Academic Appointments


All Publications


  • Extracorporeal membrane oxygenation as a bridge to thoracic multiorgan transplantation. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation Heng, E. E., Krishnan, A., Elde, S., Garrison, A., Fawad, M., Ruaengsri, C., Shudo, Y., Guenthart, B. A., Joseph Woo, Y., MacArthur, J. W. 2024

    Abstract

    Extracorporeal membrane oxygenation (ECMO) has emerged as a crucial tool in the care of patients with multiorgan failure, and is increasingly utilized as a bridge to transplantation. While data on ECMO as a bridge to isolated heart and lung transplantation have been described, our emerging experience with ECMO as a bridge to thoracic multiorgan transplantation is not yet well understood. This study aims to investigate temporal trends, utilization, and outcomes in ECMO as a bridge to thoracic multiorgan transplantation.The United Network for Organ Sharing database was used to identify adult patients undergoing thoracic multiorgan transplantation between 1987 and 2022. Exclusion criteria were recipient age <18 and bridging with other mechanical circulatory support including ventricular assist device (VAD) and intra-aortic balloon pump (IABP). Survival analysis was performed to compare outcomes between patients bridged to transplantation with ECMO and those who were not bridged.Of 3,927 patients undergoing thoracic multiorgan transplantation, a total of 203 (5.2%) patients received ECMO as a bridge to transplantation. Among ECMO recipients, patients were most commonly bridged to heart-lung (45.8%), followed by heart-kidney (34.5%), and lung-kidney transplantation (11.8%). At a median follow-up of 35.5 months, unadjusted survival among patients bridged with ECMO was decreased versus multiorgan transplant recipients who were not bridged (p<0.001). With adjusted multivariable Cox regression, ECMO was independently associated with an elevated risk of mortality following multiorgan transplantation (HR 1.56 [1.21-2.02], p<0.01). Among patients surviving past 30 days following transplantation, conditional long-term survival was similar between those bridged with ECMO and those not bridged (p = 0.82).ECMO is increasingly utilized as a bridge to thoracic multiorgan transplantation, and is associated with increased 30 day mortality and decreased long-term survival. In select patients surviving to 30 days following transplantation, similar long-term survival is seen between patients bridged with ECMO and those not bridged.

    View details for DOI 10.1016/j.healun.2024.09.015

    View details for PubMedID 39343333

  • Heart-Liver Transplantation Utilizing the En Bloc Technique: A Single-Center Experience Over Two Decades. The Journal of thoracic and cardiovascular surgery Mullis, D. M., Garrison, A., Heng, E., Zhu, Y., Elde, S., Nilkant, R., Boyd, J., Hiesinger, W., Lee, A., Shudo, Y., Gallo, A., Bonham, C. A., Woo, Y. J., MacArthur, J. W. 2024

    Abstract

    Combined heart-liver transplantation (CHLT) is a definitive therapy reserved for patients with concomitant heart failure and advanced liver disease. A limited number of centers perform CHLT, and even fewer use the en bloc implantation technique. This study 1) reviews clinical outcomes and immunoprotective effects following CHLT, and 2) describes our institution's experience of over two decades using the en bloc technique.All patients who underwent CHLT at our institution between January 2003 and July 2023 were identified. Recipient and donor characteristics, operative details, and clinical outcomes were assessed. Kaplan-Meier analysis was performed to evaluate survival following CHLT.A total of 20 patients underwent CHLT using the en bloc technique at our institution between January 2003 and July 2023. At a median follow-up of 3.8 years for patients who survived the perioperative period (n=18), estimated survival at 1- and 5-years was 94% and 75%, respectively. There was 100% freedom from acute moderate rejection, acute severe rejection, and chronic rejection in all patients. No patients required re-transplantation due to rejection.CHLT is a definitive therapy reserved for patients with multi-organ dysfunction. At our institution, the en bloc technique is the preferred operative approach, as it minimizes cardiac insult, requires fewer anastomoses, minimizes cold ischemia time, and allows for rapid correction of coagulopathy. Overall survival for this cohort is excellent. Episodes of acute rejection were rarely observed, providing further support that the liver may serve an immunoprotective role in multi-organ transplantation.

