Influence of twin-twin transfusion syndrome on fetal cardiovascular structure and function: prospective case-control study of 136 monochorionic twin pregnancies

Abstract

Objective: To test the hypothesis that identical twins show no inter-twin differences in cardiovascular structure or physiology in fetal life unless there has been twin-twin transfusion syndrome. Design: Unselected prospective case-control observational study of fetoplacental haemodynamics including echocardiography at a median of 24 (16.7 to 32.3) weeks, with postnatal confirmation of congenital heart disease or normality. Setting: Fetal medicine unit. Patients: 136 women with monochorionic diamniotic twin pregnancies, of which 47 fetal twin pairs (35%) had twin-twin transfusion syndrome. Results: There were no haemodynamic differences between the bigger fetus (twin 1) and the smaller co-twin (twin 2) in uncomplicated monochorionic diamniotic pairs. In twin-twin transfusion syndrome, recipient fetuses had increased aortic and pulmonary velocities compared with their donor co-twins (mean (SD): 0.73 (0.23) m/s and 0.63 (0.14) m/s), respectively, v 0.53 (0.16) m/s and 0.48 (0.10) m/s in donor twins; p = 0.003 (aortic) and < 0.0001 (pulmonary)), and also in comparison with twin 1 and twin 2. The overall prevalence of congenital heart disease was increased above that in singletons (3.8% v 0.56%; 6.9% in twin-twin transfusion v 2.3% in uncomplicated monochorionic diamniotic twins), with inter-twin discordance for defects. The prevalence in recipient twins was 11.9% (p = 0.014 v uncomplicated control twins). Conclusions: Fetuses with an identical genome but no circulatory imbalance have similar cardiovascular physiology but discordant phenotypic expression of congenital heart disease. The high prevalence of congenital heart disease in monochorionic diamniotic twins merits detailed fetal echocardiography.

Non‐identical monozygotic twins, intermediate twin types, zygosity testing, and the non‐random nature of monozygotic twinning: A review

“…MC twin pairs may experience unequal blood flow through the developing cardiovascular system because of episodes of twin-to-twin transfusion (TTT) that may later manifest as the full TTT syndrome. In a series of 136 MC twin pairs, the prevalence of congenital heart malformation at birth was 3.8% versus 0.56% in singletons [Karatza et al, 2002]. The prevalence in TTT syndrome and in uncomplicated MC twins was 6.9% and 2.3% respectively.…”

Profiling fetal cardiac function in twin–twin transfusion syndrome

“…None of these cases had undergone any form of treatment before laser surgery. The median gestational at diagnosis was 20 (IQR, [18][19][20][21][22] weeks. Quintero Stages I and III cases were the most numerous in our study population, and there were very few Stage IV cases and no Stage V cases.…”

Drug Closure of a Patent Ductus Arteriosus in An Extremely Low Birth Weight Premature Newborn. A Case Report

“…Even though in dichorionic mono amniotic pregnancies there are no haemodynamic differences between the larger and the smaller fetus, in pregnancies where feto-fetal transfusion syndrome is present the receiver fetus has higher aortic and pulmonary velocities than the donor fetus. In addition the frequency of cardiac malformations is about 2.5 times higher in the case of twin pregnancies complicated with pathology [12][13][14]. Therefore followup of twin monochorionic pregnancies requires special care in assessing the cardiovascular system [15,16].…”