The Impact of Integration of a Genetic Clinic Into a Pediatric Cardiac Unit.

Background: Previously published studies suggest that genetic or environmental causes can be observed in 20-30% of congenital heart disease (CHD) patients, which include aneuploidy, single gene defects, pathological copy number variations, and de novo autosomal dominant and recessive inheritance. Moreover, the genetic background of childhood cardiomyopathies (CMs) has not been elucidated well.

Objective: The study highlights the value of genetic assessment in diagnosing and family counseling for CHD and pediatric CM patients referred to the genetic clinic in a pediatric cardiology department.

Methods: The study involved patients less than 18 years of age attending the cardiogenetic clinic in the pediatric cardiology department between December 2010 and February 2019. The following patient categories who had genetic evaluation were included: CHD in the presence of a syndromic phenotype, patients with CHD having extracardiac congenital anomalies or delayed development, hypertrophic and dilated CM patients, patients with dilated aortic root and ascending aorta, significant CHD in siblings or first-degree relatives, suspected channelopathies; and interrupted aortic arch abnormalities.

Results: A total of 285 patients were evaluated in the cardiogenetic clinic. The mean age was 20.2 months, with a range of 0-168. Females and males constituted 153 (53.7%) and 132 (46.3%), respectively. The most common cause of referral to the genetic clinic was the presence of CM (N=134 (46.3%)): hypertrophic CM in 24% and dilated CM in 20% of cases. Seventy-six patients (26.7%) had positive genetic results. The most common genetic abnormality was familial infantile hypertrophic CM-causing gene in 19 (23.5%) cases.

Conclusion: It may be beneficial for any pediatric cardiology unit to provide an established genetic clinic. Using a genetic clinic will enhance understanding of CHD pathophysiology, family education, and genetic counseling. Agreement on a well-written protocol and the way forward to specify what congenital heart conditions require genetic investigation should be clarified.