Ventricular assist device support in pediatric patients as a bridge to heart transplantation

The Journal of Heart and Lung Transplantation Volume 21, Number 1 ECMO. Patients placed on ECMO post-cardiotomy had a 31% survival. Survival was significantly improved (p⬍ .02) in patients with a diagnosis of CM (59%) versus those with CHD (25%). Patients with CM underwent 8 transplants with 7 survivors (88%), while in the CHD group, there were 8 transplants with only 2 survivors (25%), (p⬍ .05). Subanalysis of the CM group revealed that patients with acute cardiomyopathy in association with a documented viral illness had a 75% chance of being weaned off ECMO without transplant. Complications on ECMO occurred in 45% of survivors and were more frequent in nonsurvivors. Infectious complications were most frequent, followed by neurological, technical ECMO problems and renal insufficiency. In conclusion, CM has a better prognosis than CHD when using ECMO as a bridge to transplant or survival. Complications are not insignificant and increase with the duration of support. ECMO for salvage and subsequent transplant in this high-risk group of patients needs critical review. Alternative support options need to be developed in the pediatric population that will allow improved outcomes comparable to those achieved by our adult support colleagues. 205 VENTRICULAR ASSIST DEVICE SUPPORT IN PEDIATRIC PATIENTS AS A BRIDGE TO HEART TRANSPLANTATION S.K. Gandhi,1 F.A. Pigula,1 S.A. Webber,2 S. Winowich,3 R.D. Siewers,1 R.L. Kormos,3 1Division of Cardiothoracic Surgery, Children’s Hospital of Pittsburgh, Pittsburgh, PA; 2Division of Cardiology, Children’s Hospital of Pittsburgh, Pittsburgh, PA; 3 Division of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA Background: Currently available long term ventricular assist devices (VADs) are primarily utilized in adult patients. These devices are also applicable for use in intermediate-sized children and adolescents as a bridge to heart transplantation. Methods: We conducted a retrospective analysis of all pediatric patients undergoing insertion of a VAD at our institution. Results: Ten children and adolescents (7 boys, 3 girls) underwent placement of a VAD between April 1990 and August 2001. Nine patients suffered from dilated cardiomyopathy and 1 was on extracorporeal support post-cardiotomy. Six children underwent insertion of Thoratec BiVADs, 2 had insertion of Thoratec LVADs, and 2 had placement of the Novacor LVAD. Mean patient age was 14.1⫾3.2 years (range, 7 to 17 years) and mean patient weight was 75⫾22 kg (range, 52 to 113 kg). Mean implant duration was 43⫾57 days (range, 2 to 146 days). Complications of the VAD operation included bleeding requiring mediastinal reexploration in 4 patients, transient neurologic events in 2 patients, and minor infections in 3 patients. Three patients (30%) died prior to receiving a donor organ. Five patients (50%) have thus far survived to heart transplantation and 2 are still awaiting transplantation. Of the 5 patients that have been transplanted, only 1 became sensitized prior to transplant and this patient had a negative cross-match and has had a benign rejection history. Post-transplantation survival has been 100%. Conclusions: Currently available VADs are applicable for use in the intermediate-sized pediatric patient as a bridge to transplantation. Use of a VAD does not appear to significantly increase antibody sensitization pre-transplant. Although the perioperative morbidity and mortality of VAD placement is not insignificant, survival for those who receive a heart transplant is excellent.

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206 IL-10 GENE EXPRESSION AND CARDIAC ALLOGRAFT SURVIVAL WITH OR WITHOUT TREATMENT OF MONOCLONAL ANTIBODIES,CsA,DONOR-SPECIFIC TRANSFUSION AFTER RAT HEART TRANSPLANTATION Y. Huang,1 J. Xia,2 C. Yang,2 S. Ye,2 Y. Ye,1 1Nazih Zuhdi Transplant Institute, Integris Baptist Medical Center, Oklahoma City, OK; 2Department of Cardiac Surgery, The Institute of Cardiovascular Diseases of Tongji Medical College, Huazhong University of Science and Technology, Wuhan City, China Introduction: Increased tissue expression of cytokines has been observed in a number of inflammatory conditions, including allograft rejection(AR). Recently, human T cells have been categorized into Th1 and Th2 cells based upon their cytokine secretory profiles, with Th1 cells producing pro-inflammatory cytokines and Th2 cells producing cytokines which may promote graft tolerance. Interleukin 10 (IL-10) is an anti-inflammatory Th2 cytokine that modulates Th1 cytokine production. We therefore measured the expression of IL-10 gene within cardiac allografts within 14 days after rat heart transplantion and determined its relations with allograft survival with or without treatment of monoclonal antibodies(Mab),CsA,donor-specific transfusion(DSA). Methods: Rat heart transplants(SD to Wistar)were performed in five groups (group1:no treatment, group2: DSA, group3:Anti-IL2Mab, group4:Anti-IL-4mab, group5:Anti-IL-2Mab⫹CsA). Twelve objects in each group, five were used to determine allograft survival(by palpating heartbeats),seven allografts were used to detect the gene expression of IL-10(by RT-PCR)at day 1,3,5,7,9,11,14 after transplant. Allograft tissues were also submitted for histological study. Results: The allograft survival days in each group was as follows: group1 8.3⫾1.7 days, group2 29.2⫾7.1 days, group3 26.4⫾5.7 days, group4 10.2⫾1.9 days, group5 55⫾10.6 days. The express of IL-10 gene levels was upregulated and significantly higher in group 2,3,5 than in group 1,4 within 3 to 9 days after rat heart transplant. It also showed significant longer allograft survival days in groups with higher IL-10 gene expression levels than those with lower ones. Histological study showed that allografts from untreated controls and Anti-IL-4mab treated group exhibited extensive AR with loss of graft architecture by day 8 and day 10, also showed the lowest expression of IL-10 in the study, while those from other groups showed less AR. Conclusions:IL-10 plays an import role in the development of AR, suggests that Th2 type deviation may contribute to the prolongation of graft survival. 207 ACCELERATED CARDIAC ALLOGRAFT REJECTION WITH APOPTOSIS AND COMPLEMENT DEPOSITION IN Fc RECEPTOR NULL MICE B.A. Wasowska, Z. Qian, S. Rahimi, K. Fox-Talbot, W.M. Baldwin, Pathology, Johns Hopkins Medical Institutes, Baltimore, MD Alloantibody (AlloAb) is a significant component of the immune response to organ transplants. Although AlloAbs have been correlated with decreased graft survival, the mechanisms of AlloAb-mediated injury remain largely undefined in vivo. AlloAb can activate a wide variety of leukocytes, including macrophages, monocytes and NK cells through different arrays of complement and Fc receptors (CR and FcR). CR and FcR link cellular and