Une double discordance cardiaque complexe décompensée, à propos d'un cas et revue de la littérature / A double cardiac discordance decompensated, about a case and review of the literature

La double discordance est une cardiopathie congénitale complexe extrêmement rare, elle se caractérise par une discordance auriculo-ventriculaire suivie d'une autre discordance ventriculo-artérielle. Son diagnostic est posé généralement à l'âge adulte par des examens d'imagerie. Son pronostic dépend essentiellement des autres malformations congénitales cardiaques associées, des arythmies et des troubles de la conduction, ainsi que de la fonction systolique du ventricule droit en position systémique. Nous rapportons le cas d'un patient âgé de 23 ans, porteur d'une cardiopathie congénitale complexe cyanogène. Il s'agit d'une double discordance associée à une large communication interventriculaire sous aortique avec un shunt inversé et une hypoplasie de l'artère pulmonaire. Ce diagnostic a été confirmé par l'imagerie multimodale. Non opéré, le patient a vu son stade fonctionnel s'aggraver rapidement avec une dyspnée qui est passée d'un stade I à un stade III-IV de la New York Heart Association (NYHA), et apparition de signes hypoxiques et congestifs. A travers cette observation, nous avons précisé les caractéristiques anatomocliniques de cette cardiopathie congénitale complexe cyanogène, son exploration, ses options thérapeutiques, ainsi que le rôle péjoratif de son association avec d'autres malformations congénitales.

Double discordance is an extremely rare complex congenital heart disease; It is characterized by atrioventricular discordance followed by another ventriculo-arterial discordance. Its diagnosis is usually made in adulthood by imaging examinations. Its prognosis depends mainly on other associated congenital heart defects, arrhythmias and disorders of the conduction, as well as systolic function of the right ventricle in the systemic position. We report the case of a 23-year-old patient with a complex cyanogen heart disease.It is a double discordance associated to an interventricular communication with reverse shunt and an hypoplasia of the pulmonary artery.This Diagnosis was confirmed in multimodal imaging. Non-operated, the patient saw his functional status worsen rapidly with dyspnea which went from stage I to stage III-IV of the New York Heart Association (NYHA), and appearance of hypoxic and congestive signs. Through this observation, we have clarified the anatomoclinical characteristics of this complex congenital cyanogens heart disease, the necessary explorations and the different therapeutic options, as well as the pejorative role of its association with other congenital malformations.

Perfil dos usuários de dispositivos cardíacos eletrônicos implantavéis em um hospital universitário / Perfil de usuario de dispositivos cardíacos electrónicos implantables en un hospital universitario / User profile of implantable electronic cardiac devices in a university hospital

Objetivo:Identificar o perfil dos pacientes submetidos à inserção de dispositivos cardíacos eletrônicos implantáveis em um hospital de referência do Rio Grande do Norte.Método:Trata-se de um estudo descritivo, exploratório, retrospectivo dos últimos 03 anoscom abordagem quantitativa. Amostragem foiselecionada por conveniência. A coleta de dados ocorreu entre outubrode 2017 a março de 2018.Resultados: A amostra foi composta por 215prontuários,destes 182 foram analisados.Implantarammarca-passos63,7% e 28% cardiodesfibriladores, corresponderam ao sexo masculino69,3%,com média de idade 65 e 49.Entre as comorbidades,a Hipertensão Arterial Sistêmicaabrangeu 87,4%.Evidenciaram-se os bloqueios atrioventriculares como principal causa para implantes (35%), seguidos das miocardiopatias (12%).Conclusão:Percebeu-se que, os indivíduos que implantaram marcapassos eram acometidos por bradiarritmias,enquanto cardiodesfibriladores por taquiarritmias. As complicações pós-operatórias e intercorrências durante o procedimento foram de baixo risco. Salienta-se, que no manejo desses usuários é fundamental a elaboração de um protocolo, visando aperfeiçoar o cuidado.(AU)

