Síndrome de QT largo congénito y bradicardia fetal: la importancia del diagnóstico / Congenital long QT syndrome and fetal bradycardia: the importance of the diagnosis

Antecedentes: El síndrome de QT largo es una canalopatía que afecta a la repolarización ventricular y aumenta el riesgo de sufrir arritmias ventriculares graves. Puede ser congénito o adquirido, y es una causa conocida de muerte súbita. Caso clínico: Gestante primigesta, de 28 años, sin antecedentes de interés. En ecografías prenatales se objetivó en el feto bradicardia sinusal mantenida desde la semana 28, sin repercusión hemodinámica, que persistió hasta la finalización de la gestación (semana 37+3). Al nacimiento se realizaron electrocardiogramas seriados que mostraron alteraciones en la repolarización con alargamiento del intervalo QT corregido. Se realizó estudio genético que confirmó síndrome de QT largo tipo 1 y se inició tratamiento oral con beta-bloqueantes, con buena respuesta. Conclusiones: El síndrome de QT largo suele diagnosticarse posnatalmente. Es importante conocer sus características clínicas prenatales para poder establecer un diagnóstico precoz y minimizar así el riesgo de muerte súbita de estos pacientes.

Background: Long QT syndrome is a channelopathy that affects ventricular repolarization and increases the risk of severe ventricular arrhythmias. It can be congenital or acquired, and is a known cause of sudden cardiac death. Case report: A 28-year-old primigravida with no significant medical history. Prenatal ultrasounds revealed sustained fetal sinus bradycardia from week 28, without hemodynamic repercussion, which persisted until the end of gestation (at 37+3 weeks). Serial electrocardiograms were performed after birth, showing repolarization abnormalities with prolonged corrected QT interval. A genetic study confirmed long QT syndrome type 1, and oral treatment with beta-blockers was initiated, showing a positive response. Conclusions: Long QT syndrome is often diagnosed postnatally. It is important to be aware of his prenatal clinical features in order to establish an early diagnosis and minimize the risk of sudden death in these patients.

Teachable moments in ECG: The physiology behind the pattern

@#The electrocardiographic analysis of heart blocks provides great opportunities for the discussion of mechanisms of electrical cardiac conduction, serving as “teachable moments” in medicine. Recognition of heart blocks can sometimes be a challenge as they can present in many forms, different severities and levels of blocks that present as varied patterns on electrocardiographic tracing. The ultimate key to correct diagnosis rests on adequate understanding of normal electrophysiology of the electrical system of the heart. While it is vital to recognize the pattern, we should always know and understand the physiology behind the pattern. This article presents a detailed analysis of a case of heart block which can easily be misinterpreted on first look. The case is featured not for its rarity but for the interesting concepts in cardiac electrophysiology that are highlighted. Navigation of the different elements of tracing can be an adventure and a great learning experience enjoyed by both students and experts.

¿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)

Bloqueo aurículoventricular en la granulomatosis con poliangeítis (Granulomatosis de Wegener). Caso clínico y revisión de la literatura / Atrioventricular block in granulomatosis with polyangiitis (Wegener's granulomatosis). Case report and review of literature

La Granulomatosis con Poliangeítis (GPA), o Granulomatosis de Wegener, es una vasculitis sistémica de pequeño y mediano vaso inmunológicamente mediada, que preferentemente compromete la vía aérea superior, pulmones y riñones, y es poco frecuente que se asocie a manifestaciones cardíacas. El compromiso del sistema éxcitoconductor (SEC) es muy raro y se han descrito casos aislados de distintos grados de bloqueo aurículoventricular (BAV). Describimos el caso de un paciente con GPA que durante una recidiva de su enfermedad consultó por disnea, documentándose signos de bajo débito, bradicardia de 30/ min, BAV de 2° grado avanzado y bloqueo completo de rama izquierda (BCRI) en el electrocardiograma (ECG). Se presenta una revisión de la literatura y discutimos sus causas, la evolución y manejo de estos pacientes.

Granulomatosis with Polyangiitis (GPA), or Wegener's Granulomatosis, is an immunologically mediated systemic vasculitis of small and medium vessels, which commonly compromises the upper airway, lungs, and kidneys and is rarely associated with cardiac manifestations. Compromise of the cardiac conduction system is rare, and isolated cases of different degrees of atrioventricular block (AVB) have been described. We report a case of a 49-year-old male patient previously diagnosed with GPA 3 years ago, who presented to the emergency department with dyspnea, clinical signs of low output, bradycardia of 30/min, advanced second-degree AVB and complete left bundle branch block (LBBB) on the ECG. A literature review is presented, and we discuss the causes, evolution, and management of this GPA complication.

Taquicardia ventricular polimórfica tipo torsadess de pointes secundaria a estimulación por marcapasos / Polymorphic ventricular taquicardia "torsades de pointes" associated to abnormal pacemaker stimulation

La taquicardia ventricular polimórfica se origina en los ventrículos, cuyos complejos QRS son de morfología, amplitud y dirección variable, con frecuencias que oscilan entre 200 y 250 lpm, pudiendo ser autolimitadas o degenerar en una fibrilación ventricular. La TdP es un tipo de taquicardia ventricular polimórfica caracterizada por complejos con un eje eléctrico que gira alrededor de la línea isoeléctrica y que está asociada a QT largo. Se presenta el caso de una paciente portadora de marcapaso que presenta episodios de taquicardia ventricular polimórfica, con una morfología típica de TdP, sin documentación de QT prolongado previo ni actual, generada por la estimulación ventricular sobre onda T, de forma accidental por desplazamiento del electrodo auricular a Ventrículo Derecho (VD).

Polymorphic ventricular tachycardia is a tachycardia originating in the ventricles, where the QRS complexes have variable morphology, amplitude, and direction, with frequencies ranging between 200 and 250 bpm; it may be self-limited or degenerate into ventricular fibrillation. Torsades de Pointes (TdP) is a type of polymorphic ventricular tachycardia characterized by complexes with an electrical axis that rotates around the isoelectric line and that is associated with long QT interval. We present the case of a patient with a pacemaker who presents episodes of polymorphic ventricular tachycardia, with a typical morphology of TdP, without documentation of previous or current prolonged QT, generated by ventricular stimulation on the T wave, accidentally due to displacement of the atrial electrode to the Right Ventricle (RV).

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)

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.

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.

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.