Neonatal Surgeries for Complex Congenital Heart Disease Rise, Remain High After Fukushima

By Marilynn Larkin

March 23, 2019

NEW YORK (Reuters Health) - Following the 2011 Fukushima nuclear accident in Japan, complex congenital heart disease (CHD) operations increased in neonates, and the number of operations remain high despite declining air levels of radiation, researchers say.

Dr. Kaori Murase of Nagoya City University Graduate School of Natural Sciences in Japan and colleagues studied data from 2007 to 2014 on CHD operations performed on children in Japan from birth to age 17. They separated CHDs into groups based on complexity, the time of occurrence during heart development, and age at operation.

As reported online March 13 in the Journal of the American Heart Association, they found a significant 14.2% increase in the number of complex CHD operations in neonates and infants per 100,000 live births; however, no significant increase was seen in operations performed for patients ages one to 17.

The number of CHD operations for neonates and infants has remained high, Dr. Murase told Reuters Health, "in spite of the declining air dose." Therefore, it is possible that "internal exposure" and "low-dose exposure" may be having an impact by affecting the food supply and specific neighborhoods - issues that may be subjects of further study.

"We also analyzed which types of CHDs were negatively influenced, so we believe this study can contribute to molecular biological research and acceleration of gene therapy and other (treatments)," he said by email.

Specifically, the complex CHDs that showed significant increases were those known to occur early on, during various developmental stages of the heart, e.g., single ventricle or hypoplastic left heart syndrome and very early and relatively early tetralogy of Fallot.

"A nuclear accident is a problem that directly affects the lives of each of us," Dr. Murase said. "We should continue to pay attention to it and not underestimate its effects."

"In recent years, the number of cardiac operations has increased remarkably even in adults in Japan," he noted. The team did not analyze this trend in the current study because they would have had to consider potential confounders, such as aging. "However, we think that adults as well as neonates and infants should be monitored to enable early detection," Dr. Murase said.

American Heart Association expert Dr. Hugh Allen of Baylor College of Medicine, Texas Children's Hospital in Houston, told Reuters Health the study was "carefully done and well written."

"The authors found an increase in the incidence of complex heart surgeries on infants born after the Fukushima nuclear accident but not in older patients," he noted. "Although it is tempting to connect the dots from the accident to the increased operative volume, cause and effect cannot be determined without knowing specific patient's radiation dosages."

"Nonetheless," he told Reuters Health by email, "it is interesting to speculate a probable situation that is more than coincidence."

"Regarding implications for clinicians in the U.S., it would be interesting - if all data could be captured - to see if the incidence of CHD in infants is increased near nuclear test sites, nuclear accident sites, and storage sites," he said. "From this study, my guess is that it is."


J Am Heart Assoc 2019.