Objective: Toidentifytheprofileofpatientsundergoinginsertionof implantable electroniccardiacdevices in a reference hospital in Rio Grande do Norte. Method: Thisis a descriptive, exploratory,retrospective studyofthelastthreeyearswith a quantitativeapproach. Samplingwasselectedby convenience. Data collectionoccurredbetweenOctober 2017 to March 2018. Results: Samplecomposedof 215 medical records, ofthese 182 wereanalyzed. Implantedpacemakers 63.7% and 28% cardiodesfibrillators, corresponded tothe male gender 69.3%, withaverageage 65 and 49. Amongthecomorbidities, Systemic Arterial Hypertensioncovered 87.4%. Theatrioventricular blocks wereevidenced as themain cause forimplantation (35%), followedbymyocardiopathies (12%). Conclusion: Itwasnoticedthatindividualswhoimplantedpacemakerswereaffectedbybradyarrhythmias, whilecardioverter-defibrillatorswereaffe ctedbytachyarrhythmias. Thepostoperativecomplications and complicationsduringtheprocedurewerelowrisk. Itisemphasizedthat in themanagementoftheseusersitisessentialtodevelop a protocol, aimingtoimprove care.(AU)

Objetivo: identificar el perfil de los pacientes sometidos a la inserción de dispositivos cardíacos electrónicos implantables en el hospital de referencia de Rio Grande do Norte. Método: se trata de un estudio descriptivo, exploratorio, retrospectivo de los últimos 3 años con enfoque cuantitativo. El muestreo fue seleccionado por conveniencia. La recolección de datos se llevó a cabo entre octubre de 2017 y marzo de 2018. Resultados: muestra compuesta por 215 historias clínicas, de las cuales se analizaron 182. Marcapasos implantados 63,7% y desfibriladores cardioversores 28%, correspondieron al sexo masculino 69,3%, con una edad media de 65 y 49 años. Entre las comorbilidades, la Hipertensión Arterial Sistémica cubrió el 87,4%. Los bloqueos auriculoventriculares se evidenciaron como la principal causa de implantes (35%), seguida de las miocardiopatías (12%). Conclusión: se notó que, los portadores de marcapasos se vieron afectados por bradiarritmias, mientras que los desfibriladores cardioversores por taquiarritmias. Las complicaciones postoperatorias y las complicaciones durante el procedimiento fueron de bajo riesgo. Cabe señalar que en el manejo de estos usuarios es fundamental la elaboración de un protocolo, con el fin de mejorar la atención.(AU)

Intervenções de enfermagem no cuidado aos pacientes portadores de arritmias cardíacas / Intervenciones de enfermería en el cuidado de pacientes con arritmia cardíaca / Nursing interventions in the care of patients with heart arrhythmia

Objetivo: as arritmias cardíacas acometem mais de 20 milhões de brasileiros, desse modo, o presente estudo objetiva realizar um levantamento sobre as intervenções de enfermagem diante de um quadro de arritmia em ambiente hospitalar. Método: trata-se de revisão integrativa de literatura de caráter descritivo, realizada entre janeiro e fevereiro de 2022. Por meio de buscas na biblioteca virtual de saúde BVS (Lilacs, Medline, BDEnf, IBECs, PAHO) e Scielo BDenf de artigos publicados nos últimos 5 anos. Resultados: os enfermeiros têm aptidão para identificar anormalidades no ritmo cardíaco. A compreensão das complicações pós-operatórias contribui para a elaboração de um plano de cuidado mais eficaz. As intervenções de enfermagem devem ser pautadas no monitoramento da arritmia, bem como orientação sobre o uso dos antiarrítmicos e esclarecimento de dúvidas sobre a doença. Conclusão: é imprescindível a atuação do enfermeiro na assistência a pacientes com arritmias cardíacas, o qual necessitam monitorar os sinais vitais para determinar o efeito hemodinâmico de tal problema cardíaco, manter uma atitude tranquilizadora e compartilhar informações sobre a patologia e seu tratamento.(AU)

Objective: cardiac arrhythmias affect more than 20 million Brazilians, thus, the present study aims to carry out a survey on nursing interventions in the face of arrhythmia in a hospital environment. Method: Method: this is an integrative literature review of a descriptive nature, carried out between January and February 2022. Through searches in the virtual health library VHL (Lilacs, Medline, BDEnf, IBECs, PAHO) and Scielo. Results: nurses are able to identify heart rhythm abnormalities. Understanding postoperative complications contributes to the development of a more effective care plan. Nursing interventions should be guided by the monitoring of arrhythmia, as well as guidance on the use of antiarrhythmics and clarification of doubts about the disease. Conclusion: it is essential for nurses to assist patients with cardiac arrhythmias, who need to monitor vital signs to determine the hemodynamic effect of such a heart problem, maintain a reassuring attitude and share information about the pathology and its treatment.(AU)

