Childhood Hypertrophic Obstructive Cardiomyopathy and Its Relevant Surgical Outcome.

BACKGROUND:Contemporary experiences regarding childhood hypertrophic obstructive cardiomyopathy are limited. This study aimed to describe the clinical presentation of childhood hypertrophic obstructive cardiomyopathy and its relevant surgical outcome.METHODS:In all, 117 consecutive children with hypertrophic obstructive cardiomyopathy aged 0.6 to 17.5 years who underwent septal myectomy at our institution between February 2009 and December 2018 were included. Medical records and other patient-related data were reviewed.RESULTS:In the present study, the anatomic and physiologic characteristics of childhood hypertrophic obstructive cardiomyopathy were highly heterogeneous, with simultaneous right ventricular outflow tract obstruction in 22 patients (18.8%), coronary myocardial bridging in 25 patients (21.4%), and intraventricular anatomic abnormalities in 61 patients (52.1%). The mean peak left or right ventricular outflow tract gradient, interventricular septal thickness, and degree of mitral regurgitation significantly decreased after surgery. One early death was noted in the study. During follow-up, three sudden cardiac deaths were noted. The overall survival rates at follow-up were 100% at 1 year and 96.5% at 3 years. The overall survival rates free from reoperation were 99.1% at 1 year and 98.0% at 3 years.CONCLUSIONS:In our cohort of children with hypertrophic obstructive cardiomyopathy undergoing septal myectomy, biventricular obstruction, myocardial bridging, and intraventricular anatomic abnormalities are frequent phenotypic components. Despite the complexity of childhood hypertrophic obstructive cardiomyopathy, surgical treatment results in a favorable outcome in carefully selected patients.

The co-segregation of the MYL2 R58Q mutation in Chinese hypertrophic cardiomyopathy family and its pathological effect on cardiomyopathy disarray.

Hypertrophic cardiomyopathy (HCM), a major cause of sudden death in youth, is largely affected by genetic factors. The R58Q mutation in the MYL2 gene was identified in some HCM patients and was considered as a deleterious HCM mutation. However, the passing of R58Q between generations along with HCM symptoms was observed only in small families with only two or three members; thus, whether R58Q is as deleterious as previously claimed remains questionable. Here, we reported a large four-generation Chinese family, and found that R58Q existed in all six members with HCM and two healthy juveniles who had not yet developed HCM yet, and presumably in three deceased members who suffered from sudden death. In addition, we also found that compared with other mutations, R58Q had a more severe effect on the cellular level. Therefore, we confirmed that R58Q could be passed from generation to generation along with HCM symptoms and that it was indeed a deleterious mutation for HCM. However, further study is needed to identify additional factors that may determine the various symptoms shown in different family members within the same family.

Long non-coding and coding RNA profiling using strand-specific RNA-seq in human hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) represents one of the most common heritable heart diseases. However, the signalling pathways and regulatory networks underlying the pathogenesis of HCM remain largely unknown. Here, we present a strand-specific RNA-seq dataset for both coding and lncRNA profiling in myocardial tissues from 28 HCM patients and 9 healthy donors. This dataset constitutes a valuable resource for the community to examine the dysregulated coding and lncRNA genes in HCM versus normal conditions.

Secondary findings in 421 whole exome-sequenced Chinese children.

BACKGROUND:Variants with known or possible pathogenicity located in genes that are unrelated to primary disease conditions are defined as secondary findings. Secondary findings are not the primary targets of whole exome and genome sequencing (WES/WGS) assay but can be of great practical value in early disease prevention and intervention. The driving force for this study was to investigate the impact of racial difference and disease background on secondary findings. Here, we analyzed secondary findings frequencies in 421 whole exome-sequenced Chinese children who are phenotypically normal or bear congenital heart diseases/juvenile obesity. In total, 421 WES datasets were processed for potential deleterious variant screening. A reference gene list was defined according to the American College of Medical Genetics and Genomics (ACMG) recommendations for reporting secondary findings v2.0 (ACMG SF v2.0). The variant classification was performed according to the evidence-based guidelines recommended by the joint consensus of the ACMG and the Association for Molecular Pathology (AMP).RESULTS:Among the 421 WES datasets, we identified 11 known/expected pathogenic variants in 12 individuals, accounting for 2.85% of our samples, which is much higher than the reported frequency in a Caucasian population. In conclusion, secondary findings are not so rare in Chinese children, which means that we should pay more attention to the clinical interpretation of sequencing results.

Letter by Ma et al Regarding Article, "Novel Mutation in FLNC (Filamin C) Causes Familial Restrictive Cardiomyopathy".

