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Lee DH, Usmani A, Wu R, Wicks T, Noh CY, Burke R, Ravichandran V, Wolf-Doty T, Dumitru I, Oliveira GH, Berman P, Mackie B. Relationship between donor-derived cell-free DNA and tissue-based rejection-related transcripts in heart transplantation. J Heart Lung Transplant 2024; 43:1118-1125. [PMID: 38373559 DOI: 10.1016/j.healun.2024.02.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 01/30/2024] [Accepted: 02/13/2024] [Indexed: 02/21/2024] Open
Abstract
BACKGROUND Endomyocardial biopsy (EMB)-based traditional microscopy remains the gold standard for the detection of cardiac allograft rejection, despite its limitation of inherent subjectivity leading to inter-reader variability. Alternative techniques now exist to surveil for allograft injury and classify rejection. Donor-derived cell-free DNA (dd-cfDNA) testing is now a validated blood-based assay used to surveil for allograft injury. The molecular microscope diagnostic system (MMDx) utilizes intragraft rejection-associated transcripts (RATs) to classify allograft rejection and identify injury. The use of dd-cfDNA and MMDx together provides objective molecular insight into allograft injury and rejection. The aim of this study was to measure the diagnostic agreement between dd-cfDNA and MMDx and assess the relationship between dd-cfDNA and MMDx-derived RATs, which may provide further insight into the pathophysiology of allograft rejection and injury. METHODS This is a retrospective observational study of 156 EMB evaluated with traditional microscopy and MMDx. All samples were paired with dd-cfDNA from peripheral blood before EMB (up to 9 days). Diagnostic agreement between traditional histopathology, MMDx, and dd-cfDNA (threshold of 0.20%) was compared for assessment of allograft injury. In addition, the relationship between dd-cfDNA and individual RAT expression levels from MMDx was evaluated. RESULTS MMDx characterized allograft tissue as no rejection (62.8%), antibody-mediated rejection (ABMR) (26.9%), T-cell-mediated rejection (TCMR) (5.8%), and mixed ABMR/TCMR (4.5%). For the diagnosis of any type of rejection (TCMR, ABMR, and mixed rejection), there was substantial agreement between MMDx and dd-cfDNA (76.3% agreement). All transcript clusters (group of gene sets designated by MMDx) and individual transcripts considered abnormal from MMDx had significantly elevated dd-cfDNA. In addition, a positive correlation between dd-cfDNA levels and certain MMDx-derived RATs was observed. Tissue transcript clusters were correlated with dd-cfDNA scores, including DSAST, GRIT, HT1, QCMAT, and S4. For individual transcripts, tissue ROBO4 was significantly correlated with dd-cfDNA in both nonrejection and rejection as assessed by MMDx. CONCLUSIONS Collectively, we have shown substantial diagnostic agreement between dd-cfDNA and MMDx. Furthermore, based on the findings presented, we postulate a common pathway between the release of dd-cfDNA and expression of ROBO4 (a vascular endothelial-specific gene that stabilizes the vasculature) in the setting of antibody-mediated rejection, which may provide a mechanistic rationale for observed elevations in dd-cfDNA in AMR, compared to acute cellular rejection.
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Affiliation(s)
- Dae Hyun Lee
- Heart Transplant Program, Transplant Institute, Tampa General Hospital, Tampa, Florida; Division of Cardiovascular Medicine, Department of Internal Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida; Heart & Vascular Institute, Tampa General Hospital, Tampa, Florida.