Objetivo: las arritmias cardíacas afectan a más de 20 millones de brasileños, por lo tanto, el presente estudio tiene como objetivo realizar una encuesta sobre las intervenciones de enfermería frente a la arritmia en un ambiente hospitalario. Método: se trata de una revisión integrativa de la literatura de carácter descriptivo, realizada entre enero y febrero de 2022. Mediante búsquedas en la biblioteca virtual en salud BVS (Lilacs, Medline, BDEnf, IBECs, PAHO) y Scielo. Resultados: los enfermeros logran identificar alteraciones del ritmo cardíaco. Comprender las complicaciones posoperatorias contribuye al desarrollo de un plan de atención más eficaz. Las intervenciones de enfermería deben estar guiadas por el seguimiento de la arritmia, así como orientación sobre el uso de antiarrítmicos y aclaración de dudas sobre la enfermedad. Conclusión: es fundamental que los enfermeros ayuden a los pacientes con arritmias cardíacas, que necesitan monitorear los signos vitales para determinar el efecto hemodinámico de tal problema cardíaco, mantener una actitud tranquilizadora y compartir información sobre la patología y su tratamiento.(AU)

The Role of the Immune System on the Cardiac Complications Observed in SARS-CoV-2

Abstract An acute respiratory syndrome caused by SARS-CoV2 was declared a pandemic by the World Health Organization. Current data in the world and in Brazil show that approximately 40% of patients who died have some type of cardiac comorbidity. There are also robust reports showing an increase in IL-6 / IL-1B / TNF-alpha and the presence of lymphopenia in patients with COVID-19. Our team and others have shown that increased cytokines are the link between arrhythmias/Left ventricular dysfunction and the immune system in different diseases. In addition, it has been well demonstrated that lymphopenia can not only be a good marker, but also a factor that causes heart failure. Thus, the present review focused on the role of the immune system upon the cardiac alterations observed in the SARS-CoV2 infection. Additionally, it was well described that SARS-CoV-2 is able to infect cardiac cells. Therefore, here it will be reviewed in deep.

Autonomic dysfunction is common in liver cirrhosis and is associated with cardiac dysfunction and mortality: prospective observational study

ABSTRACT BACKGROUND: Although autonomic dysfunction has been shown to be associated with liver cirrhosis, the prevalence and prognostic implications are unclear. Abnormal heart rate variability (HRV), a measure of autonomic function, has not been well investigated in cirrhosis. OBJECTIVE: To evaluate the prevalence of high-risk HRV parameters in a cohort of cirrhotic patients and their association with cardiac dysfunction and mortality. DESIGN AND SETTING: Prospective observational study conducted in the Federal University of São Paulo. METHOD: A cohort of 120 patients, comprising 17 healthy controls and 103 cirrhotic outpatients, was evaluated and followed for 10 months. HRV analysis was based on 24-hour Holter monitoring and defined using time-domain and frequency-domain parameters. RESULTS: The HRV parameters were statistically lower in cirrhotic patients than in healthy subjects. High-risk HRV parameters were prevalent, such that 64% had at least one high-risk parameter. Time-domain parameters correlated with Child scores (P < 0.0001). In regression models, HRV parameters were independent predictors of diastolic dysfunction and mortality. During 10 months of follow-up, there were 11 deaths, all of patients with at least one high-risk HRV parameter. Kaplan-Meier analysis estimated low survival rates among patients with standard deviation of normal-to-normal RR intervals (SDNN) < 100. CONCLUSION: Reduced HRV is prevalent in liver cirrhosis and is related to cardiac dysfunction, severity of liver disease and mortality. Abnormal high-risk HRV parameters are prevalent among cirrhotic patients and are also predictors of mortality. Our findings highlight the need for a more careful cardiac evaluation of cirrhotic patients.

Predictive Value of Myocardial injury in Patients with COVID-19 Admitted to a Quaternary Hospital in the City of Rio de Janeiro

