Two Carolinas HealthCare System physicians have earned international acclaim following the successful completion of a new procedure in utero. Courtney Stephenson, DO, FACOG, director of the Charlotte Fetal Care Center and associate director of maternal and fetal medicine, and David Iannitti, MD, chief of hepato-biliary and pancreatic (HPB) surgery, are the first physicians in the world to treat a twin reversal arterial perfusion (TRAP) sequence pregnancy by using microwave ablation.
TRAP sequence is an extremely rare complication that occurs in approximately 1 percent of twins who share a placenta. In TRAP sequence pregnancy, one twin is physically normal, while the other is an abnormal mass of tissue, generally consisting of legs and a lower body but no upper body, head or heart. Because there is no heart, the term “acardiac twin” is used to define the mass.
Without a beating heart, the acardiac twin does not send or receive blood to any portion of the placenta. The “pump” twin has the extra work of sending and receiving blood to the acardiac mass as well as to its own developing tissues. As a result, the pump twin has a much higher level of exertion, which often results in heart failure. Without medical intervention, the pump twin is likely to die in utero or shortly after birth.
In most cases, intervention in pregnancies with TRAP sequence is limited to radio-frequency ablation (RFA). Dr. Stephenson tapped System-expert Dr. Iannitti to assist with the technique.
David Iannitti, MD
“The use of microwave energy in surgery is relatively new. In fact, it had never been used in pregnancy,” Dr. Iannitti said. “With the traditional RFA, by its design and nature, heat can be lost downstream. If attempting to separate vessels between fetuses, this heat loss can travel in the vessel and literally “heat up” the normal twin which we are trying to save.”
As a result, there have been many reports of fetal loss of the healthy twin immediately post-procedure using radio-frequency, and the obstetrical community never fully understood why.
“Dr. Iannitti has solved this problem,” Dr. Stephenson said. “Now we have a solution that markedly improves fetal-patient safety by avoiding injury to the innocent fetal bystander.” As a result of their partnership, Drs. Stephenson and Iannitti used microwave ablation to treat a TRAP sequence pregnancy in February 2012.
The patient was a pregnant 23-year-old woman expecting triplets. One of the triplets developed without a heart and was drawing the blood supply from one of the other fetuses. Without intervention, all of the fetuses would have died. Drs. Stephenson and Iannitti determined this was a case that would best be served by microwave ablation. The procedure, performed at Carolinas Medical Center, was a success, and the twins were saved.
Through extensive research and analysis, Dr. Stephenson can confidently say that microwave ablation is safe, effective and superior to other techniques for treating TRAP.
“It takes tremendous courage to push the forefront of obstetrics and advance maternal-fetal care. Lives are clearly on the line, and we are touching the “untouchable:” the intrauterine fetal environment,” Dr. Stephenson said.
Courtney Stephenson, DO, FACOG, treating a TRAP sequence pregnancy with microwave ablation.
In recognition of her accomplishment, Dr. Stephenson was selected to present her abstracts for the International Fetal Medicine and Surgery Society in Jerusalem this past May. One presentation was delivered in collaboration with Dr. Iannitti, who discussed the technique of microwave ablation. A second discussion focused on how both physicians launched a unique fetal care center with United States-based training. Their presentations were received with overwhelming praise from world experts in fetal surgery.
Both Drs. Stephenson and Iannitti believe microwave ablation is the most effective treatment for TRAP sequence and will continue to develop the procedure and share their knowledge with others in the medical community.
“I believe the rest of the world is investigating obtaining microwave antennae for their hospital systems as a result of our presentation. A very thoughtful and interesting conversation was provoked by the sharing of our work, and other centers are following our lead,” Dr. Stephenson said.
The Charlotte Fetal Care Center is part of the Maternal-Fetal Medicine Division at CMC-Women's Institute. The specialists work closely with pediatric and neonatal specialists at Levine Children's Hospital.