Cardiomyopathy genetic testing: insights into demographics, counseling, and cascade screening

Genetic testing (GT) is clinically indicated for patients with suspected inherited cardiomyopathy (CM) but is underutilized. This single-center study included patients with CM who underwent outpatient GT from 2018 to 2023. Data were collected from the medical record. A total of 306 patients were included, with a mean age of 62 years and were predominantly male (63%) and White (59%). Heart failure (92%) cardiologists were most likely to order testing, followed by general cardiology (5%) providers at tertiary hospital clinics (89%). The most common phenotypes were hypertrophic (30%), amyloid (29%) and dilated (21%). There were 17% of patients who had a positive test and 53% of patients who had a variant of uncertain significance. Patients with a positive family history had a significantly higher positive yield compared to those without (p Outpatient GT for CM was primarily ordered by heart failure cardiologists in tertiary hospital clinics. Cascade screening was low, which may reflect the limited use of genetic counselors. Further research is needed to understand implementation barriers to GT. We studied how genetic testing is used in patients with a heart muscle disorder to understand barriers that may limit its use. Our study included 306 patients who had outpatient genetic testing between 2018 and 2023. We found that heart failure cardiologists ordered most of the tests, while general cardiologists and electrophysiologists ordered fewer. Genetic testing was less common in clinics that care for underserved communities. Additionally, family screening with genetic testing was infrequent, possibly due to limited referrals to genetic counselors. These findings highlight key barriers to genetic testing and can help guide strategies to improve use.