Abstract Background In Brazil the factors involved in the risk of death in patients with COVID-19 have not been well established. Objective To analyze whether elevations of high-sensitivity troponin I (hTnI) levels influence the mortality of patients with COVID-19. Methods Clinical and laboratory characteristics of hospitalized patients with COVID-19 were collected upon hospital admission. Univariate and binary logistic regression analyzes were performed to assess the factors that influence mortality. P-value<0.05 was considered significant. Results This study analyzed192 patients who received hospital admission between March 16 and June 2, 2020 and who were discharged or died by July 2, 2020. The mean age was 70±15 years, 80 (41.7%) of whom were women. In comparison to those who were discharged, the 54 (28.1%) who died were older (79±12 vs 66±15years; P=0.004), and with a higher Charlson´s index (5±2 vs 3±2; P=0.027). More patients, aged≥60years (P <0.0001), Charlson´s index>1 (P=0.004), lung injury>50% in chest computed tomography (P=0.011), with previous coronary artery disease (P=0.037), hypertension (P=0.033), stroke (P=0.008), heart failure (P=0.002), lymphocytopenia (P=0.024), high D-dimer (P=0.024), high INR (P=0.003), hTnI (P<0.0001), high creatinine (P<0.0001), invasive mechanical ventilation (P<0.0001), renal replacement therapy (P<0.0001), vasoactive amine (P<0.0001), and transfer to the ICU (P=0.001), died when compared to those who were discharged. In logistic regression analysis, elevated hTnI levels (OR=9.504; 95% CI=1.281-70.528; P=0.028) upon admission, and the need for mechanical ventilation during hospitalization (OR=46.691; 95% CI=2.360-923.706; P=0.012) increased the chance of in-hospital mortality. Conclusion This study suggests that in COVID-19 disease, myocardial injury upon hospital admission is a harbinger of poor prognosis.

Disjunção do anel mitral: modalidades diagnósticas, implicações clínicas e evolução prognóstica / Mitral annulus disjunction: diagnostic modalities, clinical implications, and prognostic progression

A disjunção do anel mitral (DAM) é uma inserção anormal da linha de flexão do anel mitral na parede atrial. O anel mostra uma separação (disjunção) entre a junção folheto posterior-parede atrial e a crista miocárdica ventricular esquerda.1 A DAM foi descrita pela primeira vez há mais de 30 anos em estudo de autópsia, estando relacionada com prolapso da valva mitral (PVM) em 92% dos casos.2 Desde então, foram realizados diversos estudos, sendo a prevalência de DAM em pacientes com PVM reportada de forma variável, podendo ou não estar associada à insuficiência mitral. O ecocardiograma transtorácico (ETT) faz parte da avaliação inicial do prolapso valvar mitral, permitindo o diagnóstico e a avaliação de complicações relacionadas. Com a evolução de novos métodos diagnósticos, a ressonância magnética cardíaca (RMC) e o ecocardiograma transesofágico (ETE) passaram a aprimorar a avaliação dessa patologia, bem como de sua extensão e localização. Contudo, as características fenotípicas do PVM que estão mais associadas a DAM permanecem incertas, sobretudo devido ao número limitado de pacientes, nos estudos clássicos sobre o tema. Portadores de DAM podem desenvolver sintomas relacionados a arritmias ventriculares, configurando a síndrome arrítmica da DAM (SDAM), podendo evoluir para morte súbita. Na literatura, os dados prognósticos ainda são conflitantes entre os diversos estudos acerca do tema, indo desde critérios claros de diagnóstico, o melhor método de imagem a ser aplicado, o tratamento e o prognóstico. Esta revisão descreve as características da DAM associada ou não ao prolapso valvar, auxiliando no diagnóstico e na conduta dessa importante patologia. (AU)

Mitral annulus disjunction (MAD) is an abnormal insertion of the flexion line of the mitral annulus into the atrial wall. The annulus presents a separation (disjunction) between the posterior leaflet­atrial wall junction and the left ventricular myocardial crest.1 MAD was first described more than 30 years ago in an autopsy study and is reportedly related to mitral valve prolapse (MVP) in 92% of cases.2 Since then, several studies have been conducted, and reports on the prevalence of MAD in patients with MVP have varied. Ultimately, it may or may not be associated with mitral regurgitation. Transthoracic echocardiography is part of initial MVP assessment, allowing its diagnosis and the assessment of related complications. As new diagnostic methods emerged, cardiac magnetic resonance imaging and transesophageal echocardiography improved the assessment of this pathology in terms of its diagnosis, extension, and location. However, the phenotypic characteristics of MVP that are more closely associated with MAD remain uncertain mainly due to the limited number of patients in classic studies on the subject. Patients with MAD may develop symptoms related to ventricular arrhythmias, configuring the MAD arrhythmic syndrome, which may progress to sudden death. The literature presents conflicting prognostic data among several studies on the subject from clear diagnostic criteria and best imaging method to be used to treatment and prognosis. This review describes MAD characteristics associated (or not) with valve prolapse to improve the diagnosis and management of this important pathology. (AU)

Acometimento miocárdico na Doença de Chagas: uma perspectiva a partir da avaliação pela ressonância magnética cardiovascular / Myocardial involvement in Chagas Disease: from the perspective of cardiovascular magnetic ressonance assessment

