Background
The etiology of idiopathic dilated cardiomyopathy (DCM) is unknown by
definition, but its familial subtype is considered to have a genetic
component. We hypothesize that most idiopathic DCM, whether familial or
non-familial, has a genetic basis, in which case a genetics-driven approach
to identifying at-risk family members for clinical screening and early
intervention could reduce morbidity and mortality.
Methods
Based on this hypothesis, we have launched the NHLBI- and
NHGRI-funded DCM Precision Medicine Study, which aims to enroll 1,300
individuals (600 non-Hispanic African ancestry, 600 non-Hispanic European
ancestry, and 100 Hispanic) who meet rigorous clinical criteria for
idiopathic DCM along with 2,600 of their relatives. Enrolled relatives will
undergo clinical cardiovascular screening to identify asymptomatic disease,
and all individuals with idiopathic DCM will undergo exome sequencing to
identify relevant variants in genes previously implicated in DCM. Results
will be returned by genetic counselors 12-14 months after enrollment. The
data obtained will be used to describe the prevalence of familial DCM among
idiopathic DCM cases and the genetic architecture of idiopathic DCM in
multiple ethnicity-ancestry groups. We will also conduct a randomized
controlled trial to test the effectiveness of Family Heart
Talk, an intervention to aid family communication, for
improving uptake of preventive screening and surveillance in at-risk
first-degree relatives.
Conclusions
We anticipate this study will demonstrate that idiopathic DCM has a
genetic basis and guide best practices for a genetics-driven approach to
early intervention in at-risk relatives.