Cumulative patient effective dose and acute radiation-induced chromosomal DNA damage in children with congenital heart disease

TLDR

Infants undergoing cardiac catheterisation are exposed to diagnostic radiation, and the BEIR VII report highlights the need for studies on this vulnerable population. This study aimed to estimate the lifetime attributable risk of cancer from cumulative radiological dose in 59 children with complex congenital heart disease and to evaluate chromosomal DNA damage after catheterisation. Cumulative exposure was quantified as effective dose in mSv and LAR derived from BEIR VII, while a subset of 18 patients had micronucleus assays before and 2 h after procedures, and dose‑area product was recorded, yielding a median lifetime effective dose of 7.7 mSv. Cardiac catheterisation and CT accounted for 95 % of the total effective dose, with median LAR cancer of 1 in 382 for a 1‑year‑old and a significant rise in micronucleus frequency post‑procedure, underscoring the need for strict radiation dose optimisation in children.

Abstract

The seventh Committee on "Biological Effects of Ionizing Radiation" (BEIR VII, 2006) underlines "the need of studies of infants who are exposed to diagnostic radiation because catheters have been placed in their hearts".To determine the lifetime attributable risk (LAR) of cancer associated with the estimated cumulative radiological dose in 59 children (42 male, age 2.8+/-3.2 years) with complex congenital heart disease, and to assess chromosomal DNA damage after cardiac catheterisation procedures. Methods In all patients, the cumulative exposure was estimated as effective dose in milliSievert (mSv), and LAR cancer was determined from the BEIR VII report. In a subset of 18 patients (13 male, age 5.2+/-5.7 years) micronucleus as a biomarker of DNA damage and long-term risk predictor of cancer was assayed before and 2 h after catheterisation procedures. Dose-area product (Gy cm(2)) was assessed as a measure of patient dose.The median life time cumulative effective dose was 7.7 mSv per patient (range 4.6-41.2). Cardiac catheterisation procedures and CT were responsible for 95% of the total effective dose. For a 1-year-old child, the LAR cancer was 1 in 382 (25th to 75th centiles: 1 in 531 to 1 in 187) and 1 in 156 (25th to 75th centiles: 1 in 239 to 1 in 83) for male and female patients, respectively. Median micronucleus values increased significantly after the procedure in comparison with baseline (before 6 per thousand vs after 9 per thousand, p=0.02). The median dose-area product value was 20 Gy cm(2) (range 1-277).Children with congenital heart disease are exposed to a significant cumulative dose. Indirect cancer risk estimations and direct DNA data both emphasise the need for strict radiation dose optimisation in children.