A doença de Chagas representa um importante problema de saúde pública, sobretudo nos países endêmicos da América Latina. Dentre suas apresentações clínicas, a cardiomiopatia crônica é a mais frequente. De patogênese multifatorial, o acometimento miocárdico pode levar à insuficiência cardíaca, a eventos tromboembólicos, a arritmias e à morte súbita. Nesse contexto, a ressonância magnética cardiovascular é um excelente método não invasivo para a investigação do dano miocárdico e a compreensão dos mecanismos e consequências relacionados às essas lesões. Com elevada resolução espacial e capacidade de caracterização tecidual, a ressonância magnética cardiovascular proporciona análise morfofuncional altamente confiável e possibilita a identificação de marcadores de risco de eventos adversos em pacientes com doença de Chagas, sendo de grande utilidade para o diagnóstico e o acompanhamento desses indivíduos na rotina clínica. (AU)

Chagas disease represents an important public health problem, especially in endemic countries in Latin America. Chronic cardiomyopathy is its most frequent clinical presentation. Myocardial involvement has a multifactorial pathogenesis and can lead to heart failure, thromboembolic events, arrhythmias, and sudden death. In this context, cardiovascular magnetic resonance imaging (CMR) is an excellent noninvasive method for investigating myocardial damage and understanding the mechanisms and consequences of these injuries. CMR has high spatial resolution and tissue characterization capacity, enabling a highly reliable morphofunctional analysis and the identification of risk markers for adverse events in patients with Chagas disease. This exam is very useful for the diagnosis and follow-up of these patients in the routine clinical setting. (AU)

Comparison on the clinical characteristics of patients with Takotsubo syndrome from China and from Europe/North America / 中华心血管病杂志

Objective: To summarize the clinical characteristics of patients with Takotsubo syndrome (TTS) from China and compare these features with patients from Europe/North America. Methods: We reviewed case reports published between 1990 and 2020 with the key words of "Takotsubo syndrome" "stress cardiomyopathy" "apical balloon syndrome" and "broken heart syndrome", in Wanfang, CNKI, Pubmed and Web of Science databases, and 1 294 articles were identified, including 128 articles reporting 163 cases in China and 1 166 articles reporting 1 256 cases in Europe/North America. The characteristics of demographics, triggers, symptoms, electrocardiogram, echocardiography, left ventriculogram,coronary angiography, treatment and prognosis were analyzed and compared between Chinese and European/North American cases. Results: A total of 1 294 articles (1 419 cases: 163 from China, 1 256 from Europe/North America) were included in the final analysis. The characteristics of Chinese cases included: (1) demographic:the age was (59.6±16.9) years, which was similar with that of European/North American ((59.7±17.4) years, P=0.90), and female accounting for 78.5% (128/163), which was lower than that of European/North American (85.4% (1 073/1 256), P=0.02). (2) Triggers:mental triggers accounted for 48.5% (79/163), physical triggers accounted for 43.6% (71/163), and no triggers accounted for 7.9% (13/163), respectively. Compared with Europe/North America, the ratio of patients with mental triggers was higher in China, while the ratio of patients with physical triggers and no triggers was lower (P<0.05). (3) Symptoms: chest pain (52.8% (86/163)), chest tightness (35.0% (57/163)), shortness of breath (33.1% (54/163)), dizziness (16.0% (26/163)), sweating (15.3% (25/163)), palpitations (12.3% (20/163)), syncope (9.2% (15/163)) abdominal pain/diarrhea (8.6% (14/163)), hypotension (7.4% (12/163)), and fatigue (1.2% (2/163)) were illustrated in sequence. Compared with patients in Europe/North America, the ratio of patients with chest tightness, dizziness, sweating, palpitations, abdominal pain/diarrhea was higher in Chinese patients, while the ratio of patients with hypotension was lower in Chinese patients (P<0.05). (4) Electrocardiogram: main manifestations were myocardial ischemia symptoms, such as ST-segment elevation (63.8% (104/163)), T wave inversion (46.0% (75/163)), ST-segment depression (8.6% (14/163)). Compared with European/North American, the ratio of patients with ST-segment elevation, T wave inversion, and atrioventricular block was higher in Chinese patients (P<0.05). (5) Echocardiography and imaging:apical dyskinesia (59.5% (97/163)) and apical/left ventricular bulbar dilation (36.2%(59/163)) dominated the echocardiography findings. Compared with European/North American, the ratio of patients with apical dyskinesia, apical/left ventricular bulbar dilation, and mitral regurgitation was higher in Chinese patients, while the ratio of patients with dyskinesia in other parts and left ventricular ejection fraction<50% was lower in Chinese patients (P<0.05). Left ventricular angiography showed 36.2% (59/163) of apical dyskinesia in Chinese patients, which was higher than that reported in European/North American patients, and 38.7% (63/163) of apical/left ventricular bulbar dilation was reported in Chinese patients, which was similar to that reported in European/North American patients. Coronary angiography showed percent of no stenosis or stenosis less than 50% was 87.1% (142/163), which was similar to that reported in European/North American patients (P>0.05). The typical type of TTS accounted for 96.3% (157/163), which was significantly higher than that reported in European/ American patients, while the ratio of basal type and midventricular type was lower (P<0.01). (6) Treatment and prognosis:the applied drugs in China were listed in order as following, β-blockers (41.1% (67/163)), antiplatelet agents (37.4%(61/163)), ACEI/ARB (36.2%(59/163)), anticoagulants (27.0%(44/163)), diuretics (19.6% (32/163)), etc. Compared with Europe/North America, the ratio of antiplatelet agents, anticoagulants, statins, diuretics, and nitrates use was higher in China (P<0.05), while the use of oxygen therapy and IABP was similar (P>0.05). The hospital mortality in China was 5.5% (9/163), during 1-year follow-up the recurrence rate was 3.7% (6/163) and the mortality was 0. The prognosis was similar with that in Europe/North America. Conclusions: Compared with TTS cases in Europe/North America, TTS cases in China also occur usually in middle-aged and elderly women, most of whom have mental/physical triggers and typical imaging manifestations, followed by a low hospital mortality rate and recurrence rate.

