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β1-receptor polymorphisms and junctional ectopic tachycardia in children after cardiac surgery

Leanne Dumeny1, Marut Chantra2, Taimour Langaee1

  • 1Department of Pharmacotherapy and Translational Research, Center for Pharmacogenomics and Precision Medicine, College of Pharmacy, University of Florida, Gainesville, Florida, USA.

Clinical and Translational Science
|October 29, 2021
PubMed

Insights

The ADRB1 Arg389Arg genotype may predict risk for junctional ectopic tachycardia (JET) after pediatric heart surgery, particularly in patients not on beta-blockers. Further research is needed to confirm this association and the effect of beta-blocker treatment.

Area of Science:

  • Cardiovascular Genetics
  • Pediatric Cardiology
  • Pharmacogenomics

Background:

  • Junctional ectopic tachycardia (JET) is a serious postoperative complication in children with congenital heart defects.
  • Genetic factors, specifically beta-adrenergic receptor (ADRB) genotypes, are linked to arrhythmias in adults but not yet established in pediatric populations.
  • Understanding genetic predispositions can improve risk stratification for postoperative JET.

Purpose of the Study:

  • To investigate the association between ADRB1 and ADRB2 gene polymorphisms and the risk of developing postoperative JET in pediatric patients undergoing cardiac surgery.
  • To identify specific genotypes that may serve as predictors for JET in this vulnerable population.

Main Methods:

  • Genotyping of 45 children who developed JET and 298 controls for ADRB1 (p.Ser49Gly, p.Arg389Gly) and ADRB2 (p.Arg16Gly, p.Glu27Gln) polymorphisms.
  • Logistic regression analysis was used to assess genotype associations with JET, adjusting for clinical variables.
  • Subgroup analysis was performed on patients not receiving beta-blocker medication.

Main Results:

  • The ADRB1 Arg389Arg genotype showed a nominal association with increased JET risk in patients not on beta-blockers (OR=2.25, p=0.034).
  • No significant association was found for the Arg389Arg genotype in the overall population or for any other tested ADRB1/ADRB2 variants.
  • 13% of the 343 included children developed postoperative JET.

Conclusions:

  • The ADRB1 Arg389Arg genotype may be a potential predictor of JET risk in pediatric cardiac surgery patients, especially when not on beta-blocker therapy.
  • Further studies are warranted to validate this finding and explore the impact of beta-blocker treatment on this genetic association.

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