Fragmented QRS as a Marker of Conduction Abnormality and a Predictor of Prognosis of Brugada Syndrome

Morita, Hiroshi; Kusano, Kengo; Miura, Daiji; Nagase, Satoshi; Nakamura, Kazufumi; Morita, Shiho; Ohe, Tohru; Zipes, Douglas P.; Wu, Jiashin

doi:10.1161/circulationaha.108.770917

Cited by 416 publications

(313 citation statements)

References 29 publications

Supporting

Mentioning

294

Contrasting

Unclassified

Order By: Relevance

“…[2][3][4][5][6][7][8] Mutations in SCN5A, which encodes the pore-forming subunit of the cardiac voltage-gated sodium channel, have been associated with the major form of BrS (BrS1) in approximately 20% of cases. [9][10][11] The clinical severity of BrS may vary with the responsible genes and/or mutation sites, although the genotypephenotype relationship remains poorly characterized. The presence of SCN5A mutations is not related to the severity of the disease.…”

Section: Discussionmentioning

confidence: 99%

Identification of Six Novel SCN5A Mutations in Japanese Patients With Brugada Syndrome

et al. 2011

View full text Add to dashboard Cite

SummaryMutations in SCN5A are linked to Brugada syndrome in approximately 20% of all cases (BrS1). Several dozen distinct SCN5A mutations in BrS1 have been associated with the increased risk of cardiac arrhythmias. However, the genotype-phenotype relationship remains elusive. The current study analyzed the SCN5A gene to elucidate the potential variability of clinical features in Japanese BrS1 subjects. Subjects of the present study included 30 probands (25 male subjects, 45 ± 15 years of age) with Brugada-pattern ECG. Seven patients had been resuscitated from cardiopulmonary arrest (CPA group). Another 10 patients had a history of syncope (Sy group), and 13 more remain asymptomatic (Asy group). We identified 8 different SCN5A mutations, including 6 novel mutations (CPA group: 1/7, Sy group: 3/10, Asy group: 4/13). An A735E mutation (located at segment (S)1 in domain (D)2) was identified in the CPA group. A novel splice acceptor site mutation (c.393-1c>t), which may produce a prematurely truncated protein, was identified in the Sy group. An E1784K mutation (C-terminus) and a novel mutation V1951M (C-terminus) were also identified in the Sy group. Four novel missense mutations, A586T (D1-D2 linker), R689H (D1-D2 linker), S1553R (S1-S2 in D4), and Q1706H (S5-Pore in D4) were identified in the Asy group. These data may help us understand the genetic heterogeneity of BrS1, which is more prevalent in Japanese than in whites and other ethnic groups. (Int Heart J 2011; 52: 27-31) Key words: Brugada syndrome, SCN5A, Mutation T he Brugada syndrome (BrS), characterized by ST-segment elevations in the right precordial ECG leads without structural heart disease, is a hereditable disease associated with an increased risk of sudden death due to polymorphic ventricular tachycardia or ventricular fibrillation (VF).1) Genetic analyses of BrS revealed that BrS is genetically heterogeneous, and is linked to at least 7 different genes. [2][3][4][5][6][7][8] Mutations in SCN5A, which encodes the pore-forming subunit of the cardiac voltage-gated sodium channel, have been associated with the major form of BrS (BrS1) in approximately 20% of cases. [9][10][11] The clinical severity of BrS may vary with the responsible genes and/or mutation sites, although the genotypephenotype relationship remains poorly characterized. The presence of SCN5A mutations is not related to the severity of the disease.9,10,12) However, Meregalli, et al have recently reported that the type of SCN5A mutation in BrS1 in European countries may determine the clinical severity.13) Because the clinical features of BrS vary among different ethnicities, 14,15) it is of great value to investigate the genotype-phenotype relationship of BrS in Asians in whom the ratio of BrS patients is relatively high compared to subjects from different ethnic backgrounds.In the present study, we analyzed the SCN5A gene to elucidate the potential variability of clinical features of BrS1 subjects recruited from Gunma University Hospital. Consequently, we identified 8 SCN5A mutations, incl...

