Diferenças entre Duas Condições Cardíacas Hipertróficas Distintas: Doença de Fabry Versus Cardiomiopatia Hipertrófica / Differences Between Two Distinct Hypertrophic Cardiac Conditions: Fabry Disease versus Hypertrophic Cardiomyopathy

Resumo Fundamento A cardiomiopatia hipertrófica (CMH) e a doença de Fabry (DF) são doenças herdadas geneticamente com características fenotípicas de hipertrofia ventricular esquerda (HVE) que causam resultados cardíacos adversos. Objetivos Investigar as diferenças demográficas, clínicas, bioquímicas, eletrocardiográficas (ECG) e ecocardiográficas (ECO) entre CMH e DF. Métodos 60 pacientes com CMH e 40 pacientes com DF foram analisados retrospectivamente como uma subanálise do "estudo LVH-TR" após exclusão de pacientes com fibrilação atrial, ritmo de estimulação, bloqueios de ramo e bloqueios atrioventriculares (AV) de segundo e terceiro graus. O nível de significância foi aceito como <0,05. Resultados O sexo masculino (p=0,048) e a creatinina (p=0,010) são significativamente maiores a favor da DF; entretanto, infradesnivelamento do segmento ST (p=0,028), duração do QT (p=0,041), espessura do septo interventricular (SIVd) (p=0,003), espessura da parede posterior (PWd) (p=0,009), insuficiência mitral moderada a grave (IM) (p=0,013) e o índice de massa ventricular esquerda (IMVE) (p=0,041) são significativamente maiores a favor da CMH nas análises univariadas. Na análise multivariada, a significância estatística apenas permanece na creatinina (p=0,018) e na duração do intervalo QT (0,045). A DF foi positivamente correlacionada com a creatinina (rho=0,287, p=0,004) e a CMH foi positivamente correlacionada com o PWd (rho=0,306, p=0,002), IVSd (rho=0,395, p<0,001), IM moderada-grave (rho= 0,276, p<0,005), IMVE (rho=0,300, p=0,002), espessura relativa da parede (ERP) (rho=0,271, p=0,006), duração do QT (rho=0,213, p=0,034) e depressão do segmento ST (rho =0,222, p=0,026). Conclusão Características bioquímicas, ECG e ECO específicas podem auxiliar na diferenciação e no diagnóstico precoce da CMH e da DF.

Abstract Background Hypertrophic cardiomyopathy (HCM) and Fabry disease (FD) are genetically inherited diseases with left ventricular hypertrophy (LVH) phenotype characteristics that cause adverse cardiac outcomes. Objectives To investigate the demographic, clinical, biochemical, electrocardiographic (ECG), and echocardiographic (ECHO) differences between HCM and FD. Methods 60 HCM and 40 FD patients were analyzed retrospectively as a subanalysis of the 'LVH-TR study' after excluding patients with atrial fibrillation, pace rhythm, bundle branch blocks, and second and third-degree atrioventricular (AV) blocks. The significance level was accepted as <0.05. Results Male gender (p=0.048) and creatinine (p=0.010) are significantly higher in favor of FD; however, ST depression (p=0.028), QT duration (p=0.041), interventricular septum thickness (IVSd) (p=0.003), posterior wall thickness (PWd) (p=0.009), moderate-severe mitral regurgitation (MR) (p=0.013), and LV mass index (LVMI) (p=0.041) are significantly higher in favor of HCM in the univariate analyses. In multivariate analysis, statistical significance only continues in creatinine (p=0.018) and QT duration (0.045). FD was positively correlated with creatinine (rho=0.287, p=0.004) and HCM was positively correlated with PWd (rho=0.306, p=0.002), IVSd (rho=0.395, p<0.001), moderate-severe MR (rho=0.276, p<0.005), LVMI (rho=0.300, p=0.002), relative wall thickness (RWT) (rho=0.271, p=0.006), QT duration (rho=0.213, p=0.034) and ST depression (rho=0.222, p=0.026). Conclusion Specific biochemical, ECG, and ECHO characteristics can aid in the differentiation and early diagnosis of HCM and FD.

Resource utilization and costs related to the management of obstructive hypertrophic cardiomyopathy under the Brazilian supplementary healthcare system´s perspective: results from a modified Delphi panel / Utilização de recursos e custos relacionados ao manejo da cardiomiopatia hipertrófica obstrutiva sob a perspectiva do sistema de saúde suplementar brasileiro: resultados de um painel Delphi modificado

