The Role of the Genetic Counselor in Patients with Heart Rhythm Disorders

Heather MacLeod, MS CGC
Genetic Counselor, Cardiac Team Leader, InformedDNA
St. Petersburg, Florida

Heather MacLeod, MS CGC
Genetic Counselor, Cardiac Team Leader, InformedDNA
St. Petersburg, Florida

Introduction

Genetic counselors play an important role in assuring comprehensive cardiac care to patients with heart rhythm disorders. Many of the diagnoses seen in electrophysiology clinics have a genetic component, and therefore appropriate work-up by a trained genetics specialist can assist both in diagnosis and management of patients. The purpose of this article is to outline the role of genetic counselors in heart rhythm disorders and provide useful information on how your patients can easily access genetic counseling services. 

Who are Genetic Counselors?

Genetic counselors are health professionals with specialized graduate degrees and experience in the areas of medical genetics and counseling. The National Society of Genetic Counselors estimates there are approximately 2,700 genetic counselors working in the United States.1 The majority specialize in cancer and reproductive genetic counseling; a small but growing number specialize in cardiovascular disease. Genetic counselors work in a variety of settings including university medical centers, community hospitals, and laboratories. 

When to/Why Refer?

National guidelines2,3 recommend that patients be referred for genetic counseling when a cardiac diagnosis with a genetic component (Table 1) is known or suspected in the family.

Additionally, patients should be referred if they have a personal or family history of:

  • Multiple family members with the same type of heart disease
  • Coronary artery disease in ≥2 first- or second-degree relatives where the age at diagnosis is <55 years old in a male or <65 years old in a female
  • Congenital heart disease
  • Familial thoracic aneurysm
  • Sudden cardiac death or unexplained death in patients <50 years old
  • Cardiac device (e.g., pacemaker or defibrillator) or heart transplant in patients <50 years old

The availability of recently published guidelines makes it even more imperative to identify and refer appropriate patients for genetics evaluation for a growing number of cardiac conditions. Due to the potential implications of genetic testing, health plan policies are more frequently requiring pre- and post-test genetic counseling by a trained genetics professional as a condition for coverage of genetic tests.4

The Genetic Counseling Process

A thorough genetics evaluation involves several components:

Family History and Risk Assessment

To optimize the sensitivity of a risk assessment, genetic counselors construct a pedigree including at least three generations, structuring the interview to efficiently elicit the clues that affect risk assessment (Table 2). This detective work includes gleaning additional information about events in the family history that can seem unrelated to heart disease (e.g., car accidents or drownings). For example, knowing a relative drove off the road on a clear temperate day with no other cars around and is found dead in their car, versus knowing that a family member died in a head-on collision during a blizzard, can change the assessment regarding likelihood of an inherited arrhythmia syndrome. The process of collecting and discussing family history often facilitates patient education by allowing the genetic counselor to develop rapport with the patient, as well as to learn about family dynamics and potential barriers to obtaining complete medical information or other psychosocial issues. The pedigree is also a useful tool in explaining inheritance and identifying at-risk relatives who need screening.

In addition to the pedigree, medical records are gathered to verify diagnoses in relatives with suspicious cardiac histories. In many cardiac family histories, autopsy reports are also collected to confirm the cause of death and verify if there are cardiac findings associated with the patient’s diagnosis. The genetic counselor uses this information to uncover patterns of inheritance, reduced penetrance, or other features consistent with a hereditary syndrome. Collection and assessment of family history ends up being the oldest and least expensive genetic test available.

Genetic Testing

Cardiovascular genetic testing has greatly expanded in the last eight years. Testing is primarily offered in large multi-gene panels based on phenotype (e.g., long QT panel for 12–13 genes5–7). This testing has evolved into more broad-based testing, including more general testing for all cardiomyopathy genes (51–56 genes5,8) and all arrhythmia genes (29 genes5) as well as a panel for 79 cardiac genes.5 Multiple labs offer clinical genetic testing for cardiovascular disease, and new options emerge regularly.

Genetic counselors are experts in the nuances of which tests and testing platforms are available, and they recommend the most appropriate testing based on the diagnosis of concern and insurance coverage. They also routinely support patients and ordering providers with completion of test requisitions, insurance prior authorization, letters of medical necessity, and other needs during the testing process.

Education, Counseling, and Informed Consent

A key outcome of genetic counseling is increased patient knowledge about the disease, the benefits and limitations of testing, and management options. Patient understanding is critical for informed consent, compliance with management once a diagnosis is made, and communication of risk to relatives. In addition to educating patients, genetic counselors are trained to simultaneously explore how disease or risk may impact other facets of patients’ lives, including relationships, self image, or life choices and planning.

Informed consent for genetic testing encompasses multiple issues beyond the test being performed and the diagnostic yield. Medical management issues, risks to family members, and the potential psychological reactions to positive and negative results should be discussed prior to ordering genetic testing. In addition, review of what the Genetic Information Nondiscrimination Act (GINA) does and doesn’t protect is necessary. Due to the risk of arrhythmia associated with many of these diagnoses, a positive genetic test result can have implications for employment (e.g., bus driver, airline pilot) in individuals without a clinical diagnosis (family-specific testing) undergoing testing, and this information needs to be reviewed prior to testing.9 Finally, options for risk estimation and management without genetic testing should be reviewed.