    View details for DOI 10.1016/j.jtcvs.2024.08.031

    View details for PubMedID 39187122

  • Survival, Function, and Immune Profiling after Beating Heart Transplantation. The Journal of thoracic and cardiovascular surgery Krishnan, A., Elde, S., Ruaengsri, C., Guenthart, B. A., Zhu, Y., Fawad, M., Lee, A., Currie, M., Ma, M. R., Hiesinger, W., Shudo, Y., MacArthur, J. W., Woo, Y. J. 2024

    Abstract

    Ex-vivo normothermic perfusion of cardiac allografts has expanded the donor pool. Utilizing a beating heart implantation method avoids the second cardioplegic arrest and subsequent ischemia reperfusion injury typically associated with ex-vivo heart perfusion. We sought to describe our institutional experience with beating heart transplantation.This was a single-institution retrospective study of adult patients who underwent heart transplantation utilizing ex-vivo heart perfusion (EVHP) and a beating heart implantation technique between October 2022 and March 2024. Primary outcomes of interest included survival, initiation of mechanical circulatory support, and rejection. A sub-analysis of our institutional series of non-beating DCD heart transplantation was also performed.Twenty-four patients underwent isolated heart transplantation with the use of ex-vivo heart perfusion and beating heart implantation between October 2022 and March 2024; 21 (87.5%) received hearts from DCD donors, and 3 (12.5%) patients received hearts from DBD donors. Median follow-up was 192 days (interquartile range of 124-253.5 days), and 23 out of 24 patients (95.8%) were alive at last follow up. No patients required initiation of mechanical circulatory support. The majority of patients had pathological grade 0 rejection at the time of biopsy (n=16, 66.7%), and the median cell-free DNA percent was 0.04% (interquartile range 0.04-0.09). The rate of mechanical circulatory support initiation in the 22-patient non-beating DCD heart transplant cohort was significantly higher at 36.4% (p<0.005).A beating heart implantation technique can be used on DCD and DBD hearts on EVHP and is associated with excellent survival and low levels of rejection.

    View details for DOI 10.1016/j.jtcvs.2024.07.058

    View details for PubMedID 39111693

  • Repair of giant pulmonary artery aneurysm by reimplantation valve-sparing pulmonic root replacement. JTCVS techniques Wang, H., Elde, S., Zhu, Y., Woo, Y. J. 2024; 26: 40-42

    View details for DOI 10.1016/j.xjtc.2024.05.020

    View details for PubMedID 39156521

    View details for PubMedCentralID PMC11329204

  • Discussion to: Four decades of progress in heart-lung transplantation: Two hundred seventy-one cases at a single institution JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY Elde, S., Huddleston, C., Woo, Y. 2024; 168 (2): 593-594

    View details for DOI 10.1016/j.jtcvs.2024.02.016

    View details for Web of Science ID 001272206700001

    View details for PubMedID 38530679

  • Repair of giant pulmonary artery aneurysm by reimplantation valve-sparing pulmonic root replacement JTCVS TECHNIQUES Wang, H., Elde, S., Zhu, Y., Woo, Y. 2024; 26: 40-42
  • Structural, angiogenic, and immune responses influencing myocardial regeneration: a glimpse into the crucible. NPJ Regenerative medicine Baccouche, B. M., Elde, S., Wang, H., Woo, Y. J. 2024; 9 (1): 18

    Abstract

    Complete cardiac regeneration remains an elusive therapeutic goal. Although much attention has been focused on cardiomyocyte proliferation, especially in neonatal mammals, recent investigations have unearthed mechanisms by which non-cardiomyocytes, such as endothelial cells, fibroblasts, macrophages, and other immune cells, play critical roles in modulating the regenerative capacity of the injured heart. The degree to which each of these cell types influence cardiac regeneration, however, remains incompletely understood. This review highlights the roles of these non-cardiomyocytes and their respective contributions to cardiac regeneration, with emphasis on natural heart regeneration after cardiac injury during the neonatal period.