Objective: To generate data on the costs associated with the diagnosis and treatment of obstructive ypertrophic cardiomyopathy (HCM) from the perspective of the private health system in Brazil. Methods: A modified Delphi panel including seven different specialists (three clinical cardiologists with experience in obstructive HCM, two hemodynamicists with experience in septal ablation and two cardiac surgeons with expertise in myectomy), from two Brazilian states (São Paulo and Pernambuco), was conducted between August and November 2022. Two rounds of questions about the use of healthcare resources according to the functional class (NYHA I-IV) and a panel in a virtual platform were conducted to obtain the final consensus. Micro-costing defined costs and unit values were determined based on official price lists. Results: The total diagnosis cost per patient was estimated at BRL 11,486.81. The obstructive HCM management costs analysis showed average annual costs per patient of BRL 17,026.74, BRL 19,401.46, BRL 73,310.07, and BRL 94,885.75 for the functional classes NYHA I, NYHA II, NYHA III, and NYHA IV, respectively. The average costs per patient related to procedures in a year were BRL 12,698.53, BRL 13,462.30, BRL 58,841.67, and BRL 75,595.90 for the functional classes NYHA I, II, III, and IV, respectively. Conclusions: The annual costs of HCM management increased according to the functional class, highlighting the need for safe and effective strategies to improve patient's NYHA functional class while promoting a decrease in the need for invasive therapies.

Objetivo: Gerar dados acerca dos custos associados ao diagnóstico e tratamento da cardiomiopatia hipertrófica (CMH) obstrutiva, sob a perspectiva do sistema de saúde privado no Brasil. Métodos: Um painel Delphi modificado incluindo sete especialistas (três cardiologistas clínicos com experiência em CMH obstrutiva, dois hemodinamicistas com experiência em ablação de septo e dois cirurgiões cardíacos com experiência em miectomia) de dois estados brasileiros (São Paulo e Pernambuco) foi conduzido entre agosto e novembro de 2022. Foram realizadas duas rodadas de perguntas acerca da utilização de recursos de acordo com a classe funcional (NYHA I-IV) e uma reunião virtual para obtenção do consenso final. Os custos foram definidos por meio de microcusteio, e os valores unitários foram definidos com base em listas de preço oficiais. Resultados: O custo total do diagnóstico por paciente foi estimado em R$ 11.486,81. A análise de custos de manejo da CMH obstrutiva mostrou custos médios anuais por paciente de R$ 17.026,74, R$ 19.401,46, R$ 73.310,07 e R$ 94.885,75 para as classes funcionais NYHA I, NYHA II, NYHA III e NYHA IV, respectivamente. Os custos médios por paciente relacionados a procedimentos em um ano foram de R$ 12.698,53, R$ 13.462,30, R$ 58.841,67 e R$ 75.595,90 para as classes NYHA I, II, III e IV, respectivamente. Conclusões: Os custos anuais com o manejo da CMH aumentam de acordo com a classe funcional, destacando a necessidade de estratégias seguras e eficazes capazes de melhorar a classe funcional NYHA do paciente, ao mesmo tempo que promove diminuição da necessidade de terapias invasivas.

Desfibrilador subcutáneo. Primeros casos en el Instituto Nacional de Cardiología, incluyendo dos pacientes pediátricos / Use of subcutaneous cardioverter-defibrillator. First cases reported from National Institute of Cardiology Ignacio Chávez-Mexico

Resumen Introducción: El desfibrilador automático implantable (DAI) transvenoso es el tratamiento de elección para la prevención de muerte súbita (MS) cardiaca por arritmias ventriculares malignas. Su uso se puede ver limitado cuando existe infección del sistema de estimulación o en población pediátrica donde representa un reto por diversas razones, incluyendo: las mínimas dimensiones del sistema venoso de los niños, la longitud de los electrodos, el tamaño del generador, así como por la complejidad anatómica en casos de cardiopatía congénita asociada. Objetivo: El presente artículo tiene por objetivo presentar la primera serie de casos de pacientes mexicanos a los cuales se les implantó un DAI subcutáneo (DAI-SC) como terapia para la prevención de MS. Métodos: Se presentan los cuatro primeros casos que fueron implantados en el Instituto Nacional de Cardiología Ignacio Chávez con un DAI-SC (Emblem, Boston Scientific, EE.UU.), tres de ellos eran pacientes pediátricos, incluyendo el primer implante de este tipo de dispositivo en un paciente pediátrico en América Latina. Las técnicas de tres y dos incisiones fueron empleadas bajo anestesia general. Resultados: Se realizó el implante exitoso con técnica de tres incisiones en los dos primeros casos y con técnica de dos incisiones en los dos últimos casos. Se corroboró el adecuado funcionamiento del dispositivo en sala, con la verificación de terapia apropiada (65 J) de la fibrilación ventricular inducida mediante estimulación a 50 Hz. No hubo complicaciones inmediatas. Un paciente presentó descargas apropiadas a los dos meses del implante. En el seguimiento, un niño desarrolló erosión de la piel a nivel de la curva del electrodo en el esternón, sin datos de infección. En quirófano se resecó la piel dañada, se retiró el barril y la seda de fijación, se realizó lavado quirúrgico y se volvió a cerrar la piel, logrando así evitar el retiro del sistema. Conclusiones: El DAI-SC es una terapia alternativa al DAI endovenoso y puede ser considerado de primera elección en aquellos casos que no requieran de estimulación ventricular, incluyendo pacientes pediátricos. Pueden ocurrir complicaciones cutáneas, pero no representan una amenaza como las complicaciones venosas de los DAI convencionales.

