Guidelines on the Diagnosis and Treatment of Hypertrophic Cardiomyopathy ­ 2024 / Diretriz sobre Diagnóstico e Tratamento da Cardiomiopatia Hipertrófica ­ 2024

Hypertrophic cardiomyopathy (HCM) is a form of genetically caused heart muscle disease, characterized by the thickening of the ventricular walls. Diagnosis requires detection through imaging methods (Echocardiogram or Cardiac Magnetic Resonance) showing any segment of the left ventricular wall with a thickness > 15 mm, without any other probable cause. Genetic analysis allows the identification of mutations in genes encoding different structures of the sarcomere responsible for the development of HCM in about 60% of cases, enabling screening of family members and genetic counseling, as an important part of patient and family management. Several concepts about HCM have recently been reviewed, including its prevalence of 1 in 250 individuals, hence not a rare but rather underdiagnosed disease. The vast majority of patients are asymptomatic. In symptomatic cases, obstruction of the left ventricular outflow tract (LVOT) is the primary disorder responsible for symptoms, and its presence should be investigated in all cases. In those where resting echocardiogram or Valsalva maneuver does not detect significant intraventricular gradient (> 30 mmHg), they should undergo stress echocardiography to detect LVOT obstruction. Patients with limiting symptoms and severe LVOT obstruction, refractory to beta-blockers and verapamil, should receive septal reduction therapies or use new drugs inhibiting cardiac myosin. Finally, appropriately identified patients at increased risk of sudden death may receive prophylactic measure with implantable cardioverter-defibrillator (ICD) implantation.

La miocardiopatía hipertrófica (MCH) es una forma de enfermedad cardíaca de origen genético, caracterizada por el engrosamiento de las paredes ventriculares. El diagnóstico requiere la detección mediante métodos de imagen (Ecocardiograma o Resonancia Magnética Cardíaca) que muestren algún segmento de la pared ventricular izquierda con un grosor > 15 mm, sin otra causa probable. El análisis genético permite identificar mutaciones en genes que codifican diferentes estructuras del sarcómero responsables del desarrollo de la MCH en aproximadamente el 60% de los casos, lo que permite el tamizaje de familiares y el asesoramiento genético, como parte importante del manejo de pacientes y familiares. Varios conceptos sobre la MCH han sido revisados recientemente, incluida su prevalencia de 1 entre 250 individuos, por lo tanto, no es una enfermedad rara, sino subdiagnosticada. La gran mayoría de los pacientes son asintomáticos. En los casos sintomáticos, la obstrucción del tracto de salida ventricular izquierdo (TSVI) es el trastorno principal responsable de los síntomas, y su presencia debe investigarse en todos los casos. En aquellos en los que el ecocardiograma en reposo o la maniobra de Valsalva no detecta un gradiente intraventricular significativo (> 30 mmHg), deben someterse a ecocardiografía de esfuerzo para detectar la obstrucción del TSVI. Los pacientes con síntomas limitantes y obstrucción grave del TSVI, refractarios al uso de betabloqueantes y verapamilo, deben recibir terapias de reducción septal o usar nuevos medicamentos inhibidores de la miosina cardíaca. Finalmente, los pacientes adecuadamente identificados con un riesgo aumentado de muerte súbita pueden recibir medidas profilácticas con el implante de un cardioversor-desfibrilador implantable (CDI).

A cardiomiopatia hipertrófica (CMH) é uma forma de doença do músculo cardíaco de causa genética, caracterizada pela hipertrofia das paredes ventriculares. O diagnóstico requer detecção por métodos de imagem (Ecocardiograma ou Ressonância Magnética Cardíaca) de qualquer segmento da parede do ventrículo esquerdo com espessura > 15 mm, sem outra causa provável. A análise genética permite identificar mutações de genes codificantes de diferentes estruturas do sarcômero responsáveis pelo desenvolvimento da CMH em cerca de 60% dos casos, permitindo o rastreio de familiares e aconselhamento genético, como parte importante do manejo dos pacientes e familiares. Vários conceitos sobre a CMH foram recentemente revistos, incluindo sua prevalência de 1 em 250 indivíduos, não sendo, portanto, uma doença rara, mas subdiagnosticada. A vasta maioria dos pacientes é assintomática. Naqueles sintomáticos, a obstrução do trato de saída do ventrículo esquerdo (OTSVE) é o principal distúrbio responsável pelos sintomas, devendo-se investigar a sua presença em todos os casos. Naqueles em que o ecocardiograma em repouso ou com Manobra de Valsalva não detecta gradiente intraventricular significativo (> 30 mmHg), devem ser submetidos à ecocardiografia com esforço físico para detecção da OTSVE.   Pacientes com sintomas limitantes e grave OTSVE, refratários ao uso de betabloqueadores e verapamil, devem receber terapias de redução septal ou uso de novas drogas inibidoras da miosina cardíaca. Por fim, os pacientes adequadamente identificados com risco aumentado de morta súbita podem receber medida profilática com implante de cardiodesfibrilador implantável (CDI).