    View details for DOI 10.1038/s41536-024-00357-z

    View details for PubMedID 38688935

    View details for PubMedCentralID 4243683

  • Large Animal Translational Validation of 3 Mitral Valve Repair Operations for Mitral Regurgitation Using a Mitral Valve Prolapse Model: A Comprehensive In Vivo Biomechanical Engineering Analysis. Circulation. Cardiovascular interventions Zhu, Y., Yajima, S., Park, M. H., Venkatesh, A., Stark, C. J., Tran, N. A., Walsh, S. K., Ethiraj, S., Wilkerson, R. J., Lin, L. E., Lee, S. H., Gates, K. Y., Arthur, J. D., Baker, S. W., Mullis, D. M., Wu, C. A., Harima, S., Pokhrel, B., Resuello, D., Bergamasco, H., Wu, M. A., Baccouche, B. M., Pandya, P. K., Elde, S., Wang, H., Woo, Y. J. 2024; 17 (4): e013196

    Abstract

    Various mitral repair techniques have been described. Though these repair techniques can be highly effective when performed correctly in suitable patients, limited quantitative biomechanical data are available. Validation and thorough biomechanical evaluation of these repair techniques from translational large animal in vivo studies in a standardized, translatable fashion are lacking. We sought to evaluate and validate biomechanical differences among different mitral repair techniques and further optimize repair operations using a large animal mitral valve prolapse model.Male Dorset sheep (n=20) had P2 chordae severed to create the mitral valve prolapse model. Fiber Bragg grating force sensors were implanted to measure chordal forces. Ten sheep underwent 3 randomized, paired mitral valve repair operations: neochord repair, nonresectional leaflet remodeling, and triangular resection. The other 10 sheep underwent neochord repair with 2, 4, and 6 neochordae. Data were collected at baseline, mitral valve prolapse, and after each repair.All mitral repair techniques successfully eliminated regurgitation. Compared with mitral valve prolapse (0.54±0.18 N), repair using neochord (0.37±0.20 N; P=0.02) and remodeling techniques (0.30±0.15 N; P=0.001) reduced secondary chordae peak force. Neochord repair further decreased primary chordae peak force (0.21±0.14 N) to baseline levels (0.20±0.17 N; P=0.83), and was associated with lower primary chordae peak force compared with the remodeling (0.34±0.18 N; P=0.02) and triangular resectional techniques (0.36±0.27 N; P=0.03). Specifically, repair using 2 neochordae resulted in higher peak primary chordal forces (0.28±0.21 N) compared with those using 4 (0.22±0.16 N; P=0.02) or 6 neochordae (0.19±0.16 N; P=0.002). No difference in peak primary chordal forces was observed between 4 and 6 neochordae (P=0.05). Peak forces on the neochordae were the lowest using 6 neochordae (0.09±0.11 N) compared with those of 4 neochordae (0.15±0.14 N; P=0.01) and 2 neochordae (0.29±0.18 N; P=0.001).Significant biomechanical differences were observed underlying different mitral repair techniques in a translational large animal model. Neochord repair was associated with the lowest primary chordae peak force compared to the remodeling and triangular resectional techniques. Additionally, neochord repair using at least 4 neochordae was associated with lower chordal forces on the primary chordae and the neochordae. This study provided key insights about mitral valve repair optimization and may further improve repair durability.