Abstract Introduction: The transvenous implantable cardioverter defibrillator (ICD) is the treatment of choice for the prevention of sudden cardiac death (SCD). Its use could be restricted when device-related infections occurs or in the pediatric population. In the later, an ICD represents a challenge, due to the minimal dimensions of the venous system in children, the length of the electrodes, the size of the generator, as well as the anatomical complexity in cases with associated congenital heart disease. Objective: This article presents the first Mexican patients with a subcutaneous ICD (SC-ICD) implant as a therapy for the prevention of SCD. Methods: The first four cases were implanted at the Ignacio Chávez National Institute of Cardiology with a SC-ICD (Emblem, Boston Scientific, USA), three of them were pediatric patients, including the first implant of this type of device in a pediatric patient in Latin America. The 3-incision and 2-incision techniques were used under general anesthesia. Results: A successful implantation was obtained with the 3-incision technique in the first 2 cases and the last 2 with the 2-incision technique. Proper functioning of the device was corroborated in the operating room with proof of appropriate therapy (65 J) for ventricular fibrillation induced with 50 Hz stimulation. No immediate complications were observed. One patient had appropriate shocks two months after the implant. During follow-up, one child developed skin erosion at the level of the curve of the electrode on the sternum, with no signs of infection. In the operating room, the damaged skin was resected, the barrel and the fixation silk were removed, surgical lavage was performed, and the skin was closed again, thus avoiding removal of the system. Conclusions: The SC-ICD is an alternative therapy to the transvenous ICD. It can be considered first choice in subjects who do not require ventricular pacing, including pediatric patients. Skin complications can occur but do not pose a threat as venous complications of conventional ICDs.

Miocardiopatía hipertrófica en la edad pediátrica. Revisión a propósito de una serie de casos

Introducción: La miocardiopatía hipertrófica (MCH) constituye una enfermedad compleja y variable en cuanto a morfología, fisiopatología, pronóstico y sobrevida. Se caracteriza por una hipertrofia del ventrículo izquierdo, aunque en ocasiones puede ser biventricular o ventricular derecha aislada. En la edad pediátrica predominan las causas no sarcoméricas. La ecocardiografía es el método diagnóstico más utilizado para caracterizar la morfología y repercusión hemodinámica, sin embargo, la resonancia magnética cardíaca (RMC) es de elección por aportar mayores ventajas morfológicas y funcionales. Las pruebas genéticas son de gran importancia en la determinación del diagnóstico etiológico, manejo terapéutico y pronóstico. El tratamiento tiene como objetivo principal mejorar la capacidad funcional y aliviar los síntomas. Los betabloqueantes no vasodilatadores son considerados de primera líneay en algunos casos se puede recurrir a terapias avanzadas como disopiramida o terapia de reducción septal (TRS), uso del cardiodesfibrilador implantable (CDI), y en ocasiones se debe considerar trasplante cardiaco en pacientes con síntomas refractarios al tratamiento médico y en MCH del tipo obstructivo. Materiales y métodos: Estudio observacional, descriptivo, corte transversal. Resultados: Se estudiaron 12 pacientes, desde enero de 2020 a diciembre de 2022, con edades comprendidas desde 5 meses hasta 16 años, diagnosticados con MCH de presentación clínica variable y de distintas etiologías. Conclusión: La MCH de causas no sarcoméricas como los síndromes malformativos y errores innatos del metabolismo son las que tienen peor pronóstico y sobrevida. La finalidad de detectar precozmente la MCH es el inicio temprano de la terapia específica, para así retrasar el compromiso cardiovascular y mejorar la sobrevida.

Introduction: Hypertrophic cardiomyopathy (HCM) is a complex and variable disease in terms of morphology, pathophysiology, prognosis and survival. It is characterized by left ventricular hypertrophy, although it can sometimes be biventricular or isolated right ventricular. In the pediatric population, non-sarcomeric causes predominate. Echocardiography is the most widely used diagnostic method to characterize morphology and hemodynamic repercussions; however, cardiac magnetic resonance imaging (CMR) is preferred because it provides greater morphological and functional advantages. Genetic tests are of great importance in determining the etiological diagnosis, therapeutic management and prognosis. The main objective of the treatment is to improve functional capacity and alleviate symptoms. Non-vasodilator beta-blockers are considered first-line treatment and in some cases advanced therapies such as disopyramide or septal reduction therapy (SRT), use of implantable cardioverter-defibrillator (ICD) can be used; heart transplantation should be considered in patients with symptoms refractory to medical treatment and in HCM of the obstructive type. Materials and methods: This was an observational, descriptive, cross-sectional study. Results: 12 patients were studied, from January 2020 to December 2022, with ages ranging from 5 months to 16 years, diagnosed with HCM of variable clinical presentation and of different etiologies. Conclusion: HCM from non-sarcomeric causes such as malformation syndromes and inborn errors of metabolism have the worst prognosis and survival. The purpose of early detection of HCM is the early initiation of specific therapy, in order to delay cardiovascular compromise and improve survival.

