Transposition of the great arteries

Abstract

Transposition of the great arteries (TGA), also referred to as complete transposition, is a congenital cardiac malformation characterised by atrioventricular concordance and ventriculoarterial (VA) discordance. The incidence is estimated at 1 in 3,500-5,000 live births, with a male-to-female ratio 1.5 to 3.2:1. In 50% of cases, the VA discordance is an isolated finding. In 10% of cases, TGA is associated with noncardiac malformations. The association with other cardiac malformations such as ventricular septal defect (VSD) and left ventricular outflow tract obstruction is frequent and dictates timing and clinical presentation, which consists of cyanosis with or without congestive heart failure. The onset and severity depend on anatomical and functional variants that influence the degree of mixing between the two circulations. If no obstructive lesions are present and there is a large VSD, cyanosis may go undetected and only be perceived during episodes of crying or agitation. In these cases, signs of congestive heart failure prevail. The exact aetiology remains unknown. Some associated risk factors (gestational diabetes mellitus, maternal exposure to rodenticides and herbicides, maternal use of antiepileptic drugs) have been postulated. Mutations in growth differentiation factor-1 gene, the thyroid hormone receptor-associated protein-2 gene and the gene encoding the cryptic protein have been shown implicated in discordant VA connections, but they explain only a small minority of TGA cases.The diagnosis is confirmed by echocardiography, which also provides the morphological details required for future surgical management. Prenatal diagnosis by foetal echocardiography is possible and desirable, as it may improve the early neonatal management and reduce morbidity and mortality. Differential diagnosis includes other causes of central neonatal cyanosis. Palliative treatment with prostaglandin E1 and balloon atrial septostomy are usually required soon after birth. Surgical correction is performed at a later stage. Usually, the Jatene arterial switch operation is the procedure of choice. Whenever this operation is not feasible, adequate alternative surgical approach should be implemented. With the advent of newer and improved surgical techniques and post operative intensive care, the long-term survival is approximately 90% at 15 years of age. However, the exercise performance, cognitive function and quality of life may be impaired.

A Strategy for Comparing the Contributions of Environmental Chemicals and Other Risk Factors to Neurodevelopment of Children

“…The incidence of TOF is 4 in 10,000 (Child 2004), or 10,200 cases in children 0-5 years of age in the United States. The incidence of d-TGA is 3 in 10,000 (Martins and Castela 2008), or 7,650 cases, and the incidence of HLHS is 2 in 10,000 (Barron et al 2009 (Hamilton et al 2010). In a metaanalysis of 15 studies (1,556 cases; 1,720 controls), Bhutta et al (2002) calculated a mean FSIQ deficit among cases of 10.85 points, producing a total loss of 34,031,025 FSIQ points.…”

Angeborene Herzfehlbildungen von Septen, Endokardkissen und Konotrunkus

“…Das Geschlechterverhältnis (m:w) liegt bei 1,5-3,2:1. Die genaue Ätiologie der TGA ist bisher nicht bekannt [13]. Theorien und Embryogenese lassen eine anomale Infundibulumrotation bzw.…”

Simplifying ultrasound assessment of the fetal heart: Incorporating the complete Three Vessel View into routine screening

“…This occurs in 1/3500–5000 live births and accounts for 4–7% of all congenital heart diseases 49 . Simple transposition can be successfully treated by arterial switch operation in the first week of life, with good surgical results and low mortality.…”