¿Qué hay de nuevo en el diagnóstico de amiloidosis? / What is new in diagnosis of amyloidosis?

La amiloidosis siempre ha representado un desafío diagnóstico. En el año 2020, el Grupo de Estudio de Amiloidosis (GEA), confeccionó la Guía de Práctica Clínica para el Diagnóstico de Amiloidosis. Nuevas líneas de investigación se han desarrollado posteriormente. Esta revisión narrativa tiene como intención explorar el estado del arte en el diagnóstico de la amiloidosis. En pacientes con amiloidosis se recomienda la tipificación de la proteína mediante espectrometría de masa, técnica de difícil ejecución por requerir de microdisectores láser para la preparación de la muestra. Algunas publicaciones recientes proponen otros métodos para obtener la muestra de amiloide que se va a analizar, permitiendo prescindir de la microdisección. Por otra parte, en pacientes con Amiloidosis ATTR confirmada, la recomendación de secuenciar el gen amiloidogénico se encontraba destinada a los casos sospechosos de ATTR hereditaria (ATTRv,), pero actualmente esta se ha extendido a todos los pacientes sin importar la edad. En lo que respecta a los estudios complementarios orientados al diagnóstico de compromiso cardíaco, se ha propuesto el uso de la inteligencia artificial para su interpretación, permitiendo la detección temprana de la enfermedad y el correcto diagnóstico diferencial. Para el diagnóstico de neuropatía, las últimas publicaciones proponen el uso de la cadena ligera de neurofilamento sérica, que también podría resultar un indicador útil para seguimiento. Finalmente, con referencia a la amiloidosis AL, la comunidad científica se encuentra interesada en definir qué características determinan el carácter amiloidogénico de las cadenas livianas. La N-glicosilación de dichas proteínas impresiona ser uno de los determinantes en cuestión. (AU)

Amyloidosis has always represented a diagnostic challenge. In 2020, the Amyloidosis Study Group (ASG) developed the "Clinical Practice Guideline for the Diagnosis of Amyloidosis". New lines of research have subsequently emerged. This narrative review aims to explore the state of the art in the diagnosis of amyloidosis diagnosis. In patients with amyloidosis, protein typing by mass spectrometry is recommended, a technique hard to perform because it requires laser microdissection for sample preparation. Recent publications propose other methods to obtain the amyloid sample to be analyzed, making it possible to dispense with microdissection. On the other hand, in patients with confirmed TTR amyloidosis (aTTR), the recommendation to sequence the amyloidogenic gene was intended for suspected cases of hereditary aTTR but has now been extended to all patients regardless of age. (AU)

Elaboração de algoritmo para interpretação rápidadas principais arritmias cardíacas no eletrocardiograma / Algorithm Elaboration For Quick Interpretation Of The Main Heart Arrythmias In The Electrocardiogram

Objetivo: relatar a elaboração de um algoritmo para facilitar a interpretação rápida das principais arritmias cardíacas no eletrocardiograma. Método: estudo descritivo, exploratório, com abordagem qualitativa, do tipo relato de experiência, realizado mediante um projeto de intervenção em educação em saúde durante o ano de 2021. Resultados: a elaboração do algoritmo denominado Scaritmo contribuiu para sistematizar as etapas de identificação de arritmias cardíacas, favorecendo o processo didático e aprendizado dos estudantes e otimizando a interpretação rápida do eletrocardiograma. Conclusão: o uso do algoritmo Scaritmo permite a sistematização teórico-prática das etapas necessárias para a interpretação do eletrocardiograma tornando sua avaliação mais didática e assertiva pelo examinador em treinamento.(AU)

Objective: to report the development of an algorithm to facilitate the rapid interpretation of the main cardiac arrhythmias in electrocardiogram. Method: a descriptive, exploratory study with qualitative approach, of experience report type, conducted through an intervention project in health education during the year 2021. Results: The development of the algorithm called Scaritmo contributed to systematize the steps of cardiac arrhythmia identification, favoring the didactic process and student learning, and optimizing the rapid interpretation of the electrocardiogram. Conclusion: The use of the Scaritm algorithm allows the theoretical and practical systematization of the steps necessary for the interpretation of electrocardiograms, making its evaluation more didactic and assertive by the examiner in training.(AU)

