Twin reversed arterial perfusion (TRAP) sequence

doi:10.1017/CBO9780511997778.022

Chapter 12.1 - Twin reversed arterial perfusion (TRAP) sequence

Pathophysiology

from Section 2 - Fetal disease

Published online by Cambridge University Press: 05 February 2013

Martin A. Weber and

Edited by

Anthony Johnson and

Mark D. Kilby: Affiliation:
Department of Fetal Medicine, University of Birmingham
Anthony Johnson: Affiliation:
Baylor College of Medicine, Texas
Dick Oepkes: Affiliation:
Department of Obstetrics, Leiden University Medical Center

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Summary

Introduction

Twin reversed arterial perfusion (TRAP) sequence, acardiac anomaly, and chorioangiopagus parasiticus are synonymous terms referring to a rare complication of monochorionic multiple pregnancy characterized by a lack of a well-formed cardiac structure in one fetus (the acardiac twin, which also has numerous associated developmental abnormalities) which is abnormally perfused by a structurally normal co-twin (the “pump” twin) via a large superficial artery-to-artery placental anastomosis. TRAP sequence is therefore unique to monochorionic twins, since the presence of a placental anastomosis is required, and is a consequence of an underlying abnormality of the twinning process and therefore not encountered in singleton pregnancies. TRAP sequence affects around 1 in 35000–40000 pregnancies, representing around 1% of monochorionic twins [1], although higher incidences have been recorded in some series [2]. The pathophysiological basis and pathology of the condition will be discussed below. In this section, prenatal diagnosis and treatment will only be briefly discussed in relation to our understanding of the pathophysiology of the condition; detailed discussion of treatment options is presented in the subsequent section.

Historical perspective

The condition has various names and the term “acardiac monster” was first described in the sixteenth century. It was associated with twin gestation in the early eighteenth century [3]. Having initially been thought to represent a consequence of maternal exposure to environmental events, such as the guillotine, it was demonstrated in the early 1800s that the underlying abnormality was related to vascular abnormalities, and in particular to a primary abnormality or failure of cardiac development in the affected fetus. In 1850 Meckel suggested that the pathogenetic mechanism may be reversed perfusion due to large vascular anastomoses [3]. It is now well documented that many cases are not truly acardiac, and prenatal ultrasound data (see later section) have also demonstrated in some cases the presence of apparently normal cardiac function in early pregnancy with subsequent development of typical TRAP features.

Keywords

twin reversed arterial perfusion sequence placental vascular channels pregnancy prenatal diagnosis monochorionic twin pregnancy fetal growth acardiac fetus

Type: Chapter
Information: Fetal Therapy
Scientific Basis and Critical Appraisal of Clinical Benefits
, pp. 187 - 192

DOI: https://doi.org/10.1017/CBO9780511997778.022 [Opens in a new window]

Publisher: Cambridge University Press

Print publication year: 2012

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References

Weber, MA, Sebire, NJ. Genetics and developmental pathology of twinning. Semin Fetal Neonatal Med 2010;15:313–18.Google Scholar

Chanoufi, MB, Ben Temime, R, Masmoudi, A, et al. Clinical and anatomic features of acardiac twins. Med Princ Pract 2004;13:375–9.Google Scholar

Obladen, M. From monster to twin reversed arterial perfusion: a history of acardiac twins. J Perinat Med 2010;38:247–53.Google Scholar

Dahiya, P, Agarwal, U, Sangwan, K, Sen, J. Antenatal diagnosis of twin-reversed arterial perfusion sequence (acardiac amorphous) in a triplet pregnancy: case report. Arch Gynecol Obstet 2004;269:147–8.Google Scholar

Weisz, B, Peltz, R, Chayen, B, et al. Tailored management of twin reversed arterial perfusion (TRAP) sequence. Ultrasound Obstet Gynecol 2004;23:451–5.Google Scholar

Sogaard, K, Skibsted, L, Brocks, V. Acardiac twins: pathophysiology, diagnosis, outcome and treatment. Fetal Diagn Ther 1999;14:53–59.Google Scholar

Sato, T, Kaneko, K, Konuma, S, Sato, I, Tamada, T. Acardiac anomalies: review of 88 cases in Japan. Asia Oceania J Obstet Gynaecol 1984;10:45–52.Google Scholar

Severn, CB, Holyoke, EA. Human acardiac anomalies. Am J Obstet Gynecol 1973;116:358–65.Google Scholar

Baldwin, VJ. Anomalies of monozygotic duplication. In: Pathology of Multiple Pregnancy. New York, Springer-Verlag. 1994; 277–349.