Electrovectorcardiographic study of left ventricular aneurysm in ischemic heart disease.

The aim was to characterize the electrovectorcardiographic pattern of ventricular aneurysms in ischemic cardiopathy by analyzing the cardiac ventricular repolarization. The medical records of 2,670 individuals were analyzed in this cross-sectional study. A test phase included 33 patients who underwent transthoracic echocardiogram with ultrasonic enhancing agent, electrocardiogram, and vectorcardiogram (aneurysm group - n = 22, and akinesia group - n = 11). In the validation phase, cardiac magnetic resonance imaging established the left ventricle segmental contractility in 16 patients who underwent electrocardiographic and vectorcardiographic tests (aneurysm group, n = 8, and akinesia group, n = 8). The variables studied were the presence of the T-wave plus-minus pattern and the T-wave loop anterior-posterior pattern in V2-V4. The diagnostic indices used were sensitivity, specificity, and predictive values, with their respective 95% confidence intervals. During the test and validation phases, the analysis of the presence of the T-wave plus-minus pattern identified the aneurysm group with a sensitivity of 91% vs. 87% and specificity of 91% vs. 87% (p < 0.0001 vs. p = 0.01), respectively. Meanwhile, the T-wave loop anterior-posterior pattern evidenced sensitivity of 95% vs. 77% and specificity of 91% vs. 87% (p < 0.0001 vs. p = 0.04), respectively. The electrovectorcardiographic parameters showed high accuracy for recognizing left ventricular aneurysms in ischemic heart disease.

Prognostic Evaluation of Microvolt T-Wave Alternans in Hypertrophic Cardiomyopathy: 9-year Clinical Follow-up. / Avaliação Prognóstica da Microalternância da onda T na Cardiomiopatia Hipertrófica em um Seguimento Clínico de 9 anos.

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.

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%: 0,21­3,35, 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.

Favorable Safety Experience of Local Dental Anesthesia in ICD Recipients with Cardiac Channelopathies

Abstract Background Dental anesthetic management in implantable cardioverter defibrillator (ICD) recipients with cardiac channelopathies (CCh) can be challenging due to the potential risk of life-threatening arrhythmias and appropriate ICD therapies during procedural time. Objectives The present study assessed the hypothesis that the use of local dental anesthesia with 2% lidocaine with 1:100,000 epinephrine or without a vasoconstrictor can be safe in selected ICD and CCh patients, not resulting in life-threatening events (LTE). Methods Restorative dental treatment under local dental anesthesia was made in two sessions, with a wash-out period of 7 days (cross-over trial), conducting with a 28h - Holter monitoring, and 12-lead electrocardiography, digital sphygmomanometry, and anxiety scale assessments in 3 time periods. Statistical analysis carried out the paired Student's t test and the Wilcoxon signed-rank test. In all cases, a significance level of 5% was adopted. All patients were in stable condition with no recent events before dental care. Results Twenty-four consecutive procedures were performed in 12 patients (9 women, 3 men) with CCh and ICD: 7 (58.3%) had long QT syndrome (LQTS), 4 (33.3%) Brugada syndrome (BrS), and 1 (8.3%) Catecholaminergic polymorphic ventricular tachycardia (CPVT). Holter analysis showed no increased heart rate (HR) or sustained arrhythmias. Blood pressure (BP), electrocardiographic changes and anxiety measurement showed no statistically significant differences. No LTE occurred during dental treatment, regardless of the type of anesthesia. Conclusion Lidocaine administration, with or without epinephrine, can be safely used in selected CCh-ICD patients without LTE. These preliminary findings need to be confirmed in a larger population with ICD and CCh.

Avaliação Prognóstica da Microalternância da onda T na Cardiomiopatia Hipertrófica em um Seguimento Clínico de 9 anos / Prognostic Evaluation of Microvolt T-Wave Alternans in Hypertrophic Cardiomyopathy: 9-year Clinical Follow-up

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.

Modified moving average methodology applied to the treadmill stress testing analysis of microvolt T-wave alternans.

