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The outcome of twin reversed arterial perfusion sequence diagnosed in the first trimester
Liesbeth Lewi1, Catalina Valencia, Esperanza Gonzalez
1Harris Birthright Research Centre for Fetal Medicine, King's College Hospital, London, UK.
Objective:
The aim of this study was to document the mortality of twin reversed arterial perfusion (TRAP) sequence from the first trimester to planned intervention at 16-18 weeks.
Study Design:
A retrospective review was performed of the outcome of monochorionic twin pregnancies diagnosed with twin reversed arterial perfusion sequence in the first trimester.
Results:
Twenty-six pregnancies were diagnosed with twin reversed arterial perfusion sequence in the first trimester: 2 opted for termination of pregnancy and 24 opted for prophylactic intervention to arrest the reversed flow, which was planned at 16-18 weeks. In 8 of 24 (33%) pregnancies, spontaneous death of the pump twin occurred between diagnosis and planned intervention. In 5 of 24 (21%), there was a spontaneous arrest of flow; whereas, in 11 (46%) there was persistent flow toward the acardiac twin at 16-18 weeks.
Conclusion:
Twin reversed arterial perfusion carries a high mortality between the first and early second trimester.
