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101.
Yoav Michowitz Anat Milman Antoine Andorin Georgia Sarquella-Brugada M. Cecilia Gonzalez Corcia Jean-Baptiste Gourraud Giulio Conte Frederic Sacher Jimmy J.M. Juang Sung-Hwan Kim Eran Leshem Philippe Mabo Pieter G. Postema Aviram Hochstadt Yanushi D. Wijeyeratne Isabelle Denjoy Carla Giustetto Yuka Mizusawa Bernard Belhassen 《Journal of the American College of Cardiology》2019,73(14):1756-1765
Background
Information on young patients with Brugada syndrome (BrS) and arrhythmic events (AEs) is limited.Objectives
The purpose of this study was to describe their characteristics and management as well as risk factors for AE recurrence.Methods
A total of 57 patients (age ≤20 years), all with BrS and AEs, were divided into pediatric (age ≤12 years; n = 26) and adolescents (age 13 to 20 years; n = 31).Results
Patients’ median age at time of first AE was 14 years, with a majority of males (74%), Caucasians (70%), and probands (79%) who presented as aborted cardiac arrest (84%). A significant proportion of patients (28%) exhibited fever-related AE. Family history of sudden cardiac death (SCD), prior syncope, spontaneous type 1 Brugada electrocardiogram (ECG), inducible ventricular fibrillation at electrophysiological study, and SCN5A mutations were present in 26%, 49%, 65%, 28%, and 58% of patients, respectively. The pediatric group differed from the adolescents, with a greater proportion of females, Caucasians, fever-related AEs, and spontaneous type-1 ECG. During follow-up, 68% of pediatric and 64% of adolescents had recurrent AE, with median time of 9.9 and 27.0 months, respectively. Approximately one-third of recurrent AEs occurred on quinidine therapy, and among the pediatric group, 60% of recurrent AEs were fever-related. Risk factors for recurrent AE included sinus node dysfunction, atrial arrhythmias, intraventricular conduction delay, or large S-wave on ECG lead I in the pediatric group and the presence of SCN5A mutation among adolescents.Conclusions
Young BrS patients with AE represent a very arrhythmogenic group. Current management after first arrhythmia episode is associated with high recurrence rate. Alternative therapies, besides defibrillator implantation, should be considered. 相似文献102.
Meredith Bryarly Lauren T. Phillips Qi Fu Steven Vernino Benjamin D. Levine 《Journal of the American College of Cardiology》2019,73(10):1207-1228
Postural orthostatic tachycardia syndrome (POTS), the most common form of orthostatic intolerance in young people, affects approximately 500,000 people in the United States alone, typically young women at the peak of their education and the beginning of their working lives. This is a heterogeneous disorder, the pathophysiology and mechanisms of which are not well understood. There are multiple contributing factors and numerous potential mimics. This review details the most current views on the potential causes, comorbid conditions, proposed subtypes, differential diagnoses, evaluations, and treatment of POTS from cardiological and neurological perspectives. 相似文献
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《Scandinavian cardiovascular journal : SCJ》2013,47(5):241-248
AbstractAims. The relationship between the heart rate of ventricular tachycardia (VT) and the transmurality of ischemic scars was assessed by a new semiautomatic coordinate-based analysis of late gadolinium-enhanced cardiac magnetic resonance (LGE-CMR) images. Methods and results. Twenty patients assessed by LGE-CMR before implantation of implantable cardioverter defibrillator (ICD) with verified VT during the first year following ICD implantation were included. Scar was defined by pixels with a signal intensity ≥ 50% of maximum signal intensity. All pixels were assigned a coordinate position between endo- and epicardium (λ) and the angle of the heart axis (φ). Based upon the λ and φ values, multiple scar features were computed for all scarred areas. These features were correlated to VT heart rate across the complete range of transmurality. The strongest correlation with univariate regression was found between VT heart rate and the sum of transmurality when the maximum transmurality of these features was ≥ 90% (R-square = 0.47). In multiple regressions analysis, the strongest relationship with VT heart rate was found with a maximum transmurality ≥ 90% and by a combination of scar size, transmurality, and endocardial extent of infarction (R-square = 0.64). Conclusion. Transmurality is the strongest predictor of VT heart rate both in univariate and multivariate models. The strongest relationships were found at a transmurality level > 90%. 相似文献
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《Journal of the American College of Cardiology》2020,75(8):884-897
BackgroundMechanisms of scar-related ventricular tachycardia (VT) are largely based on computational and animal models that portray a 2-dimensional view.ObjectivesThe authors sought to delineate the human VT circuit with a 3-dimensional perspective from recordings obtained by simultaneous endocardial and epicardial mapping.MethodsHigh-resolution mapping was performed during 97 procedures in 89 patients with structural heart disease. Circuits were characterized by systematic isochronal analysis to estimate the dimensions of the isthmus and extent of the exit region recorded on both myocardial surfaces.ResultsA total of 151 VT morphologies were mapped, of which 83 underwent simultaneous endocardial and epicardial mapping; 17% of circuits activated in a 2-dimensional plane, restricted to 1 myocardial surface. Three-dimensional activation patterns with nonuniform transmural propagation were observed in 61% of circuits with only 4% showing transmurally uniform activation, and 18% exhibiting focal activation patterns consistent with mid-myocardial reentry. The dimensions of the central isthmus were 17 mm (12 to 28 mm) × 10 mm (9 to 19 mm) with 55% exhibiting a minimal dimension of <1.5 cm. QRS activation was transmural in 63% and located 43 mm (34 to 52 mm) from the central isthmus. On the basis of 6 proposed definitions for epicardial VT, the prevalence of an epicardial circuit ranged from 21% to 80% in ischemic cardiomyopathy and 28% to 77% in nonischemic cardiomyopathy.ConclusionsA 2D perspective oversimplifies the electrophysiological circuit responsible for reentrant human VT and simultaneous endocardial and epicardial mapping facilitates inferences about mid-myocardial activation. Intricate activation patterns are frequently observed on both myocardial surfaces, and the epicardium is functionally involved in the majority of circuits. Human reentry may exist within isthmus dimensions smaller than 1 cm, whereas QRS activation is often transmural and remote from the critical isthmus target. A 3-dimensional perspective of the VT circuit may enhance the precision of ablative therapy and may support a greater role for adjunctive strategies and technology to address arrhythmogenic tissue harbored in the mid-myocardium and subepicardium. 相似文献
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