Umbilical Artery Doppler Patterns and Right Ventricular Outflow Abnormalities in Twin‐Twin Transfusion Syndrome

Abstract

Objectives-To evaluate the association of abnormal Doppler velocimetric patterns in the umbilical arteries (UAs) and right ventricular outflow tract abnormalities (RVOTAs) in twin-twin transfusion syndrome (TTTS) cases. Methods-This retrospective study involved women who had laser surgery for TTTS between January 2012 and May 2018 at a single institution. The prevalence of an RVOTA in either twin was compared among TTTS cases in which both twins had positive end-diastolic flow (EDF) in the UA and those in which either twin had intermittent or persistent absent/reversed UA EDF. Nonparametric tests were used for comparisons. Logistic regression was performed to identify variables associated with an RVOTA in either twin, adjusted for moderate or severe tricuspid regurgitation, right ventricular hypertrophy, right ventricular systolic or diastolic dysfunction, the Quintero stage, and other confounders. P < .05 was considered significant. Results-A total of 126 consecutive TTTS cases were included. Right ventricular outflow tract abnormalities were seen in 8.7% (11of 126) of cases, all in recipient twins. Significant differences in the rate of RVOTAs in the recipient twin were seen between TTTS cases with intermittent absent/reversed UA EDF and those with positive UA EDF (26.9% [7 of 26] versus 3.7% [3 of 82]; P = .002]. However, no significant differences were noted among the other study groups. Intermittent absent/reversed UA EDF was associated with a significantly increased risk for an RVOTA (adjusted odds ratio, 20.6 [95% confidence interval, 3.1-138]; P = .002) after adjusting for confounders. Conclusions-Intermittent changes in vascular impedance to UA flow may contribute to the pathogenesis of acquired right-sided cardiac lesions in the recipient twin affected with TTTS.

Comparison of renal artery Doppler parameters of monochorionic diamniotic twin pregnancies with and without twin-to-twin transfusion syndrome

“…[ 26 ] Development of the cardiac abnormality in RT can cause concentric hypertrophy, associated with impaired ventricular relaxation and shortened filling time. [ 27 ] These changes are reflected in the Doppler examination of fetal arteries, especially UA and MCA,[ 28 ] as confirmed by the results of the present study. As the fetal kidneys receive about 2%–3% of the total cardiac output, it was anticipated that the peripheral circulation (renal arteries) respond to the neurohormonal stimuli induced by hypoxia; however, the study rejected the association of RAD parameters with adverse neonatal outcomes suggests that it has yet to be elucidated how the fetal cardiovascular system adapts to chronic hypoxia.…”

Right ventricular outflow tract abnormalities in monochorionic twin pregnancies without twin‐to‐twin transfusion syndrome: Prenatal course and postnatal long‐term outcomes

“…Right ventricular outflow tract abnormalities (RVOTA), including pulmonary stenosis (PS), pulmonary atresia (PA), steno‐insufficiency (PSI) and insufficiency (PI) are heart defects mainly reported in the recipient twin (RT) of monochorionic/diamniotic (MC/DA) twin pregnancies with twin‐to‐twin transfusion syndrome (TTTS) both in its natural history 1‐4 and in cases treated by fetoscopic laser surgery (FLS) 5,6 …”

“…Right ventricular outflow tract abnormalities (RVOTA), including pulmonary stenosis (PS), pulmonary atresia (PA), steno-insufficiency (PSI) and insufficiency (PI) are heart defects mainly reported in the recipient twin (RT) of monochorionic/diamniotic (MC/DA) twin pregnancies with twin-to-twin transfusion syndrome (TTTS) both in its natural history [1][2][3][4] and in cases treated by fetoscopic laser surgery (FLS). 5,6 RVOTA have also been sporadically reported in MC, not complicated by TTTS, along with other complications of MC twins, such as selective fetal growth restriction (sFGR), 7 twin anemiapolycythemia sequence (TAPS) 8 and amniotic fluid discordance (AFD).…”

Incidence, prognosis, and perinatal outcomes of and risk factors for severe twin–twin transfusion syndrome with right ventricular outflow tract obstruction in the recipient twin after fetoscopic laser photocoagulation

“…The recipient twin may have higher renin–angiotensin activity than the donor twin, leading higher incidence of RVOTO in recipient twins [ 15 ]. Differences in volume overload, with volume overload occurring more frequently in recipient than in donor twins due to intermittent absent or reversed umbilical artery end-diastolic flow, have also been reported to increase the incidence of recipient-twin RVOTO [ 16 ]. However, the true etiology of RVOTO in recipient twins remains unclear [ 17 ].…”