Fetal middle cerebral artery Doppler fluctuations after laser surgery for twin-twin transfusion syndrome

Alterations in Fetal Doppler Parameters Before and Twenty-Four Hours After Radiofrequency Ablation for Twin Reversed Arterial Perfusion Sequence

Objective

To evaluate alterations in the fetal Doppler parameters of pump fetuses before and 24 h after radiofrequency ablation surgery for twin reversed arterial perfusion sequence (TRAPs).

Methods

This is a retrospective study of 28 pump fetuses in TRAPs and 28 normal control twins between 2016 and 2021. The fetal Doppler parameters, including the umbilical artery pulsatility index (UA-PI), middle cerebral artery peak systolic velocity (MCA-PSV), middle cerebral artery pulsatility index (MCA-PI), and cerebroplacental ratio (CPR), of the controls, and pump fetuses before and 24 h after surgery were compared.

Results

An increasing trend and a further increase in the MCA-PSV, MCA-PI, MCA-PSV Z score, and MCA-PI Z score after surgery were observed in pump fetuses with gestational age (GA) ≥20 weeks; however, such changes were not observed in those with a GA of <20 weeks. The UA-PI and CPR before and after surgery were not different between control and pump fetuses, whether the GA was ≥20 or <20 weeks.

Conclusion

In the middle second trimester, the pump fetus might suffer from high cardiac output rather than hypoxemia before surgery and congestive heart failure, or hemodilutional anemia after surgery. This may provide some theoretical evidence in favor of early intervention, rather than waiting for a more advanced GA, to avoid unnecessary hemodynamic alterations.

Perioperative fetal hemodynamic changes in twin-twin transfusion syndrome and neurodevelopmental outcome at two years of age

Objective

To investigate whether perioperative fetal hemodynamic changes in twin‐to‐twin transfusion syndrome (TTTS) are associated with neurodevelopmental impairment (NDI) at two years.

Methods

Doppler parameters of three sonograms (day before, first day after and 1 week after laser surgery for TTTS) were assessed for correlation with neurodevelopmental outcome at two years (2008‐2016). NDI was defined as: cerebral palsy, deafness, blindness, and/or a Bayley‐III cognitive/motor developmental test‐score > 2SD below the mean.

Results

Long‐term outcome was assessed in 492 TTTS survivors. NDI was present in 5% (24/492). After adjustment for severe cerebral injury (present in 4%), associated with NDI were: middle cerebral artery peak systolic velocity (MCA‐PSV) >1.5 multiples of the median (MoM) 1 day after surgery (odds ratio [OR] 4.96; 95% confidence interval [CI]: 1.17‐21.05, P = .03), a change from normal umbilical artery pulsatility index (UA‐PI) presurgery to UA‐PI >p95 postsurgery (OR 4.19; 95% CI: 1.04‐16.87, P = .04), a change from normal to MCA‐PSV >1.5MoM (OR 4.75; 95% CI: 1.43‐15.77, P = .01).

Conclusion

Perioperative fetal hemodynamic changes in TTTS pregnancies treated with laser are associated with poor neurodevelopmental outcome. Prospective research on the cerebrovascular response to altered hemodynamic conditions is necessary to further understand the cerebral autoregulatory capacity of the fetus in relation to neurodevelopmental outcome.

Outcomes following selective fetoscopic laser ablation for twin-to-twin transfusion syndrome: a single-centre experience

INTRODUCTION

Fetoscopic laser photocoagulation (FLP), a treatment option for twin-to-twin transfusion syndrome (TTTS) in monochorionic twin pregnancies, is currently the treatment of choice at our centre. We previously reported on our experience of FLP from June 2011 to March 2014. This paper audits our fetal surgery performance since then.

METHODS

15 consecutive patients who underwent FLP for Stage II-III TTTS before 26 weeks of gestation from June 2011 to January 2017 were retrospectively reviewed, consisting of five cases from our initial experience and ten subsequent cases. Perioperative, perinatal and neonatal outcomes were analysed.

RESULTS

Of 15 pregnancies, 10 (66.7%) and 5 (33.3%) were for Stage II and III TTTS respectively, with FLP performed at an earlier Quintero stage in the later cohort. Overall mean gestational ages at presentation, laser and delivery were comparable between the cohorts at 19.7 (15.4-24.3) weeks, 20.3 (16.3-25.0) weeks and 31.2 (27.6-37.0) weeks, respectively. 2 (13.3%) cases had intra-amniotic bleeding and 1 (6.7%) had iatrogenic septostomy. 1 (6.7%) case had persistent TTTS requiring repeat FLP, and another (6.7%) had preterm premature rupture of membranes at seven weeks post procedure. The overall perinatal survival rate was 21 (75.0%) out of 28 infants. One mother underwent termination of pregnancy for social reasons at 1.4 weeks post procedure. Double survival occurred in 8 (57.1%) out of 14 pregnancies, while 13 (92.9%) had at least one survivor.

CONCLUSION

FLP requires a highly specialised team and tertiary neonatal facility. Continual training improves maternal and perinatal outcomes, ensuring comparable standards with international centres.

Diastolic dysfunction and cerebrovascular redistribution precede overt recipient twin cardiomyopathy in early-stage twin-twin transfusion syndrome

BACKGROUND

Indications for intervention in early-stage (Quintero I and II) twin-twin transfusion syndrome (TTTS) are not standardized. Fetal echocardiography can be used to guide the management of early-stage patients. The aim of this study was to identify early cardiovascular findings that may precede progression to overt recipient twin (RT) cardiomyopathy in early-stage TTTS.

METHODS

This was a retrospective review of pregnancies evaluated from 2004 to 2010. Subjects were included when initial evaluation identified Quintero I or II TTTS without evidence of "overt" RT cardiomyopathy, defined on the basis of atrioventricular valve regurgitation, ventricular hypertrophy, and abnormal Doppler myocardial performance indices. Patients elected management with observation or amnioreduction. Pregnancies were grouped by whether the RT developed overt cardiomyopathy. Initial values, including myocardial performance index, diastolic filling time corrected for heart rate (Doppler inflow duration/cardiac cycle length), pulsatility indices of the ductus venosus, umbilical artery, and middle cerebral artery, and cerebroplacental ratio (middle cerebral artery PI/umbilical artery PI), were compared.

RESULTS

Of 174 pregnancies evaluated with early-stage TTTS, 45 (26%) did not show evidence of RT cardiomyopathy. Follow-up echocardiography identified cardiomyopathy in 20 of 45 RTs (44%). Those RTs with subsequent cardiomyopathy had shorter diastolic filling times corrected for heart rate, higher ductus venosus PIs, lower middle cerebral artery PIs, and lower cerebroplacental ratios on initial echocardiography.

CONCLUSION

Diastolic dysfunction and cerebroplacental redistribution precede findings of overt cardiomyopathy in RTs with early-stage TTTS. Assessment of these parameters may allow earlier identification of RTs with cardiac disease and help guide management. Prospective studies are needed to assess the role of echocardiography in patient selection for the treatment of early-stage TTTS.