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Hypertrophic cardiomyopathy has a different presentation spectrum, including left ventricular outflow tract obstruction. The most common phenotype is the asymmetric septal variant, with the mid-apical variant being rare. On the other hand, there are specific mutations associated with hypertrophic cardiomyopathy, with the Filamin C variant being an unusual condition in these patients. Therefore, we present the case of a 23-year-old male patient with a diagnosis of hypertrophic cardiomyopathy in whom a Filamin C variant was documented. Given the inadequate response and persistence of symptoms to medical management, a myectomy procedure was performed with a transapical approach, with subsequent improvement in clinical symptoms and outflow tract obstruction. This case illustrates a rare variant with a surgical approach different from the conventional transaortic approach, with marked improvement in symptoms.

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Hypertrophic cardiomyopathy (HCM) with left ventricular outflow tract obstruction that doesn't improve with pharmacological management often requires septal myectomy. However, there are few centers with experience in the practice of this procedure in our country. We describe the clinical and echocardiographic characteristics and postoperative outcomes of patients with HCM indicated for septal myectomy at a reference center in Colombia. MATERIALS AND METHODS: Retrospective cohort study. Patients undergoing septal myectomy between 2010 and 2023 were included. Data were collected before and two years after surgery. RESULTS: 18 patients were included. The mean age was 50 years. The predominant functional class was NYHA II/III (94 %). Asymmetric septal variant (83.3 %) was the most frequent as well as obstructive phenotype (88.8 %). After myectomy, 70.5 % improved to NYHA I and 62.4 % had no significant gradient (<30 mmHg), and the most of patient improved SAM. One patient died post-procedure, anymore complications were presented. DISCUSSION/CONCLUSIONS: Septal myectomy is a safe procedure, with clinical and echocardiographic improvement, with low complication rates.

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INTRODUCTION: The aim of our study is to compare the early and mid-term outcomes of patients with hypertrophic obstructive cardiomyopathy who underwent classic and modified Morrow septal myectomy. METHODS: Between 2014 and 2019, 48 patients (24 males; mean age 49.27±16.41 years) who underwent septal myectomy were evaluated. The patients were divided into two groups - those who underwent classic septal myectomy (n=28) and those who underwent modified septal myectomy (n=20). RESULTS: Mitral valve intervention was higher in the classic Morrow group than in the modified Morrow group, but there was no significant difference (P=0.42). Mortality was found to be lower in the modified Morrow group than in the classic Morrow group (P=0.01). In both groups, the mean immediate postoperative gradient was significantly higher than the mean of the 3rd and 12th postoperative months. The preoperative and postoperative gradient difference of the modified Morrow group was significantly higher than of the classic Morrow group (P<0.001). CONCLUSION: Classic Morrow and modified Morrow procedures are effective methods for reducing left ventricular outflow tract obstruction. The modified Morrow procedure was found to be superior to the classic Morrow procedure in terms of reducing the incidence of mitral valve intervention with the reduction of the left ventricular outflow tract gradient.

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ABSTRACT Introduction: The aim of our study is to compare the early and mid-term outcomes of patients with hypertrophic obstructive cardiomyopathy who underwent classic and modified Morrow septal myectomy. Methods: Between 2014 and 2019, 48 patients (24 males; mean age 49.27±16.41 years) who underwent septal myectomy were evaluated. The patients were divided into two groups - those who underwent classic septal myectomy (n=28) and those who underwent modified septal myectomy (n=20). Results: Mitral valve intervention was higher in the classic Morrow group than in the modified Morrow group, but there was no significant difference (P=0.42). Mortality was found to be lower in the modified Morrow group than in the classic Morrow group (P=0.01). In both groups, the mean immediate postoperative gradient was significantly higher than the mean of the 3rd and 12th postoperative months. The preoperative and postoperative gradient difference of the modified Morrow group was significantly higher than of the classic Morrow group (P<0.001). Conclusion: Classic Morrow and modified Morrow procedures are effective methods for reducing left ventricular outflow tract obstruction. The modified Morrow procedure was found to be superior to the classic Morrow procedure in terms of reducing the incidence of mitral valve intervention with the reduction of the left ventricular outflow tract gradient.