Objetivo: relatar el desarrollo de un algoritmo para facilitar la interpretación rápida de las principales arritmias cardíacas en electrocardiograma. Método: estudio descriptivo, exploratorio, con abordaje cualitativo, de tipo relato de experiencia, realizado a través de un proyecto de intervención en educación para la salud durante el año 2021. Resultados: el desarrollo del algoritmo denominado Scaritmo contribuyó para sistematizar los pasos de identificación de arritmias cardíacas, favoreciendo el proceso didáctico y el aprendizaje de los alumnos y optimizando la rápida interpretación del electrocardiograma. Conclusión: El uso del algoritmo Scaritmo permite la sistematización teórica y práctica de los pasos necesarios para la interpretación del electrocardiograma, tornando su evaluación más didáctica y asertiva por el examinador en formación.(AU)

Como eu faço no Coração de Atleta: avaliação dos diferentes tipos de adaptação ao exercício / My approach to "Athlete'S Heart": evaluation of the different types of adaptation to exercise

A prática regular de esportes pode induzir adaptações no coração, sendo essa condição comumente chamada de "coração de atleta". As alterações observadas incluem dilatação das câmaras cardíacas, aumento da espessura miocárdica, melhora do enchimento ventricular, aumento da trabeculação do ventrículo esquerdo (VE), dilatação da veia cava inferior, entre outras. Essas alterações também podem ser observadas em algumas doenças cardíacas, como cardiomiopatia (CMP) dilatada, hipertrófica e outras. Dessa forma, os exames de imagem cardíaca são fundamentais na identificação dessas alterações e na diferenciação entre o "coração de atleta" e uma possível cardiopatia.(AU)

Exercise-induced adaptation may occur in amateur and professional athletes. This condition is commonly named "athlete's heart". The alterations observed include dilation of the heart chambers, increased myocardial thickness, improved ventricular filling, increased left ventricular trabeculation, dilation of the inferior vena cava, among others. These changes can also be observed in some heart diseases, such as dilated, hypertrophic and other cardiomyopathies (CMP). Thus, cardiac imaging tests are fundamental in identifying these alterations and in differentiating between "athlete's heart" and possible heart disease. (AU)

El electrocardiograma en la amiloidosis cardíaca: un arma para la sospecha diagnóstica de esta enfermedad / The electrocardiogram in cardiac amyloidosis: a weapon for the diagnosis suspect of this disease / O electrocardiograma na amiloidose cardíaca: uma arma para a suspeita diagnóstica desta doença

La amiloidosis cardíaca (AC) es una enfermedad con mal pronóstico si el tratamiento no se inicia de forma temprana, por lo que una de las asignaturas pendientes en esta enfermedad consiste en realizar un diagnóstico precoz. El electrocardiograma (ECG) es una prueba diagnóstica de bajo costo y amplia disponibilidad que nos permite sospechar esta enfermedad, dado que resulta normal en < 5% de los pacientes. El hallazgo clásico es la presencia de bajos voltajes en relación con la gran hipertrofia que se observa en las pruebas de imagen, así como el conocido patrón de pseudoinfarto. Ambos hallazgos son más frecuentes en el subtipo de amiloidosis por cadenas ligeras, que era el más frecuentemente diagnosticado en el pasado. Sin embargo, con la expansión del diagnóstico no invasivo del subtipo a transtiretina, su identificación ha crecido de forma exponencial y se convirtió en el más diagnosticado con más frecuencia en nuestro medio. Se debe prestar especial atención a todos estos hallazgos electrocardiográficos, con el fin de que esta prueba diagnóstica de sencilla obtención pueda contribuir de forma importante a la sospecha y al diagnóstico precoz de la AC.

Cardiac amyloidosis (CA) is a serious disease with a poor prognosis if treatment is not started early, so one of the pending issues in this condition is to make an early diagnosis. The electrocardiogram (EKG) is an inexpensive and widely available diagnostic test that can offer differential data when suspecting this disease, being normal in < 5% of these patients. The classic EKG finding is the presence of low voltages in relation to the large hypertrophy seen on imaging tests, as well as the well-known pseudoinfarct pattern. Both findings are more frequent in the light chain subtype of CA, which was the most frequently diagnosed in the past. However, with the growth of noninvasive diagnostic tests, the identification of the transtyretin subtype has grown exponentially, becoming the most frequently diagnosed in our setting. Special attention should be paid to all these electrocardiographic findings, so that this simple diagnostic test can make an important contribution to the early suspicion and diagnosis of CA.

