Role of fetal intertwin difference in middle cerebral artery peak systolic velocity in predicting neonatal twin anemia–polycythemia sequence

Abstract

Objectives To evaluate the relationship between the fetal intertwin difference in middle cerebral artery peak systolic velocity (MCA-PSV) and intertwin difference in hemoglobin (Hb) concentration at birth in monochorionic diamniotic (MCDA) twin pregnancies in order to assess its potential role in the prediction of twin anemia-polycythemia sequence (TAPS). MethodsThis was a retrospective cohort study of MCDA twin pregnancies delivered between January 2012 and January 2018. All pregnancies with measurements of MCA-PSV within 7 days prior to delivery and in which neonatal Hb concentration was available were included. The correlation between fetal intertwin difference in MCA-PSV, expressed in multiples of the median (MoM), and neonatal intertwin difference in Hb concentration was investigated. Receiver-operating characteristics (ROC) curve analysis was used to assess the performance of fetal intertwin difference in MCA-PSV for predicting intertwin difference in Hb > 90 th centile at birth.Results A total of 154 out of 256 MC twin pregnancies fulfilled the inclusion criteria. Fetal intertwin difference in MCA-PSV MoM correlated positively with neonatal intertwin difference in Hb concentration (r = 0.79; P < 0.001). The 90 th centile for intertwin difference in Hb was 7.25 g/dL. There were 15 (9.7%) cases with a Hb difference ≥ 7.25 g/dL at birth. ROC curve analysis showed a high accuracy of fetal intertwin MCA-PSV MoM difference for the prediction of neonatal intertwin Hb difference ≥ 7.25 g/dL at birth (area under the ROC curve, 0.976 (95% CI,; P = 0.012). The optimal cut-off for intertwin MCA-PSV MoM difference was 0.373, with a sensitivity of 93. 3% (95% CI, and a specificity of 95. 7% (95% CI,. The positive predictive value was 70% (95% CI, and the negative predictive value was 99.3% (95% CI, 95.9-100%).Conclusion Our findings show that fetal intertwin MCA-PSV MoM difference is a good predictor of neonatal intertwin Hb concentration difference > 90 th centile and potentially of TAPS.

Middle Cerebral Artery Doppler Velocimetry for the Diagnosis of Twin Anemia Polycythemia Sequence: A Systematic Review

“…The primary search of the Pubmed, Embase, and SCOPUS databases produced 432 publications. Based on abstract review, 54 of these publications were selected to be reviewed in their entirety [1,2,4,5,7,[9][10][11][12]16,19,. The secondary search of bibliographies produced three additional publications which were also reviewed in their entirety for a total 57 publications [6,66,67].…”

“…The publications are detailed in Table 1 and reasons for exclusion are summarized in Figure 1. Five of the 57 publications, all from the primary search, described a study of MCDA twins where serial ultrasounds with MCA-PSV values were collected to detect TAPS with direct comparison to Hb values [5,9,10,19,47]. After applying QUADAS II methodology to these five studies, four were determined highly likely to have bias in patient selection ( Figure 2) [5,9,10,47].…”

“…The answers to the QUADAS II signaling questions provide rationale for these assessments of bias and are detailed in Table 2. After applying QUADAS II methodology to these five studies, four were determined highly likely to have bias in patient selection ( Figure 2) [5,9,10,47]. Three were found highly likely to have bias in conduction or interpretation of the index test (i.e., MCA-PSV Doppler values) as well as conduction or interpretation of the standard reference (i.e., Hb levels) [5,10,47].…”

“…TAPS is caused by chronic blood transfusion through shared placental vessels leading to substantial morbidity as the twins become increasingly anemic and plethoric. While the disease may follow FLS (referred to here as "post-laser TAPS" (plTAPS)) in 3-10% of MCDA pregnancies, spontaneous TAPS (sTAPS), first described in 2007 by Lopriore et al, may develop 2-5% of the time [2][3][4][5][6][7][8]. Middle cerebral artery peak systolic velocity (MCA-PSV), as measured during Doppler velocimetry studies, is used to screen for TAPS.…”

Performance of Antenatal Diagnostic Criteria of Twin-Anemia-Polycythemia Sequence

“…Tollenaar et al found that an MCA PSV delta of >0.5 MoM had a higher sensitivity and negative predictive value in diagnosing TAPS antenatally than the traditional cut-off of >1.5 and <1.0 MoM [14]. Moreover, Tavares De Sousa et al reported that a delta of >0.373 MoM was in fact the most optimal predictor of twin Hb discordance of >90th centile at birth [15]. A recent consensus using the Delphi procedure has focused on alleviating heterogeneity and achieving a uniform diagnostic criteria for TAPS.…”