| | - Ahsan Usmani
- Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Robby Wu
- Heart Transplant Program, Transplant Institute, Tampa General Hospital, Tampa, Florida; Division of Cardiovascular Medicine, Department of Internal Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida; Heart & Vascular Institute, Tampa General Hospital, Tampa, Florida
| | - Tammi Wicks
- Heart Transplant Program, Transplant Institute, Tampa General Hospital, Tampa, Florida; Heart & Vascular Institute, Tampa General Hospital, Tampa, Florida
| | - Caroline Y Noh
- Department of Pediatrics, Children's Hospital Los Angeles, USC Keck School of Medicine, Los Angeles, California
| | | | | | | | - Ioana Dumitru
- Heart Transplant Program, Transplant Institute, Tampa General Hospital, Tampa, Florida; Division of Cardiovascular Medicine, Department of Internal Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida; Heart & Vascular Institute, Tampa General Hospital, Tampa, Florida
| | - Guilherme H Oliveira
- Heart Transplant Program, Transplant Institute, Tampa General Hospital, Tampa, Florida; Division of Cardiovascular Medicine, Department of Internal Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida; Heart & Vascular Institute, Tampa General Hospital, Tampa, Florida
| | - Peter Berman
- Heart Transplant Program, Transplant Institute, Tampa General Hospital, Tampa, Florida; Division of Cardiovascular Medicine, Department of Internal Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida; Heart & Vascular Institute, Tampa General Hospital, Tampa, Florida
| | - Benjamin Mackie
- Heart Transplant Program, Transplant Institute, Tampa General Hospital, Tampa, Florida; Division of Cardiovascular Medicine, Department of Internal Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida; Heart & Vascular Institute, Tampa General Hospital, Tampa, Florida.
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Holmström EJ, Syrjälä SO, Dhaygude K, Tuuminen R, Krebs R, Lommi J, Nykänen A, Lemström KB. Donor plasma VEGF-A as a biomarker for myocardial injury and primary graft dysfunction after heart transplantation. J Heart Lung Transplant 2024:S1053-2498(24)01696-6. [PMID: 38897424 DOI: 10.1016/j.healun.2024.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 05/31/2024] [Accepted: 06/06/2024] [Indexed: 06/21/2024] Open
Abstract
BACKGROUND Vascular endothelial growth factor (VEGF)-A is an angiogenic and proinflammatory cytokine with profound effects on microvascular permeability and vasodilation. Several processes may induce VEGF-A expression in brain-dead organ donors. However, it remains unclear whether donor VEGF-A is linked to adverse outcomes after heart transplantation. METHODS We examined plasma VEGF-A levels from 83 heart transplant donors as well as the clinical data of these donors and their respective recipients operated between 2010 and 2016. The donor plasma was analyzed using Luminex-based Multiplex and confirmed with a single-target ELISA. Based on donor VEGF-A plasma levels, the recipients were divided into 3 equal-sized groups (low VEGF <500 ng/liter, n = 28; moderate VEGF 500-3000 ng/liter, n = 28; and high VEGF >3000 ng/liter, n = 27). Biochemical and clinical parameters of myocardial injury as well as heart transplant and kidney function were followed-up for one year, while rejection episodes, development of cardiac allograft vasculopathy, and mortality were monitored for 5 years. RESULTS Baseline parameters were comparable between the donor groups, except for age, where median ages of 40, 45, and 50 were observed for low, moderate, and high donor plasma VEGF levels groups, respectively, and therefore donor age was included as a confounding factor. High donor plasma VEGF-A levels were associated with pronounced myocardial injury (TnT and TnI), a higher inotrope score, and a higher incidence of primary graft dysfunction in the recipient after heart transplantation. Furthermore, recipients with allografts from donors with high plasma VEGF-A levels had a longer length of stay in the intensive care unit and the hospital, and an increased likelihood for prolonged renal replacement therapy. CONCLUSIONS Our findings suggest that elevated donor plasma VEGF-A levels were associated with adverse outcomes in heart transplant recipients, particularly in terms of myocardial injury, primary graft dysfunction, and long-term renal complications. Donor VEGF-A may serve as a potential biomarker for predicting these adverse outcomes and identifying extended donor criteria.
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Affiliation(s)
- Emil J Holmström
- Transplantation Laboratory, University of Helsinki, Helsinki, Finland; Cardiothoracic Surgery, Helsinki University Hospital, Helsinki, Finland.