A amiloidose cardíaca (AC) é uma doença grave com um mau prognóstico no caso de não se iniciar tratamento de forma precoce, pelo que a necessidade de um pronto diagnóstico é imperiosa. Quando se suspeita desta doença, o eletrocardiograma (ECG) é um teste de diagnóstico pouco dispendioso e disponível em todo o mundo, que pode fornecer dados discriminativos importantes, sendo normal em menos de 5% dos casos. O achado clássico do ECG é a presença de baixas voltagens em relação à grande hipertrofia vista na imagem, bem como o conhecido padrão de pseudoinfarte. Ambos os resultados são mais frequentes no subtipo a cadenas ligeras, o mais frequentemente diagnosticado no passado. No entanto, com o aumento dos testes de diagnóstico não-invasivos, o diagnóstico ddo subtipo a transtirretina, o mais cresceu de forma exponencial, tornando-se o mais frequentemente diagnosticado no nosso meio. Deve ser dada especial atenção a todos estes achados eletrocardiográficos já que esta prova de diagnóstico de fácil obtenção pode contribuir de forma importante para a suspeição de diagnóstico precoce de AC.

Electrocardiographic changes and changes in cardiac lactate and troponin I levels associated with search and rescue physical activity in military dogs / Alterações eletrocardiográficas e nos níveis de lactato e troponina I cardíaca associadas à atividade física de busca e salvamento em cães militares

Rescue and recovery dogs intercalate the activity intensity developed, which also triggers significant metabolic changes in cardiac physiology. Thus, we evaluated the changes that search simulation causes in glucose, lactate, and cardiac troponin I level (cTnI) and the electrocardiographic and heart rate during the activity and recovery phase to predict the physiological adaptation to the exercise. Five healthy adult dogs from the Rescue and Recovery Service of Military Firefighters Corps were submitted to 60 minutes search operation simulation in the woods. They covered a forest area of approximately 50,000 m2. The dogs were loose and accompanied by their driver, and they could perform any physical activity. Were evaluated serum biochemical analysis of glucose, lactate, cardiac troponin I, electrocardiographic, and heart rate (rest, exercise phase, and recovery time). No changes in glucose levels, heart rate, and cardiac rhythm were detected. In comparison to baseline values, there is an increase: in lactate at the end of the exercise phase [EXER] (60'EXER), and in the recovery phase [RCT] at 30'RCT and 60'RCT, and cTnI at 60'RCT, 120'RCT, and 4hRCT. P wave duration was significantly higher at 60'EXER, 15'RCT, and 30'RCT, with no alterations in wave amplitude. QRS interval duration significantly increased at 30'RCT, and the ST segment presented a significant difference at 60'EXER, 15'RCT, and 60'RCT compared to the rest moment. The moderate alterations in lactate and cTnI and few alterations in the electrocardiographic and heart rate maintenance suggest the adaptation of rescue and recovery dogs to the type, intensity, and duration of search operation simulation performed.(AU)

Cães de busca e resgate intercalam a intensidade da atividade desenvolvida que desencadeia alterações metabólicas significativas, bem como na fisiologia cardíaca. Assim, foram avaliadas as alterações que a simulação de busca produz nos níveis de glicose, lactato, troponina I cardíaca (cTnI), bem como na frequência cardíaca e atividade eletrocardiográfica durante a fase de atividade e recuperação, a fim de predizer a adaptação fisiológica ao exercício. Cinco cães adultos saudáveis do Serviço de Resgate e Salvamento do Corpo de Bombeiros Militares foram submetidos à simulação de operação de busca de 60 minutos na mata e cobriram uma área florestal de aproximadamente 50.000 m2. Os cães estavam soltos, acompanhados pelo condutor e estavam livres para realizar qualquer tipo de atividade física. Foram avaliados os níveis séricos de glicose, lactato e troponina I cardíaca, atividade eletrocardiográfica e frequência cardíaca em repouso, na fase de exercício e no tempo de recuperação. Não foram detectadas alterações nos níveis de glicose, frequência cardíaca e ritmo cardíaco. Em comparação com os valores basais houve aumento de lactato ao final da fase de exercício [EXER] (60'EXER) e na fase de recuperação [RCT] aos 30'RCT e 60'RCT; e cTnI aos 60'RCT, 120'RCT e 4hRCT. Duração da onda P foi significativamente maior em 60'EXER, 15'RCT e 30'RCT, sem alterações na amplitude da onda. Duração do intervalo QRS teve aumento significativo em 30'RCT e o segmento ST apresentou diferença significativa em 60'EXER, 15'RCT e 60'RCT quando comparado ao basal. As alterações moderadas nos níveis de lactato e cTnI, bem como a pouca alteração na atividade eletrocardiográfica e manutenção da frequência cardíaca sugerem boa adaptação dos cães de busca e resgate ao tipo, intensidade e duração da operação de busca simulada realizada.(AU)

