Evaluation of Clinical Practices and Needs about Variants of Uncertain Significance Results in Inherited Cardiac Arrhythmia and Inherited Cardiomyopathy Genes

The increasing numbers of genetic tests in clinical settings have identified many variants of uncertain significance (VUS) in genes associated with inherited cardiac arrhythmias and inherited cardiomyopathies. Evaluation of clinical practices including counseling strategies and medical management recommendations for patients and their families is important to improve patient outcomes and prevent over- or under-treatment that may result in morbidity or fatality. The purpose of this study is to describe provider practices related to VUS results including how they conduct risk assessments and ascertain what information and medical management recommendations they provide to patients with VUS results and the patients’ family members. Additionally, we aim to describe providers’ concerns and informational needs related to counseling about a VUS. An anonymous online survey was developed for the current study and distributed to genetic counselors through the National Society of Genetic Counselors (NSGC) listerv and to cardiologists via emails obtained from publicly available resources. The survey explored healthcare providers’ confidence in counseling about a VUS, explanation of a VUS to patients, topics covered before and after genetic testing, and recommendations for patients with a VUS and their families using clinical vignettes. Providers (N=102) who completed the survey included 29 cardiovascular genetic counselors, 50 genetic counselors from other specialties, and 23 cardiologists. A hypothetical clinical scenario was used in which a young adult patient had a VUS in a gene causing Arrhythmogenic Right Ventricular Cardiomyopathy, but did not meet clinical diagnostic criteria for the condition. The patient’s only concerning issues included a personal history of fainting during exercising and sudden death of a 45 year old first-degree relative. Nearly 9% of all providers incorrectly described the VUS as likely pathogenic, while 15% would downplay the finding by indicating the VUS is more likely to eventually be reclassified as benign. Genetic counselors feel more confident about counseling about VUS results (p\u3c0.001). Both cardiovascular genetic counselors and cardiologists feel confident in making medical management recommendations; however, cardiologists are more likely to recommend treatment with beta-blockers and exercise limitation for the patient. Compared to cardiac genetic counselors, other genetic counselors (p=0.001) and cardiologists (p=0.014) were more likely to recommend clinical testing for family members even though testing is expected to be uninformative, especially given the absence of any clinical diagnosis in the family. These findings highlight the expertise of different providers in different specialty area and suggest the need for interdisciplinary clinics that include cardiologists, cardiac genetic counselors, nurses, geneticists, psychologists and others to optimize care for challenging cases where VUS results create uncertainty