Pediatric Research

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Boston Children’s Hospital is constantly improving care. Some of these improvements are rooted in scientific research: Understanding diseases deeply—even at the cellular or molecular level—leads to new drugs and therapies.

But some improvements come from moments spent at the bedside, when clinicians see inadequate science or imperfect models of care. When this happens our staff often makes the effort to change things for the better, benefiting patients and the medical field at-large.


This approach, which we define as “clinical innovations,” requires clini­cians to think out of the box. In doing so they are free to develop new tools and inventive strategies. It's the path by which many major medical innovations and improvements in care have been made.

Innovations play a critical role in our transplant patients’ health, so our team is constantly creating new procedures, programs, tests, processes and tools. An innovation may be “small,” like finding a creative way to help a young patient take her medication on time. Or it may be a big discovery that changes the entire field of pediatric transplantation.

Read below to learn more about clinical innovations like the Berlin Heart, the STEP procedure and TESLA.


The Berlin Heart 

A number of Boston Children’s cardiologists and cardiovascular surgeons, including Francis Fynn-Thompson, MD, and Elizabeth Blume, MD, have researched, written about and implanted the Berlin Heart ventricular assist device. It's a machine that pumps blood in a person's body if their heart is unable to do so.


The device can pump blood from the heart to the lungs, where it becomes oxygenated, and from the heart to the rest of the body, where it supplies cells with oxygen and nutrients. Only the “delivery tubes” are implanted inside the body; the rest of the device operates on a rolling cart outside of the body.

The Berlin Heart is a life-saving bridge to transplant. In 2008, Boston Children’s became one of only 10 pediatric institutions in the United States to receive unconditional approval from the FDA for ongoing Investigational Device Exemption (IDE). That means our experts are trusted to implant and maintain the device for any child who needs it.

Read how the Berlin heart served as a bridge to 12-year-old Keenan’s transplant.


STEP procedure

In 2002, Heung Bae Kim, MD, director of the Pediatric Transplant Center, and surgeon Tom Jaksic, MD, PhD, became the first team to perform a serial transverse enteroplasty, or STEP procedure.

This procedure, devised by Dr. Kim, reshapes the small intestine of children with short bowel syndrome to create a longer and more narrow passageway for food to travel through, allowing the body to absorb nutrients.


  • In the STEP procedure, special devices are used to simultaneously cut and staple the bowel in a direction to correspond with the small intestine's blood supply.

  • Immediately after the STEP procedure, the small bowel has a "zigzag" appearance from these staple lines.

Since its invention, Boston Children's doctors have performed 19 STEP procedures with increasing success, establishing Boston Children's as one of the preeminent hospitals in the world for the treatment of short bowel syndrome.

STEP in the media:

This 2006 webcast features a STEP procedure performed live, with commentary from Dr. Kim and Dr. Jaksic.



Medical conditions like midaortic syndrome or renal artery stenosis cause a person's aorta and/or blood vessels to become too narrow or damaged, restricting proper blood flow to certain organs. In some cases the reduced blood flow can lead to kidney failure, eventually requiring a transplant.

Replacing narrow or damaged vessels with healthy blood vessels from other parts of the body can treat this problem, but there’s a catch: healthy vessels tend to be too short to adequately “fill in” for the vessels they are replacing. This is can be especially true in children.


In response, Boston Children’s Hospital Pediatric Transplant Center Director, Heung Bae Kim, MD, and his colleagues have pioneered a new technique called TESLA (Tissue Expander Stimulated Lengthening of Arteries). It works like this: first, surgeons place a tissue-expanding device behind the patient’s aorta.

The device is then filled with a saline solution over the course of several months, making it bigger and naturally stretching the aorta and its blood vessels over time. Once the aorta appears long enough, the surgical team removes the narrowed area and replaces it with pieces of the newly stretched vessels—eliminating the need for multiple, invasive surgical procedures, and possibly for transplantation, as well.

TESLA has already proven successful in one patient’s case, and is currently being used to treat other patients.


The future of pediatrics will be forged by thinking differently, breaking paradigms and joining together in a shared vision of tackling the toughest challenges before us.”
- Sandra L. Fenwick, President and CEO

Boston Children's Hospital 300 Longwood Avenue, Boston, MA 02115 617-355-6000 | 800-355-7944