    View details for DOI 10.1161/CIRCINTERVENTIONS.123.013196

    View details for PubMedID 38626077

  • Stromal cell-derived factor-1 alpha improves cardiac function in a novel diet-induced coronary atherosclerosis model, the SR-B1ΔCT/LDLR KO mouse. Atherosclerosis Mullis, D. M., Padilla-Lopez, A., Wang, H., Zhu, Y., Elde, S., Bonham, S. A., Yajima, S., Kocher, O. N., Krieger, M., Woo, Y. J. 2024: 117518

    Abstract

    There are a limited number of pharmacologic therapies for coronary artery disease, and few rodent models of occlusive coronary atherosclerosis and consequent myocardial infarction with which one can rapidly test new therapeutic approaches. Here, we characterize a novel, fertile, and easy-to-use HDL receptor (SR-B1)-based model of atherogenic diet-inducible, fatal coronary atherosclerosis, the SR-B1ΔCT/LDLR KO mouse. Additionally, we test intramyocardial injection of Stromal Cell-Derived Factor-1 alpha (SDF-1α), a potent angiogenic cytokine, as a possible therapy to rescue cardiac function in this mouse.SR-B1ΔCT/LDLR KO mice were fed the Paigen diet or standard chow diet, and we determined the effects of the diets on cardiac function, histology, and survival. After two weeks of feeding either the Paigen diet (n = 24) or standard chow diet (n = 20), the mice received an intramyocardial injection of either SDF-1α or phosphate buffered saline (PBS). Cardiac function and angiogenesis were assessed two weeks later.When six-week-old mice were fed the Paigen diet, they began to die as early as 19 days later and 50% had died by 38 days. None of the mice maintained on the standard chow diet died by day 72. Hearts from mice on the Paigen diet showed evidence of cardiomegaly, myocardial infarction, and occlusive coronary artery disease. For the five mice that survived until day 28 that underwent an intramyocardial injection of PBS on day 15, the average ejection fraction (EF) decreased significantly from day 14 (the day before injection, 52.1 ± 4.3%) to day 28 (13 days after the injection, 30.6 ± 6.8%) (paired t-test, n = 5, p = 0.0008). Of the 11 mice fed the Paigen diet and injected with SDF-1α on day 15, 8 (72.7%) survived to day 28. The average EF for these 8 mice increased significantly from 48.2 ± 7.2% on day 14 to63.6 ± 6.9% on day 28 (Paired t-test, n = 8, p = 0.003).This new mouse model and treatment with the promising angiogenic cytokine SDF-1α may lead to new therapeutic approaches for ischemic heart disease.

    View details for DOI 10.1016/j.atherosclerosis.2024.117518

    View details for PubMedID 38627162

  • Four Decades of Progress in Heart-Lung Transplantation: 271 Cases at a Single Institution. The Journal of thoracic and cardiovascular surgery Elde, S., Baccouche, B. M., Mullis, D. M., Leipzig, M. M., Deuse, T., Krishnan, A., Fawad, M., Dale, R., Walsh, S., Padilla-Lopez, A., Wesley, B., He, H., Yajima, S., Zhu, Y., Wang, H., Guenthart, B. A., Shudo, Y., Reitz, B. A., Woo, Y. J. 2024

    Abstract

    OBJECTIVE: The objective of this study is to evaluate survival for combined heart-lung transplant (HLTx) recipients across four decades at a single institution. We aim to summarize our contemporary practice based upon more than 271 HLTx over 40 years.METHODS: Data were collected from a departmental database and the United Network for Organ Sharing (UNOS). Recipients <18y, those undergoing redo HLTx , or triple-organ system transplantation were excluded, leaving 271 patients for analysis. The Pioneering Era was defined by date of transplant between 1981-2000 (N=155), and the Modern Era between 2001-2022 (N=116). Survival analysis was performed using cardinality matching of populations based on donor and recipient age, donor and recipient sex, ischemic time, and sex-matching.RESULTS: Between 1981-2022, 271 HLTx were performed at a single institution. Recipients in the Modern Era were older (42 vs 34y, P<0.001) and had shorter waitlist times (78 vs 234d, P<0.001). Allografts from female donors were more common in the Modern Era (59% vs 39%, P=0.002). In the matched survival analysis, 30-day survival (97% vs 84%, P=0.005), 1-year survival (89% vs 77%, P=0.041), and 10-year survival (53% vs 26%, P=0.012) significantly improved in the Modern Era relative to the Pioneering Era, respectively.CONCLUSIONS: Long-term survival in HLTx is achievable with institutional experience and may continue to improve in the coming decades. Advances in mechanical circulatory support, improved maintenance immunosuppression, and early recognition and management of acute complications such as primary graft dysfunction and acute rejection have dramatically improved the prognosis for HLTx recipients in our contemporary institutional experience.