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La miocardiopatía hipertrófica es cada vez más diagnosticada. Es una condición genética que genera hipertrofia miocárdica, fibrosis, isquemia y apoptosis con obstrucción del tracto de salida del ventrículo izquierdo. Puede generar síncope, falla cardíaca y muerte súbita. El tratamiento es farmacológico y se requiere cirugía si hay refractariedad. Se presenta un caso de miocardiopatía hipertrófica asociada a variante genética patogénica en un paciente no respondedor a manejo médico óptimo. La importancia de este artículo radica en lo determinante que es la genética para el abordaje diagnóstico y el establecimiento del origen y pronóstico de esta enfermedad.

Hypertrophic cardiomyopathy is increasingly diagnosed. It is a genetic condition that leads to myocardial hypertrophy, fibrosis, ischemia, and apoptosis with obstruction of the left ventricular outflow tract. It can result in syncope, heart failure, and sudden death. Treatment is pharmacological, and surgery is required in cases of refractoriness. A case of hypertrophic cardiomyopathy associated with a pathogenic genetic variant is presented in a patient unresponsive to optimal medical management. The importance of this article lies in how crucial genetics is for the proper diagnostic approach and the establishment of the origin and prognosis of this disease.

A miocardiopatia hipertrófica está sendo diagnosticada cada vez mais. É uma condição genética que leva à hipertrofia miocárdica, fibrose, isquemia e apoptose com obstrução do trato de saída do ventrículo esquerdo. Pode resultar em síncope, insuficiência cardíaca e morte súbita. O tratamento é farmacológico e a cirurgia é necessária em casos de refratariedade. Apresenta-se um caso de miocardiopatia hipertrófica associada a uma variante genética patogênica em um paciente não responsivo ao manejo médico ótimo. A importância deste artigo reside na determinante genética para a abordagem diagnóstica adequada e para o estabelecimento da origem e prognóstico desta doença.

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BACKGROUND: Microvasculature dysfunction is a common finding in pathologic remodeling of the heart and is thought to play an important role in the pathogenesis of hypertrophic cardiomyopathy (HCM), a disease caused by sarcomere gene mutations. We hypothesized that microvascular dysfunction in HCM was secondary to abnormal microvascular growth and could occur independent of ventricular hypertrophy. METHODS: We used multimodality imaging methods to track the temporality of microvascular dysfunction in HCM mouse models harboring mutations in the sarcomere genes Mybpc3 (cardiac myosin binding protein C3) or Myh6 (myosin heavy chain 6). We performed complementary molecular methods to assess protein quantity, interactions, and post-translational modifications to identify mechanisms regulating this response. We manipulated select molecular pathways in vivo using both genetic and pharmacological methods to validate these mechanisms. RESULTS: We found that microvascular dysfunction in our HCM models occurred secondary to reduced myocardial capillary growth during the early postnatal time period and could occur before the onset of myocardial hypertrophy. We discovered that the E3 ubiquitin protein ligase MDM2 (murine double minute 2) dynamically regulates the protein stability of both HIF1α (hypoxia-inducible factor 1 alpha) and HIF2α (hypoxia-inducible factor 2 alpha)/EPAS1 (endothelial PAS domain protein 1) through canonical and noncanonical mechanisms. The resulting HIF imbalance leads to reduced proangiogenic gene expression during a key period of myocardial capillary growth. Reducing MDM2 protein levels by genetic or pharmacological methods normalized HIF protein levels and prevented the development of microvascular dysfunction in both HCM models. CONCLUSIONS: Our results show that sarcomere mutations induce cardiomyocyte MDM2 signaling during the earliest stages of disease, and this leads to long-term changes in the myocardial microenvironment.

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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.