It is important to communicate to patients that genetic counseling does not equal genetic testing, and that they are not required to pursue testing if they elect to pursue a clinical genetics evaluation. Once informed, patients may choose not to pursue genetic testing for various reasons. Additionally, there are some barriers to ensuring that genetic testing will be informative in a given situation, including instances where an appropriate (affected) relative is not available for testing (e.g., deceased or unwilling). Lack or degree of insurance coverage can also factor into patient decisions about genetic testing, but this is becoming less of an issue as cardiac genetic testing becomes part of routine care.

Results Disclosure

Since negative test results do not rule out hereditary disease and testing often yields results with unknown clinical significance, cardiac genetics expertise is essential for result interpretation. Based on a patient’s results, genetic counselors review medical management recommendations based on current guidelines, including, for example, providing the patient with information about drugs to avoid (e.g., long QT and Brugada drug lists). Challenges in interpretation of results arise due to larger panels and newly identified rare genes moving quickly into clinical testing; variants of uncertain significance are a possibility and require careful counseling.10 Other complexities include individuals with more than one mutation, proceeding to duplication/deletion testing, and genetic testing in children.

Genetic counselors serve as a support to their patients in adjustment to their results. In families where there has been a cardiac event or sudden death, positive genetic test results can bring back feelings of grief and sadness or increase anxiety in patients. Genetic counselors are knowledgeable about supportive resources for their patients, including mental health specialists and advocacy groups.

Information for At-Risk Family Members

In addition to obtaining an accurate diagnosis and screening plan for your patients, it is important to identify other family members who may be at risk for sudden cardiac death. There is an ethical duty to warn these relatives, and from a public health perspective, data is emerging that supports the cost-effectiveness of testing at-risk family members in some scenarios.11 Genetic counselors can arm patients with tools such as a family letter to help inform at-risk relatives of the possibility of having an inherited cardiovascular disease. 

Conclusion

National guidelines support incorporating genetics risk assessment and referral into cardiology practice, but genetic counseling is a process that requires expertise and time. Resources are available.

How Do You Find a Genetic Counselor?

Providers and patients may search for a local cardiac genetic counselor at www.nsgc.org, and a map of cardiac genetic counselors is available at http://goo.gl/maps/Pymt. Clinical cardiac genetic counseling is also available for patients and families nationwide via phone or web through InformedDNA (www.informedDNA.com or 800.975.4819).

References

  1. “2012 Professional Status Survey: Executive Summary.” National Society of Genetic Counselors. Web. 12 Sept. 2012. <http://www.nsgc.org/Portals/0/PSS/PSS%202012%20Executive%20Summary%20FINAL.pdf>.
  2. HRS/EHRA expert consensus statement on the state of genetic testing for the channelopathies and cardiomyopathies. Heart Rhythm 2011;8:1308–1339.
  3. Genetics and Cardiovascular Disease. A Policy Statement From the American Heart Association. Circulation 2012;126:142–157.
  4. “Cigna Medical Coverage Policy.” 15 Oct. 2011. Web. 12 Sept. 2012. <http://www.cigna.com/assets/docs/health-care-professionals/coverage_positions/mm_0193_coveragepositioncriteria_genetic_testing_for_long_qt_syndrome.pdf>.
  5. “Arrhythmia Panels.” Ambry Genetics. Web. 5 Sept. 2012. <http://www.ambrygen.com/tests/arrhythmia-panels>.
  6. “Long QT Genetic Testing.” GeneDx. Web. 5 Sept. 2012. <http://www.genedx.com/test-catalog/cardiology/long-qt-syndrome-and-its-genetics/>.
  7. “Long QT Syndrome (LQTS).” Transgenomic, Inc. Web. 5 Sept. 2012. <http://labs.transgenomic.com/cardiology-familion/lqts>.
  8. “Pan Cardiomyopathy Panel.” Partners HealthCare Center for Personalized Genetic Medicine (PCPGM). Web. 5 Sept. 2012. <http://pcpgm.partners.org/lmm/tests/cardiomyopathy>.
  9. Blumenthal R, et al. “Cardiovascular Advisory Panel Guidelines for the Medical Examination of Commercial Motor Vehicle Drivers.” U.S. Department Of Transportation Federal Motor Carrier Safety Administration, Oct. 2002. Web. 29 Aug. 2012. <www.fmcsa.dot.gov/documents/cardio.pdf>.
  10. Caleshu C, Day S, Rehm HL, Baxter S. Use and interpretation of genetic tests in cardiovascular genetics. Heart 2010;96:1669–1675.
  11. Perez MV, Kumarasamy NA, Owens DK, et al. Cost-effectiveness of genetic testing in family members of patients with long-QT syndrome. Circ Cardiovasc Qual Outcomes 2011;4:76–84. Epub 2010 Dec 7.