show abstract

Section: Discussionmentioning

confidence: 99%

Identification of Six Novel SCN5A Mutations in Japanese Patients With Brugada Syndrome

et al. 2011

View full text Add to dashboard Cite

show abstract

“…marker of depolarization abnormality and myocardial scar in patients with coronary artery disease (Varriale and Chryssos 1992;Das et al 2006;Michael et al 2007;Das et al 2009). Additionally, fQRS has been demonstrated as a marker of increased mortality and arrhythmic events in patients with ischemic cardiomyopathy ), arrhythmogenic right ventricular dysplasia/cardiomyopathy (Peters et al 2008) and Brugada syndrome (Morita et al 2008). More importantly, it has been shown that the presence of fQRS in ≥2 contiguous leads predicts myocardial scar in patients with coronary artery disease.…”

Section: Discussionmentioning

confidence: 99%

Fragmented QRS Is Predictive of Myocardial Dysfunction, Pulmonary Hypertension and Severity in Mitral Stenosis

Yüce

Davutoğlu

Ozbala

et al. 2010

Tohoku J. Exp. Med.

View full text Add to dashboard Cite

“…A recent report showed that such fractionated QRS may have some relationship with their arrhythmic events in patients with type 1 ECG (Morita et al 2008). Other study also showed that right ventricular conduction is delayed in patients with Brugada syndrome (Tukkie et al 2004).…”

Section: Late Potentials By Sa-ecgmentioning

confidence: 95%

“…patients with type 1 ECG could show fractionated QRS as a result of conduction abnormality (Morita et al 2008). A recent report showed that such fractionated QRS may have some relationship with their arrhythmic events in patients with type 1 ECG (Morita et al 2008).…”

Section: Late Potentials By Sa-ecgmentioning

confidence: 99%

Prognostic Significance of Late Potentials in Outpatients with Type 2 Brugada Electrocardiogram

Fukuda

Kondo

Segawa

et al. 2016

Tohoku J. Exp. Med.

View full text Add to dashboard Cite

Brugada syndrome is characterized by distinguishing electrocardiogram (ECG) patterns (coved and saddleback types with day-to-day variation) and occurrence of lethal tachy-arrhythmias. The appearance of coved type ECG (type 1) is required for the diagnosis of Brugada syndrome, whereas the significance of saddleback type ECG (type 2), which is inadequate for the diagnosis, has not been fully established. We enrolled 34 consecutive patients with type 2 ECG on outpatient-clinic. Among them, 7 patients were ventricular fibrillation (VF) survivors who were diagnosed as Brugada syndrome with transient appearance of type 1 ECG, and showed type 2 ECG on their first outpatient-clinic visit after the VF event (VF group). The remaining 27 were asymptomatic and never showed type 1 ECG on repeated ECG examinations (control group). The VF group showed significantly longer RJ intervals in leads V1 and V2 and QTc intervals in lead V2 compared with the control group (P < 0.030, P < 0.017, and P < 0.030, respectively). Late potentials, detected on the signal-averaged ECG (SA-ECG), reflect conduction abnormalities and are known as one of the risk markers of arrhythmic events. Among the 34 patients, late potentials were negative in 12 patients belonging to the control group. In conclusion, the SA-ECG could be helpful to identify high-risk patients for its high negative predictive value as the first step, and ECG parameters, including RJ intervals in leads V1 and V2 and QTc interval in lead V2, could be useful for further risk stratification in patients with type 2 Brugada ECG.

show abstract

Fragmented QRS as a Marker of Conduction Abnormality and a Predictor of Prognosis of Brugada Syndrome

Cited by 416 publications

References 29 publications

Identification of Six Novel SCN5A Mutations in Japanese Patients With Brugada Syndrome

Identification of Six Novel SCN5A Mutations in Japanese Patients With Brugada Syndrome

Fragmented QRS Is Predictive of Myocardial Dysfunction, Pulmonary Hypertension and Severity in Mitral Stenosis

Prognostic Significance of Late Potentials in Outpatients with Type 2 Brugada Electrocardiogram

Contact Info

Product

Resources

About