A study at the University of Amsterdam recently published in the Journal of Pediatrics found that most kids carrying a gene for HCM will not go on to develop HCM during their childhood.
The same study also found that gene positive children without overt signs of the disease are at relatively low risk for cardiac events.
The study included 119 children, positive for at least one HCM gene, with a median age of 12.1 years. 8 of these children (6.7%) received a HCM diagnosis within the time span of the study [which varied from 3.1 to 10.7 years]. 1 of the 8 diagnosed children suffered a cardiac event which necessitated implantation of an implantable cardioverter defibrillator or ICD.
The study did caution, however, that because severe hypertrophy and cardiac events may develop, it is important to refine risk stratification and long term follow up procedures for gene positive kids.
A recent study followed 14 patients carrying one of two known genes associated with HCM (MYBPC3 and MYH7) over a 10+ year period . At the time of gene identification, none of the patients shown clinical evidence of hypertrophy. Over the time span of the study, 3 patients, who were then adults, had developed signs of HCM. Hence, the study suggests that periodic screenings are necessary for gene positive individuals throughout adulthood.
According to Cardiomyopathy U.K., the researchers undertook this project due to the lack of information and guidelines available to patients who are gene positive but have no outward signs of the disease.