Single-center experience of pediatric heart transplantation in taiwan

Survival Outcomes of Oversized Cardiac Allografts in Pediatric Patients-A Single-Center Experience in Taiwan

OBJECTIVES

An oversized cardiac allograft may have a negative impact on survival outcomes according to previous studies; however, due to the shortage of pediatric donor hearts, the use of oversized cardiac allografts is sometimes inevitable. In this study, we reported the survival outcomes of pediatric patients in relation with the donor-recipient weight ratio.

METHODS

Twenty-eight children, aged 3 months to 17 years, with dilated cardiomyopathy underwent primary cardiac transplantation at the National Taiwan University Hospital between 1995 and 2012. We analyzed these patients according to the donor-recipient weight ratio: group 1 (n = 19) with donor-recipient weight ratio <2.5 (median 1.1, interquartile range 1.0-1.6), and group 2 (n = 9) with donor-recipient weight ratio ≥2.5 (median 3.0, inter-quartile range 2.87-3.5).

RESULTS

The 30-day survival rate was 100% for both group 1 and group 2 (P = 1). The survival rates for group 1 and group 2 were 95% vs 100% at 1 year, 84% vs 89% at 5 years, and 73% vs 61% at 10 years. The median survival was 14.4 years vs 12.9 years (P = .6313).

CONCLUSION

In this cohort, the use of oversized cardiac allograft in pediatric patients for dilated cardiomyopathy did not have a negative effect on short-term and long-term survival.

Cardiac surgical procedures for the coronary sequelae of Kawasaki disease

OBJECTIVES

The aim of this article is to make an evaluation on the clinical features of patients with Kawasaki disease who require a cardiac surgical procedure including coronary artery bypass grafting, coronary arterial aneurysmorrhaphy or heart transplantation.

METHODS

English literature of Kawasaki disease for cardiac surgery (1990-2011) was retrieved in the Pubmed database. The clinical features of the patient setting from the representative articles were collected and analyzed.

RESULTS

Patients with Kawasaki disease were very young, with some requiring a cardiac surgical procedure at a very early age. The interval between the onset and the surgical operation was 9.5±9.4 years. The prevalence of myocardial infarction and re-infarction was high. Giant aneurysm, critical stenosis with calcification and thrombus formation of the coronary arteries often warrant coronary artery bypass, heart transplantation or coronary arterial aneurysm plication. The left internal mammary artery to the left anterior descending coronary artery was the most commonly used graft in coronary artery bypass. Graft patency rate was 82.4% at 21.4±32.3 (range 0.1-252) month follow-up. The early and late mortalities of this patient setting were 0.6 and 3.0%, respectively.

CONCLUSIONS

Patients with Kawasaki disease may develop coronary artery lesions prone to aneurysmal formation with calcification and thrombus and may require coronary artery bypass at a very early age. With the left internal mammary artery as the first choice of bypass graft, the long-term patency and patient survival was satisfactory.

Endomyocardial biopsy in heart transplantation: schedule or event?

BACKGROUND

Endomyocardial biopsy is the gold standard to identify rejection after heart transplantation. Due to its invasiveness, discomfort, and difficult vascular access, some patients are not willing to accept routine scheduled biopsies years after heart transplantation. The purpose of this study was to identify whether there was a difference in outcomes among the scheduled versus event biopsy groups.

METHODS

We studied 411 patients who underwent heart transplantation from 1987 to 2011, reviewing biopsy results and pathology reports. There were 363 patients who followed the scheduled biopsy protocol, and 48 patients who were assigned to the event biopsy group. We extracted data on biopsy results, rejection episodes, rejection types, and survival time.

RESULTS

The 2481 reviewed biopsies over 24 years, showed most rejection episodes (86.4%) to occur within 2 years after heart transplantation. The rejection incidence was low (2.1%) at 3 years after transplantation. The major reason for an event biopsy was poor vascular access, such as tiny central vein or congenital disease without a suitable central vein. Event biopsy group patients were younger than schedule biopsy patients (19.7 years old vs 47.6 years old; P < .05). The 10-year survival rates were 64% among the event versus 53% among the scheduled biopsy group (P = .029). The 10-year rates of freedom from rejection were similar.

CONCLUSIONS

The rejection rate was low after 3 years; episodes occurred within 2 years. Although the long-term survival in the event group was better, they had a younger man age. The rejection and freedom from rejection rates were similar. As the rejection rate was low at 3 years after transplantation, we suggest that the event principle could be applied for biopsy at 3 years after heart transplantation.

Low donor-to-recipient weight ratio does not negatively impact survival of pediatric heart transplant patients

A major limitation to success in pediatric heart transplantation is donor organ shortage. While the use of allografts from donors larger than the recipient is accepted, the use of undersized donor grafts is generally discouraged. Using the UNOS database, we wanted to evaluate whether using smaller donor hearts affects the short- and long-term survival of pediatric heart transplant patients. A retrospective analysis of data entered into the UNOS database from April 1994 to May 2008 was performed. Pediatric heart transplant recipients (ages 0-18 yr) with DRWR <2.0 were identified and divided into two groups: Low-DRWR (<0.8) and Ideal-DRWR (0.8-2.0). Patients' demographics, pretransplant diagnoses, age at transplantation, severity of pretransplant condition, and rate of complications prior to hospital discharge after transplantation were noted. Fisher's exact, chi-square, and Wilcoxon rank sum tests were used to compare patients' baseline characteristics. Kaplan-Meier curves and Cox proportional hazard regression were used to compare patients' survival and to identify independent risk factors for outcomes. There were 3048 patients (204 with Low- and 2844 with Ideal-DRWR). The Low-ratio group patients were older (8.3 vs. 6.9 yr; p = 0.001), there was a slight male predominance in the Low-DRWR group (p = 0.055). The Low-DRWR group had longer transplant wait time than the Ideal-DRWR group (97 vs. 85 days; p = 0.04). The groups did not differ in race, primary diagnoses, severity of pretransplant condition (medical urgency status, need for ventilation, inotropic support, ECMO, nitric oxide, or dialysis, the PVR for those with bi-ventricular anatomy), or post-transplant complications (length of stay, need for inotropic support, dialysis, and rate of infections). The Low-DRWR patients had less episodes of acute rejection during the first-post-transplant month. Infants with DRWR 0.5-0.59 had lower 30-day survival rate (p = 0.045). There was no difference in short- and long-term survival between the patients with DRWR 0.6-0.79 and DRWR 0.8-2.0. Use of smaller allografts (DRWR 0.6-0.8) has no negative impact on the short- and long-term survival of pediatric heart transplant patients.