Application of wearable 12-lead electrocardiogram devices in pre-hospital diagnosis of acute ST segment elevation myocardial infarction / 南方医科大学学报

OBJECTIVE@#To assess the value of wearable 12-lead electrocardiogram (ECG) devices in pre-hospital diagnosis of acute ST segment elevation myocardial infarction (STEMI).@*METHODS@#This analysis was conducted among 441 patients selected from the''National ECG Network'', who used wearable 12-lead ECG device with critical situation warning of ST change between January 2019, and August, 2021.The general characteristics, response time and complaints of the patients with STEMI were analyzed.The accuracy of pre-hospital diagnosis of STEMI was compared between clinician's interpretation of ECGs and AI diagnosis by the wearable ECG device.@*RESULTS@#In 89 of the patients, a pre-hospital diagnosis of STEMI was made by physicians based on ECGs from the wearable devices, and 58 of them sought medical attention after online warning, with a referral rate of 65.17%.The average time for diagnostic assessment of the ECGs was 153.02 s, and the average time for confirmation of the diagnosis was 178.06 s.The sensitivity for pre-hospital diagnosis of STEMI by clinician's interpretation of the ECGs and by AI diagnosis was 100% and 88.37%, respectively, with a specificity of 95.40% and 79.31%, respectively.The pre-hospital diagnosis by clinicians and AI diagnosis of STEMI both showed a high consistency with the subsequent definite clinical diagnosis of STEMI.@*CONCLUSION@#Wearable 12-lead ECG devices can accurately record ECG characteristics of STEMI patients outside the hospital and allow immediate data uploading for an early diagnosis.The diagnoses of STEMI made based on AI technology are highly consistent with those by clinicians, demonstrating excellent clinical performance of the wearable ECG devices.

Impact of late sodium current inhibition on cardiac electrophysiology parameters and ventricular arrhythmias in isolated Langendorff perfused rabbit hearts with short QT interval / 中华心血管病杂志