Echocardiographic and Etiopathogenic Features of Hypertrophic Cardiomyopathy: Casablanca University Hospital Experience

Hypertrophic cardiomyopathy (HCM) is the most common non-ischemic cardiomyopathy with a prevalence of 1:500 in the general population, based on the recognition of the phenotype. HCM is defined by the presence of increased left ventricular (LV) wall thickness that is not solely explained by abnormal loading conditions and the phenotype also includes disorganized myocyte arrangement, fibrosis, small-vessel disease, and abnormalities of the mitral valve apparatus. In particular to this pathology, we have conducted a one-year prospective study to determine clinical, echocardiographic features and etiopathogenic aspects of hypertrophic cardiomyopathy in the Casablanca university hospital. The results concluded that 50% of the causes was due to amyloidosis 35%, sarcomeric HCM and 15% Fabry disease in which 2 cases were related with pregnancy. Transthoracic echocardiography and cardia MRI plays an important role in HCM diagnosis and prognosis.

Recent research on childhood hypertrophic cardiomyopathy caused by MYH7 gene mutations / 中国当代儿科杂志

Hypertrophic cardiomyopathy (HCM) is the most common monogenic inherited myocardial disease in children, and mutations in sarcomere genes (such as MYH7 and MYBPC3) are the most common genetic etiology of HCM, among which mutations in the MYH7 gene are the most common and account for 30%-50%. MYH7 gene mutations have the characteristics of being affected by environmental factors, coexisting with multiple genetic variations, and age-dependent penetrance, which leads to different or overlapping clinical phenotypes in children, including various cardiomyopathies and skeletal myopathies. At present, the pathogenesis, course, and prognosis of HCM caused by MYH7 gene mutations in children remain unclear. This article summarizes the possible pathogenesis, clinical phenotype, and treatment of HCM caused by MYH7 gene mutations, in order to facilitate the accurate prognostic evaluation and individualized management and treatment of the children with this disorder.

Transapical approach under 3D printing guidance for myectomy in apical hypertrophic cardiomyopathy: A case report / 中国胸心血管外科临床杂志

@#We reported a 26-year-old male who was diagnosed with apical hypertrophic cardiomyopathy with left ventricular aneurysm. The location of the hypertrophic myocardium and the extent of resection were accurately assessed preoperatively using 3D modeling and printing technology. Myectomy was performed via transapical approach, and the intraoperative exploration was consistent with the description of the preoperative 3D modeling. The patient underwent the surgery successfully without any complications during the hospitalization, and the cardiopulmonary bypass time was 117 min, the aortic cross-clamping time was 57 min, and the hospital stay time was 7 d. The postoperative echocardiography demonstrated left ventricular cavity flow patency. This case provides a reference for the management of patients with apical hypertrophic cardiomyopathy.

Action mechanism of microRNA-484 involved in myocardial fibrosis in hypertrophic cardiomyopathy / 中国胸心血管外科临床杂志

@#Objective     To search for the key microRNAs (miRNAs) involved in myocardial fibrosis in hypertrophic cardiomyopathy, and to further explore the mechanisms involved in the regulation of myocardial fibrosis. Methods    Forty-two patients with hypertrophic cardiomyopathy diagnosed and treated surgically in West China Hospital of Sichuan University from January 2014 to June 2018 were selected, including 29 males and 13 females, with a median age of 46 (15-69) years. In the myocardial tissue of patients with hypertrophic cardiomyopathy with different degrees of fibrosis, miRNAs with significantly different expression were screened and further verified at the cellular level. By regulating the expression of the target miRNAs, the expressions of fibrosis-related proteins and target genes were detected respectively. Finally, the target-binding relationship was verified by dual-luciferase reporter gene detection. Results    miR-484 was up-regulated in severely fibrotic myocardial tissue and activated cardiac fibroblasts. After cardiac fibroblasts were activated by TGF-β1, the expression of miR-484 was significantly up-regulated, the expression of fibrosis-related proteins (CollagenⅠ, α-SMA) increased, and the expression of the target gene HIPK1 decreased (P<0.05). After inhibiting the expression of miR-484 by transfection of miR-484 antagomir, the expression of fibrosis-related proteins decreased, while expression of HIPK1 was up-regulated (P<0.05). The detection of dual luciferase reporter gene showed that the luciferase activity of the transfected WT-miRNA-484 mimics group was lower than that of the control group (P<0.05). Conclusion    miR-484 is a pro-fibrotic miRNA that participates in the process of myocardial fibrosis by negatively regulating the expression of HIPK1. It can be used as a regulatory target to provide a therapeutic strategy for myocardial fibrosis.