| | - Simo O Syrjälä
- Transplantation Laboratory, University of Helsinki, Helsinki, Finland; Cardiothoracic Surgery, Helsinki University Hospital, Helsinki, Finland
| | - Kishor Dhaygude
- Transplantation Laboratory, University of Helsinki, Helsinki, Finland
| | - Raimo Tuuminen
- Transplantation Laboratory, University of Helsinki, Helsinki, Finland
| | - Rainer Krebs
- Transplantation Laboratory, University of Helsinki, Helsinki, Finland
| | - Jyri Lommi
- Department of Cardiology, Helsinki University Hospital, Helsinki, Finland
| | - Antti Nykänen
- Transplantation Laboratory, University of Helsinki, Helsinki, Finland; Cardiothoracic Surgery, Helsinki University Hospital, Helsinki, Finland
| | - Karl B Lemström
- Transplantation Laboratory, University of Helsinki, Helsinki, Finland; Cardiothoracic Surgery, Helsinki University Hospital, Helsinki, Finland
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Zhu Y, Dun H, Ye L, Terada Y, Shriver LP, Patti GJ, Kreisel D, Gelman AE, Wong BW. Targeting fatty acid β-oxidation impairs monocyte differentiation and prolongs heart allograft survival. JCI Insight 2022; 7:e151596. [PMID: 35239515 PMCID: PMC9057610 DOI: 10.1172/jci.insight.151596] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 03/02/2022] [Indexed: 11/17/2022] Open
Abstract
Monocytes play an important role in the regulation of alloimmune responses after heart transplantation (HTx). Recent studies have highlighted the importance of immunometabolism in the differentiation and function of myeloid cells. While the importance of glucose metabolism in monocyte differentiation and function has been reported, a role for fatty acid β-oxidation (FAO) has not been explored. Heterotopic HTx was performed using hearts from BALB/c donor mice implanted into C57BL/6 recipient mice and treated with etomoxir (eto), an irreversible inhibitor of carnitine palmitoyltransferase 1 (Cpt1), a rate-limiting step of FAO, or vehicle control. FAO inhibition prolonged HTx survival, reduced early T cell infiltration/activation, and reduced DC and macrophage infiltration to heart allografts of eto-treated recipients. ELISPOT demonstrated that splenocytes from eto-treated HTx recipients were less reactive to activated donor antigen-presenting cells. FAO inhibition reduced monocyte-to-DC and monocyte-to-macrophage differentiation in vitro and in vivo. FAO inhibition did not alter the survival of heart allografts when transplanted into Ccr2-deficient recipients, suggesting that the effects of FAO inhibition were dependent on monocyte mobilization. Finally, we confirmed the importance of FAO on monocyte differentiation in vivo using conditional deletion of Cpt1a. Our findings demonstrate that targeting FAO attenuates alloimmunity after HTx, in part through impairing monocyte differentiation.
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Affiliation(s)
| | | | | | | | | | | | - Daniel Kreisel
- Department of Surgery
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Andrew E. Gelman
- Department of Surgery
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
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Holzhauser L, Clerkin KJ, Fujino T, Alenghat FJ, Raikhelkar J, Kim G, Sayer G, Uriel N. Donor-derived cell-free DNA is associated with cardiac allograft vasculopathy. Clin Transplant 2021; 35:e14206. [PMID: 33368611 PMCID: PMC10040222 DOI: 10.1111/ctr.14206] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 11/20/2020] [Accepted: 12/07/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND The role of donor-derived cell-free DNA (dd-cfDNA) in screening for cardiac allograft vasculopathy (CAV) is unknown. We hypothesized that dd-cfDNA correlates with CAV, markers of inflammation, and angiogenesis in stable heart transplant (HT) recipients. METHODS Sixty-five HT recipients ≥2 years post-transplant, without recent rejection, were stratified by high (≥0.12%) versus low levels (<0.12%) of dd-cfDNA. A targeted amplification, next-generation sequencing assay (AlloSure® ; CareDx, Inc.) was used to detect dd-cfDNA. Peripheral blood inflammatory and angiogenesis markers were assessed using a multiplex immunoassay system (Bioplex® ). RESULTS Of 65 patients, 58 patients had a known CAV status and were included. Thirty had high levels of dd-cfDNA (≥0.12%), and 28 had low levels (<0.12%). CAV was present in 63% of patients with high dd-cfDNA vs. 35% with low dd-cfDNA (p = .047). Donor-specific antibodies were present in 25% of patients with high dd-cfDNA vs. 3.8% in those with low dd-cfDNA (p = .03). There were no differences in rejection episodes, inflammatory, or angiogenesis markers. Importantly, dd-cfDNA levels were not different when stratified by time post-transplant. CONCLUSIONS Higher dd-cfDNA levels were associated with CAV in stable chronic HT recipients. Further studies are warranted to investigate a possible association between dd-cfDNA levels and CAV severity and whether dd-cfDNA can predict CAV progression.