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Resumo Fundamento: A morte súbita cardíaca (MSC), decorrente de arritmias ventriculares, é a principal complicação da cardiomiopatia hipertrófica (CMH). A microalternância da onda T (MAOT) está associada à ocorrência de arritmias ventriculares em diversas cardiopatias, mas seu papel na CMH permanece incerto. Objetivo: Avaliar associação da MAOT com a ocorrência de MSC ou arritmias ventriculares malignas em pacientes com CMH. Método: Pacientes com diagnóstico de CMH e classe funcional I-II (NYHA) foram selecionados de forma consecutiva. No início do seguimento os participantes realizaram a avaliação da MAOT pela metodologia da média móvel modificada no teste de esforço. Os resultados foram classificados em alterado ou normal. O desfecho foi composto por MSC, fibrilação ventricular, taquicardia ventricular sustentada (TVS) e terapia apropriada do cardioversor desfibrilador implantável (CDI). O nível de significância estatística foi de 5%. Resultados: Um total de 132 pacientes (idade média de 39,5±12,6 anos) foram incluídos, com tempo de seguimento médio de 9,5 anos. A MAOT foi alterada em 74 (56%) participantes e normal em 58 (44%). Durante o seguimento, nove (6,8%) desfechos ocorreram, com prevalência de 1,0%/ano, sendo seis casos de MSC, dois choques apropriados do CDI e um episódio de TVS. MAOT alterada foi associada à taquicardia ventricular não sustentada no Holter (p=0,016), espessura septal≥30 mm (p<0,001) e resposta inadequada da pressão arterial ao esforço (p=0,046). Cinco pacientes (7%) e quatro pacientes (7%) com MAOT alterada e normal, respectivamente, apresentaram desfecho primário [OR=0,85(IC95%: 0,21-3,35, p=0,83)]. Curvas de eventos de Kaplan-Meir não apresentaram diferenças entre MAOT normal e alterada. Conclusão: A MAOT alterada não foi associada à ocorrência de MSC ou arritmias ventriculares potencialmente fatais em pacientes com CMH, e a baixa taxa desses eventos em um seguimento em longo prazo sugere o bom prognóstico dessa cardiopatia.

Abstract Background: Sudden cardiac death (SCD) resulting from ventricular arrhythmia is the main complication of hypertrophic cardiomyopathy (HCM). Microvolt T-wave alternans (MTWA) is associated with the occurrence of ventricular arrhythmias in several heart diseases, but its role in HCM remains uncertain. Objective: To evaluate the association of MTWA with the occurrence of SCD or potentially fatal ventricular arrhythmias in HCM patients in a long-term follow-up. Methods: Patients diagnosed with HCM and NYHA functional class I-II were consecutively selected. At the beginning of the follow-up, the participants performed the MTWA evaluation using the modified moving average during the stress test. The results were classified as altered or normal. The composite endpoint of SCD, ventricular fibrillation, sustained ventricular tachycardia (SVT) or appropriate implantable cardiac defibrillation (ICD) therapy was assessed. The level of significance was set at 5%. Results: A total of 132 patients (mean age of 39.5 ± 12.6 years) were recruited and followed for a mean of 9.5 years. The MTWA test was altered in 74 (56%) participants and normal in 58 (44%). Nine events (6.8%) occurred during the follow-up, with a prevalence of 1.0%/year - six SCDs, two appropriate ICD shocks and one episode of (SVT). Altered MTWA was associated with non-sustained ventricular tachycardia on Holter (p = 0.016), septal thickness ≥30 mm (p < 0.001) and inadequate blood pressure response to effort (p = 0.046). Five patients with altered MTWA (7%) and four patients with normal MTWA (7%) had the primary outcome [OR = 0.85 (95% CI: 0.21 - 3.35, p=0.83)]. Kaplan-Meir event curves showed no differences between normal and altered MTWA. Conclusion: Altered MTWA was not associated with the occurrence of SCD or potentially fatal ventricular arrhythmias in HCM patients, and the low rate of these events during long-term follow-up suggests the good prognosis of this heart disease.