Progress in New Therapies Targeting the Pathogenesis of Cardiomyopathywith Hypertrophic Phenotype / 罕见病研究

Hypertrophic cardiomyopathy (HCM) is cardiomyopathy with a clinical phenotype of cardiac hypertrophy. The etiology includes genetically defective encoding sarcomeres, congenital metabolic diseases such as lysosomal storage diseases, systemic amyloidosis such as transthyretin amyloidosis(ATTR), and Fabry disease. Previous therapies did not target the etiology and pathogenesis and therefore were less effective. In recent years, treatments targeting different mechanisms of myocardial hypertrophy have achieved good results. Mavacamten can reduce myocardial contractility by inhibiting ATP activity, thereby significantly improving left ventricular outflow tract(LVOT) obstruction, cardiac contractility, ventricular tension, and limitting myocardial damage. By inhibiting the dissociation of transthyretin(TTR) and subsequent formation and deposition of the amyloid fibril, tafamidis can reduce the mortality and morbidity of patients with transthyretin cardiac amyloidosis(ATTR-CA). Gene silencing and gene editing technology can reduce abnormal TTR levels. Synthesis of α-galactosidase A by gene recombination technology in vitro can effectively reduce left ventricular mass index(LVMi), improve cardiac function, reduce angina attacks and decrease mortality of Fabry disease.

Machine learning modeling identifies hypertrophic cardiomyopathy subtypes with genetic signature / 医学前沿

Previous studies have revealed that patients with hypertrophic cardiomyopathy (HCM) exhibit differences in symptom severity and prognosis, indicating potential HCM subtypes among these patients. Here, 793 patients with HCM were recruited at an average follow-up of 32.78 ± 27.58 months to identify potential HCM subtypes by performing consensus clustering on the basis of their echocardiography features. Furthermore, we proposed a systematic method for illustrating the relationship between the phenotype and genotype of each HCM subtype by using machine learning modeling and interactome network detection techniques based on whole-exome sequencing data. Another independent cohort that consisted of 414 patients with HCM was recruited to replicate the findings. Consequently, two subtypes characterized by different clinical outcomes were identified in HCM. Patients with subtype 2 presented asymmetric septal hypertrophy associated with a stable course, while those with subtype 1 displayed left ventricular systolic dysfunction and aggressive progression. Machine learning modeling based on personal whole-exome data identified 46 genes with mutation burden that could accurately predict subtype propensities. Furthermore, the patients in another cohort predicted as subtype 1 by the 46-gene model presented increased left ventricular end-diastolic diameter and reduced left ventricular ejection fraction. By employing echocardiography and genetic screening for the 46 genes, HCM can be classified into two subtypes with distinct clinical outcomes.

Phenotype and genotype characteristics of children with cardiomyopathy associated with MYH7 gene mutation: a retrospective analysis / 中国当代儿科杂志

OBJECTIVES@#To investigate the clinical phenotype and genotype characteristics of children withcardiomyopathy (CM) associated with MYH7 gene mutation.@*METHODS@#A retrospective analysis was conducted on the medical data of five children with CM caused by MYH7 gene mutation who were diagnosed and treated in the Department of Cardiology, Hebei Children's Hospital.@*RESULTS@#Among the five children with CM, there were three girls and two boys, all of whom carried MYH7 gene mutation. Seven mutation sites were identified, among which five were not reported before. Among the five children, there were three children with hypertrophic cardiomyopathy, one child with dilated cardiomyopathy, and one child with noncompaction cardiomyopathy. The age ranged from 6 to 156 months at the initial diagnosis. At the initial diagnosis, two children had the manifestations of heart failure such as cough, shortness of breath, poor feeding, and cyanosis of lips, as well as delayed development; one child had palpitation, blackness, and syncope; one child had fever, runny nose, and abnormal liver function; all five children had a reduction in activity endurance. All five children received pharmacotherapy for improving cardiac function and survived after follow-up for 7-24 months.@*CONCLUSIONS@#The age of onset varies in children with CM caused by MYH7 gene mutation, and most children lack specific clinical manifestations at the initial diagnosis and may have the phenotype of hypertrophic cardiomyopathy, dilated cardiomyopathy or noncompaction cardiomyopathy. The children receiving early genetic diagnosis and pharmacological intervention result in a favorable short-term prognosis.

