CLINICAL AND ECHOGRAPHIC FEATURES OF IN-UTERO CARDIAC DYSFUNCTION IN THE RECIPIENT TWIN IN TWIN-TWIN TRANSFUSION SYNDROME

Objective-Fetal twin-twin transfusion syndrome (TTTS) presenting in th e second trimester has been associated with almost no perinatal surviv al until recently, when serial drainage of amniotic fluid has improved the prognosis to 70%-80%. Most recipient twins now survive but develo p cardiac dysfunction. The study was undertaken to evaluate the abnorm al echocardiographic features and clinical complications of cardiac di sease in the recipient twin of TTTS. Design-Antenatal and postnatal ec hocardiographic and clinical observational study. Setting-Antenatal st udies in a tertiary referral centre. Postnatal management and follow u p were performed by the same paediatric cardiologist, either at the ob stetric hospital or at the regional referral centre. Patients-Twin pre gnancies complicated by TTTS with severe polyhydramnios diagnosed earl ier than 25 weeks that proceeded until viability (n = 5). Intervention -Serial fetal echocardiography with colour Doppler. Postnatal echocard iography in the first week and between two and seven months. Serial am nioreduction was performed in all pregnancies. Digoxin treatment, peri cardiocentesis, paracentesis, or laser ablation of placental anastomos es was undertaken when there was hydrops. Results-Increased cardiothor acic ratio and tricuspid regurgitation were seen in all recipient twin s. High pulmonary artery velocities developed in three. One recipient twin died a week after delivery of endocardial fibroelastosis infundib ular pulmonary stenosis. others had balloon dilatation for pulmonary s tenosis, one shortly after birth and one at four months. A further twi n has apical thickening of the right ventricle at six months. The rema ining recipient twin had normal echocardiographic findings at follow u p. Conclusion-This report characterises for the first time a cardiac d isease acquired in utero in the recipient twin in pregnancies complica ted by TTTS. Clinical manifestations in utero range from mild to criti cal pulmonary stenosis or lethal cardiomyopathy. Although perinatal pr ognosis seems to be related to the severity of dysfunction when first diagnosed in utero, follow up in infancy is recommended in view of the possibility of progressive pulmonary stenosis.