Shih, JC, Shyu, MK, Hunag, SF, et al. Doppler waveform analysis of the intertwin blood flow in acardiac pregnancy: implications for pathogenesis. Ultrasound Obstet Gynecol 1999;14:375–9.Google Scholar

Moore, TR, Gale, S, Benirschke, K. Perinatal outcome of forty nine pregnancies complicated by acardiac twinning. Am J Obstet Gynecol 1990;163:907–12.Google Scholar

Healey, MG. Acardia: predictive risk factors for the co-twin’s survival. Teratology 1994;50:205–13.Google Scholar

Buntinx, IM, Bourgeois, N, Buytaert, PM, Dumon, JE. Acardiac amorphous twin with prune belly sequence in the co-twin. Am J Med Genet 1991;39:453–7.Google Scholar

Genest, DR, Lage, JM. Absence of normal-appearing proximal tubules in the fetal and neonatal kidney: prevalence and significance. Hum Pathol 1991;22:147–53.Google Scholar

Habbal, OA, Kenue, RK, Venugopalan, P. Acardia syndrome coexisting with gastroschisis in the co-twin. Clin Dysmorphol 2005;14:45–7.Google Scholar

Popek, EJ, Strain, JD, Neumann, A, Wilson, H. In utero development of pulmonary artery calcification in monochorionic twins: a report of three cases and discussion of the possible etiology. Pediatr Pathol 1993;13:597–611.Google Scholar

Kosno-Kruszewska, E, Deregowski, K, Schmidt-Sidor, B, et al. Neuropathological and anatomopathological analyses of acardiac and “normal” siblings in an acardiac-twin pregnancy. Folia Neuropathol 2003;41:103–9.Google Scholar

Benirschke, K, Kaufmann, P. Pathology of the Human Placenta. 2nd edn. New York, Springer. 1995; 702–10.

French, CA, Bieber, FR, Bing, DH, Genest, DR. Twins, placentas, and genetics: acardiac twinning in a dichorionic, diamniotic, monozygotic twin gestation. Hum Pathol 1998;29:1028–31.Google Scholar

Masuzaki, H, Miura, K, Yoshimura, S, Yoshiura, K, Ishimaru, T. A monozygotic twin pregnancy discordant for acardia and X-inactivation pattern. Eur J Obstet Gynecol Reprod Biol 2004;117:102–4.Google Scholar

Steffensen, TS, Gilbert-Barness, E, Spellacy, W, Quintero, RA. Placental pathology in Trap sequence: clinical and pathogenetic implications. Fetal Pediatr Pathol 2008; 27:13–29.Google Scholar

Chen, CP, Shih, SL, Liu, FF, et al. Skeletal deformities of acardius anceps: the gross and imaging features. Pediatr Radiol 1997;27:221–5.Google Scholar

Chi, JG. Acardiac twins – an analysis of 10 cases. J Korean Med Sci 1989;4:203–16.Google Scholar

Gimenez-Scherer, JA, Davies, BR. Malformations in acardiac twins are consistent with reversed blood flow: liver as a clue to their pathogenesis. Pediatr Dev Pathol 2003;6:520–30.Google Scholar

Park, HW, Kapur, RP, Shepard, TH. Reversed circulation in acardiac fetuses is associated with anatomic inversions in the aortic wall. Teratology 1994;49:267–72.Google Scholar

Laure-Kamionowska, M, Maslinska, D, Deregowski, K, Piekarski, P, Raczkowska, B. Effects of ischaemia and hypoxia on the development of the nervous system in acardiac foetus. Folia Neuropathol 2004;42:227–33.Google Scholar

Morizane, M, Ohara, N, Mori, T, Murao, S. Neuropathological features of the brain in acardius acormus. J Perinat Med 2002;30:269–72.Google Scholar

