CurrentCapital BluecrossPolicy MP 2.328

Genetic Testing for Idiopathic Dilated Cardiomyopathy

Defines medical necessity and investigational uses of genetic testing for individuals with dilated cardiomyopathy (DCM) or at-risk relatives, describes standard workup for idiopathic DCM, coding guidance, and references. Applies to products administered by Capital Blue Cross with benefit variations.

Policy Summary

PayerCapital Bluecross

PolicyGenetic Testing for Idiopathic Dilated Cardiomyopathy

Policy CodePolicy MP 2.328

Change TypeConsensus review — references updated

Effective DateJul 1, 2025

Next Review Date

Key ActionDocument that DCM is idiopathic after a negative workup for secondary causes for comprehensive testing; confirm a known familial variant when ordering targeted testing for asymptomatic first-degree relatives.

POLICY UPDATE CHANGES

02/21/2025 Consensus Review: No change to policy statement; references updated.

2Medically Necessary Indications

1Investigational/Not Covered

6Listed CPT Codes

Coverage Summary

This policy defines medical necessity and investigational uses for genetic testing related to dilated cardiomyopathy (DCM). Specifically, comprehensive genetic testing is considered medically necessary for individuals with signs or symptoms of DCM that is idiopathic after a negative workup for secondary causes, and targeted genetic testing is considered medically necessary for asymptomatic first-degree relatives when there is a known familial variant in the affected relative. Genetic testing in all other situations is considered investigational and not medically necessary.

Medical-Necessity Criteria

Medically necessary - Comprehensive testing in symptomatic individuals

Comprehensive genetic testing is considered medically necessary when ALL of the following are met:

ALL of the following

Symptomatic DCM: Individual has signs or symptoms of dilated cardiomyopathy (DCM).
Idiopathic after negative workup: DCM is considered idiopathic after a negative workup for secondary causes.
Standard workup includes clinical exam, blood pressure monitoring, electrocardiography, echocardiography, and coronary artery disease workup as warranted by risk factors; an extensive workup (cardiac MRI, exercise testing, right-sided catheterization with biopsy, 24-hour ECG) uncovers few additional etiologies.

Medically necessary - Targeted testing in asymptomatic at-risk relatives

Targeted genetic testing is considered medically necessary when ALL of the following are met:

ALL of the following

Asymptomatic: Individual is asymptomatic.
First-degree relative: Individual is a first-degree relative of a person with dilated cardiomyopathy.
Known familial variant: There is a known familial variant identified in the affected relative.
Testing is targeted to the known familial variant.

Investigational / Not medically necessary

Genetic testing for dilated cardiomyopathy is considered investigational when ANY of the following apply:

Investigational uses: Testing is performed in situations other than the two medically necessary scenarios above (comprehensive testing in symptomatic idiopathic DCM and targeted testing for asymptomatic first-degree relatives with a known familial variant).

Provider Actions & Billing Guidance

Documentation Required

Document negative workup for secondary causes

For comprehensive testing in symptomatic individuals, document that DCM is idiopathic after a negative workup for secondary causes. The standard workup includes a clinical exam, blood pressure monitoring, electrocardiography (ECG), echocardiography, and evaluation for coronary artery disease as warranted by risk factors.

Clinical exam
Blood pressure monitoring
Electrocardiography (ECG)
Echocardiography
Workup for coronary artery disease as warranted by risk factors

Documentation Required

Confirm familial variant for targeted testing

For targeted testing of asymptomatic first-degree relatives, document that there is a known familial variant identified in the affected relative and that testing will be targeted to that variant.

Prior Authorization

Benefit verification required

The existence of this medical policy does not guarantee coverage. Providers should consult the member's applicable health benefit plan for coverage details and contact Capital Blue Cross for benefit information or questions about application to a specific member's plan.

Billing Rule

Coding guidance advisory

The listed CPT procedure codes may be used to report genetic testing for cardiomyopathy, but identification of a code in the policy does not denote coverage. Reimbursement and coverage are determined by the member's benefit plan and coding review.

81403
81405
81406
81407
81439
81479

Background & Evidence

Dilated cardiomyopathy (DCM) is characterized by progressive left ventricular enlargement and systolic dysfunction, producing clinical manifestations of heart failure and arrhythmias. When secondary causes are excluded by the standard workup (clinical exam, blood pressure monitoring, electrocardiography, echocardiography, and coronary artery disease evaluation as warranted), approximately 35% to 40% of DCM cases are determined to be idiopathic (idiopathic dilated cardiomyopathy or IDC).

Genetic testing of idiopathic DCM cases identifies disease-associated variants in approximately 10% to 40% of tested individuals (overall detection ~30%–40% in referred cohorts), with disease-associated variants reported in more than 40 genes. The most commonly implicated genes include TTN, MYH7, TNNT2, and TPM1, which together account for about 30% of identified disease-associated variants.

Fact	Value
Variant detection rate in idiopathic DCM	10% to 40%
Proportion of DCM cases considered idiopathic after standard workup	35% to 40%
Genes commonly implicated	TTN, MYH7, TNNT2, TPM1 (~30% of identified variants)

Idiopathic dilated cardiomyopathy (IDC): DCM determined after a negative workup for secondary causes including clinical exam, blood pressure monitoring, electrocardiography, echocardiography, and coronary artery disease evaluation as warranted.

Familial variant: disease-associated variant identified in a proband for use in subsequent targeted genetic testing in first-degree relatives.

Revision History

03/13/2020consensus_review

Consensus Review: No change to policy statement; references updated; coding reviewed.

04/15/2021consensus_review

Consensus Review: No change to policy statements; references updated; coding reviewed.

03/16/2022consensus_review

Consensus Review: Policy statement unchanged; FEP language updated; references added.

03/07/2023consensus_review

Consensus Review: No change to policy statement; background, rationale, and references updated.

03/12/2024consensus_review

Consensus Review: No change to policy statement; references added.

02/21/2025consensus_reviewLatest

No change to policy statement; references updated