Sudden cardiac death is impactful. There has been an increase in the search for tools capable of identifying individuals who are most susceptible, such as the microvolt T-wave alternans. This study aims to analyze the applicability of the modified moving average methodology to obtain the microvolt T-wave alternans using treadmill specific protocols. Medical records of patients during the period August 2006-December 2014 were retrospectively analyzed. Five hundred and thirty nine exams were then included, divided into groups according to the protocol and updating factor used: Ellestad factor 8 or 32, Naughton factor 8 or 32. The topics for analysis were the alternans behavior, noise and confirmation according to the groups of leads analyzed (frontal, transversal and orthogonal planes). The greater microvolt T-wave alternans was found during the stress phase in most of the tests. Group Naughton 8 presented lower noise in this phase for the transverse and orthogonal planes (p = 0.0082 and p < 0.0001), with greater confirmation of frontal and orthogonal planes in comparison with group Ellestad 8 (p = 0.0002 and 0.0008). The results indicate the viability of simultaneous performance of the stress test and measurement of the T wave alternans with Naughton protocol with 1/8 updating factor.

Avaliação Eletrocardiográfica de Recém-Nascidos Normais na Primeira Semana de Vida - Estudo Observacional / Electrocardiographic Evaluation of Normal Newborns in the First Week of Life - Observational Study

Resumo Fundamento O período neonatal é marcado por muitas alterações importantes no sistema cardiovascular, principalmente na primeira semana de vida. Diferentemente da população adulta, estudos sobre dados de eletrocardiograma (ECG) no período neonatal são escassos. Este é o primeiro estudo a descrever alterações eletrocardiográficas em uma coorte de recém-nascidos com ecocardiogramas normais. Objetivos Analisar padrões eletrocardiográficos de uma população de recém-nascidos a termo, sem anomalias morfológicas ou funcionais cardíacas, e comparar os resultados com a literatura. Métodos Neste estudo observacional, ecocardiogramas e resultados de ECG de 94 neonatos divididos em três grupos etários (até 24 horas, entre 25 e 72 horas, e entre 73 e 168 horas de vida) foram avaliados e comparados com aqueles descritos por Davignon et al. Um valor de p < 0,05 foi considerado estatisticamente significativo. Resultados Diferenças significativas na direção da onda T foram detectadas nas derivações V1 (p= 0,04), V2 (p= 0,02), V3 (p= 0,008) e V4 (p= 0,005). Houve diferenças entre nossos resultados e a literatura atual na maioria dos parâmetros. Conclusão Recém-nascidos a termo com menos de 24 horas de vida apresentaram significativamente mais ondas T positivas que aqueles com mais horas de vida. Encontramos muitas diferenças nos parâmetros de ECG em comparação aos descritos por Davignon et al., particularmente nas amplitudes de P, Q, R, S, duração do QRS, R/S e R+S. Esses achados indicam a necessidade de mais estudos para uma interpretação definitiva do ECG em recém-nascidos.

Abstract Background The neonatal period is marked by major changes in the cardiovascular system, especially in the first week of life. Unlike the adult population, studies on electrocardiogram (ECG) data in the neonatal period are scarce. This is the first study to describe electrocardiographic changes in a cohort of newborns with normal echocardiograms. Objectives To analyze the electrocardiographic patterns of a population of full-term NB, without any cardiac morphological or functional anomalies, and compare the results with the literature. Methods In this observational study, echocardiograms and ECG results from 94 newborns divided in three age groups (up to 24 hours, between 25 and 72 hours, and between 73 and 168 hours of life) were evaluated and compared with those reported by Davignon et al. A p-value <0.05 was considered statistically significant. Results There were significant differences in T-wave direction in leads V1 (p= 0.04), V2 (p= 0.02), V3 (p= 0.008) and V4 (p= 0.005) between the three age groups. There were differences between our findings and the current literature in most of the parameters. Conclusion Term newborns within 24 hours of life showed significantly more positive T waves than older ones. Many differences from the Davignon's ECG parameters were found, particularly in the P, Q, R, S amplitudes, QRS duration, R/S and R+S. These findings indicate that more studies are needed for a definitive interpretation of the ECG in newborns.

Electrocardiographic Evaluation of Normal Newborns in the First Week of Life - Observational Study. / Avaliação Eletrocardiográfica de Recém-Nascidos Normais na Primeira Semana de Vida ­ Estudo Observacional.

