhaustiva y dificultosa por el estado clínico, se planteó la posibilidad de un trasplante cardiaco. Se instauró soporte con membrana de oxigenación extracorpórea (ECMO) como puente al trasplante. Al séptimo día de colocado el ECMO, y luego de gran mejoría de los parámetros del hepatograma, recibió un trasplante cardíaco. Tuvo buena evolución postoperatoria, sin embargo, a los dos meses falleció por una infección oportunista. Los resultados de la biopsia del órgano explantado confirmaron el diagnóstico de miocarditis linfocítica.

Previous cardiovascular injury is a prerequisite for immune checkpoint inhibitor-associated lethal myocarditis in mice.

AIMS: Immune checkpoint inhibitors (ICIs) are antineoplastic drugs designed to activate the immune system's response against cancer cells. Evidence suggests that they may lead to immune-related adverse events, particularly when combined (e.g., anti-CTLA-4 plus anti-PD-1), sometimes resulting in severe conditions such as myocarditis. We aimed to investigate whether a previously sustained cardiac injury, such as pathological remodelling due to hypertension, is a prerequisite for ICI therapy-induced myocarditis. METHODS: We evaluated the cardiotoxicity of ICIs in a hypertension (HTN) mouse model (C57BL/6). Weekly doses were administered up to day 21 after the first administration. Our analysis encompassed the following parameters: (i) survival and cardiac pathological remodelling, (ii) cardiac function assessed using pressure-volume (PV)-loops, with brain natriuretic peptide (BNP) serving as a marker of haemodynamic dysfunction and (iii) cardiac inflammation (cytokine levels, infiltration, and cardiac antigen autoantibodies). RESULTS: After the first administration of ICI combined therapy, the treated HTN group showed a 30% increased mortality (P = 0.0002) and earlier signs of hypertrophy and pathological remodelling compared with the untreated HTN group. BNP (P = 0.01) and TNF-α (<0.0001) increased 2.5- and 1.7-fold, respectively, in the treated group, while IL-6 (P = 0.8336) remained unchanged. Myocarditis only developed in the HTN group treated with ICIs on day 21 (score >3), characterised by T cell infiltration and increased cardiac antigen antibodies (86% showed a titre of 1:160). The control group treated with ICI was unaffected in any evaluated feature. CONCLUSIONS: Our findings indicate that pre-existing sustained cardiac damage is a necessary condition for ICI-induced myocarditis.

Fulminant Necrotizing Eosinophilic Myocarditis Successfully Treated With Veno-Arterial Extracorporeal Membrane Oxygenation and High-Dose Steroids

Abstract Fulminant necrotizing eosinophilic myocarditis (FNEM) is a rare form of EM characterized by biventricular heart failure with hemodynamic deterioration, often requiring inotropes or mechanical circulatory support. Here, we report a case of a 43-year-old healthy woman with FNEM who was admitted with acute heart failure that rapidly progressed to cardiogenic shock and electrical storm, culminating in cardiac arrest. Early diagnosis and prompt administration of corticosteroids in combination with veno-arterial extracorporeal membrane oxygenation allowed complete recovery of biventricular systolic function.

Miocarditis fulminante en paciente con antecedente de hepatitis autoinmune / Fulminant myocarditis in a patient with a history of autoimmune hepatitis

Resumen La miocarditis es una enfermedad inflamatoria del tejido cardíaco de etiología variable, infecciosa o no in fecciosa. Su presentación va desde formas asintomáticas hasta fulminantes. Se presenta el caso de un varón de 24 años, con antecedente de hepatitis autoinmune, en fase cirrótica compensada. Consultó por disnea de 15 días de evolu ción. Presentó cuadro gastrointestinal un mes previo a la consulta. El examen físico reveló signos de sobrecarga hídrica. El laboratorio informó elevación de biomar cadores cardiacos, insuficiencia hepática aguda sobre crónica y graves trastornos de coagulación. Se realizó un ecocardiograma transtorácico que evidenció disfunción biventricular grave global, con adelgazamiento de las paredes. Las hipótesis diagnósticas fueron compromiso cardíaco por reactivación de enfermedad autoinmu ne versus miocarditis viral. Se realizó una resonancia magnética que confirmó la disfunción ventricular grave en la que se observó realce tardío de gadolinio suges tivo de miocarditis. Se indicó tratamiento con pulsos de metilprednisolona. El primer día de la internación evolucionó con signos de shock cardiogénico y arritmia ventricular refractaria al tratamiento. Posteriormente a una evaluación multidisciplinaria exhaustiva y dificulto sa por el estado clínico, se planteó la posibilidad de un trasplante cardiaco. Se instauró soporte con membrana de oxigenación extracorpórea (ECMO) como puente al trasplante. Al séptimo día de colocado el ECMO, y luego de gran mejoría de los parámetros del hepatograma, recibió un trasplante cardíaco. Tuvo buena evolución postoperatoria, sin embargo, a los dos meses falleció por una infección oportunista. Los resultados de la biopsia del órgano explantado confirmaron el diagnóstico de miocarditis linfocítica.