    View details for DOI 10.1016/j.jtcvs.2024.01.042

    View details for PubMedID 38320627

  • Beating Heart Transplantation: How to Do It. Innovations (Philadelphia, Pa.) Krishnan, A., Guenthart, B. A., Ruengesri, C., Elde, S., Zhu, Y., MacArthur, J. W., Woo, Y. J. 2024: 15569845231220678

    Abstract

    Heart transplantation utilizing deceased after circulatory death (DCD) donors has expanded the donor pool through the use of ex vivo normothermic perfusion. Compared with brain death donation, the conventional method of performing DCD heart transplantation includes an additional period of warm and cold ischemia. We have developed a beating heart implantation technique that obliviates the need for a second cardioplegic arrest and the associated reperfusion injury. We hypothesize this reproducible method may improve short-term and long-term outcomes to mirror results seen in brain death donors and provide details on how to perform beating heart transplantation.

    View details for DOI 10.1177/15569845231220678

    View details for PubMedID 38258625

  • Neochords: How long, how many, too many? JTCVS techniques Elde, S., Woo, Y. J. 2023; 22: 59-64

    View details for DOI 10.1016/j.xjtc.2023.10.018

    View details for PubMedID 38152190

    View details for PubMedCentralID PMC10750996

  • Biomechanics and clinical outcomes of various conduit configurations in valve sparing aortic root replacement. Annals of cardiothoracic surgery Zhu, Y., Park, M. H., Pandya, P. K., Stark, C. J., Mullis, D. M., Walsh, S. K., Kim, J. Y., Wu, C. A., Baccouche, B. M., Lee, S. H., Baraka, A. S., Joo, H., Yajima, S., Elde, S., Woo, Y. J. 2023; 12 (4): 326-337

    Abstract

    Several conduit configurations, such as straight graft (SG), Valsalva graft (VG), anticommissural plication (ACP), and the Stanford modification (SMOD) technique, have been described for the valve-sparing aortic root replacement (VSARR) procedure. Prior ex vivo studies have evaluated the impact of conduit configurations on root biomechanics, but the mock coronary artery circuits used could not replicate the physical properties of native coronary arteries. Moreover, the individual leaflet's biomechanics, including the fluttering phenomenon, were unclear.Porcine aortic roots with coronary arteries were explanted (n=5) and underwent VSARR using SG, VG, ACP, and SMOD for evaluation in an ex vivo left heart flow loop simulator. Additionally, 762 patients who underwent VSARR from 1993 through 2022 at our center were retrospectively reviewed. Analysis of variance was performed to evaluate differences between different conduit configurations, with post hoc Tukey's correction for pairwise testing.SG demonstrated lower rapid leaflet opening velocity compared with VG (P=0.001) and SMOD (P=0.045) in the left coronary cusp (LCC), lower rapid leaflet closing velocity compared with VG (P=0.04) in the right coronary cusp (RCC), and lower relative opening force compared with ACP (P=0.04) in the RCC. The flutter frequency was lower in baseline compared with VG (P=0.02) and in VG compared with ACP (P=0.03) in the LCC. Left coronary artery mean flow was higher in SG compared with SMOD (P=0.02) and ACP (P=0.05). Clinically, operations using SG compared with sinus-containing graft was associated with shorter aortic cross-clamp and cardiopulmonary bypass time (P<0.001, <0.001).SG demonstrated hemodynamics and biomechanics most closely recapitulating those from the native root with significantly shorter intraoperative times compared with repair using sinus-containing graft. Future in vivo validation studies as well as correlation with comprehensive, comparative clinical study outcomes may provide additional invaluable insights regarding strategies to further enhance repair durability.