Objective: To determine the electrophysiological effects and related mechanisms of late sodium current inhibitors on hearts with short QT intervals. Methods: The electrophysiological study was performed on isolated Langendorff perfused rabbit hearts. A total of 80 New Zealand White rabbits were used and 34 hearts without drug treatment were defined as control group A, these hearts were then treated with IKATP opener pinacidil, defined as pinacidil group A. Then, 27 hearts from pinacidil group A were selected to receive combined perfusion with sodium channel inhibitors or quinidine, a traditional drug used to treat short QT syndrome, including ranolazine combined group (n=9), mexiletine combined group (n=9), and quinidine combined group (n=9). Nineteen out of the remaining 46 New Zealand rabbits were selected as control group B (no drug treatments, n=19), and then treated with pinacidil, defined as pinacidil group B (n=19). The remaining 27 rabbits were treated with sodium inhibitors or quinidine alone, including ranolazine alone group (n=9), mexiletine alone group (n=9), and quinidine alone group (n=9). Electrocardiogram (ECG) physiological parameters of control group A and pinacidil group A were collected. In control group B and pinacidil group B, programmed electrical stimulation was used to induce ventricular arrhythmias and ECG was collected. ECG physiological parameters and ventricular arrhythmia status of various groups were analyzed. The concentrations of pinacidil, ranolazine, mexiletine and quinidine used in this study were 30, 10, 30 and 1 μmol/L, respectively. Results: Compared with control group A, the QT interval, 90% of the repolarization in epicardial and endocardial monophasic action potential duration (MAPD90-Epi, MAPD90-Endo) was shortened, the transmural dispersion of repolarization (TDR) was increased, and the effective refractor period (ERP) and post-repolarization refractoriness (PRR) were reduced in pinacidil group A (all P<0.05). Compared with the pinacidil group A, MAPD90-Epi, MAPD90-Endo, QT interval changes were reversed in quinidine combined group and mexiletine combined group (all P<0.05), but not in ranolazine combined group. All these three drugs reversed the pinacidil-induced increases of TDR and the decreases of ERP and PRR. The induced ventricular arrhythmia rate was 0 in control group B, and increased to 10/19 (χ2=13.6, P<0.05) in pinacidil group B during programmed electrical stimulation. Compared with the pinacidil group B, incidences of ventricular arrhythmia decreased to 11% (1/9), 11% (1/9) and 0 (0/9) (χ2=4.5, 4.5, 7.4, P<0.05) respectively in ranolazine group, mexiletine group and quinidine group. Conclusions: Inhibition of late sodium current does not increase but even decreases the risk of malignant arrhythmia in hearts with a shortened QT interval. The antiarrhythmic mechanism might be associated with the reversal of the increase of TDR and the decrease of refractoriness (including both ERP and PRR) of hearts with shortened QT interval.

Cardiovascular events and risk factors in hematological neoplasms patients treated with anthracyclines / 中华心血管病杂志

Objective: To explore the incidence and risk factors of cardiovascular events in hematological neoplasms patients treated with anthracyclines in the real world. Methods: A total of 408 patients with lymphoma and leukemia, who were treated with anthracyclines during hospitalization in the First Affiliated Hospital of Dalian Medical University from January 1, 2018 to July 31, 2021, were included in this retrospective study. Patients were divided into cardiovascular event group (n=74) and non-cardiovascular event group (n=334). The primary endpoint was cardiovascular events (arrhythmia, heart failure, acute myocardial infarction etc.) after anthracyclines therapy. The secondary endpoint was all-cause mortality, cardiovascular-cause death, discontinued chemotherapy due to cardiovascular events. Multivariate regression analysis was used to investigate the risk factors of cardiovascular events. Kaplan-Meier was performed to calculate the incidence of all-cause mortality. Results: The mean age was (55.6±14.9) years, and there were 227 male patients (55.6%) in this cohort. The median follow-up time was 45 months. During follow-up, cardiovascular adverse events occurred in 74 patients (18.1%), including 45 heart failure (38 were heart failure with preserved ejection fraction), 30 arrhythmia, 4 acute myocardial infarction and 2 myocarditis/pericarditis. Multivariate regression analysis showed age (OR=1.024, 95%CI 1.003-1.045, P=0.027) and history of hypertension over 10 years (OR=2.328, 95%CI 1.055-5.134, P=0.036) were independent risk factors for the cardiovascular events. Kaplan-Meier survival curve showed mortality was significantly higher in cardiovascular event group than in non-cardiovascular event group (47.3% vs. 26.6%, P=0.001). In the cardiovascular event group, chemotherapy was discontinued in 9 cases (12.2%) due to cardiovascular events and cardiovascular death occurred in 7 cases (9.5%). Conclusions: Although heart failure is the main cardiovascular event in lymphoma and leukemia patients post anthracyclines therapy, other cardiovascular events especially arrhythmias are also common. The presence of cardiovascular events is associated with higher risk of all-cause mortality in these patients. Age and long-term hypertension are independent risk factors for cardiovascular events in lymphoma and leukemia patients after anthracyclines treatment.

