Article

Relationship between dominant prolongation of the filtered QRS duration in the right precordial leads and clinical characteristics in Brugada syndrome.

First Department of Internal Medicine, Niigata University School of Medicine, Niigata, Japan.
Journal of Cardiovascular Electrophysiology (Impact Factor: 2.88). 12/2005; 16(12):1311-7. DOI: 10.1111/j.1540-8167.2005.00262.x
Source: PubMed

ABSTRACT Electrical abnormalities in the RVOT may be involved in Brugada syndrome.
We investigated the relationship between the signal-averaged ECG (SAECG) and electrophysiologic study (EPS), especially focusing on conduction delay in the outflow tract of the right ventricle (RVOT) and its contribution to clinical characteristics.
Twenty-four patients with Brugada syndrome (23 men and 1 woman; 61 +/- 16 years old) were studied. We assessed the presence of late potential (LP) in SAECG and the filtered QRS duration in the right precordial leads (V1 or V2; RfQRS) and in the left precordial leads (V5 or V6; LfQRS) and the difference between them. In 18 patients, SAECG was evaluated for an LP on three separate occasions.
SAECG was positive for LP in 15 patients at least once; and in 7 patients, SAECG was positive for an LP on multiple occasions, and 6 of 7 patients (86%) had a history of cardiac arrest. The difference between RfQRS and LfQRS was significantly greater in patients with cardiac arrest than in patients with syncope or in asymptomatic patients; 29 +/- 10, 14 +/- 11 (P < 0.01), and 7 +/- 5 msec (P < 0.001), respectively. All patients were alive and one patient with cardiac arrest had an appropriate VF therapy delivered by the ICD.
The dominant prolongation of the filtered QRS duration in the right precordial leads may be related to the risk of arrhythmic event in Brugada syndrome.

0 Bookmarks
 · 
56 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: When some 20 years ago the Brugada brothers described the association of life-threatening ventricular arrhythmias with an electrocardiographic (ECG) pattern of RSR' and ST segment elevation in the right precordial leads, in the absence of detectable structural heart disease, they opened a new window to the understanding and the hope of primary prevention of sudden death, particularly in the [apparently] healthy young. This article is protected by copyright. All rights reserved.
    Journal of Cardiovascular Electrophysiology 02/2014; · 3.48 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: SO42−/ZrO2–MoO3 (SZM), SO42−/ZrO2–Nd2O3 (SZN) and SO42−/ZrO2–MoO3–Nd2O3 (SZMN) solid acids catalysts were prepared and characterized by XRD, NH3-FTIR, NH3-TPD and TG–DTG. The activities and stabilities of the catalysts for the esterification of fatty acids were investigated. Experimental and characterization results show that the excellent activity and stability of SZMN are attributed to the firm combination of sulfur species with t-ZrO2. The co-addition of Mo and Nd increases the dispersion of t-ZrO2 and stabilizes the structure of small-crystallite t-ZrO2, which is favorable to increasing the acid sites amount, strengthening the acidity, and then enhancing the activity and stability of the catalyst.
    Applied Catalysis A General 12/2010; 389(1):46-51. · 3.67 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The Brugada syndrome (BrS) is a malignant genetically-determined arrhythmic syndrome manifesting as syncope or sudden cardiac death (SCD) in individuals with structurally normal hearts. The diagnosis of the BrS is mainly based on the presence of a spontaneous or Na+-channel blocker induced characteristic electrocardiographic (ECG) pattern (“type 1” or “coved” Brugada ECG pattern) typically seen in leads V1 and V2 recorded from the 4th to 2nd intercostal (i.c.) spaces. This pattern needs to be distinguished from similar ECG changes due to other causes (“Brugada ECG phenocopies”). This review focuses mainly on the ECG-based methods for diagnosis and arrhythmia risk assessment in the BrS. Presently the main unresolved clinical problem is the identification of those patients at high risk of SCD who need implantable cardioverter-defibrillator (ICD) which is the only therapy with proven efficacy. Current guidelines recommend ICD implantation only in patients with spontaneous type 1 ECG pattern and either history of aborted cardiac arrest or documented sustained VT (class I) or syncope of arrhythmic origin (class IIa) because they are at high risk of recurrent arrhythmic events (up to 10% or more annually for those with aborted cardiac arrest). The majority of BrS patients are asymptomatic when diagnosed and considered to have low risk (around 0.5% annually) and therefore not indicated for ICD. The majority of SCD victims in the BrS, however, have had no symptoms prior to the fatal event and therefore were not protected with an ICD. While some ECG markers such as QRS fragmentation, infero-lateral early repolarisation, abnormal late potentials on signal-averaged ECG are known to be linked to increased arrhythmic risk they are not sufficiently sensitive or specific. Potential novel ECG-based strategies for risk stratification are discussed based on computerised methods for depolarisation and repolarisation analysis, a composite approach targeting several major components of ventricular arrhythmogenesis and the collection of large digital ECG databases in genotyped BrS patients and their relatives.
    Journal of the Saudi Heart Association 07/2014;