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Resumo Fundamento A síndrome do PRKAG2 é uma doença hereditária autossômica dominante rara, de início precoce. Objetivamos descrever os achados ecocardiográficos do ventrículo direito (VD) usando modalidades bi e tridimensionais (2D e 3D), incluindo índices de deformação miocárdica nesta cardiomiopatia. Também objetivamos demonstrar se esta técnica poderia identificar alterações na função do VD que pudessem distinguir quaisquer achados particulares. Métodos Trinta pacientes com síndrome do PRKAG2 (R302Q e H401Q) geneticamente comprovada, 16 (53,3%) do sexo masculino, com idade média de 39,1 ± 15,4 anos, foram submetidos a exame ecocardiográfico completo. A visão de 4 câmaras com foco no VD foi adquirida para medições 2D e 3D. Os testes t de Student ou Wilcoxon-Mann-Whitney foram usados para comparar as variáveis numéricas entre 2 grupos, e p < 0,05 foi considerado significativo. Resultados Doze pacientes (40%) tiveram marca-passo implantado por 12,4 ± 9,9 anos. A espessura diastólica média da parede livre do VD foi de 7,9 ± 2,9 mm. O strain longitudinal de 4 câmaras do VD (SL4VD), incluindo a parede livre e o septo interventricular, foi de -17,3% ± 6,7%, e o strain longitudinal da parede livre do VD (SLPLVD) foi de −19,1% ± 8,5%. A razão apical do SLPLVD mediu 0,63 ± 0,15. A fração de ejeção (FE) 3D média do VD foi de 42,6% ± 10,9% e abaixo dos limites normais em 56,7% dos pacientes. Correlação positiva ocorreu entre FE 3D do VD, SL4VD e SLPLVD, principalmente para pacientes sem marca-passo (p = 0,006). Conclusão O envolvimento do VD em PRKAG2 é frequente e ocorre em diferentes graus. A ecocardiografia é uma ferramenta valiosa na detecção de anormalidades miocárdicas do VD nesta condição. O uso de SL4VD 2D, SLPLVD e FE 3D oferecem indicadores confiáveis de disfunção sistólica do VD nesta cardiomiopatia rara e desafiadora.

Abstract Background PRKAG2 syndrome is a rare, early-onset autosomal dominant inherited disease. We aimed to describe the right ventricle (RV) echocardiographic findings using two and three-dimensional (2D and 3D) modalities including myocardial deformation indices in this cardiomyopathy. We also aimed to demonstrate whether this technique could identify changes in RV function that could distinguish any particular findings. Methods Thirty patients with genetically proven PRKAG2 (R302Q and H401Q), 16 (53.3%) males, mean age 39.1 ± 15.4 years, underwent complete echocardiography examination. RV-focused, 4-chamber view was acquired for 2D and 3D measurements. Student's t or Wilcoxon-Mann-Whitney tests were used to compare numerical variables between 2 groups, and p < 0.05 was considered significant. Results Twelve patients (40%) had a pacemaker implanted for 12.4 ± 9.9 years. RV free wall mean diastolic thickness was 7.9 ± 2.9 mm. RV 4-chamber longitudinal strain (RV4LS), including the free wall and interventricular septum, was -17.3% ± 6.7%, and RV free wall longitudinal strain (RVFWLS) was −19.1% ± 8.5%. The RVFWLS apical ratio measured 0.63 ± 0.15. Mean RV 3D ejection fraction (EF) was 42.6% ± 10.9% and below normal limits in 56.7% of patients. Positive correlation occurred between RV 3DEF, RV4LS, and RVFWLS, especially for patients without a pacemaker (p = 0.006). Conclusion RV involvement in PRKAG2 syndrome is frequent, occurring in different degrees. Echocardiography is a valuable tool in detecting RV myocardial abnormalities in this condition. The use of 2D RV4LS, RVFWLS, and 3DEF offers reliable indicators of RV systolic dysfunction in this rare, challenging cardiomyopathy.

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Resumo Fundamento A síndrome do PRKAG2 é uma rara doença genética autossômico dominante, fenocópia da miocardiopatia hipertrófica, caracterizada pelo acúmulo intracelular de glicogênio. Manifestações clínicas incluem pré-excitação ventricular, hipertrofia ventricular, distúrbio de condução cardíaca e arritmias atriais. Objetivo Comparar características clínicas e eletrofisiológicas observadas em pacientes com flutter atrial, com e sem síndrome do PRKAG2. Métodos Estudo observacional, comparativo de pacientes com flutter atrial: grupo A, cinco pacientes de família com síndrome do PRKAG2; e grupo B, 25 pacientes sem fenótipo da síndrome. O nível de significância foi de 5%. Resultados Todos os pacientes do grupo A apresentaram pré-excitação ventricular e bloqueio de ramo direito; quatro tinham marca-passo (80%). Pacientes do grupo A tinham menor idade (39±5,4 vs. 58,6±17,6 anos, p=0,021), e maior espessura de septo interventricular (mediana=18 vs. 10 mm; p<0,001) e parede posterior (mediana=14 vs. 10 mm; p=0,001). Quatro do grupo A foram submetidos a estudo eletrofisiológico, sendo observada via acessória fascículo-ventricular; em três foi realizada ablação do flutter atrial. Todos os do grupo B foram submetidos à ablação do flutter atrial, sem evidência de via acessória. Observado maior prevalência no grupo B de hipertensão arterial, diabetes mellitus, doença coronariana e apneia do sono, sem diferença estatisticamente significante. Conclusão Portadores da síndrome do PRKAG2 apresentaram flutter atrial em idade mais precoce, e menos comorbidades, quando comparados a pacientes com flutter atrial sem fenótipo da mutação. Importante suspeitar de miocardiopatia geneticamente determinada, como síndrome do PRKAG2, em jovens com flutter atrial, especialmente na presença de pré-excitação ventricular e hipertrofia ventricular familiar.

