Long-term follow-up after staged reconstruction or transplantation for patients with functionally univentricular heart

Decreased exercise performance with age in children with hypoplastic left heart syndrome

OBJECTIVE

Children born with hypoplastic left heart syndrome (HLHS) may experience cardiac dysfunction after staged surgery or transplantation, which may worsen with age. We examined the hypothesis that exercise testing can address cardiovascular capacity and suggest interventions to improve quality of life.

STUDY DESIGN

Children with HLHS > or = 8 years old performed treadmill or bicycle ergometric testing at 4 centers. Results were compared with norms for age and sex.

RESULTS

Of the 42 participants, the mean age was 12.9 years (range, 8.5-17.0 years), 64% were boys, 20 had staged surgery, and 34 completed metabolic assessment. The percent of predicted maximal oxygen uptake (mVO2) was higher in younger children. Children aged 8 to 12 years achieved 70% of predicted mVO2; children aged 13 to 17 years achieved 60% of predicted mVO2 (P = .02). The percent of predicted peak heart rate trended higher in younger patients (83% versus 75%, P = .07). Electrocardiographic changes were more common in older children. In treadmill testing, patients who had a transplant had better exercise performance than patients who underwent staged surgery in percent of predicted exercise time (82% versus 54%, P < .0001) and peak rate-pressure product (241 x 10(3) versus 195 x 10(3), P = .02). The percent of predicted mVO2 did not differ between patients who had a transplant (66%) and patients who underwent staged surgery (61%, P = .25).

CONCLUSION

Children with HLHS showed considerable age-related decline in exercise performance, regardless of surgical strategy.

Hypoplastic left heart syndrome

Hypoplastic left heart syndrome(HLHS) refers to the abnormal development of the left-sided cardiac structures, resulting in obstruction to blood flow from the left ventricular outflow tract. In addition, the syndrome includes underdevelopment of the left ventricle, aorta, and aortic arch, as well as mitral atresia or stenosis. HLHS has been reported to occur in approximately 0.016 to 0.036% of all live births. Newborn infants with the condition generally are born at full term and initially appear healthy. As the arterial duct closes, the systemic perfusion becomes decreased, resulting in hypoxemia, acidosis, and shock. Usually, no heart murmur, or a non-specific heart murmur, may be detected. The second heart sound is loud and single because of aortic atresia. Often the liver is enlarged secondary to congestive heart failure. The embryologic cause of the disease, as in the case of most congenital cardiac defects, is not fully known. The most useful diagnostic modality is the echocardiogram. The syndrome can be diagnosed by fetal echocardiography between 18 and 22 weeks of gestation. Differential diagnosis includes other left-sided obstructive lesions where the systemic circulation is dependent on ductal flow (critical aortic stenosis, coarctation of the aorta, interrupted aortic arch). Children with the syndrome require surgery as neonates, as they have duct-dependent systemic circulation. Currently, there are two major modalities, primary cardiac transplantation or a series of staged functionally univentricular palliations. The treatment chosen is dependent on the preference of the institution, its experience, and also preference. Although survival following initial surgical intervention has improved significantly over the last 20 years, significant mortality and morbidity are present for both surgical strategies. As a result pediatric cardiologists continue to be challenged by discussions with families regarding initial decision relative to treatment, and long-term prognosis as information on long-term survival and quality of life for those born with the syndrome is limited.

Hypoplastic left heart syndrome: attitudes among pediatric residents and nurses towards fetal and neonatal management

OBJECTIVE

To determine the attitudes of pediatric residents and nurses towards fetal/neonatal management of hypoplastic left heart syndrome (HLHS), and their basis.

METHODS

Pediatric residents and nurses from three cardiac centers completed a survey with hypothetical scenarios in which their own fetuses or newborns had HLHS. While Institution A performs many HLHS surgeries, Institution C performs very few.

RESULTS

A total of 43% of residents and 50% of nurses would terminate an affected pregnancy. More experience (4 to 7 years, p = 0.04; >7 years, p = 0.05) and employment at institution C (p = 0.04) predicted termination. Expected better quality of life (QOL) (p = 0.02) and five-year survival >50% (p = 0.06) predicted not terminating. Postnatally, 48% of residents and 68% of nurses would choose, or seriously consider, comfort care. Marriage (p = 0.04) and more experience (4 to 7 years, p = 0.04; >7 years, p = 0.02) predicted choosing comfort care. Asian/Pacific Islander descent (p = 0.01) and expected 5-year survival >50% (p = 0.02) predicted choosing surgery.

CONCLUSIONS

Approximately one-half of the pediatric residents and nurses surveyed would choose termination of pregnancy or seriously consider declining neonatal surgery, if their own fetus or infant had HLHS. These attitudes reflect perceptions of long-term QOL and survival. These attitudes may be of interest to caregivers who care for HLHS patients.