La miocardiopatía hipertrófica induce cambios en la expresión de la triptófano-5-hidroxilasa, el transportador de serotonina y receptores serotoninérgicos / Hypertrophic cardiomyopathy induces changes in the tryptophan-5-hydroxylase, serotonin transporter and serotonergic receptors expressions

Resumen Introducción: Los cardiomiocitos poseen la maquinaria bioquímica capaz de sintetizar, utilizar y recapturar serotonina. Objetivo: Determinar si la miocardiopatía hipertrófica (MCH) induce cambios en la expresión de la triptófano-5-hidroxilasa (TPH) 1 y 2, el transportador de serotonina (SERT) y los receptores serotoninérgicos (RS). Métodos: Estudio transversal de cinco bloques de tejido de corazones con MCH y cinco bloques de corazones de control. Se obtuvieron cinco cortes de la pared libre del ventrículo izquierdo (PLVI) y del septum interventricular (SIV) de cada bloque, para determinar la expresión de TPH1 y TPH2, SERT y RS con anticuerpos por inmunofluorescencia. La inmunofluorescencia fue evaluada mediante t de WELCH, con nivel de significación de p < 0.05. Resultados: La PLVI y el SIV de los corazones con MCH mostraron aumento de la expresión de TPH1 y TPH2, así como de los receptores 5-HT2A y 5-HT2B en comparación con los controles (p < 0.01). El receptor 5-HT4 y SERT aumentaron en el SIV de los corazones con MCH (p < 0.01). Conclusiones: Se demostró aumento de las expresiones de TPH, SERT y RS en los cardiomiocitos de los corazones con MCH en comparación con los controles, lo cual podría participar en la fisiopatología de la MCH en los humanos.

Abstract Introduction: Cardiomyocytes have a biochemical machinery with the capacity to synthesize, utilize and reuptake serotonin. Objective: To determine whether hypertrophic cardiomyopathy (HCM) induces changes in the expression of tryptophan-5-hydroxylase (TPH) 1 and 2, serotonin transporter (SERT) and serotonergic receptors (SR). Methods: Cross-sectional study of five tissue blocks from hearts with HCM and five controls. Five sections of the left ventricular free wall (LVFW) and interventricular septum (IVS) were obtained from each block to determine the expression of TPH1 and TPH2, SERT and SRs by immunofluorescence with specific antibodies. Immunofluorescence was evaluated by WELCH t-test, with a level of significance of p < 0.05. Results: LVFW and IVS of hearts with HCM showed an increase in the expression of TPH1 and TPH 2 and 5-HT2A and 5-HT2B receptors in comparison with controls (p < 0.01). The 5-HT4 receptor and SERT showed an increase in the IVS of hearts with HCM (p < 0.01). Conclusions: This study demonstrated an increased expression of TPH, SERT and SRs in cardiomyocytes from hearts with HCM in comparison with controls, which could be involved in the pathophysiology of HCM in humans.

Hypertrophic cardiomyopathy. Proposal for a new classification / Miocardiopatía hipertrófica. Propuesta de una nueva clasificación

Abstract Hypertrophic cardiomyopathy (HCM) is a clinical condition, but its name has been subjected to frequent changes over the years, largely because of its morphological and functional heterogeneity, which leads the clinician who is focused on its study to have difficulty in understanding how to diagnose it and when and how to treat it. Regarding its name, it has been called in more than 75 different ways, and it has being classified with difficulty through echocardiography for more than 40 years. Today, it is necessary to understand that the diverse phenotypic behavior, as well as the evolutionary stages of the disease, must be approached in a practical and effective way, so that it easier to understand its clinical behavior and prognosis, as well as the therapeutic needs in each particular case. We review the aspects related to the name of the condition and propose a new classification that could provide the clinical and surgical cardiologist a better understanding of HCM in its various morphological and functional aspects.

Resumen La Miocardiopatía Hipertrófica es una entidad clínica que ha sido sometida durante años a cambios frecuentes en su denominación, en gran parte consecuencia de su heterogeneidad morfológica y funcional, lo que hace que el clínico enfocado a su estudio, tenga dificultad en el entendimiento de cómo hacer el diagnóstico y cuándo y cómo tratarle. Nominativamente ha sido llamada de más de 75 formas diferentes y clasificada con dificultad mediante ecocardiografía hace ya más de 40 años. Hoy en día es necesario entender que su comportamiento fenotípico diverso así como las etapas evolutivas de la enfermedad, deben ser abordadas de una forma práctica y eficaz, de tal forma que ello facilite el entendimiento de su comportamiento clínico y su pronóstico, así como de las necesidades terapéuticas en cada caso en particular. Se hace una revisión de los aspectos nominativos de la entidad y proponemos una nueva clasificación que podría facilitar al cardiólogo clínico y quirúrgico un mejor entendimiento de la Miocardiopatía Hipertrófica en sus diversas formas morfológicas y funcionales.

ICD indication in hypertrophic cardiomyopathy: which algorithm to use?

