UCSF Medical Center | Inside Surgery | Pediatric Heart Surgery

Under the direction of Tom Karl, M.D., UCSF Children's Hospital enjoys an outstanding reputation for repairing complex heart defects in young children. Karl, who came to UCSF four years ago from the Royal Children's Hospital in Melbourne, Australia, heads a team of surgeons that includes Anthony Azakie, M.D., and Gary Raff, M.D. Karl has restructured the program to emphasize the multidisciplinary teamwork needed for the care of young heart patients as well as for adults with congenital cardiac abnormalities.

An eight-bed, freestanding Pediatric Cardiac Intensive Care Unit with an adjacent eight-bed monitored step-down unit was established in 2002. A pediatric intensivist, Ian Adatia, M.D., was recently recruited to direct the unit, which has its own nursing staff.

Other innovations include a new extracorporeal life support system specifically designed for rapid deployment in children with heart or lung problems. Unlike traditional extracorporeal membrane oxygenation (ECMO), this system is easy to set up, portable and available at all times in the Pediatric Cardiac Intensive Care Unit.

Surgical and non-surgical UCSF specialists who work with pediatric cardiac patients are unified within the newly established Pediatric Heart Center. For the past three years, the center has hosted an annual symposium featuring international speakers, which provides Northern California specialists with a free update on pediatric cardiology and surgery.

UCSF and UC Davis have established a joint, state-of-the-art Pediatric Heart Center in Sacramento, which combines the expertise of surgeons, cardiologists and other cardiac experts at both institutions. UCSF pediatric cardiac surgeon Gary Raff, M.D., coordinates this program.

Repair of hypoplastic left heart syndrome (HLHS) requires one of the most complicated surgical techniques in pediatric heart surgery. Treating this entity is a specialty of the UCSF team. As now performed at UCSF Children's Hospital, the three-stage surgical program required for HLHS brings techniques Karl developed in Australia to UCSF.

The initial surgery is performed within days of birth. A second surgery takes place about six months later and the final operation occurs by the time the child is 3-1/2 years old. Early outcome at UCSF is exceptionally good by international standards, and concern has shifted to longer-term neurodevelopmental issues.

Karl has built an international reputation for surgical treatment of this challenging heart anomaly — transposition of the great arteries. Surgery is performed in a single operation shortly after birth. Although transposition has a lethal natural history, with appropriate treatment a child can lead a nearly normal life.

UCSF pediatric surgeons use a variety of techniques to minimize complications from other types of heart surgery. An example is repair of pulmonary venous disease using only sutures outside the veins on the surface of the heart to avoid scarring and late venous obstruction. Some heart defects can be repaired using mini sternotomies of 3 to 4 centimeters, improving cosmetic results in the long term. The team also has developed ways to preserve heart valves and ventricular muscle in surgical repair of tetralogy of Fallot and Marfan syndromes. Historically, prosthetic valves have been necessary to correct some of these conditions. The currently used techniques incorporate native valve tissue in a plastic surgical repair that usually results in a competent valve.

Under Azakie, UCSF Children's Hospital is researching the molecular biology of myocardial development, studying which genetic factors trigger differentiation of cells during the prenatal period. "Our aim is to use that information to bioengineer cardiac myoblasts for use in cell-based therapies for heart failure," Azakie said. Heart failure affects 400,000 to 500,000 Americans each year. Cell-based therapies are becoming technically feasible, but the optimal cell type for cell-based treatment of heart failure has not yet been determined. Azakie's team is looking at cardiac-specific transcription factors that operate during cell differentiation. They are also interested in characterizing genetic defects associated with certain heart problems.

In the clinical arena, pediatric surgeons are conducting collaborative studies of ways to minimize brain injury in neonates before, during and after cardiac surgery. "We expect children to survive the surgery and we're focusing on long-term neurodevelopmental outcomes," Karl said. Instead of deep hypothermic circulatory arrest, surgeons now use selective cerebral perfusion during cardiopulmonary bypass.

Brain oxygenation is monitored continuously during surgery to determine which flow rates and temperatures maximize oxygenation while minimizing the risk of neurological damage. Surgeons are also looking at blood markers, such as brain natriuretic peptide that may signal a baby is at risk for complications during the perioperative period.

The issue of neurological injury is complex, however. A recent study from UCSF of infants with transposition of the great arteries suggested that brain injury often occurs preoperatively in these babies as a result of the heart deformity.

UCSF pediatric cardiac surgeons regularly bring their expertise to parts of the world where life-saving heart surgery is not otherwise available. Karl is a director of the International Child Heart Foundation and regularly travels to Managua, Nicaragua on medical missions. Others from UCSF, including cardiologists, respiratory therapists and pediatric intensive care nurses, have accompanied him on some of these trips. UCSF surgeon Raff has traveled on behalf of the group to Samara, Russia.