Concordance of Congenital Heart Defect in Monozygotic Twins in Brazil

ABSTRACT

Abstract Tetralogy of Fallot (TOF) consists of four cardiac changes interventricular communication, pulmonary stenosis, aortic dextroposition and right ventricular hypertrophy. The prevalence is 0.1 per 1,000 live births. A primiparous mother with gestational age of 38 weeks came to the emergency. At the time, it was verified in her twin pregnancy that one fetus had TOF, thus a pregnancy interruption was scheduled for the following day. In the neonatal physical examination of both, localized acrocyanosis, regular heart rhythm with the presence of a heart murmur, and good peripheral perfusion were found. The echocardiogram of twin 1 revealed patent foramen ovale; a wide perimembranous interventricular communication of misalignment, with the aorta riding the septum by 50%; hypertrophied and long infundibulum with pulmonary infundibulo-valvular stenosis, with a maximum systolic gradient of 66 mm Hg; both pulmonary arteries presented dimensions of 0.35 mm; pulmonary valve annulus 0.56 mm; and patent ductus arteriosus measuring 0.19 mm. The echocardiogram of twin 2 showed patent foramen ovale; a wide perimembranous interventricular communication of misalignment, with the aorta riding the septum by 50%; hypertrophied infundibulum with stenosis pulmonary infundibulo-valve, with a maximum systolic gradient of 33 mm Hg; reduced confluent pulmonary arteries; right pulmonary artery measuring 0.40 mm and left pulmonary artery measuring 0.55 mm; pulmonary valve annulus measuring 0.72 mm; a closed arterial canal, and mild aortic regurgitation. Tetralogy of Fallot is a multifaceted syndrome with a high prevalence in pediatrics. This case is the first case of congenital heart defect concordance for TOF in monozygotic twins in Brazil.