SUMMARY OBJECTIVE: This study aimed to evaluate the agreement in the indication of implantable cardioverter-defibrillators in patients with Hypertrophic cardiomyopathy, as per the 2014 European Society of Cardiology and 2020 American Heart Association recommendations, and evaluate fragmented QRS as a predictor of cardiovascular outcome. METHODS: Retrospective cohort with 81 patients was evaluated between 2019 and 2021. Patients with hypertrophic cardiomyopathy ≥16 years old were included. Exclusion criteria include secondary myocardiopathy and follow-up <1 year. Kappa coefficient was used to determine the agreement. Survival and incidence curves were determined by Kaplan-Meier method. A p<0.05 was considered significant. RESULTS: The fragmented QRS was identified in 44.4% of patients. There were no differences between patients with and without fragmented QRS regarding clinical parameters, echocardiography, fibrosis, and sudden cardiac death risk. During follow-up of 4.8±3.4 years, there was no sudden cardiac death, but 20.6% patients with implantable cardioverter-defibrillator had at least one appropriate shock. Three of the seven appropriate shocks occurred in European Society of Cardiology low- to moderate-risk patients. Three shocks occurred in moderate-risk patients and four in American Heart Association high-risk patients. Overall recommendations agreement was 64% with a kappa of 0.270 (p=0.007). C-statistic showed no differences regarding the incidence of appropriate shock (p=0.644). CONCLUSION: sudden cardiac death risk stratification algorithms present discrepancies in implantable cardioverter-defibrillator indication, both with low accuracy.

Ablação septal com cateteres e radiofrequência guiada pela ecocardiografia para tratamento de pacientes com cardiomiopatia hipertrófica obstrutiva: experiência inicial / Septal ablation with radiofrequency catheters guided by echocardiography for treatment of patients with obstructive hypertrophic cardiomyopathy: initial experience

BACKGROUND: Hypertrophic cardiomyopathy (HCM) can cause obstruction in the left ventricular outflow tract (LVOT), and be responsible for the onset of limiting symptoms, such as tiredness. When such symptoms are refractory to pharmacological treatment, interventionist alternative therapies can be useful, such as septal ablation through the infusion of alcohol in the coronary artery or through myectomy. Recently, the use of a radiofrequency (RF) catheter for endocardial septal ablation guided by electroanatomic mapping has proven to be efficient, despite the high incidence of complete atrioventricular block. An alternative would be the application of RF at the beginning point of the septal gradient guided by the transesophageal echocardiography (TEE). The echocardiography is an imaging method with high accuracy to determine septal anatomy. OBJECTIVE: To assess the long term effect of septal ablation for the relief of ventricular-arterial gradient, using TEE to help place the catheter in the area of larger septal obstruction. Besides, to assess the effects of ablation on the functional class and echocardiographic parameters. METHODS: Twelve asymptomatic patients, with LVOT obstruction, refractory to pharmacological therapy, underwent endocardial septal ablation with 8mm-tip catheters, whose placement was oriented in the region of larger obstruction, assisted by the TEE. Temperature-controlled and staggered RF applications were performed. After each application, the gradient was reassessed and a new application was performed according to the clinical criterion. The effects of RF applications were assessed both for the gradient at rest and for that provoked by the Valsalva maneuver, and considering the gradient. The differences were significant when p-value was lower than or equal to 0.05. RESULTS: It was possible to observe that the mean reduction of the maximum gradients was from 96.8±34.7 mmHg to 62.7±25.4 mmHg three months after the procedure (p=0.0036). After one year, the mean of maximum gradient was 36.1±23.8 mmHg (p=0.0001). The procedure was well tolerated, without records of complete atrioventricular block nor severe complications. CONCLUSION: The TEE-guided septal ablation was efficient and safe, and the results were maintained during the clinical follow-up period. It is a reasonable option for the interventionist treatment of LVOT obstruction in HCM.

FUNDAMENTOS: A cardiomiopatia hipertrófica (CMH) pode causar obstrução da via de saída do ventrículo esquerdo (VSVE) e ser responsável pelo surgimento de sintomas limitantes, como cansaço físico. Quando tais sintomas são refratários ao tratamento farmacológico, os tratamentos alternativos intervencionistas podem ser úteis, como a ablação septal por meio da infusão de álcool na artéria coronária ou por meio da miectomia cirúrgica. Recentemente, o uso de cateter de radiofrequência (RF) para ablação do septo endocárdico guiado por mapeamento eletroanatômico mostrou-se eficaz apesar da elevada incidência de bloqueio atrioventricular total. Uma alternativa seria a aplicação de radiofrequência no ponto de início do gradiente septal guiada pelo ecocardiograma transesofágico (ETE). O ecocardiograma é um método de imagem com elevada acurácia para determinação da anatomia septal. OBJETIVO: Avaliar o efeito em longo prazo da ablação septal para alívio do gradiente ventrículo-arterial, utilizando o ETE para auxiliar no posicionamento do cateter na área de maior obstrução septal. Avaliar também os efeitos da ablação na classe funcional e parâmetros ecocardiográficos. MÉTODOS: Doze pacientes sintomáticos com obstrução da VSVE, refratários à terapia farmacológica, foram submetidos à ablação endocárdica septal com cateteres com ponta de 8 mm, cujo posicionamento foi orientado na região de maior obstrução com auxílio do ETE. Foram realizadas aplicações de radiofrequência (RF) termocontrolada e escalonadas sobre a área alvo. Após cada aplicação, o gradiente era reavaliado e nova aplicação era realizada de acordo com critério clínico. Foram avaliados os efeitos das aplicações de RF tanto para o gradiente em repouso como para o provocado por meio da manobra de Valsalva, e considerado o gradiente. As diferenças foram significativas quando o valor de p foi menor ou igual a 0,05. RESULTADOS: Observou-se que a redução da média dos gradientes máximos obtidos foi de 96,8±34,7 mmHg para 62,7±25,4 mmHg ao final de três meses do procedimento (p=0,0036). Após um ano, a média dos gradientes máximos obtidos foi de 36,1±23,8 mmHg (p=0,0001). O procedimento foi bem tolerado e não houve registro de bloqueio atrioventricular total e nem complicações graves. CONCLUSÃO: A ablação septal guiada pelo ETE foi eficaz e segura, com resultados mantidos durante o período de seguimento clínico. É uma opção razoável para o tratamento intervencionista da obstrução da VSVE em CMH.

