twin-twin transfusion syndrome - lieberman's...

Twin-twin transfusion syndrome

Michael Honigberg, HMS III

Gillian Lieberman, MD

March 2012

Michael Honigberg, HMS3




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Understand the cause and consequences of twin-twin transfusion syndrome

Recognize the key diagnostic findings of twin-twin transfusion syndrome on ultrasound

Learn about management options for twin-twin transfusion syndrome

Objectives



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Early embryology: cell division in the Fallopian tube

http://www.patana.ac.th/secondary/science/IBtopics/IB%20Human(05)/pages/5.7.htm



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Early embryology: cell division in the Fallopian tube

http://www.patana.ac.th/secondary/science/IBtopics/IB%20Human(05)/pages/5.7.htm

Fimbriae

Infundibulum

Ampulla

Isthmus Interstitium



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Embryology of monozygotic twinning

Days 1-3 (morula)

Dichorionic diamniotic

~30% of monozygotic twin pregnancies

Days 4-8 (blastocyst)

Monochorionic diamniotic


Days 8-12 (implanted blastocyst)

Monochorionic monoamniotic


Days 13+ (formed embryonic disc)

Conjoined twins Rare

Images from http://en.wikipedia.org/wiki/File:Placentation.svg



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Complications of multiple gestation

General – Preterm delivery – Placental abruption – Growth abnormalities (e.g., IUGR, SGA) – 2-3x increased risk of preeclampsia, gestational

diabetes

Monochorionic diamniotic – Twin-twin transfusion syndrome – Twin reversed arterial perfusion – Twin anemia-polycythemia sequence

Monochorinoic monoamniotic – Cord entanglement



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Our patient

37-year-old G2P1001 with twin gestation at 17w 2d, here for second opinion about “low amniotic fluid”

Reports active fetal movement, no loss of fluid or vaginal bleeding

Prenatal course previously uncomplicated

How should we image her twins?



Menu of tests for fetal imaging

Ultrasound

MRI

– Indications: Assessment of fetal CNS, fetal anomalies, placental anomalies (e.g., accreta)

– Safety studies have been performed at 1.5T

– Gadolinium not recommended (crosses placenta and remains in amniotic fluid)

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Our patient’s ultrasound: Twins A and B in sagittal view

PACS, BIDMC

Continue to view labeled images



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Our patient’s ultrasound: Labeled images

Uterus

Maxilla

Mandible

Anterior abdominal wall

Spine Umbilical cord

Uterus

PACS, BIDMC



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Our patient’s ultrasound: Discrepant amniotic fluid volumes

Anechoic amniotic fluid

PACS, BIDMC



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Concordant growth, but…

“The considerable discrepancy in amniotic fluid volumes suggests early appearance of twin-to-twin transfusion syndrome.”

Summary of ultrasound findings



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Twin-twin transfusion syndrome (TTTS)

Unbalanced blood flow through placental anastamoses from “donor” to “recipient,” possibly leading to hydrops, fetal death

Up to 20% of mono/di pregnancies (i.e., up to 4% of all twin pregnancies)

Responsible for 15-20% of total perinatal mortality in twins

Most commonly develops at 20-21 weeks – Can develop in 1st and 3rd trimesters

Acute onset in most cases

Cincotta and Fisk; Callen



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Pathophysiology of TTTS

Monochorionic placentas normally have multiple vascular connections

AA and VV are bidirectional while AV are unidirectional

“Classic” TTTS placenta: Single unidirectional AV anastamosis without compensatory AA/VV connections

Normal

TTTS

Modified from Cincotta and Fisk, Clin Obstet and Gynecol. 1997



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http://www.texaschildrens.org/carecenters/fetalsurgery/twin_twin_transfusion_syndrome.aspx

Placental anastamoses

AA/VV anastamoses are superficial

AV are deep

Courtesy Janneth Romero, MD

Anastamosis



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Pathophysiology of TTTS, continued

Increased blood flow to the recipient increased renal perfusion and increased ANP polyuria

Hypovolemia in the donor decreased renal perfusion increased ADH oliguria

Why doesn’t increased systemic pressure in the recipient halt shunting?

– Donor placental vascular vasoconstriction helps maintain pressure gradient

– Global fetoplacental vascular derangement

Galea, Jain, and Fisk



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Companion patient #1: TTTS on ultrasound

http://www.bwhct.nhs.uk/fetalmedicine-home/fmc-procedures/fmc-tts.htm



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Companion patient #1: TTTS on ultrasound, labeled

http://www.bwhct.nhs.uk/fetalmedicine-home/fmc-procedures/fmc-tts.htm

Amniotic membrane

Oligohydramnios Polyhydramnios

Fetal hand

Fetal arm



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Diagnosis of TTTS

Demonstration of polyhydramnios/oligohydramnios sequence

– Polyhydramnios: Maximum vertical fluid pocket > 8 cm before 20 weeks, > 10 cm after 20 weeks

– Oligohydramnios: Maximum vertical fluid pocket < 2 cm

Monochorionic placentation

Fetuses of the same sex

(Usually fetal size discordance > 20%)



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Differential diagnosis of TTTS

Genitourinary tract abnormality in oligohydramniotic twin

Isolated IUGR of one fetus (if growth discrepancy < 15%)

Dichorionic twin pregnancy with fused placentas and growth restriction of one fetus



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TTTS staging: Quintero scale

I: Poly/oligohydramnios

II: “Absent bladder” in donor

III: Abnormal Doppler

IV: Hydrops

V: Demise

– Thought to reflect typical disease progression

– Appears to correlate with prognosis in patients undergoing treatment

Quintero et al., J. Peritnatol 1999

Survival in patients treated with laser photocoagulation of the communicating vessels



Let’s view several ultrasounds, applying the Quintero stages.



Companion patient #2: Evaluation of the fetal bladder (Stage II)

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http://www.fetalultrasound.com/online/text/9-092.htm

Umbilical arteries

Bladder (normal)

“Absent” bladder



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Fetal circulation

Image from Up-to-Date



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Normal fetal Doppler evaluation Umbilical artery waveform

should always be antegrade

Ductus venosus has the highest-velocity flow in the fetal venous system and should also be antegrade throughout the cycle – Absent/reversed waveform in

DV always abnormal

– Flow reversal in atrial systole normal in IVC/SVC

Umbilical vein flow should be non-pulsatile

Images from Up-to-Date

Peak systolic flow

End-diastolic

flow

Systolic peak

Diastolic peak

Atrial systole



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Doppler evaluation of TTTS: Findings in Stage III

Normal TTTS

Umbilical artery

Ductus venosus

Umbilical vein

Donor UA shows absent end-

diastolic flow1

Recipient DV shows flow

reversal in atrial systole2

Pulsatile recipient UV3

1Kim et al.; 2Wee and Fisk; 3http://www.centrus.com.br/DiplomaFMF/SeriesFMF/doppler/capitulos-html/chapter_11.htm



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Companion patient #3: “Stuck twin” on MRI and Doppler US

Courtesy Deborah Levine, MD



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Companion patient #3: “Stuck twin” on MRI and Doppler US, labeled

Courtesy Deborah Levine, MD

Absent end-diastolic flow in the umbilical

artery

T2 MRI

Coronal view of “stuck twin”

(donor)

Enlarged ventricles

Sagittal view of recipient

Lateral ventricle

Arm



Companion patient #4: Fetal hydrops (Stage IV) on US

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Femur

Courtesy Carolynn DeBenedectis, MD

Massive skin and

soft tissue edema

Ascites

Pleural and pericardial effusions

Polyhydramnios

Skin edema (late finding)



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Companion patient #5: Progression of TTTS on US, recipient fetus, sagittal view

20w 0d 21w 3d 24w 3d




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Companion patient #5: Polyhydramnios in TTTS on 20w US, sagittal view, labeled

20w 0d 21w 3d 24w 3d


Leg Abdomen Head



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Companion patient #5: Progressive hydrops with fetal ascites at 24w3d on US, recipient fetus on sagittal view

20w 0d 21w 3d 24w 3d


Ascites Worsening

ascites

Hepatomegaly



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Complications of TTTS

Polyhydramnios uterine distention respiratory/abdominal discomfort, (PP)ROM, preterm labor, abruption

Fetal cardiac complications, especially the recipient: – Heart failure leading to hydrops – Cardiomyopathy – Mitral and/or tricuspid regurgitation – Right ventricular outflow tract obstruction (8%)1

Pulmonary hypoplasia (donor) Anemia of donor, polycythemia of recipient

1Callen



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Complications of TTTS, continued

Demise of one or both twins – Exsanguination of surviving twin via AA/VV

anastamoses if present – Disseminated intravascular coagulation following

co-twin demise – Twin embolization syndrome

Neurologic and renal disease also common in survivors



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Options for managing TTTS

Laser photocoagulation of the placental vessels*

Amnioreduction – Reduces uterine distention and improves

placental perfusion – Often performed serially because underlying

abnormality persists – Complications: PPROM, chorio, abruption

Septostomy – Introduce connection in inter-twin membrane to

equalize volumes of amniotic fluid – Creation of monoamniotic sac risk of cord

entanglement



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Options for managing TTTS, continued

Expectant management – Stage I: 10-50% worsen – Stage II+: 70% perinatal mortality1

Selective termination – If one fetus abnormal or other measures fail – Laser coagulation – Bipolar forceps coagulation – Radiofrequency ablation

Delivery if past age of viability

1Berghella and Kaufmann



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Laser coagulation of placental vessels

Significantly better outcomes than other methods – Considered first-line but only

performed at specialized centers – 65-85% survival of at least one

twin, 35-50% of both1

Fetoscope introduced under U/S, placental equatorial plate visualized

Vessels mapped and selectively coagulated

Complications: – PPROM (17%) – Bleeding – Chorioamnionitis – Abruption

Images from Up-to-Date

Donor artery

Recipient vein

Laser

Post-ablation

1Chalouhi et al.



Let’s take a brief look at another related condition.



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Twin reversed arterial perfusion (TRAP)

Acardiac twin perfused by viable pump twin via AA anastamoses – 70% of acardiac masses have two-vessel cord,

suggesting underlying genetic abnormality

Diagnosis: Reversed umbilical artery flow in acardiac twin on Doppler – Lower half of acardiac twin develops because it

is perfused via the iliac arteries

Pump twin is at risk for heart failure and preterm birth



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Companion patient #6: TRAP, Twin A, axial view of the chest on US




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Companion patient #6: TRAP, Twin A, axial view of the chest on US, labeled


LA

RA

RV

LV Polyhydramnios



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Companion patient #6: TRAP, Twin B, axial view of the chest on US, labeled


Involuted cardiac mass



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Companion patient #6: TRAP, Twin B, axial view of the chest with Doppler


Reversal of flow in the umbilical artery



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Options for managing TRAP

Coagulation of acardiac twin cord and/or AA anastamosis – Laser coagulation – Bipolar forceps coagulation – Radiofrequency ablation

? Higher success and reduced complications with RFA

Expectant management – High risk of heart failure in pump twin (55%

perinatal mortality)

Delivery if past age of viability



Let’s return to our patient.



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Our patient: Clinical course continued

Declined fetal surgery, opted for reassessment in one week

One week later, reported increased abdominal pressure

In-office ultrasound showed Twin A with multiple amniotic fluid pockets >10 cm, Twin B with almost no amniotic fluid

Patient opted to wait one more week before deciding on treatment

One week later, returned for ultrasound



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Our patient: Repeat US at 19w 2d (Twin A, recipient)

PACS, BIDMC



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Our patient: Repeat US at 19w 2d (Twin A, recipient), labeled

Arm

Edematous skin consistent with

hydrops

Lack of Doppler activity within

the chest

PACS, BIDMC

Arm

Chest Pelvis



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Our patient: Repeat US at 19w 2d (Twin B, donor)

PACS, BIDMC



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Our patient: Repeat US at 19w 2d (Twin B, donor), labeled

Lack of Doppler activity within

the chest

M-mode: No heart beat

Diagnosis: Demise of both twins

PACS, BIDMC



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Summary

TTTS is a serious complication of monochorionic diamniotic pregnancy with high morbidity/mortality

Key diagnostic features are polyhydramnios/ oligohydramnios, absent donor fetal bladder, Doppler abnormalities, and hydrops

Management options include laser photocoagulation, amnioreduction, septostomy, selective termination, expectant, and delivery



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Acknowledgements

Carolynn DeBenedectis, MD

Deborah Levine, MD

Janneth Romero, MD

Joe Reardon, Grant Smith, Christian Strong

Claire Odom




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References

Baschat AA. Venous Doppler for fetal assessment. Up-to-Date.

Berghella V, Kaufmann M. Natural history of twin-twin transfusion syndrome. J Reprod Med. 2001;46(5):480.

Callen PW. Ultrasonography in Obstetrics and Gynecology. 5th edition. Saunders: Philadelphia, 2007.

Cincotta RB, Fisk NM. Current thoughts on twin-twin transfusion syndrome. Clin Obstet and Gynecol. 1997;40(2):290.

Galea R, Jain V, Fisk NM. Insights into the pathophysiology of twin-twin transfusion syndrome. Prenat Diagn 2005;25:777.

Holland MG, Mastrobattista JM, Lucas MJ. Diagnosis and management of twin reversed arterial perfusion (TRAP) sequence. Up-to-Date.

Kim JA, Cho JY, Lee YH, et al. Complications arising in twin pregnancy: Findings of prenatal ultrasonography. Korean J Radiol. 2003;4(1):54.

Moise KJ, Johnson A. Pathogenesis and diagnosis of twin-twin transfusion syndrome. Up-to-Date.

Moise KJ, Johnson A. Management of twin-twin transfusion syndrome. Up-to-Date.

Quintero RA, Morales WJ, Allen MH, et al. Staging of twin-twin transfusion syndrome. J Perinatol 1999;19(8):550.

Quintero RA, Comas C, Bornick PW, et al. Selective versus non-selective laser photocoagulation of placental vessels in twin-to-twin transfusion syndrome. Ultrasound Obstet Gyncol 2000;16:230.

Russell Z, Quintero RA, Kontopoulos EV. What is the definition of pulsatile umbilical venous flow in twin-twin transfusion syndrome? Am J Obstet Gynecol 2008;199:634.

Wee LY, Fisk NM. The twin-twin transfusion syndrome. Semin Neonataol 2002;7:187.

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