Year: 2019
Type: erratum
Abstract: Correction of d-Transposition of the Great Arteries Sooner Rather Than LaterArticle, see p 2728 W ith survival into adulthood now expected for patients with even the most complex forms of congenital heart disease (CHD), improvements in the neurological and developmental outcomes of CHD survivors are an increasingly urgent priority.Yet identification of modifiable risk factors for adverse neurodevelopmental outcome remains a challenge.Complex CHD is comprised of rare, heterogeneous lesions and diverging management strategies, as well as multiple additive, colinear, and interacting risk factors.These include genetic variants, parental education, fetal circulatory disturbances, intraoperative factors, and postoperative complications.Neurodevelopmental risk can further accrue from morbidities and procedures occurring after discharge (eg, arrhythmia, malnutrition, or stroke).Although bypass variables are among the most easily modified risk factors and, hence, the most amenable to randomized trials, the largest percent variance in neurodevelopmental outcomes is likely contributed by preoperative and innate patient factors. 1 To sort out their contribution to neurological outcome, it is helpful to study a homogeneous patient population with few potential confounders.Patients with dextro-transposition of the great arteries (d-TGA) with intact ventricular septum or ventricular septal defect (VSD), repaired with the arterial switch operation (ASO), constitute an ideal group in which to assess the relative contributions of preoperative risk factors to neurological outcomes.They rarely have coexisting extracardiac anomalies or genetic syndromes.Moreover, residual significant hemodynamic problems following the ASO are uncommon, with infrequent need for reoperation.2 Yet, adolescents with d-TGA show abnormalities in neurodevelopment and brain structure.They have impaired performance in tasks of memory, visual-spatial skills, attention, executive functioning, and social cognition relative to the general population.3,4 Brain MRIs in adolescents with d-TGA show abnormalities in white matter microstructure and cortical thickness.5,6 In some cases, brain network abnormalities correlate with cognitive disabilities.7,8 Because the d-TGA population is so healthy after recovery from the ASO, their abnormalities of brain structure and function likely arise from a combination of innate, fetal/perinatal, and perioperative risk factors.To understand the origins of neurodevelopmental disabilities in d-TGA, it is helpful to review its unique physiology.The pulmonary artery and aorta are transposed in d-TGA, meaning that in utero oxygen and nutrient-rich blood from the placenta is preferentially directed to the lungs, whereas deoxygenated, nutrient-deficient blood is recirculated to the brain.Increased cerebral blood flow may partially compensate, but fetal cerebral oxygen and nutrient delivery is lower than normal.After birth, especially among those with intact ventricular septum or small VSD, patients with d-TGA are often profoundly cyanotic, with reduced cerebral oxygen delivery.9
Source: Circulation
Authors: Caitlin K. Rollins, Jane W. Newburger
Institutions: Boston Children's Hospital, Harvard University
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2949257574