Uso da inteligência artificial aplicada ao Eletrocardiograma para diagnóstico de Disfunção Sistólica Ventricular Esquerda / Use of artificial intelligence applied to the Electrocardiogram to diagnose Left Ventricular Systolic Dysfunction

INTRODUÇÃO: a insuficiência cardíaca (IC) é uma das três causas mais comuns de doenças cardiovasculares (DCV), grupo de enfermidades que é a principal causa de morbimortalidade no mundo. O eletrocardiograma (ECG) é um dos exames utilizados na avaliação da IC, sendo de baixo custo e amplamente acessível. Quando associado à inteligência artificial, o ECG pode ser uma poderosa ferramenta para triagem de indivíduos com maior probabilidade de IC. O objetivo foi avaliar o desempenho de um algoritmo de IA, aplicado ao ECG, para detecção de DSVE e compará-lo ao das alterações maiores ao ECG (AME), de acordo com o código de Minnesota. MÉTODOS: estudo transversal retrospectivo de acurácia diagnóstica que utilizou a população do Estudo Longitudinal da Saúde do Adulto (ELSA-Brasil). Foram avaliados 2567 indivíduos que possuíam ecocardiograma (ECO) e ECG válidos e valores de predição para disfunção sistólica do ventrículo esquerdo (DSVE) estimadas por um algoritmo de inteligência artificial (IA). A DSVE foi definida como Fração de Ejeção do Ventrículo Esquerdo (FEVE) menor que 40%, calculada utilizando o ECO. A prevalência de DSVE foi de 1,13% na população estudada (29 indivíduos). Foram calculados sensibilidade, especificidade, valor preditivo positivo (VPP), valor preditivo negativo (VPN), razão de verossimilhança positivo (RVP), razão de verossimilhança negativa (RVN), diagnostic odds ratio (DOR) para o algoritmo e para as AME. Calculou-se também a área sob a curva ROC (ASC-ROC) para o algoritmo. RESULTADOS: a população estudada possui mediana de 62 anos, sendo 47,2% do sexo masculino. A ASC-ROC do algoritmo para predição de IC foi de 0,947 (IC 95% 0,913 ­ 0,981). A sensibilidade, especificidade, VPP, VPN, RVP, RVN e DOR para o algoritmo foi de 0,690; 0,976; 0,244; 0,996; 27,6; 0,32 e 88,74, respectivamente. Para as AME foi 0,172; 0,837; 0,012; 0,989; 1,09; 0,990 e 1,07 respectivamente. CONCLUSÕES: A IA aplicada ao ECG é uma fermenta promissora para identificação de pacientes com maior probabilidade de IC e que devem ser priorizados para realização de ECO. Isso poderia aprimorar o diagnóstico de IC em nosso meio e, assim, permitir o início precoce do tratamento, com possível impacto na redução da morbidade e mortalidade.

INTRODUCTION: Heart failure (HF) is one of the three most common causes of cardiovascular diseases (CVD), which are the leading causes of morbidity and mortality worldwide. The electrocardiogram (ECG) is one of the tests used in the evaluation of HF, combining low-cost and wide accessibility. When combined with artificial intelligence, the ECG can be a powerful tool for screening individuals with a higher risk of HF. Our objective was to assess the performance of an AI algorithm applied to the ECG for the detection of left ventricular systolic dysfunction (LVSD) and compare it to the performance of major ECG abnormalities (MEA) according to the Minnesota code. METHODS: This was a retrospective cross-sectional diagnostic accuracy study using data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brazil). A total of 2567 individuals with valid echocardiograms (ECO) and ECGs and probability values for left ventricular systolic dysfunction (LVSD) estimated by an artificial intelligence (AI) algorithm, were evaluated. LVSD was defined as a left ventricular ejection fraction (LVEF) less than 40%, calculated using ECO. The prevalence of LVSD was 1.13% in the studied population (29 individuals). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated for the algorithm and MEA. The area under the ROC curve (AUC-ROC) was also calculated for the algorithm. RESULTS: The study population had a median age of 62 years, with 47.2% being male. The AUC-ROC for the algorithm to predict HF was 0.947 (95% CI 0.913 ­ 0.981). Sensitivity, specificity, PPV, NPV, PLR, NLR, and DOR for the algorithm were 0.690, 0.976, 0.244, 0.996, 27.6, 0.32, and 88.74, respectively. For MEA, it was 0.172, 0.837, 0.012, 0.989, 1.09, 0.990, and 1.07, respectively. CONCLUSIONS: AI applied to the ECG is a promising tool for identifying patients with a higher likelihood of HF who should be prioritized for ECO. This could improve the diagnosis capacity of HF in our setting and thus enable early treatment initiation, with possible impact on reducing morbidity and mortality.

