Researchers explored clinical and genetic factors associated with atrial tachycardia (AT) after CHD surgery in infants younger than 1-year-old. They examined variants in the genes PITX2 and IL6, which are associated with postoperative atrial fibrillation in adults after cardiac surgery.

Heartbeat Rhythm

Arrhythmias disruptions in the rhythm of the heartbeat after congenital heart disease (CHD) surgery in children are common and contribute to increased morbidity and mortality. The investigators reported in the August issue of American Heart Journal that 15% of infants enrolled in the study experienced AT after CHD surgery.

AT was associated with the need for extracorporeal membrane oxygenation (ECMO) support and longer duration of ventilation, intensive care unit stays, and hospital stays. Variations in PITX2 and IL6 were not associated with postoperative AT.

Risk factors for AT included the use of two or more inotropes (drugs that increase the force of the heart's contraction), neonatal age less than 28 days at surgery, and higher surgical complexity scores.

Postoperative Atrial Fibrillation

Atrial tachycardia (AT) after infant congenital heart disease (CHD) surgery is associated with increased mortality. Polymorphisms in PITX2 (rs2200733) and IL6 (rs1800795) are associated with postoperative atrial fibrillation in adults but have not been studied in CHD.

The objective was to test the hypothesis that clinical factors and variants in PITX2 and IL6are associated with postoperative AT in infants with CHD. Infants (<1 year of age) undergoing CHD surgery between September 2007 and May 2016 were included. Subjects had a daily assessment of telemetry and were genotyped for the 2 variants.

Mortality And Morbidity

Univariate and multivariate analyses were performed to test for factors independently associated with AT. AT occurs in 15% of infants after CHD surgery and is associated with increased morbidity and mortality.

Genetic Variants

Risk factors include the use of 2 or more inotropes, neonatal age, and higher surgical complexity score. They observed no association between common genetic variants in PITX2 and IL6 and AT in infants after CHD surgery.