Childhood Hypertrophic Obstructive Cardiomyopathy and Its Relevant Surgical Outcome.

BACKGROUND:Contemporary experiences regarding childhood hypertrophic obstructive cardiomyopathy are limited. This study aimed to describe the clinical presentation of childhood hypertrophic obstructive cardiomyopathy and its relevant surgical outcome.METHODS:In all, 117 consecutive children with hypertrophic obstructive cardiomyopathy aged 0.6 to 17.5 years who underwent septal myectomy at our institution between February 2009 and December 2018 were included. Medical records and other patient-related data were reviewed.RESULTS:In the present study, the anatomic and physiologic characteristics of childhood hypertrophic obstructive cardiomyopathy were highly heterogeneous, with simultaneous right ventricular outflow tract obstruction in 22 patients (18.8%), coronary myocardial bridging in 25 patients (21.4%), and intraventricular anatomic abnormalities in 61 patients (52.1%). The mean peak left or right ventricular outflow tract gradient, interventricular septal thickness, and degree of mitral regurgitation significantly decreased after surgery. One early death was noted in the study. During follow-up, three sudden cardiac deaths were noted. The overall survival rates at follow-up were 100% at 1 year and 96.5% at 3 years. The overall survival rates free from reoperation were 99.1% at 1 year and 98.0% at 3 years.CONCLUSIONS:In our cohort of children with hypertrophic obstructive cardiomyopathy undergoing septal myectomy, biventricular obstruction, myocardial bridging, and intraventricular anatomic abnormalities are frequent phenotypic components. Despite the complexity of childhood hypertrophic obstructive cardiomyopathy, surgical treatment results in a favorable outcome in carefully selected patients.

The co-segregation of the MYL2 R58Q mutation in Chinese hypertrophic cardiomyopathy family and its pathological effect on cardiomyopathy disarray.

Hypertrophic cardiomyopathy (HCM), a major cause of sudden death in youth, is largely affected by genetic factors. The R58Q mutation in the MYL2 gene was identified in some HCM patients and was considered as a deleterious HCM mutation. However, the passing of R58Q between generations along with HCM symptoms was observed only in small families with only two or three members; thus, whether R58Q is as deleterious as previously claimed remains questionable. Here, we reported a large four-generation Chinese family, and found that R58Q existed in all six members with HCM and two healthy juveniles who had not yet developed HCM yet, and presumably in three deceased members who suffered from sudden death. In addition, we also found that compared with other mutations, R58Q had a more severe effect on the cellular level. Therefore, we confirmed that R58Q could be passed from generation to generation along with HCM symptoms and that it was indeed a deleterious mutation for HCM. However, further study is needed to identify additional factors that may determine the various symptoms shown in different family members within the same family.

Long non-coding and coding RNA profiling using strand-specific RNA-seq in human hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) represents one of the most common heritable heart diseases. However, the signalling pathways and regulatory networks underlying the pathogenesis of HCM remain largely unknown. Here, we present a strand-specific RNA-seq dataset for both coding and lncRNA profiling in myocardial tissues from 28 HCM patients and 9 healthy donors. This dataset constitutes a valuable resource for the community to examine the dysregulated coding and lncRNA genes in HCM versus normal conditions.

Secondary findings in 421 whole exome-sequenced Chinese children.

BACKGROUND:Variants with known or possible pathogenicity located in genes that are unrelated to primary disease conditions are defined as secondary findings. Secondary findings are not the primary targets of whole exome and genome sequencing (WES/WGS) assay but can be of great practical value in early disease prevention and intervention. The driving force for this study was to investigate the impact of racial difference and disease background on secondary findings. Here, we analyzed secondary findings frequencies in 421 whole exome-sequenced Chinese children who are phenotypically normal or bear congenital heart diseases/juvenile obesity. In total, 421 WES datasets were processed for potential deleterious variant screening. A reference gene list was defined according to the American College of Medical Genetics and Genomics (ACMG) recommendations for reporting secondary findings v2.0 (ACMG SF v2.0). The variant classification was performed according to the evidence-based guidelines recommended by the joint consensus of the ACMG and the Association for Molecular Pathology (AMP).RESULTS:Among the 421 WES datasets, we identified 11 known/expected pathogenic variants in 12 individuals, accounting for 2.85% of our samples, which is much higher than the reported frequency in a Caucasian population. In conclusion, secondary findings are not so rare in Chinese children, which means that we should pay more attention to the clinical interpretation of sequencing results.

Letter by Ma et al Regarding Article, "Novel Mutation in FLNC (Filamin C) Causes Familial Restrictive Cardiomyopathy".