    View details for DOI 10.21037/acs-2023-avs2-0068

    View details for PubMedID 37554719

    View details for PubMedCentralID PMC10405339

  • Trimmed central venous catheters do not increase endothelial injury in an ovine model. The journal of vascular access Wang, H., Williams, K. M., Elde, S., Bulterys, P. L., Thakore, A. D., Lucian, H. J., Farry, J. M., Mullis, D. M., Zhu, Y., Paulsen, M. J., Woo, Y. J. 2023: 11297298231153716

    Abstract

    Central venous catheters (CVCs) are often trimmed during heart transplantation and pediatric cardiac surgery. However, the risk of endothelial injury caused by the cut tip of the CVC has not been evaluated. We hypothesized that there is no difference in the degree of endothelial injury associated with trimmed CVCs versus standard untrimmed CVCs.In four adult male sheep, the left external jugular vein was exposed in three segments, one designated for an untouched control group, one for the trimmed CVC group, and one for the untrimmed CVC group. Trimmed and untrimmed CVC tips were rotated circumferentially within their respective segments to abrade the lumen of the vein. The vein samples were explanted, and two representative sections from each sample were analyzed using hematoxylin and eosin (H&E) staining, as well as with immunohistochemistry against CD31, von Willebrand factor (vWF), endothelial nitric oxide synthase (eNOS), and caveolin. Higher immunohistochemical stain distributions and intensities are associated with normal health and function of the venous endothelium. Data are presented as counts with percentages or as means with standard error.H&E staining revealed no evidence of endothelial injury in 6/8 (75%) samples from the untouched control group, and no injury in 4/8 (50%) samples from both the trimmed and untrimmed CVC groups (p = 0.504). In all remaining samples from each group, only mild endothelial injury was observed. Immunohistochemical analysis comparing trimmed CVCs versus untrimmed CVCs revealed no difference in the percentage of endothelial cells staining positive for CD31 (57.5% ± 7.2% vs 55.0% ± 9.2%, p = 0.982), vWF (73.8% ± 8.0% vs 62.5% ± 9.6%, p = 0.579), eNOS (66.3% ± 4.2% vs 63.8% ± 7.5%, p = 0.962), and caveolin (53.8% ± 5.0% vs 51.3% ± 4.4%, p = 0.922). There were no significant differences between the groups in the distributions of stain intensity for CD31, vWF, eNOS, and caveolin.Trimmed CVCs do not increase endothelial injury compared to standard untrimmed CVCs.

    View details for DOI 10.1177/11297298231153716

    View details for PubMedID 36765464

  • Revised Heart Allocation Policy Improved Waitlist Mortality and Waiting Time With Maintained Outcomes in En-Bloc Heart-Lung Transplant Candidates and Recipients. Transplant international : official journal of the European Society for Organ Transplantation Shudo, Y., He, H., Elde, S., Woo, Y. J. 2023; 36: 11956

    Abstract

    The revised United Network for Organ Sharing heart allocation policy was implemented in October 2018. Using a national transplant database, this study evaluated the transplant rate, waitlist mortality, waiting time, and other outcomes of en-bloc heart-lung transplantation recipients. Adult patients registered on the national database for heart-lung transplants before and after the policy update were selected as cohorts. Baseline characteristics, transplant rates, waitlist mortality, waiting times, and other outcomes were compared between the two periods. In total, 370 patients were registered for heart-lung transplants during the pre- and post-periods. There were significantly higher transplant rates, shorter waitlist times, and substantially reduced waitlist mortality in the post-period. Registered patients waitlisted in the post-period had significantly higher utilization of intra-aortic balloon pumps, extracorporeal membrane oxygenation, and overall life support, including ventricular assist devices. Transplant recipients had significantly longer ischemic times, increased transport distances, and shorter waiting times before transplantation in the post-policy period. Transplant recipients held similar short-term survival before and after the policy change (log-rank test, p = 0.4357). Therefore, the revised policy significantly improved access to en-bloc heart-lung allografts compared with the prior policy, with better waitlist outcomes and similar post-transplant outcomes.

