Estudio preliminar de correlación fenotipo-genotipo en miocardiopatías de pacientes derivados a un centro de alta complejidad del conurbano bonaerense / A Preliminary Study of the Phenotype-Genotype Correlation in Cardiomyopathies in Patients Referred to a Tertiary Healthcare Center in the Suburbs of Buenos Aires

RESUMEN Introducción : Las miocardiopatías se definen como un trastorno del miocardio en el que el músculo cardíaco es estructural y funcionalmente anormal, en ausencia de enfermedad arterial coronaria, hipertensión arterial (HTA), enfermedad valvular y enfermedad cardíaca congénita. Estas enfermedades son relativamente frecuentes, y suponen una importante causa de morbimortalidad a nivel global. Aunque el estudio genético se recomienda para el cribado familiar, la falta de datos robustos sobre asociaciones genotipo-fenotipo específicas ha reducido su impacto en el manejo clínico. Objetivos : El objetivo de este estudio es analizar la frecuencia de mutaciones en una población de pacientes con miocardiopatía derivados a un centro de alta complejidad y el análisis de la correlación genotipo-fenotipo en las mutaciones identificadas. Material y métodos: Se estudiaron en forma prospectiva 102 pacientes con sospecha de miocardiopatía hipertrófica (MCH) familiar, de los cuales 70 constituían casos índices, de una cohorte ambispectiva de pacientes con miocardiopatías controladas en un hos pital público de alta complejidad de tercer nivel de atención de la provincia de Buenos Aires, desde enero 2012 al 30 agosto 2022. Resultados : De 102 pacientes 83 fueron considerados afectados. De eelos, 31 eran MCH y 52 fenocopias, sin diferencia en el pronóstico. Se realizó estudio genético en 77 pacientes, de los cuales 57 presentaron mutaciones reconocibles, en el 80% de los casos coincidentes con un Score de Mayo ≥3. Se detectaron 28 variantes de significado incierto. Conclusiones : Se comprobó que realizar estudio molecular guiado por el Score de Mayo permitió obtener un alto grado de probabilidad de detectar mutaciones. Se evidenció la importancia del estudio molecular debido a la existencia de solapamiento fenotípico y genotípico de las miocardiopatías. El conocimiento de la variante genética causal actualmente no afecta el manejo clínico de la mayoría de los pacientes con MCH, pero es de ayuda ante un pequeño grupo de genes que tienen opciones de tratamiento.

ABSTRACT Background : Cardiomyopathies are defined as a disorder of the myocardium in which the heart muscle is structurally and functionally abnormal, in the absence of coronary artery disease, hypertension (HT), valvular heart disease and congenital heart disease. These diseases are relatively common and a major cause of morbidity and mortality worldwide. Although genetic testing is recommended for family screening, lack of solid data on specific genotype-phenotype associations has reduced its impact on clinical management. Objectives : This study aims to analyze the frequency of mutations in a population of patients with cardiomyopathy referred to a tertiary healthcare center and to analyze the genotype-phenotype correlation of the identified mutations. Methods : We prospectively included 102 patients with suspected familial hypertrophic cardiomyopathy (HCM), 70 of which were index cases, from an ambispective cohort of patients with cardiomyopathies treated in a tertiary healthcare public hos pital in the province of Buenos Aires, from January 2012 to August 30, 2022. Results : Of 102 patients, 83 were considered affected. Of these, 31 were HCM and 52 were phenocopies, with no difference in prognosis. A genetic study was carried out in 77 patients, of whom 57 presented recognizable mutations, in 80% of the cases coinciding with a Mayo Score ≥3. Twenty-eight variants of uncertain significance were detected. Conclusions : It was confirmed that molecular testing guided by the Mayo Score provided high probability of detecting mutations. Molecular testing proved to be important due to the phenotypic and genotypic overlap in cardiomyopathies. Understanding the causative genetic variant, nowadays, does not affect the clinical management of most HCM patients, but is helpful in a small group of genes with treatment options.

Cardiomiopatia Hipertrófica - Revisão / Hypertrophic Cardiomyopathy: A Review

Resumo A cardiomiopatia hipertrófica (CMH) é a doença cardíaca de origem genética mais comum, cuja principal característica consiste na hipertrofia ventricular esquerda que acontece na ausência de outras patologias que desencadeiam tal alteração. A CMH pode se apresentar desde formas assintomáticas até manifestações de morte cardíaca súbita e de insuficiência cardíaca refratária. Métodos de imagem contemporâneos de alta resolução e escores clínicos mais acurados vêm sendo utilizados e desenvolvidos no sentido de propiciar uma avaliação prognóstica e funcional mais adequada, bem como possibilitar a estratificação dos casos de maior gravidade. Nesta revisão, serão abordados esses aspectos, entre outros tópicos clássicos inerentes ao estudo dessa doença.

