Alexandra Lindsay of Rockville, Md., was no stranger to heart surgery. Born on Aug. 19, 2008, with tetrology of fallot and pulmonary atresia, congenital heart conditions preventing the normal amount of blood from being pumped into the lungs, she had her first operation at 3 days of age. Six weeks later during a routine cardiology visit, the oxygen saturation level in her blood was found to be extremely low. A follow-up echocardiogram showed she was in heart failure, which quickly progressed to cardiac arrest. She was immediately placed on ECMO, or Extra-Corporeal Membrane Oxygenation, which takes over the function of the heart and lungs. But ECMO would only buy time for Alexandra, who was now facing an even bigger operation.
“The doctors told us Ally would not leave the hospital without a new heart,” says her mother, Valerie Lindsay. “She would have to have transplant surgery.”
Though Hopkins Children’s, which has been doing heart transplants since 1983, has good overall survival rates, some patients never make it to the operating room. Up to 40 percent of infants on the waiting list for donor hearts die while they wait, with the average waiting time exceeding two months due to factors like finding a blood-type match. But serendipity in the form of pediatric cardiac surgeon Luca Vricella and Hopkins Children’s researchers played a hand in Ally’s case. He had recently led a study that found heart transplants among non-compatible blood groups in infants a year old or younger is as safe as transplants with compatible blood groups (The Journal of Heart and Lung Transplantation, October 2008; Vol. 27, Issue 10; pages 1085-1089).
“There was no difference in outcome between incompatible and compatible transplantation in these infants,” Vricella reported at the American Heart Association's annual Scientific Sessions in December 2007.
Vricella’s analysis was based on national data on infant heart transplants reported to UNOS, the United Network for Organ Sharing, from 1999 to 2007. Of 591 infants who underwent transplantation, 35 (6 percent) received hearts from ABO-incompatible donors. Two ABO-compatible infants died from transplant rejection, in which the transplant recipient’s immune system damages the donor organ, but no ABO- incompatible infants died from rejection. Survival in both groups reached 75 percent three years after transplantation.
Until age 12 to 14 months, Vricella explains, infants have immature immune systems that have produced little or no antibodies, known as isohemagglutinins, against a potential donor heart, lowering the risk of rejection. Using incompatible donor hearts, he says, could reduce by at least 20 percent the number of infants who die while on the waiting list to receive donor hearts. The findings meant that Ally was a candidate for so-called ABO-incompatible heart transplantation, which would increase her chances of obtaining a donor heart. On Dec. 24, 2008, she did, becoming Hopkins Children’s first ABO-incompatible heart transplant patient and giving what her mother calls “the greatest Christmas gift of all.”
So, how is Ally, now a one-year old, doing today?
“She’s really taken off,” says her mother. “She’s tiny but feisty, totally a fighter. She’s caught up developmentally, and she laughs a lot.”
Vricella concludes, “Ally shows that we can provide yet another aspect of care for heart failure patients.”
For more information about the pediatric heart failure program at Hopkins Children’s, call 443-287-1262.