Abstract Background PRKAG2 syndrome is a rare autosomal dominant disease, a phenocopy of hypertrophic cardiomyopathy characterized by intracellular glycogen accumulation. Clinical manifestations include ventricular preexcitation, cardiac conduction disorder, ventricular hypertrophy, and atrial arrhythmias. Objective To compare the clinical and electrophysiological characteristics observed in patients with atrial flutter, with and without PRKAG2 syndrome. Methods An observational study comparing patients with atrial flutter: group A consisted of five patients with PRKAG2 syndrome from a family, and group B consisted of 25 patients without phenotype of PRKAG2 syndrome. The level of significance was 5%. Results All patients in group A had ventricular preexcitation and right branch block, and four had pacemakers (80%). Patients in group A were younger (39±5.4 vs 58.6±17.6 years, p=0.021), had greater interventricular septum (median=18 vs 10 mm; p<0.001) and posterior wall thickness (median=14 vs 10 mm; p=0.001). In group A, four patients were submitted to an electrophysiological study, showing a fasciculoventricular pathway, and atrial flutter ablation was performed in tree. All patients in group B were submitted to ablation of atrial flutter, with no evidence of accessory pathway. Group B had a higher prevalence of hypertension, diabetes mellitus, coronary artery disease and sleep apnea, with no statistically significant difference. Conclusion Patients with PRKAG2 syndrome presented atrial flutter at an earlier age and had fewer comorbidities when compared to patients with atrial flutter without mutation phenotype. The occurrence of atrial flutter in young individuals, especially in the presence of ventricular preexcitation and familial ventricular hypertrophy, should raise the suspicion of PRKAG2 syndrome.

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RESUMEN Introducción: El T1 mapping es una técnica que permite mejorar la caracterización tisular por resonancia magnética cardíaca (RMC), y posee creciente evidencia a su favor como herramienta de diagnóstico precoz y estratificación. Presentamos los resultados de la cuantificación del T1 nativo miocárdico en individuos sanos, estudiados en un campo de 3.0 T, a fin de proveer valores de referencia para el medio local. Material y métodos: Se incluyeron 124 individuos consecutivos derivados a nuestro centro para realización de RMC, cuyos estudios resultaron normales. Se midió el T1 mapping en un eje corto medioventricular. Se analizaron los resultados según edad y sexo. Se incluyeron también 27 pacientes con diagnóstico de miocardiopatía hipertrófica, 11 con diagnóstico de miocardiopatía dilatada y 8 con amiloidosis cardíaca. Resultados: Se analizaron 124 estudios. La media global de T1 mapping fue de 1220,7 ± 21,2 mseg. Redondeando a valores enteros, se consideró 1178-1263 mseg como "rango de normalidad" (p5-p95). Se observó un tiempo T1 ligeramente superior en mujeres. No hubo diferencias con respecto a la edad. Se observó una excelente reproducibilidad, evaluada por el coeficiente de correlación intraclase (0,97) y el método de Bland-Altman. Los valores de T1 mapping fueron significativamente superiores en los grupos de individuos portadores de miocardiopatía. Conclusiones: Reportamos valores normales de T1 mapping nativo en una población adulta local. Los mismos son levemente mayores en mujeres, diferencia que no impresiona relevante desde el punto de vista clínico. Al comparar con individuos portadores de miocardiopatía hipertrófica, dilatada o con amiloidosis cardíaca, se obtuvo una muy buena discriminación. La variabilidad interobservador fue muy baja.

