Intrafetal Alcohol Chemosclerosis of Acardiac Twins: A Multicenter Experience

Abstract

Objective: To report a multicenter experience with intrafetal alcohol chemosclerosis in the treatment of pregnancies complicated with the twin reversed arterial perfusion sequence. Methods: Percutaneous injection of 1– 2 ml of absolute alcohol into the intra-abdominal segment of the single umbilical artery was performed in 8 acardiac twins. Cases were collected from 5 centers following a standardized protocol. The procedure was performed under continuous ultrasound control, using color Doppler ultrasound to identify the main arterial vessel entering the abdomen of the acardiac twin and passing a 20-gauge spinal needle into the targeted vessel. Intraoperative and short-term complications were noted. Information on pregnancy outcome was obtained by reviewing the medical records or contacting the referring obstetrician. Result: At the time of the procedure, the acardiac twin was severely hydropic and the size exceeded 70% of the size of the pump twin in all cases. In addition, there were associated complications in all the pump twins including polyhydramnios in 8 cases (100%), cardiac insufficiency in 5 (63%), and fetal growth restriction in 1 (13%). The procedure was performed at a mean gestational age of 24.7 weeks (range 20–32), and it was technically successful in all cases. However, it was complicated with thrombosis of the umbilical vessels of the pump twin in 1 case, and transient bradycardia in 2 others. These 3 pump twins died in utero as a result of the procedure. The other 5 procedures were technically and clinically successful, resulting in an overall survival rate of 63%. In 4 pregnancies, the pump twin was delivered after 35 weeks and had no neonatal complications. Conclusions: Intrafetal alcohol chemosclerosis is a simple procedure that can be performed in any fetal medicine center around the world to stop the vascular supply to acardiac twins. However, the main concern with this technique is intravascular transfer of the ablative material to the circulation of the pump twin. The use of this technique should therefore be restricted to those pregnancies with poor prognostic factors and in countries where more sophisticated methods for the treatment of this condition are not available.

Optimal Method and Timing of Intrauterine Intervention in Twin Reversed Arterial Perfusion Sequence: Case Study and Meta-Analysis

“…Early attempts were highly invasive and involved hysterotomy and removal of the acardiac twin [2,3,4]. Subsequently, a series of other less invasive intrauterine interventions aiming to arrest the circulation of the acardiac twin were introduced [5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75]. These included insertion of cord coils, ligation with or without transection of the umbilical cord, endoscopic laser coagulation of placental anastomoses between the pump and acardiac twins, endoscopic laser coagulation and endoscopic or ultrasound-guided monopolar or bipolar diathermy of vessels within the cord supplying the acardiac twin and, more recently, ultrasound-guided ablation of intrafetal vessels by injection of alcohol, monopolar diathermy, laser or radiofrequency.…”

Radiofrequency Ablation for Selective Reduction in Complicated Monochorionic Multiple Pregnancies

“…For singleton pregnancies or dichorionic pregnancies, feticide can easily be achieved by fetal intracardiac potassium chloride injection. However, this method is not suitable for MC pregnancies because of the inevitable presence of vascular anastomosis in the MC placentas which can cause acute transfusion from the co-twin to the dying twin through these connecting circulations [7]. Death of one twin in an MC pair can result in death of or neurologic abnormality in the co-twin in 12 and 18% of cases, respectively [8].…”

Intrafetal alcohol ablation of an acardiac twin

“…Reported complications include death of the cotwin due to vascular thrombosis in the pump twin and failure to obliterate the target vessel despite using massive amount of alcohol. 20,21 In our case, the intervention was deemed necessary when the parasitic twin grew rapidly and the procedure was completed without any complication to the mother and the normal twin. We believe, correct identification of the artery using the colour flow mode (with or without spectral doppler), careful puncture of the vessel and choosing the injection site close to the cord attachment (thereby increasing the intravascular distant from the pump twin) could reduce the risk to the normal fetus.…”