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Affiliation(s)
- Luise Holzhauser
- Department of Cardiology, University of Chicago, Chicago, IL, USA
| | - Kevin J Clerkin
- Department of Medicine, Milstein Division of Cardiology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Takeo Fujino
- Department of Cardiology, University of Chicago, Chicago, IL, USA
| | | | - Jayant Raikhelkar
- Department of Medicine, Milstein Division of Cardiology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Gene Kim
- Department of Cardiology, University of Chicago, Chicago, IL, USA
| | - Gabriel Sayer
- Department of Medicine, Milstein Division of Cardiology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
| | - Nir Uriel
- Department of Medicine, Milstein Division of Cardiology, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA
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CXCR4 Antagonist Reduced the Incidence of Acute Rejection and Controlled Cardiac Allograft Vasculopathy in a Swine Heart Transplant Model Receiving a Mycophenolate-based Immunosuppressive Regimen. Transplantation 2019; 102:2002-2011. [PMID: 30095739 PMCID: PMC6257103 DOI: 10.1097/tp.0000000000002404] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND CXC motif chemokine receptor 4 (CXCR4) blockade is pursued as an alternative to mesenchymal stem cell treatment in transplantation based on our previous report that burixafor, through CXCR4 antagonism, mobilizes immunomodulatory mesenchymal stem cells. Here, we explored the efficacy of combining mycophenolate mofetil (MMF)-based immunosuppressants with repetitive burixafor administration. METHODS Swine heterotopic cardiac allograft recipients received MMF and corticosteroids (control, n = 10) combined with burixafor as a 2-dose (burixafor2D, n = 7) or 2-dose plus booster injections (burixafor2D + B, n = 5) regimen. The efficacy endpoints were graft survival, freedom from first acute rejection, and the severity of intimal hyperplasia. Each specimen was sacrificed either at its first graft arrest or after 150 days. RESULTS After 150 days, all specimens in the control group had died, but 28.5% of the burixafor2D group survived, and 60% of the burixafor2D + B group survived (P = 0.0088). Although the control group demonstrated acute rejection at a median of 33.5 days, the burixafor2D + B group survived without acute rejection for a median of 136 days (P = 0.0209). Burixafor administration significantly attenuated the incidence rate of acute rejection (P = 0.002) and the severity of intimal hyperplasia (P = 0.0097) at end point relative to the controls. These findings were associated with reduced cell infiltrates in the allografts, and modulation of C-reactive protein profiles in the circulation. CONCLUSIONS The augmentation of conventional MMF plus corticosteroids with a CXCR4 antagonist is potentially effective in improving outcomes after heart transplantation in minipigs. Future studies are warranted into optimizing the therapeutic regimens for humans.
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Westhofen S, Jelinek M, Dreher L, Biermann D, Martin J, Vitzhum H, Reichenspurner H, Ehmke H, Schwoerer AP. The heterotopic heart transplantation in mice as a small animal model to study mechanical unloading - Establishment of the procedure, perioperative management and postoperative scoring. PLoS One 2019; 14:e0214513. [PMID: 30978185 PMCID: PMC6461225 DOI: 10.1371/journal.pone.0214513] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Accepted: 03/14/2019] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Unloading of failing hearts by left ventricular assist devices induces an extensive cardiac remodeling which may lead to a reversal of the initial phenotype-or to its deterioration. The mechanisms underlying these processes are unclear. HYPOTHESIS Heterotopic heart transplantion (hHTX) is an accepted model for the study of mechanical unloading in rodents. The wide variety of genetically modified strains in mice provides an unique opportunity to examine remodeling pathways. However, the procedure is technically demanding and has not been extensively used in this area. To support investigators adopting this method, we present our experience establishing the abdominal hHTX in mice and describe refinements to the technique. METHODS In this model, the transplanted heart is vascularised but implanted in series, and therefore does not contribute to systemic circulation and results in a complete mechanical unloading of the donor heart. Training followed a systematic program using a combination of literature, video tutorials, cadaveric training, direct observation and training in live animals. RESULTS Successful transplantation was defined as a recipient surviving > 24 hours with a palpable, beating apex in the transplanted heart and was achieved after 20 transplants in live animals. A success rate of 90% was reached after 60 transplants. Operative time was shown to decrease in correlation with increasing number of procedures from 200 minutes to 45 minutes after 60 operations. Cold/warm ischemia time improved from 45/100 to 10/20 minutes. Key factors for success and trouble shootings were identified. CONCLUSION Abdominal hHTX in the mouse may enable future examination of specific pathways in unloading induced myocardial remodeling. Establishment of the technique, however, is challenging. Structured training programs utilising a variety of training methods can help to expedite the process. Postoperative management, including daily scoring increases animal wellbeing and helps to predict survival.