ABSTRACT Background: T1mapping is a technique that improves tissue characterization by cardiovascular magnetic resonance (CMR), and there is growing evidence favoring its use as a tool for early diagnosis and stratification. We present the results of native myocardial T1 quantification in a 3.0 T field in healthy individuals, in order to provide local reference values. Methods: A total of 124 consecutive adults with normal studies, referred to our center for CMR, were included in the study. T1 relaxation time was measured in a midventricular short axis slice, analyzing age and sex dependance. For comparison, 27 patients with hypertrophic cardiomyopathy, 11 with dilated cardiomyopathy and 8 with cardiac amyloidosis were also included. Results: Mean global T1mapping of the 124 studies analyzed was 1220.7 ±21.2 msec, and rounding to unity, 1178-1263 msec (p5-p95) was considered as "normal range". A slightly longer T1 time was observed in women and no differences were found with respect to age. Excellent reproducibility was obtained, evaluated by intraclass correlation coefficient (0.97) and BlandAltman plot. T1 mapping values were significantly higher in both groups of individuals with cardiomyopathy. Conclusions: We report normal values of native T1 mapping in a local healthy adult population. Times were slightly higher in women, a difference that was not considered clinically relevant. When comparing with individuals with hypertrophic or dilated cardiomyopathy, a very good discrimination was obtained between the 3 populations. The interobserver variability was very low.

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Resumo Fundamento A cardiomiopatia hipertrófica (CMH) e a hipertrofia ventricular esquerda (HVE) secundária à hipertensão arterial sistêmica (HAS) podem estar associadas a anormalidades funcionais do átrio esquerdo (AE). Objetivos Caracterizar a mecânica do AE na CMH e na HAS e avaliar qualquer correlação com a extensão da fibrose ventricular esquerda medida por ressonância magnética cardíaca (RMC) em pacientes com CMH. Métodos A função longitudinal do AE derivada do ecocardiograma bidimensional com speckle tracking foi adquirida a partir de cortes apicais de 60 pacientes com CMH e 34 indivíduos controles, pareados por idade. Pacientes com CMH também foram submetidos à RMC, com medida da extensão do realce tardio por gadolínio. A associação com parâmetros de strain do AE foi analisada. Valores p < 0,05 foram definidos como estatisticamente significativos. Resultados A média da fração de ejeção do ventrículo esquerdo não foi diferente entre os grupos. A razão E/e' estava comprometida no grupo CMH e preservada no grupo controle. A mecânica do AE estava significativamente reduzida na CMH em comparação aos pacientes com HAS. O strain rate do AE nas fases de reservatório (SRrAE) e na fase contrátil (SRctAE) foram os melhores parâmetros de discriminação de CMH com uma área sob a curva (AUC) de 0,8, seguido do strain do AE na fase de reservatório (SrAE) (AUC 0,76). O SRrAE e o SRctAE apresentaram elevada especificidade (89% e 91%, respectivamente), e o SrAE apresentou sensibilidade de 80%. Um decréscimo de 2,79% no strain rate do AE na fase de condução (SRcdAE) foi preditor de um aumento de 1 cm na extensão do RT pelo gadolínio (r2=0,42, β 2,79, p=0,027). Conclusões O SRrAE e o SRctAE foram os melhores fatores de discriminação de HVE secundária à CMH. O SRcdAE foi preditor do grau de fibrose ventricular esquerda avaliada por RMC. Esses achados sugerem que a mecânica do AE pode ser um potencial preditor de gravidade de doença na CMH.

Abstract Background Hypertrophic cardiomyopathy (HCM) and left ventricular hypertrophy (LVH) secondary to systemic hypertension (HTN) may be associated with left atrial (LA) functional abnormalities. Objectives We aimed to characterize LA mechanics in HCM and HTN and determine any correlation with the extent of left ventricular (LV) fibrosis measured by cardiac magnetic resonance (CMR) in HCM patients. Methods Two-dimensional speckle tracking-derived longitudinal LA function was acquired from apical views in 60 HCM patients, 60 HTN patients, and 34 age-matched controls. HCM patients also underwent CMR, with measurement of late gadolinium enhancement (LGE) extension. Association with LA strain parameters was analyzed. Statistical significance was set at p<0.05. Results Mean LV ejection fraction was not different between the groups. The E/e' ratio was impaired in the HCM group and preserved in the control group. LA mechanics was significantly reduced in HCM, compared to the HTN group. LA strain rate in reservoir (LASRr) and in contractile (LASRct) phases were the best discriminators of HCM, with an area under the curve (AUC) of 0.8, followed by LA strain in reservoir phase (LASr) (AUC 0.76). LASRr and LASR-ct had high specificity (89% and 91%, respectively) and LASr had sensitivity of 80%. A decrease in 2.79% of LA strain rate in conduit phase (LASRcd) predicted an increase of 1cm in LGE extension (r2=0.42, β 2.79, p=0.027). Conclusions LASRr and LASRct were the best discriminators for LVH secondary to HCM. LASRcd predicted the degree of LV fibrosis assessed by CMR. These findings suggest that LA mechanics is a potential predictor of disease severity in HCM.