BACKGROUND: The neonatal period is marked by major changes in the cardiovascular system, especially in the first week of life. Unlike the adult population, studies on electrocardiogram (ECG) data in the neonatal period are scarce. This is the first study to describe electrocardiographic changes in a cohort of newborns with normal echocardiograms. OBJECTIVES: To analyze the electrocardiographic patterns of a population of full-term NB, without any cardiac morphological or functional anomalies, and compare the results with the literature. METHODS: In this observational study, echocardiograms and ECG results from 94 newborns divided in three age groups (up to 24 hours, between 25 and 72 hours, and between 73 and 168 hours of life) were evaluated and compared with those reported by Davignon et al. A p-value <0.05 was considered statistically significant. RESULTS: There were significant differences in T-wave direction in leads V1 (p= 0.04), V2 (p= 0.02), V3 (p= 0.008) and V4 (p= 0.005) between the three age groups. There were differences between our findings and the current literature in most of the parameters. CONCLUSION: Term newborns within 24 hours of life showed significantly more positive T waves than older ones. Many differences from the Davignon's ECG parameters were found, particularly in the P, Q, R, S amplitudes, QRS duration, R/S and R+S. These findings indicate that more studies are needed for a definitive interpretation of the ECG in newborns.

FUNDAMENTO: O período neonatal é marcado por muitas alterações importantes no sistema cardiovascular, principalmente na primeira semana de vida. Diferentemente da população adulta, estudos sobre dados de eletrocardiograma (ECG) no período neonatal são escassos. Este é o primeiro estudo a descrever alterações eletrocardiográficas em uma coorte de recém-nascidos com ecocardiogramas normais. OBJETIVOS: Analisar padrões eletrocardiográficos de uma população de recém-nascidos a termo, sem anomalias morfológicas ou funcionais cardíacas, e comparar os resultados com a literatura. MÉTODOS: Neste estudo observacional, ecocardiogramas e resultados de ECG de 94 neonatos divididos em três grupos etários (até 24 horas, entre 25 e 72 horas, e entre 73 e 168 horas de vida) foram avaliados e comparados com aqueles descritos por Davignon et al. Um valor de p < 0,05 foi considerado estatisticamente significativo. RESULTADOS: Diferenças significativas na direção da onda T foram detectadas nas derivações V1 (p= 0,04), V2 (p= 0,02), V3 (p= 0,008) e V4 (p= 0,005). Houve diferenças entre nossos resultados e a literatura atual na maioria dos parâmetros. CONCLUSÃO: Recém-nascidos a termo com menos de 24 horas de vida apresentaram significativamente mais ondas T positivas que aqueles com mais horas de vida. Encontramos muitas diferenças nos parâmetros de ECG em comparação aos descritos por Davignon et al., particularmente nas amplitudes de P, Q, R, S, duração do QRS, R/S e R+S. Esses achados indicam a necessidade de mais estudos para uma interpretação definitiva do ECG em recém-nascidos.

Usefulness of ECG criteria to rule out left ventricular hypertrophy in older individuals with true left bundle branch block: an observational study.

BACKGROUND: Advanced age is associated with both left bundle branch block (LBBB) and hypertension and the usefulness of ECG criteria to detect left ventricular hypertrophy (LVH) in patients with LBBB is still unclear. The diagnostic performance and clinical applicability of ECG-based LVH criteria in patients with LBBB defined by stricter ECG criteria is unknown. The aim of this study was to compare diagnostic accuracy and clinical utility of ECG criteria in patients with advanced age and strict LBBB criteria. METHODS: Retrospective single-center study conducted from Jan/2017 to Mar/2018. Patients undergoing both ECG and echocardiogram examinations were included. Ten criteria for ECG-based LVH were compared using LVH defined by the echocardiogram as the gold standard. Sensitivity, specificity, predictive values, likelihood ratios, AUC, and the Brier score were used to compare diagnostic performance and a decision curve analysis was performed. RESULTS: From 4621 screened patients, 68 were included, median age was 78.4 years, (IQR 73.3-83.4), 73.5% with hypertension. All ECG criteria failed to provide accurate discrimination of LVH with AUC range between 0.54 and 0.67, and no ECG criteria had a balanced tradeoff between sensitivity and specificity. No ECG criteria consistently improved the net benefit compared to the strategy of performing routine echocardiogram in all patients in the decision curve analysis within the 10-60% probability threshold range. CONCLUSION: ECG-based criteria for LVH in patients with advanced age and true LBBB lack diagnostic accuracy or clinical usefulness and should not be routinely assessed.

Clinical applicability and diagnostic performance of electrocardiographic criteria for left ventricular hypertrophy diagnosis in older adults.

