Sign in →

Test ID BRGGP Brugada Syndrome Multi-Gene Panel, Blood

Useful For

Providing a genetic evaluation for patients with a personal or family history suggestive of Brugada syndrome

 

Establishing a diagnosis of a Brugada syndrome, in some cases, allowing for appropriate management and surveillance for disease features based on the gene involved

 

Identifying variants within genes known to be associated with increased risk for disease features and allowing for predictive testing of at-risk family members

Method Name

Custom Sequence Capture and Targeted Next Generation Sequencing followed by Polymerase Chain Reaction (PCR) and Supplemental Sanger Sequencing

Reporting Name

Brugada Syndrome Multi-Gene Panel,B

Specimen Type

Whole Blood EDTA

Container/Tube: Lavender top (EDTA)

Specimen Volume: 3 mL

Collection Instructions: Send specimen in original tube.

Additional Information:

1. Include physician name and phone number with the specimen.

2. Prior Authorization is available for this test. Submit the required form with the specimen.

Forms:

1. Hereditary Cardiomyopathies and Arrhythmias: Patient Information Sheet (T725) is required. See Special Instructions.

2. New York Clients-Informed consent is required. Please document on the request form or electronic order that a copy is on file. An Informed Consent for Genetic Testing (T576) is available in Special Instructions.

3. Brugada Syndrome Multi-Gene Panel Prior Authorization Ordering Instructions in Special Instructions

4. If not ordering electronically, complete, print, and send a Cardiovascular Test Request Form (T724) with the specimen (http://www.mayomedicallaboratories.com/it-mmfiles/cardiovascular-request-form.pdf).

Specimen Minimum Volume

0.6 mL

Specimen Stability Information

Specimen Type Temperature Time
Whole Blood EDTA Ambient (preferred)
  Refrigerated 

Clinical Information

Brugada syndrome (BrS) is a genetic cardiac disorder characterized by ST segment elevation in leads V1-V3 on electrocardiography (EKG) with a high risk for ventricular arrhythmias that can lead to sudden cardiac death. BrS is inherited in an autosomal dominant manner and is caused by pathogenic variants in genes that encode cardiac ion channels. The diagnosis of BrS is established based on the characteristic EKG abnormality along with personal and family health history, and also requires exclusion of other causes including cardiac structural abnormalities, medications, and electrolyte imbalances.

 

BrS has also been called sudden unexplained nocturnal death syndrome (SUNDS) due to the tendency for syncope and sudden cardiac death to occur at rest or during sleep. The most common presentation of BrS is a male in his 40s with a history of syncopal episodes and malignant arrhythmias. However, presentation may occur at any age including infancy, where BrS may present as SIDS (sudden infant death syndrome). Published studies indicate that BrS is responsible for 4% to 12% of unexpected sudden deaths and for up to 20% of all sudden death in individuals with a structurally normal heart.

 

The prevalence of BrS in the general population is difficult to determine due to the challenges of diagnosing the condition. In Southeast Asia where SUNDS is endemic, the prevalence of BrS is estimated to be 1 in 2,000. Of note, men are 8 to 10 times more likely to express symptoms of BrS, but the disease affects females as well and both sexes are at risk for ventricular arrhythmia and sudden death.

 

Approximately 25% to 30% of BrS is accounted for by pathogenic variants in the genes known to cause the disorder, with the majority of cases attributed to the SCN5A gene. Although the majority of pathogenic variants identified to date have been detected by sequence analysis, large deletions in the SCN5A, SCN3B, CACNA1C, and KCNE3 genes have been reported in BrS. Genetic testing for BrS is supported by multiple consensus statements to confirm the diagnosis and identify at-risk family members. This is particularly important because the majority of patients with BrS are asymptomatic, but asymptomatic individuals may still be at increased risk for cardiac events. Pre- and post-test genetic counseling is an important factor in the diagnosis and management of BrS and is supported by expert consensus statements.

Reference Values

An interpretive report will be provided. 

Cautions

Clinical Correlations:

Some individuals who have involvement of 1 or more of the genes on the panel may have a variant that is not identified by the methods performed (eg, promoter variants, deep intronic variants). The absence of a variant, therefore, does not eliminate the possibility of Brugada syndrome or a related disorder.

                              

Test results should be interpreted in context of clinical findings, family history, and other laboratory data. Misinterpretation of results may occur if the information provided is inaccurate or incomplete.

 

If testing was performed because of a family history of Brugada syndrome or a related disorder, it is often useful to first test an affected family member. Identification of a pathogenic variant in an affected individual allows for more informative testing of at-risk individuals.

 

Technical Limitations:

Next generation sequencing may not detect all types of genetic variants. Additionally, rare polymorphisms may be present that could lead to false-negative or false-positive results. If results do not match clinical findings, consider alternative methods for analyzing these genes, such as Sanger sequencing or large deletion/duplication analysis. If the patient has had an allogeneic blood or marrow transplant or a recent (ie, less than 6 weeks from time of sample collection) heterologous blood transfusion, results may be inaccurate due to the presence of donor DNA.

 

Reclassification of Variants Policy:

At this time, it is not standard practice for the laboratory to systematically review likely pathogenic variants or variants of uncertain significance that are detected and reported. The laboratory encourages health care providers to contact the laboratory at any time to learn how the status of a particular variant may have changed over time.

 

Contact the laboratory if additional information is required regarding the transcript or human genome assembly used for the analysis of this patient’s results.

Day(s) Performed

Wednesday; Varies

Report Available

4 weeks after prior authorization approved

Performing Laboratory

Mayo Medical Laboratories in Rochester

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information

81479 CACNA1C, CACNA2D1, GPD1L, KCNE3, KCNJ8, and SCN3B

81406 CACNB2

81404 SCN1B

81407 SCN5A

NY State Approved

Conditional

Prior Authorization

Insurance preauthorization is available for this testing; forms are available in Special Instructions.

 

Patient financial assistance may be available to those who qualify. Patients who receive a bill from Mayo Medical Laboratories will receive information on eligibility and how to apply.