BACKGROUND: Although genetic variants in MYH7 are the most frequent cause of pediatric genetic dilated cardiomyopathy (DCM), there are no studies available describing this entity. We sought to describe clinical features, analyze variant location, and explore predictors of bad prognosis in pediatric MYH7-related DCM. METHODS AND RESULTS: We evaluated clinical records from 44 patients (24 men; median age at diagnosis, 0.54 [interquartile range, 0.01-10.8] years) with pathogenic/likely pathogenic variants in MYH7 diagnosed with DCM at pediatric age (<18 years) followed at 13 international centers. We also explored risk factors associated with a composite end point of end-stage heart failure defined as heart transplantation or heart failure-related death. Twenty-two patients (50%) were diagnosed at age <6 months, including 7 (16%) at birth. Left ventricular (LV) hypertrabeculation features were present in 15 (38%), particularly among patients with genetic variants in the head domain. After a median follow-up of 6.1 years (interquartile range, 1.9-13.4), 15 patients (36%) required a heart transplant (n=14) or died due to end-stage heart failure (n=1), 15 patients (36%) persisted with systolic dysfunction despite treatment, 12 (29%) had a significant increase in LV ejection fraction, and 2 were lost to follow-up. Overall, end-stage heart failure event rate was 25% at 5 years. New York Heart Association class III to IV (hazard ratio [HR], 7.67 [95% CI, 2.16-27.2]; P=0.002) and LV ejection fraction ≤35% (HR, 4.00 [95% CI, 1.11-14.4]; P=0.03) were the best predictors of bad prognosis. CONCLUSIONS: Pediatric MYH7-related DCM is characterized by early onset, frequent LV hypertrabeculation, and poor prognosis. Advanced New York Heart Association class and low LV ejection fraction emerged as predictors of end-stage heart failure.

• Klíčová slova
• MYH7, dilated cardiomyopathy, genetics, pediatric,
• MeSH
• dilatační kardiomyopatie * genetika   patofyziologie   diagnóza   MeSH
• dítě MeSH
• fenotyp MeSH
• funkce levé komory srdeční MeSH
• genetická predispozice k nemoci MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mutace MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• prognóza MeSH
• retrospektivní studie MeSH
• rizikové faktory MeSH
• srdeční myosiny * genetika   MeSH
• srdeční selhání genetika   patofyziologie   diagnóza   MeSH
• těžké řetězce myosinu * genetika   MeSH
• transplantace srdce * MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• Názvy látek
• MYH7 protein, human MeSH Prohlížeč
• srdeční myosiny * MeSH
• těžké řetězce myosinu * MeSH

Left ventricular noncompaction cardiomyopathy is associated with heart failure, arrhythmia, and sudden cardiac death. The developmental mechanism underpinning noncompaction in the adult heart is still not fully understood, with lack of trabeculae compaction, hypertrabeculation, and loss of proliferation cited as possible causes. To study this, we utilised a mouse model of aberrant Rho kinase (ROCK) signalling in cardiomyocytes, which led to a noncompaction phenotype during embryogenesis, and monitored how this progressed after birth and into adulthood. The cause of the early noncompaction at E15.5 was attributed to a decrease in proliferation in the developing ventricular wall. By E18.5, the phenotype became patchy, with regions of noncompaction interspersed with thick compacted areas of ventricular wall. To study how this altered myoarchitecture of the heart influenced impulse propagation in the developing and adult heart, we used histology with immunohistochemistry for gap junction protein expression, optical mapping, and electrocardiography. At the prenatal stages, a clear reduction in left ventricular wall thickness, accompanied by abnormal conduction of the ectopically paced beat in that area, was observed in mutant hearts. This correlated with increased expression of connexin-40 and connexin-43 in noncompacted trabeculae. In postnatal stages, left ventricular noncompaction was resolved, but the right ventricular wall remained structurally abnormal through to adulthood with cardiomyocyte hypertrophy and retention of myocardial crypts. Thus, this is a novel model of self-correcting embryonic hypertrabeculation cardiomyopathy, but it highlights that remodelling potential differs between the left and right ventricles. We conclude that disruption of ROCK signalling induces both morphological and electrophysiological changes that evolve over time, highlighting the link between myocyte proliferation and noncompaction phenotypes and electrophysiological differentiation.