Sergi, C, Schmitt, HP. Central nervous system in twin reversed arterial perfusion sequence with special reference to examination of the brain in acardius anceps. Teratology 2000;61:284–90.Google Scholar

Petersen, BL, Broholm, H, Skibsted, L, Graem, N. Acardiac twin with preserved brain. Fetal Diagn Ther 2001;16:231–3.Google Scholar

Wong, AE, Sepulveda, W. Acardiac anomaly: current issues in prenatal assessment and treatment. Prenat Diagn 2005;25:796–806.Google Scholar

Moore, CA, Buehler, BA, McManus, BM, et al. Acephalus- acardia in twins with aneuploidy. Am J Med Genet Suppl 1987;3:139–43.Google Scholar

Blaicher, W, Repa, C, Schaller, A. Acardiac twin pregnancy: associated with trisomy 2: case report. Hum Reprod 2000;15:474–5.Google Scholar

Borrell, A, Pesarrodona, A, Puerto, B, et al. Ultrasound diagnostic features of twin reversed arterial perfusion sequence. Prenat Diagn 1990;10:443–8.Google Scholar

Langlotz, H, Sauerbrei, E, Murray, S. Transvaginal Doppler sonographic diagnosis of an acardiac twin at 12 weeks gestation. J Ultrasound Med 1991;10:175–9.Google Scholar

Stiller, RJ, Romero, R, Pace, S, Hobbins, JC. Prenatal identification of twin reversed arterial perfusion syndrome in the first trimester. Am J Obstet Gynecol 1989;160:1194–6.Google Scholar

Pretorius, DH, Leopold, GR, Moore, TR, Benirschke, K, Sivo, JJ. Acardiac twin. Report of Doppler sonography. J Ultrasound Med 1988;7:413–16.Google Scholar

Benson, CB, Bieber, FR, Genest, DR, Doubilet, PM. Doppler demonstration of reversed umbilical blood flow in an acardiac twin. J Clin Ultrasound 1989;17:291–5.Google Scholar

Coulam, CB, Wright, G. First trimester diagnosis of acardiac twins. Early Pregnancy 2000;4:261–70.Google Scholar

Gembruch, U, Viski, S, Bagamery, K, Berg, C, Germer, U. Twin reversed arterial perfusion sequence in twin-to-twin transfusion syndrome after the death of the donor co-twin in the second trimester. Ultrasound Obstet Gynecol 2001;17:153–6.Google Scholar

Kamitomo, M, Kouno, S, Ibuka, K, et al. First-trimester findings associated with twin reversed arterial perfusion sequence. Fetal Diagn Ther 2004;19:187–90.Google Scholar

Cox, M, Murphy, K, Ryan, G, et al. Spontaneous cessation of umbilical blood flow in the acardiac fetus of a twin pregnancy. Prenat Diagn 1992;12:689–93.Google Scholar

Tan, TYT, Sepulveda, W. Acardiac twin: a systematic review of minimally invasive treatment modalities. Ultrasound Obstet Gynecol 2003;22:409–19.Google Scholar

Goh, A, Loke, HL, Tan, KW. The ‘TRAP’ sequence – life threatening consequences to the pump twin. Singapore Med J 1994;35:329–31.Google Scholar

Sullivan, AE, Varner, MW, Ball, RH, Jackson, M, Silver, RM. The management of acardiac twins: a conservative approach. Am J Obstet Gynecol 2003;189:1310–13.Google Scholar

Dashe, JS, Fernandez, CO, Twickler, DM. Utility of Doppler velocimetry in predicting outcome in twin reversed-arterial perfusion sequence. Am J Obstet Gynecol 2001;185:135–9.Google Scholar

Brassard, M, Fouron, JC, Leduc, L, Grignon, A, Proulx, F. Prognostic markers in twin pregnancies with an acardiac fetus. Obstet Gynecol 1999;94:409–14.Google Scholar

Sepulveda, W, Sebire, NJ. Acardiac twin: too many invasive treatment options – the problem and not the solution. Ultrasound Obstet Gynecol 2004;24:387–9.Google Scholar

Book contents

Chapter 12.1 - Twin reversed arterial perfusion (TRAP) sequence

Summary

Keywords

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References

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