Gynaecology & Obstetrics Which of the following is true in twin – reversed – arterial perfusion (TRAP) sequence A It is caused by a large arteriovenous placental shunt. B Donor is at risk of cardiomegaly and high output heart failure. C Most effective treatment is injection of KCI into recipient twin. D Placental arterial perfusion pressure in the recipient exceeds that of the donor. 💡 Explanation Which of the following is true in twin - reversed - arterial perfusion (TRAP) sequence ✓ Correct Answer: B. Donor is at risk of cardiomegaly and high output heart failure.