Abstract Myocarditis is an inflammatory disease of the cardiac tissue of variable etiology, both infectious and non-in fectious. Its presentation can range from asymptomatic to fulminant forms. We present the case of a 24-year-old male patient with a history of autoimmune hepatitis in compensated cirrhotic phase. He consulted for dyspnea of 15 days evolution. He had presented gastrointestinal symptoms one month prior to the consultation. Physical examina tion revealed signs of heart failure. Laboratory examina tion showed elevated cardiac biomarkers and acute on chronic hepatic insufficiency. A transthoracic echocar diogram showed severe global biventricular dysfunction. The diagnostic hypotheses were cardiac involvement due to reactivation of autoimmune disease versus viral myocarditis. An MRI was performed which confirmed very severe ventricular dysfunction and late gadolinium enhancement suggestive of myocarditis. It was indicated treatment with methylprednisolone pulses. On the first day of hospitalization he evolved with clear signs of car diogenic shock and ventricular arrhythmia refractory to medical treatment. After an exhaustive multidisciplinary evaluation, which was difficult due to his clinical condi tion, the possibility of a heart transplant was considered. Extracorporeal membrane oxygenation (ECMO) support was established as a bridge to transplantation. On the seventh day after ECMO, and after great improvement of the hepatogram parameters, the patient received a heart transplant. He had good postoperative evolution. However, he died two months after the transplant due to an opportunistic infection. The results of the biopsy of the explanted organ confirmed the diagnosis of lym phocytic myocarditis.

Miocarditis inducida por Clozapina: Revisión y protocolo de Screening

Clozapina, el gold standard en esquizofrenia refractaria, presenta algunos efectos adversos que ocasionalmente pueden ser graves. Entre ellos, la miocarditis precoz es un efecto cardiovascular severo poco frecuente que puede aparecer en las primeras 4-6 semanas. Las cifras de incidencia oscilan entre el 0,015-0.188% en el mundo, siendo más altas en Australia. La etiología es desconocida, postulándose hipersensibilidad mediada por Ig E; hipereosinofilia y hiperadrenergia. Múltiples investigaciones avalan a la ecocardiografía como una de las técnicas más útiles para el diagnóstico. La biopsia endomiocárdica es definitoria pero no viable. Existen, asimismo, criterios de RNM indicativos de inflamación miocárdica. Para facilitar el diagnóstico, se han propuesto criterios clínicos y analíticos de screening (hemograma, ECG, CK, PCR, troponinas). En caso de sospecha de miocarditis, el cese de clozapina y el tratamiento de soporte es la actitud a seguir, habitualmente con buenos resultados.

Although Clozapine is the gold standard treatment in resistant-schizophrenia, severe or even life-threatening adverse effects must be taked into account. Early myocarditis, a severe but unusual cardiovascular effect, can appear in the first 4-6 weeks of initiation. Incidence rates of myocarditis are about 0,015-0,188% around the world, being more elevated in Australia. Aethiology is unknown, suggesting Ig E mediated hipersensibility, hiperaeosinophilia and hiperadrenergy. Echocardiography seems to be one of the most helpful tools for diagnosing myocarditis. Endomyocardial biopsy is definitive, but not usually available. A role for cardiac magnetic resonance imaging (MRI) also has been proposed (findings of inflammation). In order to make an early diagnosis, several screening-criteria, considering clinical and laboratory ones, have been proposed: aeosinophylia, creatininkinase, C Reactive Proteine, troponin, and EKG. If we suspected clozapine-induced myocarditis, the drug must be removed and support medical treatment must be indicated.

Chlamydia psittaci—related pleuro-myocarditis

ABSTRACT Chlamydia psittaci - related community-acquired pneumonia associated to acute myocarditis was diagnosed in a young man with no medical history, and a professional exposition to birds. The diagnosis was confirmed with positive specific polymerase chain reaction in bronchoalveolar lavage. The patient was treated with spiramycin for two weeks with anti-inflammatory treatment for myocarditis for three months. Clinical and biological improvement was rapidly observed followed by normalization of electrocardiogram and chest CT scan. No relapse was reported for over a two-year follow-up.

Levosimendan: efficacy and safety in pediatric heart failure treatment

SUMMARY OBJECTIVE: The objective of this study was to assess the effectiveness and safety of levosimendan as an alternative treatment for pediatric patients with decompensated heart failure unresponsive to conventional inotropes and to emphasize its role in enhancing cardiovascular stability. METHODS: A total of 15 pediatric patients with decompensated heart failure, stemming from acute fulminant myocarditis (53.3%) and post-congenital heart disease surgery complications (46.7%), received levosimendan. The evaluation focused on adverse effects, respiratory support requirements, and concurrent inotropic medication use during levosimendan treatment. Key cardiovascular parameters were assessed at 0, 6, 12, and 24 h post-levosimendan infusion. RESULTS: Levosimendan administration significantly improved key cardiovascular metrics. Left ventricular ejection fraction increased notably from 45±14.8% to 58±15.6% at 24 h (p<0.001). Systolic and diastolic blood pressures rose significantly, with systolic increasing from 79 (68-90) to 98 (89-109) mmHg and diastolic from 47 (40-57) to 66 (54-76) mmHg by 24 h (p<0.001). Heart rate decreased from 162 (111-175) to 132 (99-148) bpm (p=0.02), and lactate levels significantly decreased from 4.15 (2.3-6.5) to 1.85 (0.8-2.6) mmol/L within 6 h (p<0.001). CONCLUSION: Levosimendan demonstrates its significance in managing pediatric heart failure, indicating its safety and potential to enhance cardiac outcomes by reducing reliance on traditional inotropes.