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Affiliation(s)
- Sumi Westhofen
- Department of Cardiovascular Surgery, University Heart Center, Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
- * E-mail:
| | - Marisa Jelinek
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
- Department of Cellular and Integrative Physiology, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Leonie Dreher
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
- Department of Cellular and Integrative Physiology, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Daniel Biermann
- Department of Cardiovascular Surgery, University Heart Center, Hamburg, Germany
| | - Jack Martin
- Department of Surgery, Addenbrookes Hospital, University of Cambridge, Cambridge, United Kingdom
| | - Helga Vitzhum
- Department of Cellular and Integrative Physiology, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Hermann Reichenspurner
- Department of Cardiovascular Surgery, University Heart Center, Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Heimo Ehmke
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
- Department of Cellular and Integrative Physiology, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Alexander Peter Schwoerer
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Hamburg, Germany
- Department of Cellular and Integrative Physiology, University Medical Center Hamburg Eppendorf, Hamburg, Germany
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Watanabe K, Karimpour-Fard A, Michael A, Miyamoto SD, Nakano SJ. Elevated serum vascular endothelial growth factor and development of cardiac allograft vasculopathy in children. J Heart Lung Transplant 2018; 37:1075-1082. [PMID: 29954686 PMCID: PMC6261433 DOI: 10.1016/j.healun.2018.04.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 04/19/2018] [Accepted: 04/25/2018] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Cardiac allograft vasculopathy (CAV) is a leading cause of retransplantation and death in pediatric heart transplant recipients. Our aim was to evaluate the association between serum vascular endothelial growth factor-A (VEGF) and CAV development in the pediatric heart transplant population. METHODS In this retrospective study performed at a university hospital, VEGF concentrations were measured by enzyme-linked immunosorbent assay in banked serum from pediatric heart transplant recipients undergoing routine cardiac catheterization. In subjects with CAV (n = 29), samples were obtained at 2 time-points: before CAV diagnosis (pre-CAV) and at the time of initial CAV diagnosis (CAV). In subjects without CAV (no-CAV, n = 16), only 1 time-point was used. VEGF concentrations (n = 74) were assayed in duplicate. RESULTS Serum VEGF is elevated in pediatric heart transplant recipients before catheter-based diagnosis of CAV (no-CAV mean: 144.0 ± 89.05 pg/ml; pre-CAV mean: 316.2 ± 118.3 pg/ml; p = 0.0002). Receiver-operating characteristic curve analysis of pre-CAV VEGF levels demonstrated an area under the curve of 87.7% (p = 0.0002), with a VEGF level of 226.3 pg/ml predicting CAV development with 77.8% sensitivity and 91.7% specificity. VEGF is similarly elevated in subjects with angiographically diagnosed CAV and in those with normal angiography but intravascular ultrasound (IVUS) evidence of CAV. CONCLUSIONS The increase in serum VEGF before onset of detectable CAV is fundamental to its utility as a predictive biomarker and suggests further investigations of VEGF in the pathogenesis of CAV are warranted in the pediatric heart transplant population.
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Affiliation(s)
- Kae Watanabe
- Division of Cardiology, Department of Pediatrics, University of Colorado School of Medicine and Children's Hospital Colorado, Aurora, Colorado, USA
| | - Anis Karimpour-Fard
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Alix Michael
- Division of Cardiology, Department of Pediatrics, University of Colorado School of Medicine and Children's Hospital Colorado, Aurora, Colorado, USA
| | - Shelley D Miyamoto
- Division of Cardiology, Department of Pediatrics, University of Colorado School of Medicine and Children's Hospital Colorado, Aurora, Colorado, USA
| | - Stephanie J Nakano
- Division of Cardiology, Department of Pediatrics, University of Colorado School of Medicine and Children's Hospital Colorado, Aurora, Colorado, USA.
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