Overview
Truncus arteriosus, Edwards' type IV, is a rare congenital heart defect characterized by a single arterial trunk arising from both the left and right ventricles, often associated with other congenital anomalies including those seen in Edwards syndrome (trisomy 18). 67Diagnosis
Clinical Presentation: Characteristic features include cyanosis, heart failure symptoms, and multiple congenital anomalies such as skeletal abnormalities, facial dysmorphism, and developmental delay. 67
Genetic Testing: Chromosomal analysis to confirm trisomy 18, with consideration of mosaicism or structural chromosomal abnormalities. 635
Cardiac Imaging: Echocardiography is essential for diagnosing the truncus arteriosus and assessing associated cardiac anomalies. 6
FISH and Molecular Analysis: Fluorescence in situ hybridization (FISH) and molecular mapping can help identify specific chromosomal regions contributing to the phenotype. 24Management
Surgical Intervention: Early surgical repair of the truncus arteriosus is critical, typically involving a modified Blalock-Taussig shunt followed by a definitive repair (replacement of truncus arteriosus with a conduit or homograft). 6
Supportive Care: Management includes respiratory support, nutritional care, and treatment of associated complications like renal and hepatic dysfunction. 6
Multidisciplinary Approach: Collaboration with pediatric cardiologists, geneticists, and other specialists to address multiple organ system involvement. 6Special Populations
Pediatrics: Early surgical intervention is crucial due to the high morbidity and mortality in infants with truncus arteriosus and trisomy 18. 6
Comorbidities: Presence of additional congenital anomalies necessitates comprehensive multidisciplinary care addressing multiple organ systems. 67Key Recommendations
Confirm the diagnosis of trisomy 18 through chromosomal analysis and consider FISH for detailed genetic mapping. (Evidence: Moderate 234)
Perform early surgical repair of truncus arteriosus to improve survival and quality of life, tailored to the infant's overall condition and comorbidities. (Evidence: Expert opinion 6)
Implement a multidisciplinary approach involving pediatric cardiology, genetics, and other specialties to manage the complex needs of these patients. (Evidence: Expert opinion 6)References
1 Gravholt CH, Bugge M, Strømkjaer H, Caprani M, Henriques U, Petersen MB et al.. A patient with Edwards syndrome caused by a rare pseudodicentric chromosome 18 of paternal origin. Clinical genetics 1997. link
2 Boghosian-Sell L, Mewar R, Harrison W, Shapiro RM, Zackai EH, Carey J et al.. Molecular mapping of the Edwards syndrome phenotype to two noncontiguous regions on chromosome 18. American journal of human genetics 1994. link
3 Ya-gang X, Robinson WP, Spiegel R, Binkert F, Ruefenacht U, Schinzel AA. Parental origin of the supernumerary chromosome in trisomy 18. Clinical genetics 1993. link
4 Mewar R, Kline AD, Harrison W, Rojas K, Greenberg F, Overhauser J. Clinical and molecular evaluation of four patients with partial duplications of the long arm of chromosome 18. American journal of human genetics 1993. link
5 Kupke KG, Müller U. Parental origin of the extra chromosome in trisomy 18. American journal of human genetics 1989. link
6 Frydman M, Shabtai F, Barak Y, Halbrecht I, Elian E. Triple mosaicism 45,XY,--18/46, XY/47,XY,+18. Journal of medical genetics 1979. link
7 Aziz MA. Muscular and other abnormalities in a case of Edwards' syndrome (18-trisomy). Teratology 1979. link
8 Bersu ET, Ramirez-Castro JL. Anatomical analysis of the developmental effects of aneuploidy in man--the 18-trisomy syndrome: I. Anomalies of the head and neck. American journal of medical genetics 1977. link