Abstract Hypertrophic cardiomyopathy (HCM) is the most common heart disease with a genetic origin, and its main characteristic is left ventricular hypertrophy that occurs in the absence of other conditions that trigger this change. HCM may present from asymptomatic forms to manifestations of sudden cardiac death and severe heart failure. Contemporary high-resolution imaging methods and more accurate clinical scores have been used and developed to provide a prognostic assessment and adequate functional assessments, as well as to allow for the stratification of clinical severity. These aspects will be addressed in this review, along with other classic topics inherent to the study of this disease.

Discordância entre Diretrizes Internacionais sobre Critérios de Prevenção Primária de Morte Súbita na Cardiomiopatia Hipertrófica / Discrepancy between International Guidelines on the Criteria for Primary Prevention of Sudden Cardiac Death in Hypertrophic Cardiomyopathy

Resumo Fundamento A estratificação de risco para morte súbita (MS) na cardiomiopatia hipertrófica (CMH) baseia-se em algoritmos distintos propostos pela diretriz norte-americana, ACCF/AHA 2011 e europeia, ESC 2014. Objetivo Analisar o modelo ESC 2014 na determinação do risco de MS e indicação de cardiodesfibrilador implantável (CDI) em prevenção primária na CMH por meio de confrontação com a normativa norte-americana. Métodos Foi avaliada uma coorte de pacientes com CMH, calculado o escore ESC HCM-Risk-SCD e analisada a concordância dos critérios de indicação de CDI entre as duas diretrizes pelo coeficiente de Kappa. O nível de significância adotado nas análises estatísticas foi de 5%. Resultados Em 90 pacientes consecutivos, seguidos por 6±3 anos, o escore calculado foi de 3,2±2,5%. Os preditores que mais contribuíram para o cálculo nas faixas de baixo (1,88% [1,42-2,67]), médio (5,17% [4,89-5,70]) e alto risco (7,82% [7,06-9,19]) foram espessura parietal máxima do ventrículo esquerdo (1,60% [1,25-2,02] ; 3,20% [3,18-3,36] ; 4,46% [4,07-5,09]), diâmetro do átrio esquerdo (0,97% [0,83-1,21]; 1,86% [1,67-2,40]; 2,48% [2,21-3,51]) e idade (-0,91% [0,8-1,13]; -1,90% [1,12-2,03]; -2,34% [1,49-2,73]). O modelo europeu reduziu as recomendações de CDI em 32 (36%) pacientes. Entre os 43 (48%) em classe IIa pela ACCF/AHA , 8 (18%) migraram para IIb e 24 (56%) para III. Baixa concordância foi identificada entre as duas sistematizações, Kappa = 0,355, p = 0,0001. Dos 8 (9%) pacientes com MS ou choque apropriado, 4 (50%) atingiram indicação IIa pela ACCF/AHA , mas nenhum pela ESC . Conclusão Baixa concordância foi identificada entre as diretrizes analisadas. O novo modelo reduziu as indicações de CDI, notadamente em classe IIa, mas deixou desprotegida a totalidade de pacientes com MS ou choque apropriado. (Arq Bras Cardiol. 2020; 115(2):197-204)

Abstract Background Risk stratification for sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM) is based on different algorithms proposed by the 2011 ACCF/AHA and 2014 ESC guidelines. Objective To analyze the 2014 ESC model for SCD risk stratification and primary prevention ICD (implantable cardioverter defibrillator) in HCM in comparison to the North American guideline. Methods An HCM cohort was evaluated and the ESC HCM-Risk SCD score was calculated. Agreement of ICD recommendations criteria between the two guidelines was analyzed with Kappa coefficient. P<0.05 was adopted for the statistical analysis. Results In 90 consecutive patients followed for 6±3 years, the mean calculated ESC risk score was 3.2±2.5%. The risk predictors that have mainly contributed to the score calculation in the low (1.88% [1.42-2.67]), intermediate (5.17% [4.89-5.70]) and high-risk (7.82% [7.06-9.19]) categories were: maximal left ventricular wall thickness (1.60% [1.25-2.02]; 3.20% [3.18-3.36]; 4.46% [4.07-5.09]), left atrial diameter (0.97% [0.83-1.21]; 1.86% [1.67-2.40]; 2.48% [2.21-3.51]) and age (-0.91% [0.8-1.13]; -1.90% [1.12-2.03]; -2.34% [1.49-2.73]). The European model decreased the ICD recommendations in 32 (36%) patients. Among the 43 (48%) individuals with class IIa recommendation under the 2011 ACCF/AHA guideline, 8 (18%) were downgraded to class IIb and 24 (56%) to class III. Low agreement was found between the two systems: Kappa=0.355 and p=0.0001. In 8 (9%) patients with SCD or appropriate shock, 4 (50%) met class IIa indication with the 2011 ACCF/AHA guideline, but none achieved this class of recommendation with the 2014 ESC model. Conclusion Low agreement was found between the two strategies. The novel ESC model decreased the ICD recommendations, especially in those with class IIa recommendation, but left unprotected all patients with SCD or appropriate shock. (Arq Bras Cardiol. 2020; 115(2):197-204)