In the recent era, no congenital heart defect has undergone a more dramatic change in diagnostic approach, management, and outcomes than hypoplastic left heart syndrome (HLHS). During this time, survival to the age of 5 years (including Fontan) has ranged from 50% to 69%, but current expectations are that 70% of newborns born today with HLHS may reach adulthood. Although the 3-stage treatment approach to HLHS is now well founded, there is significant variation among centers. In this white paper, we present the current state of the art in our understanding and treatment of HLHS during the stages of care: 1) pre-Stage I: fetal and neonatal assessment and management; 2) Stage I: perioperative care, interstage monitoring, and management strategies; 3) Stage II: surgeries; 4) Stage III: Fontan surgery; and 5) long-term follow-up. Issues surrounding the genetics of HLHS, developmental outcomes, and quality of life are addressed in addition to the many other considerations for caring for this group of complex patients.

Because most medications for pediatric pulmonary hypertension (PH) are used off label and based on adult trials, little information is available on pediatric-specific adverse events (AEs). Although drug manufacturers are required to submit postmarket AE reports to the Food and Drug Administration (FDA), this information is rarely transmitted to practitioners. In the setting of a recent FDA warning for sildenafil, the authors sought to give a better description of the AEs associated with current therapies in pediatric PH. In January 2010, a written request was made to the Food and Drug Administration for AE records of commonly used PH medications. Reports were screened for pediatric patients, analyzed in terms of AEs, and compared with the medical literature. Arbitrarily, AEs that could be attributed to concomitant medications were not attributed to the PH medication in question. Adverse events occurring in more than 5 % of events for each drug were assumed to be associated with the targeted PH medication. Between November 1997 and December 2009, 588 pediatric AE reports (death in 257 cases) were reported for the three most commonly used therapies: bosentan, epoprostenol, and sildenafil. Many of the AEs were similar to those reported previously. However, 27 AEs not previously reported in the literature (e.g., pulmonary hemorrhage, hemoptysis, and pneumonia) were found. The FDA postmarket records for PH medications in pediatric patients show a significant number of AEs. The discovery of AEs not previously reported will better inform those caring for these complex and critically ill children, and the large number of deaths suggest they may be underreported in current literature.

Pulmonary arterial hypertension (PAH) causes changes in the right ventricle (RV), affecting RV size and function, ultimately leading to death. These changes have been evaluated by cardiac MRI (CMR) in adults with PAH, but not in children. Using CMR in pediatric patients with PAH, we examined how RV size and function (1) compare to normal data, (2) change over time, and (3) compare to similar studies in the adult population. Data from two institutions were retrospectively reviewed. Subjects with PAH and a CMR were included. Baseline CMR variables (right and left ventricular end-diastolic and end-systolic volumes indexed for body surface area, and calculated stroke volume and ejection fraction) were compared to normative data and follow-up CMR data. Twenty-six subjects (15 female), age 2-16 (mean 11) years, with idiopathic PAH were included. All patients were on PAH medication, and 65% on prostacyclin therapy. The baseline 6-Minute Walk Distance (6MWD; 481 ± 137) was normal. RV volumes and ejection fraction were markedly abnormal compared to normal data (P < 0.001). Follow-up CMRs were analyzed in 15 patients. RV volumes and function and LV stroke volume showed no significant change over one year. Our pediatric patients with PAH have markedly abnormal right ventricles by CMR but have normal walk distances. The lack of change in CMR parameters over one year may represent a stable cohort and is different than similar studies in adults.