Humans ; Tachycardia, Ventricular ; genetics

Andersen Syndrome/genetics* ; Humans ; Syncope ; Tachycardia, Ventricular

Humans ; Cardiomyopathy, Hypertrophic/genetics* ; Mutation ; Phenotype ; Ryanodine Receptor Calcium Release Channel/genetics* ; Tachycardia, Ventricular/genetics*

Humans ; Cardiomyopathy, Hypertrophic/genetics* ; Mutation ; Phenotype ; Ryanodine Receptor Calcium Release Channel/genetics* ; Tachycardia, Ventricular/genetics*

Electrocardiography ; Humans ; Mutation ; Phosphorylation ; Ryanodine Receptor Calcium Release Channel/genetics* ; Tachycardia, Ventricular/genetics*

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a familial cardiac arrhythmia that is related to RYR2 or CASQ2 gene mutation. It occurs in patients with structurally normal heart and causes exercise-emotion-triggered syncope and sudden cardiac death. We experienced a case of CPVT in an 11 year-old female patient who was admitted for sudden cardiovascular collapse. The initial electrocardiogram (ECG) on emergency department revealed ventricular fibrillation. After multiple defibrillations, sinus rhythm was restored. However, recurrent ventricular fibrillation occurred during insertion of nasogastric tube without sedation in coronary care unit. On ECG monitoring, bidirectional ventricular tachycardia occurred with sinus tachycardia and then degenerated into ventricular fibrillation. To our knowledge, there has been no previous case report of CPVT triggered by sinus tachycardia in Korea. Therefore, we report the case as well as a review of the literature.
Catecholamines/*metabolism ; Child ; Electrocardiography ; Female ; Humans ; Tachycardia, Ventricular/*diagnosis/genetics/pathology

Adolescent ; Calsequestrin ; genetics ; Child ; Child, Preschool ; China ; Diagnostic Errors ; Female ; Humans ; Male ; Tachycardia, Ventricular ; diagnosis

OBJECTIVE: To explore the clinical and genetic characteristics of five children with Catecholaminergic polymorphic ventricular tachycardia (CPVT). METHODS: Five children with clinical manifestations consistent with CPVT admitted to the Department of Cardiology of Children's Hospital Affiliated to Zhengzhou University from November 2019 to November 2021 were selected as the study subjects. Their clinical data were collected. Potential variants were detected by whole exome sequencing, and Sanger sequencing was used to verify the candidate variants. All patients were treated with β-blocker propranolol and followed up. RESULTS: All patients had developed the disease during exercise and presented with syncope as the initial clinical manifestation. Electrocardiogram showed sinus bradycardia. The first onset age of the 5 patients were (10.4 ± 2.19) years, and the time of delayed diagnosis was (1.6 ± 2.19) years. All of the children were found to harbor de novo heterozygous missense variants of the RYR2 gene, including c.6916G>A (p.V2306I), c.527G>C (p.R176P), c.12271G>A (p.A4091T), c.506G>T (p.R169L) and c.6817G>A (p.G2273R). Among these, c.527G>C (p.R176P) and c.6817G>A (p.G2273R) were unreported previously. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c.527G>C (p.R176P) was classified as a pathogenic variant (PS2+PM1+PM2_Supporting+PM5+PP3+PP4), and the c.6817G>A (p.G2273R) was classified as a likely pathogenic variant (PS2+PM2_Supporting+PP3+PP4). The symptoms of all children were significantly improved with the propranolol treatment, and none has developed syncope during the follow up. CONCLUSION Discovery of the c.527G>C (p.R176P) and c.6817G>A (p.G2273R) variants has expanded the mutational spectrum of the RYR2 gene. Genetic testing of CPVT patients can clarify the cause of the disease and provide a reference for their genetic counseling.
Child ; Humans ; Mutation ; Propranolol ; Ryanodine Receptor Calcium Release Channel/genetics* ; Syncope ; Tachycardia, Ventricular/diagnosis* ; United States

OBJECTIVETo identify mutations and variants in CASQ2 gene in 27 CPVT patients/family members.

METHODSMutational analysis was performed with direct DNA sequence analysis. The frequency of an identified CASQ2 variant was determined using the Taqman genotyping assay.

RESULTSA novel heterozygous mutation, F189L, in CASQ2 gene was identified in one family with CPVT. This mutation occurred at the evolutionarily, highly conserved phenylalanine residue at codon 189, and was not present in 1400 control individuals. No other disease-causing mutations were identified in the CASQ2 gene.

CONCLUSIONA novel mutation of F189L in the CASQ2 gene was identified.

Calsequestrin ; genetics ; DNA Mutational Analysis ; Genetic Predisposition to Disease ; genetics ; Genotype ; Humans ; Male ; Mutation ; Pedigree ; Tachycardia, Ventricular ; genetics ; Young Adult

Patients with long QT syndrome can sometimes present with a ventricular fibrillation (VF) storm. Catheter ablation of culprit premature ventricular complexes responsible for the triggering of the VF episodes may be required in rare cases of electrical storm that do not respond to conventional measures, and this can be life-saving. We describe a case of emergency catheter ablation in a young woman with a normal corrected QT interval, who presented with malignant VF storm for the first time. We also discuss the diagnostic and management challenges involved, as well as the value of genetic testing in refining the diagnosis.
Cardiology ; Catheter Ablation ; methods ; Electrocardiography ; methods ; Female ; Heart Arrest ; genetics ; therapy ; Heterozygote ; Humans ; Long QT Syndrome ; genetics ; Tachycardia, Ventricular ; therapy ; Treatment Outcome ; Ventricular Fibrillation ; therapy ; Ventricular Premature Complexes ; genetics ; therapy ; Young Adult