Heart Transplantation in Children: Clinical Outcomes in a Single Center

Late outcome after paediatric heart transplantation in Finland

OBJECTIVES

We studied the long-term survival and rejection episodes of paediatric heart transplant recipients.

METHODS

We included all paediatric patients (≤18 years) who underwent heart transplantation during 1991-2014 in Finland. Data were obtained retrospectively from a paediatric cardiac surgery database. Patient status was received from the Finnish population registry. All patients underwent yearly routine postoperative endomyocardial biopsies and coronary angiographies.

RESULTS

Between 1991 and 2014, 68 heart transplantations were performed. The early mortality (<30 days after surgery) rate was 10% and follow-up coverage was 100%. The 10- and 15-year survival rates for all patients were 68% (95% confidence internal, CI, 56-80%) and 65% (95% CI 53-78%), respectively, including early mortality. The 1-year survival rate was 100% when excluding early operative mortality. Indications for heart transplantation were cardiomyopathy in 57% and cardiac malformations in 43% of patients, with similar long-term survival between the groups. During 23 years of follow-up, 43 patients (70%) had at least one rejection episode and 17 patients (29%) at least a grade 1 coronary artery vasculopathy finding. Patients with early rejection episodes (<3 months) had a higher incidence of late rejection episodes (P = 0.025). Older age at operation was a significant risk factor for the development of coronary artery vasculopathy (hazard ratio 1.1, 95% CI 1.0-1.3, P = 0.012).

CONCLUSIONS

First-year survival was excellent. Asymptomatic rejection episodes were common among patients. Early rejection episodes are a risk factor for late rejection episodes and show a trend towards an increased risk of late death. Coronary artery vasculopathy remains a major challenge for late graft survival.

Changes in Risk Profile Over Time in the Population of a Pediatric Heart Transplant Program

BACKGROUND

Single-center data on pediatric heart transplantation spanning long time frames is sparse. We attempted to analyze how risk profile and pediatric heart transplant survival outcomes at a large center changed over time.

METHODS

We divided 320 pediatric heart transplants done at Stanford University between 1974 and 2014 into three groups by era: the first 20 years (95 transplants), the subsequent 10 years (87 transplants), and the most recent 10 years (138 transplants). Differences in age at transplant, indication, mechanical support, and survival were analyzed.

RESULTS

Follow-up was 100% complete. Average age at time of transplantation was 10.4 years, 11.9 years, and 5.6 years in eras 1, 2, and 3, respectively. The percentage of infants who received transplants by era was 21%, 7%, and 18%, respectively. The indication of end-stage congenital heart disease vs cardiomyopathy was 24%, 22%, and 49%, respectively. Only 1 patient (1%) was on mechanical support at transplant in era 1 compared with 15% in era 2 and 30% in era 3. Overall survival was 72% at 5 years and 57% at 10 years. Long-term survival increased significantly with each subsequent era. Patients with cardiomyopathy generally had a survival advantage over those with congenital heart disease.

CONCLUSIONS

The risk profile of pediatric transplant patients in our institution has increased over time. In the last 10 years, median age has decreased and ventricular assist device support has increased dramatically. Transplantation for end-stage congenital heart disease is increasingly common. Despite this, long-term survival has significantly and consistently improved.

Cardiac Allograft Function During the First Year after Transplantation in Rejection-Free Children and Young Adults

Background—

Allograft dysfunction is a common finding early after heart transplant (HT). We sought to assess the recovery of left (LV) and right ventricular (RV) function during the first year after HT in children and young adults using pulsed-wave tissue Doppler imaging.

Methods and Results—

We analyzed serially performed echocardiography in 44 pediatric HT recipients (median age: 7.3 years at HT) who remained rejection-free during the first year post-transplant. Age-based normative values for systolic ( S ′), early-diastolic ( E ′), and late-diastolic ( A ′) velocities obtained using pulsed-wave tissue Doppler imaging in 380 healthy children were used to transform patient data into z scores. Pulsed-wave tissue Doppler imaging studies ≤10 days post-HT demonstrated biventricular systolic and diastolic dysfunction with most prominent impairment in RV systolic function ( S ′ z score −2.7±0.8), RV early-diastolic filling ( E ′ z score −2.3±1.1), and LV early-diastolic filling ( E ′ z score −2.3±1.1). LV systolic function ( S ′ z score) and late-diastolic filling ( A ′ z score) improved to normal in 11 to 30 days, LV early-diastolic filling ( E ′ z score) in 4 to 6 months, and RV early-diastolic filling in 6 to 9 months ( P <0.001 for all on longitudinal analysis). However, RV systolic function (RV S ′ z score −1.2±1.1) remained impaired 1-year post-transplant. Analysis of serial cardiac catheterization studies showed that RV and LV filling pressures were elevated early post-HT and declined gradually during the first year post-transplant.

Conclusions—

Pediatric HT recipients have biventricular dysfunction using pulsed-wave tissue Doppler imaging early after HT with most significant impairment in RV systolic function and RV and LV early-diastolic filling. Although other aspects of LV and RV function normalize in 6 to 9 months, RV systolic function remains abnormal 1 year-post-transplant.

Total donor ischemic time: relationship to early hemodynamics and intensive care morbidity in pediatric cardiac transplant recipients

OBJECTIVE

Single-center studies have failed to link modest increases in total donor ischemic time to mortality after pediatric orthotopic heart transplant. We aimed to investigate whether prolonged total donor ischemic time is linked to pediatric intensive care morbidity after orthotopic heart transplant.

DESIGN

Retrospective cohort review.

SETTING

Tertiary pediatric transplant center in the United Kingdom.

PATIENTS

Ninety-three pediatric orthotopic heart transplants between 2002 and 2006.

METHODS

Total donor ischemic time was investigated for association with early post-orthotopic heart transplant hemodynamics and intensive care unit morbidities.

RESULTS

Of 43 males and 50 females with median age 7.2 (interquartile range 2.2, 13.0) yrs, 62 (68%) had dilated cardiomyopathy, 20 (22%) had congenital heart disease, and nine (10%) had restrictive cardiomyopathy. The mean total donor ischemic time was 225.9 (sd 65.6) mins. In the first 24 hrs after orthotopic heart transplant, age-adjusted mean arterial blood pressure increased (p < .001), mean pulmonary arterial pressure fell (p = .012), but central venous pressure (p = .58) and left atrial pressure (p = .20) were unchanged. After adjustment for age, primary diagnosis, pre-orthotopic heart transplant mechanical support, and marginal donor factors, longer total donor ischemic time was significantly associated with lower mean arterial blood pressure (p < .001) in the first 24 hrs after orthotopic heart transplant, longer post-orthotopic heart transplant mechanical ventilation (p = .03), longer post-orthotopic heart transplant stay in the intensive care unit (p = .004), and longer post-orthotopic heart transplant stay in hospital (p = .02). Total donor ischemic time was not related to levels of mean pulmonary arterial pressure (p = .62), left atrial pressure (p = .38), or central venous pressure (p = .76) early after orthotopic heart transplant.

CONCLUSIONS

Prolonged total donor ischemic time has an adverse effect on the donor organ, contributing to lower mean arterial blood pressure, as well as more prolonged ventilation and intensive care unit and hospital stays post-orthotopic heart transplant, reflecting increased morbidity.