Electrocardiogram data recognition algorithm based on variable scale fusion network model / 生物医学工程学杂志

The judgment of the type of arrhythmia is the key to the prevention and diagnosis of early cardiovascular disease. Therefore, electrocardiogram (ECG) analysis has been widely used as an important basis for doctors to diagnose. However, due to the large differences in ECG signal morphology among different patients and the unbalanced distribution of categories, the existing automatic detection algorithms for arrhythmias have certain difficulties in the identification process. This paper designs a variable scale fusion network model for automatic recognition of heart rhythm types. In this study, a variable-scale fusion network model was proposed for automatic identification of heart rhythm types. The improved ECG generation network (EGAN) module was used to solve the imbalance of ECG data, and the ECG signal was reproduced in two dimensions in the form of gray recurrence plot (GRP) and spectrogram. Combined with the branching structure of the model, the automatic classification of variable-length heart beats was realized. The results of the study were verified by the Massachusetts institute of technology and Beth Israel hospital (MIT-BIH) arrhythmia database, which distinguished eight heart rhythm types. The average accuracy rate reached 99.36%, and the sensitivity and specificity were 96.11% and 99.84%, respectively. In conclusion, it is expected that this method can be used for clinical auxiliary diagnosis and smart wearable devices in the future.

Research Progress in Circadian Rhythm and Arrhythmia / 中国医学科学院学报

Studies have demonstrated that the occurrence of a variety of arrhythmias presents an obvious circadian rhythm,which may be regulated by circadian rhythm genes.Circadian cycle and light stimulation can affect circadian rhythm genes and proteins,which constitute a transcription-translation loop that can regulate the ion channels in myocardial cell membrane through nervous-humoral regulation and changes in central clock-sub-clock gene expression,thereby modulating arrhythmia.This article reviews the molecular basis,mechanism,and performance of circadian rhythm in regulating arrhythmia.

Electrocardiogram signal classification algorithm of nested long short-term memory network based on focal loss function / 生物医学工程学杂志

Electrocardiogram (ECG) can visually reflect the physiological electrical activity of human heart, which is important in the field of arrhythmia detection and classification. To address the negative effect of label imbalance in ECG data on arrhythmia classification, this paper proposes a nested long short-term memory network (NLSTM) model for unbalanced ECG signal classification. The NLSTM is built to learn and memorize the temporal characteristics in complex signals, and the focal loss function is used to reduce the weights of easily identifiable samples. Then the residual attention mechanism is used to modify the assigned weights according to the importance of sample characteristic to solve the sample imbalance problem. Then the synthetic minority over-sampling technique is used to perform a simple manual oversampling process on the Massachusetts institute of technology and Beth Israel hospital arrhythmia (MIT-BIH-AR) database to further increase the classification accuracy of the model. Finally, the MIT-BIH arrhythmia database is applied to experimentally verify the above algorithms. The experimental results show that the proposed method can effectively solve the issues of imbalanced samples and unremarkable features in ECG signals, and the overall accuracy of the model reaches 98.34%. It also significantly improves the recognition and classification of minority samples and has provided a new feasible method for ECG-assisted diagnosis, which has practical application significance.

ST segment morphological classification based on support vector machine multi feature fusion / 生物医学工程学杂志

ST segment morphology is closely related to cardiovascular disease. It is used not only for characterizing different diseases, but also for predicting the severity of the disease. However, the short duration, low energy, variable morphology and interference from various noises make ST segment morphology classification a difficult task. In this paper, we address the problems of single feature extraction and low classification accuracy of ST segment morphology classification, and use the gradient of ST surface to improve the accuracy of ST segment morphology multi-classification. In this paper, we identify five ST segment morphologies: normal, upward-sloping elevation, arch-back elevation, horizontal depression, and arch-back depression. Firstly, we select an ST segment candidate segment according to the QRS wave group location and medical statistical law. Secondly, we extract ST segment area, mean value, difference with reference baseline, slope, and mean squared error features. In addition, the ST segment is converted into a surface, the gradient features of the ST surface are extracted, and the morphological features are formed into a feature vector. Finally, the support vector machine is used to classify the ST segment, and then the ST segment morphology is multi-classified. The MIT-Beth Israel Hospital Database (MITDB) and the European ST-T database (EDB) were used as data sources to validate the algorithm in this paper, and the results showed that the algorithm in this paper achieved an average recognition rate of 97.79% and 95.60%, respectively, in the process of ST segment recognition. Based on the results of this paper, it is expected that this method can be introduced in the clinical setting in the future to provide morphological guidance for the diagnosis of cardiovascular diseases in the clinic and improve the diagnostic efficiency.