[Myocardiopericarditis in adult still's disease]. / Miocardiopericarditis en la enfermedad de still del adulto.

Cardiac involvement in Adult-onset Still's Disease (AOSD) usually manifests as a pericardial disease, that has a benign course. The myocarditis is a rare complication with 7% of prevalence. The diagnosis of AOSD is based in the Yamaguchi or Fautrel criteria. The treatment with steroids and methotrexate is the first and second therapeutic lines, respectively, the combination is effective in 70% of cases. We report a case of AOSD with unusual presentation due to myocardial and pericardial commitment.

Comparison of Incidence and Prognosis of Myocardial Injury in Patients with COVID-19-Related Respiratory Failure and Other Pulmonary Infections: A Contemporary Cohort Study.

Myocardial injury (MI) is frequent in critically ill patients with COVID-19, but its pathogenesis remains unclear. We hypothesized that MI is not solely due to viral infection by SARS-CoV-2 but rather due to the common pathophysiological mechanisms associated with severe pulmonary infections and respiratory failure. This contemporary cohort study was designed to compare the incidence of MI in patients with acute respiratory failure caused by COVID-19 to patients with other pulmonary infections. In addition, we aimed to investigate whether MI was a distinct risk factor for in-hospital mortality in patients with COVID-19 compared to those with non-COVID-19 infections. This study included 1444 patients with COVID-19 (55.5% men; age 58 (46;68) years) and 182 patients with other pulmonary infections (46.9% men; age 62 (44;73) years). The incidence of MI at ICU admission was lower in COVID-19 patients (36.4%) compared to non-COVID-19 patients (56%), and this difference persisted after adjusting for age, sex, coronary artery disease, heart failure, SOFA score, lactate, and C-reactive protein (RR 0.84 (95% CI, 0.71-0.99)). MI at ICU admission was associated with a 59% increase in mortality (RR 1.59 (1.36-1.86); p < 0.001), and there was no significant difference in the mortality between patients with COVID-19 and those with other pulmonary infections (p = 0.271). We concluded that MI is less frequent in patients with critical COVID-19 pneumonia and respiratory failure compared to those with other types of pneumonia. The occurrence of MI is a significant risk factor for in-hospital mortality, regardless of the etiology of the pulmonary infection.

Understanding yellow fever-associated myocardial injury: an autopsy study.

BACKGROUND: Yellow fever (YF) is a viral hemorrhagic fever, endemic in parts of South America and Africa. There is scarce evidence about the pathogenesis of the myocardial injury. The objective of this study is to evaluate the cardiac pathology in fatal cases of YF. METHODS: This retrospective autopsy study included cases from the São Paulo (Brazil) epidemic of 2017-2019. We reviewed medical records and performed cardiac tissue histopathological evaluation, electron microscopy, immunohistochemical assays, RT-qPCR for YF virus (YFV)-RNA, and proteomics analysis on inflammatory and endothelial biomarkers. FINDINGS: Seventy-three confirmed YF cases with a median age of 48 (34-60) years were included. We observed myocardial fibrosis in 68 (93.2%) patients; cardiomyocyte hypertrophy in 68 (93.2%); endothelial alterations in 67 (91.8%); fiber necrosis in 50 (68.5%); viral myocarditis in 9 (12.3%); and secondary myocarditis in 5 (6.8%). Four out of five patients with 17DD vaccine-associated viscerotropic disease presented with myocarditis. The cardiac conduction system showed edema, hemorrhages and endothelial fibrinoid necrosis. Immunohistochemistry detected CD68-positive inflammatory interstitial cells and YFV antigens in endothelial and inflammatory cells. YFV-RNA was detected positive in 95.7% of the cardiac samples. The proteomics analysis demonstrated that YF patients had higher levels of multiple inflammatory and endothelial biomarkers in comparison to cardiovascular controls, and higher levels of interferon gamma-induced protein 10 (IP-10) in comparison to sepsis (p = 0.01) and cardiovascular controls (p < 0.001) in Dunn test. INTERPRETATION: Myocardial injury is frequent in severe YF, due to multifactorial mechanisms, including direct YFV-mediated damage, endothelial cell injury, and inflammatory response, with a possible prominent role for IP-10. FUNDING: This study was funded by Fundação de Amparo à Pesquisa do Estado de São Paulo, Bill and Melinda Gates Foundation, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior.