Cardiac anomalies, including right ventricular outflow tract obstruction (RVOTO) or twin circular intracardiac shunt typically affect recipient twin. Interestingly, in our case the donor was affected.
Laser intervention at an early stage of TTTS associated with a significant reduction in the incidence of RVOTO. A prediction model for the risk of RVOTO at birth in TTTS recipients was constructed - abnormal flow in the DV, pericardial effusion and early gestational age at onset of TTTS are predictors of RVOTO in TTTS recipients (Eschbach SJ et al., 2017), [2].
RVOTO can develop after laser treatment or even in the neonatal period and in all Quintero stages (Eschbach SJ et al., 2018), [3].
Donor twin is rarely affected by the RVOTO and the pathomechanism of this phenomenon in donor twin is still not fully clarified.
References
1. Pruetz JD, Votava-Smith JK, Chmait HR, Korst LM, Llanes A, Chmait RH. Recipient Twin Circular Shunt Physiology Before Fetal Laser Surgery: Survival and Risks for Postnatal Right Ventricular Outflow Tract Obstruction. J Ultrasound Med. 2017 Aug;36(8):1595-1605. doi: 10.7863/ultra.16.08038. Epub 2017 Apr 3. PubMed PMID: 28370096
2. Eschbach SJ, Boons LSTM, Van Zwet E, Middeldorp JM, Klumper FJCM, Lopriore E, Teunissen AKK, Rijlaarsdam ME, Oepkes D, Ten Harkel ADJ, Haak MC. Right ventricular outflow tract obstruction in complicated monochorionic twin pregnancy. Ultrasound Obstet Gynecol. 2017 Jun;49(6):737-743. doi: 10.1002/uog.16008. Epub 2017 May 2. PubMed PMID: 27363529.
3. Eschbach SJ, Ten Harkel ADJ, Middeldorp JM, Klumper FJCM, Oepkes D, Lopriore E, Haak MC. Acquired right ventricular outflow tract obstruction in twin-to-twin transfusion syndrome; a prospective longitudinal study. Prenat Diagn. 2018 Dec;38(13):1013-1019. doi: 10.1002/pd.5378. Epub 2018 Nov 28. PubMed PMID: 30365169.