El "vetusto" electrocardiograma sigue aportando nuevas variables para la asistencia y educación médicas / The "old" electrocardiogram continues to provide new variables for medical care and education

El descubrimiento de la electrocardiografía marcó un hito para la medicina: ofreció una mejor comprensión de la fisiología cardiovascular, es una herramienta imprescindible para el diagnóstico, evaluación y estratificación pronóstica de casi la totalidad de las enfermedades cardiovasculares, y ha sido un componente insustituible de las investigaciones cardiológicas de la medicina contemporánea. Importantes investigaciones de la cátedra de Cardiología del Hospital Universitario Cardiocentro "Ernesto Guevara" la han tenido como objeto de estudio en consonancia con las directrices del sistema de salud, para su aplicación en la asistencia y la actualización de los programas de la especialidad, los que se han enriquecido con nuevas variables electrocardiográficas denominadas como "no clásicas". Es objetivo de los autores comunicar algunos resultados científicos novedosos de investigaciones relacionadas con este vetusto medio de diagnóstico, los que han sido publicadas en revistas de alto impacto.

The discovery of electrocardiography marked a milestone for medicine: it offered a better understanding of cardiovascular physiology and has been an essential tool for the diagnosis, evaluation, and prognostic stratification of almost all cardiovascular diseases, and it has been an irreplaceable component of cardiology research in contemporary medicine. Important investigations of the Cardiology professorship of the "Ernesto Guevara" University Hospital have had it as an object of study in line with the guidelines of the health system, for its application in assistance and updating of specialty programs, which have been enriched with new electrocardiographic variables called "non-classical". It is the objective of the authors to communicate some novel scientific results of investigations related to this ancient aid of diagnosis, which have been published in high-impact journals.

Suxiao Jiuxin Pills Prevent Ventricular Fibrillation from Inhibiting L-type Calcium Currents CaV1.2 in vivo and in vitro / 中国结合医学杂志

OBJECTIVE@#To investigate whether Suxiao Jiuxin Pills (SJP), a Chinese herbal remedy, is an anti-ventricular fibrillation (VF) agent.@*METHODS@#VF was induced by isoproterenolol (ISO) intraperitoneal injection followed by electrical pacing in mice and rabbits. The effects of SJP on the L-type calcium channel current (CaV1.2), voltage-dependent sodium channel current (INa), rapid and slow delayed rectifier potassium channel current (IKr and IKs, respectively) were studied by whole-cell patch-clamp method. Computer simulation was implemented to incorporate the experimental data of SJP effects on the CaV1.2 current into the action potential (AP) and pseudo-electrocardiography (pseudo-ECG) models.@*RESULTS@#SJP prevented VF induction and reduced VF durations significantly in mice and rabbits. Patch-clamp experiments revealed that SJP decreased the peak amplitude of the CaV1.2 current with a half maximal concentration (IC50) value of 16.9 mg/L (SJP-30 mg/L, -32.8 ± 6.1 pA; Verapamil, -16.2 ±1.8 pA; vs. control, -234.5 ±16.7 pA, P<0.01, respectively). The steady-state activation curve, inactivation curve, and the recovery from inactivation of the CaV1.2 current were not shifted significantly. Specifically, SJP did not altered INa, IKr, and IKs currents significantly (SJP vs. control, P>0.05). Computer simulation showed that SJP-reduced CaV1.2 current shortened the AP duration, transiting VF into sinus rhythm in pseudo-ECG.@*CONCLUSION@#SJP reduced VF via inhibiting the CaV1.2 current with in vivo, in vitro, and in silico studies, which provide experimental basis for SJP anti-VF clinical application.

