Dataset Information

Relations between right ventricular morphology and clinical, electrical and genetic parameters in Brugada Syndrome.

ABSTRACT:

Background

Increasing evidence suggests the presence of structural changes affecting the right ventricular outflow tract (RVOT) in patients with Brugada Syndrome (BrS). The aim of this study was to characterise the RV morphology in BrS and explore associations between morphologic, clinical, electrical, and genetic parameters using non-invasive multimodality testing.

Methods

Consecutive BrS patients (recruited 2013-2015) underwent clinical assessment, dedicated RV imaging using cardiac magnetic resonance (CMR) imaging (unless contra-indicated), electrical assessment (electrocardiogram, Holter monitoring, signal-averaged ECG[SAECG]) and genotyping. Morphologic data were compared to matched control and unmatched ARVC (arrhythmogenic right ventricular cardiomyopathy) cohorts, and potential associations between morphologic parameters and other variables were explored.

Results

BrS patients (n = 42, male 86%, age 46±12 years) exhibited normal global RV volume and function, comparable to control, in contrast to significantly larger, impaired RVs in ARVC cohort (RVESV p = 0.0001; RVEDV p<0.0001, RVEF p = 0.002). Compared with control, BrS patients exhibited larger RVOT volumes (7.4 ± 0.7 vs 5.8 ± 0.7 mL/m2, p<0.0001) and wall motion abnormalities (RWMA) (31% vs 0%, p = 0.005); compared with ARVC cohort, the RVOT volumes were similar (7.4 ± 0.7 vs, 8.1 ± 1.7, p = 0.52) and there were less RWMA (31% vs 76%, p = 0.01). Overall 67% BrS patients had abnormal RVOT morphology. Patients with abnormal RVOT tended to be older (48 ± 12 y vs 41 ± 12y, p = 0.06). Rare genetic variants were only observed in patients with abnormal RVOT morphology (36% vs 0%, p = 0.02).

Conclusions

Patients with BrS frequently exhibit structural abnormalities localised to the RVOT and these changes may be age- and gene-dependent.

SUBMITTER: Gray B

PROVIDER: S-EPMC5898761 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Relations between right ventricular morphology and clinical, electrical and genetic parameters in Brugada Syndrome.

Gray Belinda B Gray Belinda B Gnanappa Ganesh Kumar GK Bagnall Richard D RD Femia Giuseppe G Yeates Laura L Ingles Jodie J Burns Charlotte C Puranik Rajesh R Grieve Stuart M SM Semsarian Christopher C Sy Raymond W RW

PloS one 20180413 4

<h4>Background</h4>Increasing evidence suggests the presence of structural changes affecting the right ventricular outflow tract (RVOT) in patients with Brugada Syndrome (BrS). The aim of this study was to characterise the RV morphology in BrS and explore associations between morphologic, clinical, electrical, and genetic parameters using non-invasive multimodality testing.<h4>Methods</h4>Consecutive BrS patients (recruited 2013-2015) underwent clinical assessment, dedicated RV imaging using car ...[more]

PMID: 29652902

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Project description:Brugada syndrome (BS) is a genetic pathological condition associated with a high risk for sudden cardiac death (SCD). Ventricular depolarization disorders have been suggested as a potential electrophysiological mechanism associated with high SCD risk on patients with BS. This paper aims to characterize the dynamic changes of ventricular depolarization observed during physical exercise in symptomatic and asymptomatic BS patients. To this end, cardiac ventricular depolarization features were automatically extracted from 12-lead ECG recordings acquired during standardized exercise stress test in 110 BS patients, of whom 25 were symptomatic. Conventional parameters were evaluated, including QRS duration, R and S wave amplitudes ([Formula: see text], [Formula: see text]), as well as QRS morphological features, such as up-stroke and down-stroke slopes of the R and S waves ([Formula: see text], [Formula: see text] and [Formula: see text]). The effects of physical exercise and recovery on the dynamics of these markers were assessed in both BS populations. Features showing significantly different dynamics between the studied groups were used alone and in combination with the clinical characteristics of the patients in a logistic regression analysis. Results show larger changes in the second half of the QRS complex through [Formula: see text] and [Formula: see text] measured in the right precordial leads for asymptomatic patients, especially during recovery, when the vagal tone is more pronounced. Multivariate analysis involving both types of features resulted in a reduced model of three relevant features ([Formula: see text] in lead V2, Sex and heart rate recovery, HRR), which achieved a suitable discrimination performance between groups; sensitivity = 80% and specificity = 75% (AUC = 83%). However, after controlling the model for possible confounding factors, only one feature ([Formula: see text]) remained meaningful. This adjusted model significantly improved the overall discrimination performance by up to: sensitivity = 84% and specificity = 100% (AUC = 94%). The study highlights the importance of physical exercise test to unmask differentiated behaviors between symptomatic and asymptomatic BS patients through depolarization dynamic analysis. This analysis together with the obtained model may help to identify asymptomatic patients at low or high risk of future cardiac events, but it should be confirmed by further prospective studies.

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Dataset Information

Relations between right ventricular morphology and clinical, electrical and genetic parameters in Brugada Syndrome.

Background

Methods

Results

Conclusions

Publications

Relations between right ventricular morphology and clinical, electrical and genetic parameters in Brugada Syndrome.

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