    View details for DOI 10.3389/ti.2023.11956

    View details for PubMedID 38152546

  • Surgical management of severe mitral annular calcification. Asian cardiovascular & thoracic annals Elde, S., Zhu, Y., MacArthur, J. W., Woo, Y. J. 2022: 2184923221136935

    Abstract

    BACKGROUND: Surgical management of severe mitral annular calcification (MAC) presents a challenging problem for even the most experienced surgeons. Preoperative planning is the most effective strategy to mitigate risk in these scenarios. MAC alone should not disqualify a patient from consideration for mitral valve repair, although the presence of concurrent greater than moderate stenosis warrants consideration of mitral valve replacement.METHODS: While repair and replacement techniques for mitral regurgitation in the setting of MAC overlap with those used to repair a non-calcified mitral apparatus, there are unique considerations to the surgical conduct of these procedures. Specifically, this article describes techniques that may be employed when the severity of MAC precludes typical repair or replacement strategies.RESULTS: Between 2014 and 2021, 77 patients were operated on by a single surgeon for mitral valve disease complicated by severe MAC. Using the systematic approach described herein, 1-year mortality was 7.8% and overall mortality over a follow-up period extending 1 to 8 years was 9.1%.CONCLUSIONS: Despite the inherent challenges of mitral valve repair or replacement in the setting of severe MAC, a systematic approach beginning with preoperative planning, modification of annular suture placement, and techniques to mitigate severe complications have, in our experience, resulting in a reliable methodology for managing severe MAC with excellent outcomes.

    View details for DOI 10.1177/02184923221136935

    View details for PubMedID 36537728

  • Outcomes of Heart Transplantation Using a Temperature-controlled Hypothermic Storage System. Transplantation Zhu, Y., Shudo, Y., He, H., Kim, J. Y., Elde, S., Williams, K. M., Walsh, S. K., Koyano, T. K., Guenthart, B., Woo, Y. J. 2022

    Abstract

    The SherpaPak Cardiac Transport System is a novel technology that provides stable, optimal hypothermic control during organ transport. The objectives of this study were to describe our experience using the SherpaPak system and to compare outcomes after heart transplantation after using SherpaPak versus the conventional static cold storage method (non-SherpaPak).From 2018 to June 2021, 62 SherpaPak and 186 non-SherpaPak patients underwent primary heart transplantation at Stanford University with follow-up through May 2022. The primary end point was all-cause mortality, and secondary end points were postoperative complications. Optimal variable ratio matching, cox proportional hazards regression model, and Kaplan-Meier survival analyses were performed.Before matching, the SherpaPak versus non-SherpaPak patients were older and received organs with significantly longer total allograft ischemic time. After matching, SherpaPak patients required fewer units of blood product for perioperative transfusion compared with non-SherpaPak patients but otherwise had similar postoperative outcomes such as hospital length of stay, primary graft dysfunction, inotrope score, mechanical circulatory support use, cerebral vascular accident, myocardial infarction, respiratory failure, new renal failure requiring dialysis, postoperative bleeding or tamponade requiring reoperation, infection, and survival.In conclusion, this is one of the first retrospective comparison studies that evaluated the outcomes of heart transplantation using organs preserved and transported via the SherpaPak system. Given the excellent outcomes, despite prolonged total allograft ischemic time, it may be reasonable to adopt the SherpaPak system to accept organs from a remote location to further expand the donor pool.

