TRAP sequence

Twin:twin reverse arterial perfusion (TRAP) sequence

A condition in which one fetus lacks a heart and the other fetus pumps the blood for both.
Mentioned in: Prenatal Surgery
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
The management of TRAP Sequence has been controversial due to the paucity of literature with many proposed methods loosely based on gestational age.
There is limited data in regard to the conservative management of TRAP Sequence for those patients diagnosed after 24 weeks of gestational age.
Several different techniques have been used to treat TRAP sequence by interrupting the connection between the acardiac twin and the pump twin to increase the chances that the pump twin will survive.
Utilizing RFA to treat TRAP sequence has been shown to be extremely effective.
INTRODUCTION: TRAP sequence is known as acardius or "chorioangiopagus parasiticus".
We report a case of primigravida with TRAP sequence.
Several theories had been postulated to explain TRAP sequence. The most accepted theory is that, artery-to-artery anastomosis between monochorionic twins in the first trimester is the fundamental event in the development of TRAP sequence.
First trimester discordance in these cases represent an early manifestation of TRAP sequence. (5) Color Doppler confirms TRAP sequence by showing reversal in the flow direction in umbilical artery of perfused twin, smaller resistive index (<0.2) is associated with poor outcome including cardiac failure and central nervous system hypoperfusion.
CONCLUSION: TRAP sequence although rare should be suspected in all monochorionic pregnancies.
TRAP sequence is a rare obstetric condition that occurs in 1% of monochorionic twin pregnancies and in 1: 35,000 of all pregnancies [9,10].
Acardiac twin or TRAP sequence is a rare complication of monochorionic twin pregnancies.1 Multiple pregnancy accounts for 1.5% of all pregnancies, acardiac twin incidence is 1 per 35,000 birth among 1% of monozygotic twins.
Among the fragments amplified with TRAP, 60 fragments were recycled and cloned into pMD19-T vector, Thirty-six sequences were obtained and then submitted to GenBank, The accession numbers of TRAP sequences were from KC906193 to KC906227 and KC906229.