Association between clinical phenotypes of hypertrophic cardiomyopathy and Ca2+ gene variation gene variation / 中华心血管病杂志

Objective: To observe the association between clinical phenotypes of hypertrophic cardiomyopathy (HCM) patients and a rare calcium channel and regulatory gene variation (Ca2+ gene variation) and to compare clinical phenotypes of HCM patients with Ca2+ gene variation, a single sarcomere gene variation and without gene variation and to explore the influence of rare Ca2+ gene variation on the clinical phenotypes of HCM. Methods: Eight hundred forty-two non-related adult HCM patients diagnosed for the first time in Xijing Hospital from 2013 to 2019 were enrolled in this study. All patients underwent exon analyses of 96 hereditary cardiac disease-related genes. Patients with diabetes mellitus, coronary artery disease, post alcohol septal ablation or septal myectomy, and patients who carried sarcomere gene variation of uncertain significance or carried>1 sarcomere gene variation or carried>1 Ca2+ gene variation, with HCM pseudophenotype or carrier of ion channel gene variations other than Ca2+ based on the genetic test results were excluded. Patients were divided into gene negative group (no sarcomere or Ca2+ gene variants), sarcomere gene variation group (only 1 sarcomere gene variant) and Ca2+ gene variant group (only 1 Ca2+ gene variant). Baseline data, echocardiography and electrocardiogram data were collected for analysis. Results: A total of 346 patients were enrolled, including 170 patients without gene variation (gene negative group), 154 patients with a single sarcomere gene variation (sarcomere gene variation group) and 22 patients with a single rare Ca2+ gene variation (Ca2+ gene variation group). Compared with gene negative group, patients in Ca2+ gene variation group had higher blood pressure and higher percentage of family history of HCM and sudden cardiac death (P<0.05); echocardiographic results showed that patients in Ca2+ gene variation group had thicker ventricular septum ((23.5±5.8) mm vs. (22.3±5.7) mm, P<0.05); electrocardiographic results showed that patients in Ca2+ gene variation group had prolonged QT interval ((416.6±23.1) ms vs. (400.6±47.2) ms, P<0.05) and higher RV5+SV1 ((4.51±2.26) mv vs. (3.50±1.65) mv, P<0.05). Compared with sarcomere gene variation group, patients in Ca2+ gene variation group had later onset age and higher blood pressure (P<0.05); echocardiographic results showed that there was no significant difference in ventricular septal thickness between two groups; patients in Ca2+ gene variation group had lower percentage of left ventricular outflow tract pressure gradient>30 mmHg (1 mmHg=0.133 kPa, 22.8% vs. 48.1%, P<0.05) and the lower early diastolic peak velocity of the mitral valve inflow/early diastolic peak velocity of the mitral valve annulus (E/e') ratio ((13.0±2.5) vs. (15.9±4.2), P<0.05); patients in Ca2+ gene variation group had prolonged QT interval ((416.6±23.1) ms vs. (399.0±43.0) ms, P<0.05) and lower percentage of ST segment depression (9.1% vs. 40.3%, P<0.05). Conclusion: Compared with gene negative group, the clinical phenotype of HCM is more severe in patients with rare Ca2+ gene variation; compared with patients with sarcomere gene variation, the clinical phenotype of HCM is milder in patients with rare Ca2+ gene variation.

A single-centre experience of His bundle pacing without electrophysiological mapping system: implant success rate, safety, pacing characteristics and one-year follow up

INTRODUCTION@#Despite the challenges related to His bundle pacing (HBP), recent data suggest an improved success rate with experience. As a non-university, non-electrophysiology specialised centre in Singapore, we report our experiences in HBP using pacing system analyser alone.@*METHODS@#Data of 28 consecutive patients who underwent HBP from August 2018 to February 2019 was retrospectively obtained. The clinical and technical outcomes of these patients were compared between two timeframes of three months each. Patients were followed up for 12 months.@*RESULTS@#Immediate technical success was achieved in 21 (75.0%) patients (mean age 73.3 ± 10.7 years, 47.6% female). The mean left ventricular ejection fraction was 53.9% ± 12.1%. The indications for HBP were atrioventricular block (n = 13, 61.9%), sinus node dysfunction (n = 7, 33.3%) and upgrade from implantable cardioverter-defibrillator to His-cardiac resynchronisation therapy (n = 1, 4.8%). No significant difference was observed in baseline characteristics between Timeframe 1 and Timeframe 2. Improvements pertaining to mean fluoroscopy time were achieved between the two timeframes. There was one HBP-related complication of lead displacement during Timeframe 1. All patients with successful HBP achieved non-selective His bundle (NSHB) capture, whereas only eight patients had selective His bundle (SHB) capture. NSHB and SHB capture thresholds remained stable at the 12-month follow-up.@*CONCLUSION@#Permanent HBP is feasible and safe, even without the use of an electrophysiology recording system. This was successfully achieved in 75% of patients, with no adverse clinical outcomes during the follow-up period.