Recently, a new ECG criterion, the Peguero-Lo Presti (PLP), improved overall accuracy in the diagnosis of left ventricular hypertrophy (LVH)-compared to traditional ECG criteria, but with few patients with advanced age. We analyzed patients with older age and examined which ECG criteria would have better overall performance. A total of 592 patients were included (83.1% with hypertension, mean age of 77.5 years) and the PLP criterion was compared against Cornell voltage (CV), Sokolow-Lyon voltage (SL) and Romhilt-Estes criteria (cutoffs of 4 and 5 points, RE4 and RE5, respectively) using LVH defined by the echocardiogram as the gold standard. The PLP had higher AUC than the CV, RE and SL (respectively, 0.70 vs 0.66 vs 0.64 vs 0.67), increased sensitivity compared with the SL, CV and RE5 (respectively, 51.9% [95% CI 45.4-58.3%] vs 28.2% [95% CI 22.6-34.4%], p < 0.0001; vs 35.3% [95% CI 29.2-41.7%], p < 0.0001; vs 44.4% [95% CI 38.0-50.9%], p = 0.042), highest F1 score (58.3%) and net benefit for most of the 20-60% threshold range in the decision curve analysis. Overall, despite the best diagnostic performance in older patients, the PLP criterion cannot rule out LVH consistently but can potentially be used to guide clinical decision for echocardiogram ordering in low-resource settings.

Andersen-Tawil Syndrome: A Comprehensive Review.

Andersen-Tawil syndrome (ATS) is a very rare orphan genetic multisystem channelopathy without structural heart disease (with rare exceptions). ATS type 1 is inherited in an autosomal dominant fashion and is caused by mutations in the KCNJ2 gene, which encodes the α subunit of the K+ channel protein Kir2.1 (in ≈ 50-60% of cases). ATS type 2 is in turn linked to a rare mutation in the KCNJ5-GIRK4 gene that encodes the G protein-sensitive-activated inwardly rectifying K+ channel Kir3.4 (15%), which carries the acetylcholine-induced potassium current. About 30% of cases are de novo/sporadic, suggesting that additional as-yet unidentified genes also cause the disorder. A triad of periodic muscle paralysis, repolarization changes in the electrocardiogram, and structural body changes characterize ATS. The typical muscular change is episodic flaccid muscle weakness. Prolongation of the QU/QUc intervals and normal or minimally prolonged QT/QTc intervals with a tendency to ventricular arrhythmias are typical repolarization changes. Bidirectional ventricular tachycardia is the hallmark ventricular arrhythmia, but also premature ventricular contractions, and rarely, polymorphic ventricular tachycardia of torsade de pointes type may be present. Patients with ATS have characteristic physical developmental dysmorphisms that affect the face, skull, limbs, thorax, and stature. Mild learning difficulties and a distinct neurocognitive phenotype (deficits in executive function and abstract reasoning) have been described. About 60% of affected individuals have all features of the major triad. The purpose of this review is to present historical aspects, nomenclature (observations/criticisms), epidemiology, genetics, electrocardiography, arrhythmias, electrophysiological mechanisms, diagnostic criteria/clues of periodic paralysis, prognosis, and management of ATS.

Ventricular repolarization abnormalities: the electrocardiographic track of cardiac tumoural involvement in an infant with tuberous sclerosis complex. A case report.

BACKGROUND: Primary cardiac tumours are rare in children. Against this backdrop, Doppler echocardiogram is the main diagnostic procedure, while electrocardiogram (ECG) usually plays a secondary role, by detecting tumoural consequences as cardiac arrhythmias and chambers overload. We describe a case where an electrocardiographic sign was the cornerstone to diagnosis and surveillance of an infant with a cardiac rhabdomyoma. CASE SUMMARY: A female infant was referred for cardiac evaluation to elucidate an electrocardiographic abnormality, detected during investigation of seizures. She had recently been diagnosed with epilepsy and was under three different anticonvulsants for appropriate control. Cardiovascular symptoms were absent. Skin inspection revealed hypochromic macules. Respiratory and cardiovascular examinations were normal, as well as laboratorial tests and chest radiography. Electrocardiogram (ECG) showed dome-shaped ST-segment elevation in V2 and V3. Transthoracic echocardiogram unveiled a single hyper-echogenic node (0.4 cm2) in the interventricular septum. Cardiac chambers had normal size and function and Doppler analysis was also normal. No specific medication was used to treat the tumour. During follow-up, she remained free of cardiac symptoms. Eighteen months after her first visit to the cardiologist, routine clinical assessment, ECG, and transthoracic Doppler echocardiogram normal results stated the spontaneous and complete involution of the tumoural lesion. DISCUSSION: Convex ST-segment elevation, generally related to myocardial injury, is unusual in paediatric patients. Once it occurs in asymptomatic individuals within this age bracket, exclusion of cardiac tumours is mandatory. However, data regarding the accuracy of such electrocardiographic marker in this clinical setting are still to be defined.