HCM Family Screening Protocol — EECC MCQ

Correct answer: C — Clinical screening with ECG and echocardiography starting at age 10-12 years, repeated every 1-2 years during adolescence; genetic testing of the proband first, then cascade genetic testing of relatives if a pathogenic variant is identified

HCM is an autosomal dominant condition with variable penetrance and expressivity. The 2023 ESC Cardiomyopathy Guidelines recommend: (1) Genetic testing of the proband (affected family member) first to identify the causative variant; (2) If a pathogenic variant is found: cascade predictive genetic testing of first-degree relatives — gene-positive individuals undergo clinical screening (ECG + echo); gene-negative individuals can be discharged; (3) If genetic testing is negative or inconclusive: clinical screening of all first-degree relatives with ECG and echo starting at age 10-12 years, repeated every 1-2 years during adolescence (when penetrance increases rapidly) and every 2-5 years in adulthood; (4) Earlier screening if the child is involved in competitive sport. HCM may not manifest phenotypically until adolescence due to the effects of growth and hormonal changes.

Reference: ESC (2023): Guidelines on Cardiomyopathies