Validation of MyDiagnostick tool to identify atrial fibrillation in a multi-ethnic Asian population

INTRODUCTION@#MyDiagnostick is an atrial fibrillation (AF) screening tool that has been validated in the Caucasian population in the primary care setting.@*METHODS@#In our study, we compared MyDiagnostick with manual pulse check for AF screening in the community setting.@*RESULTS@#In our cohort of 671 candidates from a multi-ethnic Asian population, AF prevalence was found to be 1.78%. Of 12 candidates, 6 (50.0%) had a previous history of AF and another 6 (50.0%) were newly diagnosed with AF. Candidates found to have AF during the screening were older (72.0 ± 11.7 years vs. 56.0 ± 13.0 years, P < 0.0001) and had a higher CHADSVASC risk score (2.9 ± 1.5 vs. 1.5 ± 1.1, P = 0.0001). MyDiagnostick had a sensitivity of 100.0% and a specificity of 96.2%. In comparison, manual pulse check had a sensitivity of 83.3% and a specificity of 98.9%.@*CONCLUSION@#MyDiagnostick is a simple AF screening device that can be reliably used by non-specialist professionals in the community setting. Its sensitivity and specificity are comparable and validated across various studies performed in different population cohorts.

Anesthesia Depth Monitoring Based on Anesthesia Monitor with the Help of Artificial Intelligence / 中国医疗器械杂志

OBJECTIVE@#To use the low-cost anesthesia monitor for realizing anesthesia depth monitoring, effectively assist anesthesiologists in diagnosis and reduce the cost of anesthesia operation.@*METHODS@#Propose a monitoring method of anesthesia depth based on artificial intelligence. The monitoring method is designed based on convolutional neural network (CNN) and long and short-term memory (LSTM) network. The input data of the model include electrocardiogram (ECG) and pulse wave photoplethysmography (PPG) recorded in the anesthesia monitor, as well as heart rate variability (HRV) calculated from ECG, The output of the model is in three states of anesthesia induction, anesthesia maintenance and anesthesia awakening.@*RESULTS@#The accuracy of anesthesia depth monitoring model under transfer learning is 94.1%, which is better than all comparison methods.@*CONCLUSIONS@#The accuracy of this study meets the needs of perioperative anesthesia depth monitoring and the study reduces the operation cost.

Fetal electrocardiogram signal extraction and analysis method combining fast independent component analysis algorithm and convolutional neural network / 生物医学工程学杂志

Fetal electrocardiogram (ECG) signals provide important clinical information for early diagnosis and intervention of fetal abnormalities. In this paper, we propose a new method for fetal ECG signal extraction and analysis. Firstly, an improved fast independent component analysis method and singular value decomposition algorithm are combined to extract high-quality fetal ECG signals and solve the waveform missing problem. Secondly, a novel convolutional neural network model is applied to identify the QRS complex waves of fetal ECG signals and effectively solve the waveform overlap problem. Finally, high quality extraction of fetal ECG signals and intelligent recognition of fetal QRS complex waves are achieved. The method proposed in this paper was validated with the data from the PhysioNet computing in cardiology challenge 2013 database of the Complex Physiological Signals Research Resource Network. The results show that the average sensitivity and positive prediction values of the extraction algorithm are 98.21% and 99.52%, respectively, and the average sensitivity and positive prediction values of the QRS complex waves recognition algorithm are 94.14% and 95.80%, respectively, which are better than those of other research results. In conclusion, the algorithm and model proposed in this paper have some practical significance and may provide a theoretical basis for clinical medical decision making in the future.

Latest incidence and electrocardiographic predictors of atrial fibrillation: a prospective study from China / 中华医学杂志(英文版)