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A cardiomiopatia hipertrófica é a cardiopatia genética mais frequente na população geral e é caracterizada por uma hipertrofia ventricular esquerda assimétrica. Entretanto, as alterações fenotípicas desta cardiomiopatia vão muito além da hipertrofia ventricular, e incluem alterações do aparato valvar mitral, dos músculos papilares e do ventrículo direito. Devido à dificuldade no diagnóstico diferencial entre as múltiplas causas de hipertrofia, a ressonância magnética cardíaca vem cumprindo um papel fundamental na avaliação diagnóstica e prognóstica desta cardiomiopatia. A cineressonância magnética na definição da localização e extensão da hipertrofia, o realce tardio, na detecção das áreas de fibrose miocárdica e técnicas mais recentes como o Mapa de T1 que avalia a fibrose intersticial e o volume extracelular; e finalmente o Tissue Tracking na análise da deformação miocárdica.(AU)

Hypertrophic cardiomyopathy, the most common genetic cardiopathy in the general population, is characterized by asymmetric left ventricular hypertrophy. However, the phenotypic changes in this cardiomyopathy extend beyond ventricular hypertrophy and include changes in the mitral valve apparatus, papillary muscles, and right ventricle. Due to the difficult differential diagnosis among multiple causes of hypertrophy, cardiac magnetic resonance has played a fundamental role in its diagnostic and prognostic evaluation; magnetic cine-resonance in defining the location and extent of hypertrophy; late enhancement, in the detection of areas of myocardial fibrosis; more recent techniques such as T1 mapping that assesses interstitial fibrosis and extracellular volume; and finally tissue tracking in the analysis of myocardial deformation. (AU)

Assuntos

RESUMO

Resumen La cardiomiopatía hipertrófica es una entidad de origen genético que se caracteriza por hipertrofia ventricular izquierda en ausencia de otras enfermedades como etiología. Los pacientes suelen ser asintomáticos; sin embargo, el espectro de presentación es amplio pudiéndose encontrar falla cardiaca, obstrucción del tracto de salida, arritmias, muerte súbita y la etapa final o ''burnout''. La valoración morfológica inicial se realiza con ecocardiograma transtorácico, aunque la resonancia magnética cardiaca es el estudio de elección para confirmar el diagnóstico. Presentamos el caso de una mujer de 43 años con antecedente de cardiomiopatía hipertrófica quien había sido intervenida previamente e ingresó al servicio de urgencias de forma descompensada, documentándose progresión a fase "burnout" y su manejo subsecuente. Si bien este fenotipo no es común tiene importantes implicaciones pronósticas y en la calidad de vida. Por lo anterior, un diagnóstico y tratamiento oportuno pueden impactar favorablemente.

Abstract Hypertrophic cardiomyopathy is a genetic entity characterized by left ventricular hypertrophy in the absence of other diseases as etiology. Patients are usually asymptomatic; however, the spectrum of presentation is wide and may include heart failure, outflow tract obstruction, arrhythmias, sudden death and the final stage also known as ''burnout phase''. The initial morphological assessment is performed with transthoracic echocardiography; however, cardiac magnetic resonance imaging is the gold standard to confirm the diagnosis. We present the case of a 43-year-old woman with a history of previously operated hypertrophic cardiomyopathy who was admitted to the emergency department decompensated, documenting progression to the "burnout" phase and her management. Although this phenotype is not common, it has prognostic and quality of life implications. Therefore, timely diagnosis and treatment can have an impact on these variables.