• Klíčová slova
• ROCK, cardiomyocyte proliferation, compaction, conduction, mouse embryonic heart, myocardial trabeculae, ventricular wall,
• Publikační typ
• časopisecké články MeSH

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

• Klíčová slova
• Catheter ablation, Clinical document, Electrical storm, Electroanatomical mapping, Electrocardiogram, Expert consensus statement, Imaging, Premature ventricular complex, Radiofrequency ablation, Ventricular arrhythmia, Ventricular tachycardia,
• MeSH
• katetrizační ablace * MeSH
• komorová tachykardie * chirurgie   MeSH
• komorové extrasystoly * MeSH
• konsensus MeSH
• lidé MeSH
• srdeční elektrofyziologie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• metaanalýza MeSH
• systematický přehled MeSH

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

• Klíčová slova
• Catheter ablation, Clinical document, Electrical storm, Electroanatomical mapping, Electrocardiogram, Expert consensus statement, Imaging, Premature ventricular complex, Radiofrequency ablation, Ventricular arrhythmia, Ventricular tachycardia,
• MeSH
• kardiologie * MeSH
• katetrizační ablace normy   MeSH
• komorová tachykardie chirurgie   MeSH
• konsensus * MeSH
• lidé MeSH
• společnosti lékařské * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Research Support, N.I.H., Extramural MeSH

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias.

• Klíčová slova
• Catheter ablation, Clinical document, Electrical storm, Electroanatomical mapping, Electrocardiogram, Expert consensus statement, Imaging, Premature ventricular complex, Radiofrequency ablation, Ventricular arrhythmia, Ventricular tachycardia,
• MeSH
• elektrofyziologické techniky kardiologické metody   MeSH
• katetrizační ablace * přístrojové vybavení   metody   normy   MeSH
• komorová tachykardie * diagnóza   etiologie   patofyziologie   chirurgie   MeSH
• komorové extrasystoly * diagnóza   etiologie   patofyziologie   chirurgie   MeSH
• konsensus MeSH
• lidé MeSH
• mezinárodní spolupráce MeSH
• nemoci srdce klasifikace   komplikace   MeSH
• převodní systém srdeční patologie   patofyziologie   chirurgie   MeSH
• společnosti lékařské MeSH
• srdeční elektrofyziologie * organizace a řízení   normy   trendy   MeSH
• výsledek terapie MeSH
• zlepšení kvality organizace a řízení   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• endokard patologie   MeSH
• fibróza MeSH
• hypertrofie MeSH
• kardiomyocyty patologie   MeSH
• kardiomyopatie vrozené   diagnóza   MeSH
• komorová tachykardie komplikace   MeSH
• lidé MeSH
• mladiství MeSH
• myokard patologie   MeSH
• náhlá srdeční smrt etiologie   MeSH
• srdeční komory patologie   MeSH
• vrozené srdeční vady patologie   MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

This article concerns the development of myocardial architecture--crucial for contractile performance of the heart and its conduction system, essential for generation and coordinated spread of electrical activity. Topics discussed include molecular determination of cardiac phenotype (contractile and conducting), remodeling of ventricular wall architecture and its blood supply, and relation of trabecular compaction to noncompaction cardiomyopathy. Illustrated are the structure and function of the tubular heart, time course of trabecular compaction, and development of multilayered spiral systems of the compact layer.

• MeSH
• embryonální vývoj fyziologie   MeSH
• kardiomyocyty fyziologie   MeSH
• kontrakce myokardu fyziologie   MeSH
• lidé MeSH
• myokard * MeSH
• převodní systém srdeční fyziologie   MeSH
• remodelace komor fyziologie   MeSH
• srdce - funkce komor MeSH
• srdce embryologie   růst a vývoj   fyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, N.I.H., Extramural MeSH