Anesthetic Management of A Patient with Hypertrophic Cardiomyopathy Posted For Non朇ardiac Surgery � Case Report

Hypertrophic cardiomyopathy (HOCM) is a complex cardiac disorder of genetic origin. Though the patients may be asymptomatic the stress of surgery and anaesthesia is known to exacerbate the left ventricular outflow tract (LVOT) obstruction leading to catastrophic complications. We hereby report a successful anaesthetic management of a patient with left intertrochantric fracture diagnosed with HOCM. Careful and meticulous strategies to prevent LVOT obstruction led to entire uneventful introperative and perioperative course.

Evaluation of myocardial microcirculation abnormalities in patients with hypertrophic cardiomyopathy by myocardial contrast echocardiography combined with exercise stress test / 中华超声影像学杂志

Objective:To detect the abnormal changes of myocardial blood perfusion in patients with hypertrophic cardiomyopathy (HCM) by myocardial contrast echocardiography(MCE) combined with exercise stress test.Methods:Twenty-seven patients with clinically diagnozed of asymmetric HCM in Fuwai Central China Cardiovascular Hospital from May 2020 to April 2021 were selected as the HCM group, and 29 healthy subjects during the same period were selected as the control group. All patients underwent routine echocardiography, resting and exercise stress MCE. The myocardial perfusion parameters of each segment of interventricular septum in the 2 groups were quantitatively analyzed: the peak plateau intensity (A value), ascending slope of the curve(β value) and value of A×β. According to the end-diastolic myocardial thickness, the interventricular septum of the HCM group was divided into hypertrophic and non-hypertrophic segments, and the myocardial contrast parameters of the interventricular septum of the study group were compared with those of the control group. The myocardial blood flow reserve value of the two groups were calculated, and the correlation of myocardial blood flow reserve value with left ventricular mass index (LVMI) and left ventricular remodeling index (LVRI) were analyzed.Results:No matter at rest or under stress, the A value, β value and A×β value of ventricular septal hypertrophic and non-hypertrophic segments in the hypertrophic cardiomyopathy group were lower than those in the control group, and the differences were statistically significant (all P<0.05). Under stress, the A value, β value and A×β value of interventricular septal hypertrophic segments were lower than those in non-hypertrophic segments in the HCM group, and the differences were statistically significant (all P<0.05). The myocardial blood flow reserve in the HCM group was negatively correlated with LVMI and LVRI( r=-0.899, -0.676; all P<0.001). Conclusions:In patients with HCM under resting and exercise stress, microcirculation disorders were found in both hypertrophic and non-hypertrophic segments of the ventricular wall, and the myocardial blood flow reserve was negatively correlated with LVMI and LVRI.

Automatic detection model of hypertrophic cardiomyopathy based on deep convolutional neural network / 生物医学工程学杂志

The diagnosis of hypertrophic cardiomyopathy (HCM) is of great significance for the early risk classification of sudden cardiac death and the screening of family genetic diseases. This research proposed a HCM automatic detection method based on convolution neural network (CNN) model, using single-lead electrocardiogram (ECG) signal as the research object. Firstly, the R-wave peak locations of single-lead ECG signal were determined, followed by the ECG signal segmentation and resample in units of heart beats, then a CNN model was built to automatically extract the deep features in the ECG signal and perform automatic classification and HCM detection. The experimental data is derived from 108 ECG records extracted from three public databases provided by PhysioNet, the database established in this research consists of 14,459 heartbeats, and each heartbeat contains 128 sampling points. The results revealed that the optimized CNN model could effectively detect HCM, the accuracy, sensitivity and specificity were 95.98%, 98.03% and 95.79% respectively. In this research, the deep learning method was introduced for the analysis of single-lead ECG of HCM patients, which could not only overcome the technical limitations of conventional detection methods based on multi-lead ECG, but also has important application value for assisting doctor in fast and convenient large-scale HCM preliminary screening.