BACKGROUND@#China bears the biggest atrial fibrillation (AF) burden in the world. However, little is known about the incidence and predictors of AF. This study aimed to investigate the current incidence of AF and its electrocardiographic (ECG) predictors in general community individuals aged over 60 years in China.@*METHODS@#This was a prospective cohort study, recruiting subjects who were aged over 60 years and underwent annual health checkups from April to July 2015 in four community health centers in Songjiang District, Shanghai, China. The subjects were then followed up from 2015 to 2019 annually. Data on sociodemographic characteristics, medical history, and the resting 12-lead ECG were collected. Kaplan-Meier curve was used for showing the trends in AF incidence and calculating the predictors of AF. Associations of ECG abnormalities and AF incidence were examined using Cox proportional hazard models.@*RESULTS@#This study recruited 18,738 subjects, and 351 (1.87%) developed AF. The overall incidence rate of AF was 5.2/1000 person-years during an observation period of 67,704 person-years. Multivariable Cox regression analysis indicated age (hazard ratio [HR], 1.07; 95% confidence interval [CI]: 1.06-1.09; P < 0.001), male (HR, 1.30; 95% CI: 1.05-1.62; P = 0.018), a history of hypertension (HR, 1.55; 95% CI: 1.23-1.95; P < 0.001), a history of cardiac diseases (HR, 3.23; 95% CI: 2.34-4.45; P < 0.001), atrial premature complex (APC) (HR, 2.82; 95% CI: 2.17-3.68; P < 0.001), atrial flutter (HR, 18.68; 95% CI: 7.37-47.31; P < 0.001), junctional premature complex (JPC) (HR, 3.57; 95% CI: 1.59-8.02; P = 0.002), junctional rhythm (HR, 18.24; 95% CI: 5.83-57.07; P < 0.001), ventricular premature complex (VPC) (HR, 1.76; 95% CI: 1.13-2.75, P = 0.012), short PR interval (HR, 5.49; 95% CI: 1.36-22.19; P = 0.017), right atrial enlargement (HR, 6.22; 95% CI: 1.54-25.14; P = 0.010), and pacing rhythm (HR, 3.99; 95% CI: 1.57-10.14; P = 0.004) were independently associated with the incidence of AF.@*CONCLUSIONS@#The present incidence of AF was 5.2/1000 person-years in the studied population aged over 60 years in China. Among various ECG abnormalities, only APC, atrial flutter, JPC, junctional rhythm, short PR interval, VPC, right atrial enlargement, and pacing rhythm were independently associated with AF incidence.

Approach to bradyarrhythmias: A proposed algorithm

Bradyarrhythmias are commonly encountered in clinical practice. While there are several electrocardiographic criteria and algorithms for tachyarrhythmias, there is no algorithm for bradyarrhythmias to the best of our knowledge. In this article, we propose a diagnostic algorithm that uses simple concepts: (1) the presence or absence of P waves, (2) the relationship between the number of P waves and QRS complexes, and (3) the regularity of time intervals (PP, PR and RR intervals). We believe this straightforward, stepwise method provides a structured and thorough approach to the wide differential diagnosis of bradyarrhythmias, and in doing so, reduces misdiagnosis and mismanagement.

Summary of evidence for threshold setting of multi-parameter electrocardiograph monitor in intensive care unit / 中华危重病急救医学

OBJECTIVE@#To retrieve the evidence for threshold setting of multi-parameter electrocardiograph (ECG) monitors in intensive care unit (ICU), and summarize the best evidence.@*METHODS@#After literature retrieval, clinical guidelines, expert consensus, evidence summary and systematic review that met the requirements were screened. Guidelines were evaluated by the appraisal of guidelines for research and evaluation II (AGREE II), expert consensus and systematic review were evaluated by the Australian JBI evidence-based health care center authenticity evaluation tool, and evidence summary was evaluated by the CASE checklist. High-quality literature was selected to extract evidence related to the use and setup of multi-parameter ECG monitors in the ICU.@*RESULTS@#A total of 19 literatures were included, including 7 guidelines, 2 expert consensus, 8 systematic reviews, 1 evidence summary, and 1 national industry standard. After evidence extraction, translation, proofreading and summary, a total of 32 pieces of evidence were integrated. The included evidence involved the environmental preparation for the application of the ECG monitor, the electrical requirements of the ECG monitor, ECG monitor use process, ECG monitor alarm setting principles, ECG monitor alarm heart rate or heart rhythm monitoring setting, ECG monitor alarm blood pressure monitoring setting, ECG monitor alarm respiratory and blood oxygen saturation threshold setting, alarm delay warning time setting, adjusting alarm setting method, evaluating alarm setting time, improving the comfort of monitoring patients, reducing nuisance alarm report the occurrence, alarm priority processing, alarm intelligent processing and so on.@*CONCLUSIONS@#This summary of evidence involves many aspects of the setting and application of ECG monitor. According to the latest guidelines and expert consensus, it is updated and revised to guide healthcare workers to monitor patients more scientifically and safely, and aims to ensure patient safety.