P22.08: Persistent rudimentary cardiac activity of the perfused twin after radiofrequency ablation for twin reversed arterial perfusion sequence

Abstract

A-29-year-old women, 1 para, was admitted to our institute following the diagnosis of twin reversed arterial perfusion (TRAP) sequence at 17 weeks of gestational age. Color and pulsed Doppler examination demonstrated tiny rudimentary cardiac activity of approximately 90 beats per minute (BPM) in the acardiac twin as well as arterial blood flow perfusing the acardiac twin via arterioarterial anastomosis (AAA) and venous flow in venovenous anastomoses to the pump twin. The acardiac/pump twin size ratio was 76% and the pump twin was associated with tricuspid and mitral regurgitation, cardiomegaly and hepatomegaly due to cardiac failure. Radiofrequency ablation (RFA) was performed at 18 weeks of gestation. The patient provided written informed consent and the Institutional Review Board at the institute approved. Until a confirmation of the disappearance of blood flow to the acardiac twin using HD flow of Voluson E8 (GE Healthcare, Kretztechnik, Zipf, Austria), the procedures were repeated targeting to the artery in the acardiac twin. However, just after the procedure, tiny heart beats of approximately 90 BPM and to-and-fro blood flow at aorta and a vessel of the neck were detectable in the acardiac twin with HD flow aside from fetal heart rate of 150 BPM in the pump twin. Subsequently, cardiac activity of the acardiac twin still existed 5th days after the procedure. Persistent rudimentary heart beat of the acardiac twin should be distinguished from the rest of blood flow from the pump twin after RFA for TRAP sequence.