    View details for DOI 10.1097/TP.0000000000004416

    View details for PubMedID 36510359

  • Type A Aortic Dissection With Concurrent Aortic Valve Endocarditis, Subarachnoid Hemorrhage, and Disseminated Intravascular Coagulation. JACC. Case reports Elde, S. F., Guenthart, B. A., de Biasi, A., Dalal, A. R., Casselman, K. G., Hiesinger, W., Burton, E. C. 2022; 4 (14): 839-843

    Abstract

    We describe surgical repair of a Stanford Type A aortic dissection with concurrent aortic valve Streptococcus equi endocarditis in the setting of subarachnoid hemorrhage and disseminated intravascular coagulation. Multidisciplinary collaboration among specialists from a variety of disciplines is essential when treating acutely ill cardiovascular patients with multisystem involvement. (Level of Difficulty: Beginner.).

    View details for DOI 10.1016/j.jaccas.2021.05.008

    View details for PubMedID 35912321

  • An automated line-clearing chest tube system after cardiac surgery. JTCVS open Obafemi, O. O., Wang, H., Bajaj, S. S., O'Donnell, C. T., Elde, S., Boyd, J. H. 2022; 10: 246-253

    Abstract

    To complete the first in-human study of the automated line clearance Thoraguard chest tube system. The study focuses on the viability and efficacy of the device in comparison with conventional models as well as secondary matters such as patient experience and ease of use.This was a single-center, prospective, open-label study involving adult patients (n = 27) who underwent nonemergent, first-time, cardiac surgery. Patients received automated clearance chest tubes for surgical drainage in both the mediastinal and pleural spaces. The control group was retrospective (n = 80); individuals received conventional chest tubes placed and secured in locations determined at the surgeon's discretion.The automated-clearance tubes exhibited a similar drainage profile at 1, 3, 6, 12, and 24 hours compared with the conventional chest tubes. The final output at the time of tube removal was also similar (1150 [750-1590] vs 1289 [766.3-1890] mL, respectively, P = .76). The number of patients readmitted for drainage of an effusion was similar in both groups (1/27 [3.7%] vs 3/80 [3.75%], P > .99).This study has shown that the Centese Thoraguard chest tube system is a viable option for surgical chest drainage and effective when used in routine cardiac surgery operations.

    View details for DOI 10.1016/j.xjon.2022.02.020

    View details for PubMedID 36004272

    View details for PubMedCentralID PMC9390781

  • Exvivo aortic valve replacement before orthotopic heart transplantation. JTCVS techniques Elde, S. F., Guenthart, B. A., Shudo, Y., Woo, Y. J. 2022; 12: 118-120

    View details for DOI 10.1016/j.xjtc.2022.01.008

    View details for PubMedID 35403016

  • Electrophysiologic Conservation of Epicardial Conduction Dynamics After Myocardial Infarction and Natural Heart Regeneration in Newborn Piglets. Frontiers in cardiovascular medicine Wang, H., Pong, T., Obafemi, O. O., Lucian, H. J., Aparicio-Valenzuela, J., Tran, N. A., Mullis, D. M., Elde, S., Tada, Y., Baker, S. W., Wang, C. Y., Cyr, K. J., Paulsen, M. J., Zhu, Y., Lee, A. M., Woo, Y. J. 2022; 9: 829546

    Abstract

    Newborn mammals, including piglets, exhibit natural heart regeneration after myocardial infarction (MI) on postnatal day 1 (P1), but this ability is lost by postnatal day 7 (P7). The electrophysiologic properties of this naturally regenerated myocardium have not been examined. We hypothesized that epicardial conduction is preserved after P1 MI in piglets. Yorkshire-Landrace piglets underwent left anterior descending coronary artery ligation at age P1 (n = 6) or P7 (n = 7), After 7 weeks, cardiac magnetic resonance imaging was performed with late gadolinium enhancement for analysis of fibrosis. Epicardial conduction mapping was performed using custom 3D-printed high-resolution mapping arrays. Age- and weight-matched healthy pigs served as controls (n = 6). At the study endpoint, left ventricular (LV) ejection fraction was similar for controls and P1 pigs (46.4 ± 3.0% vs. 40.3 ± 4.9%, p = 0.132), but significantly depressed for P7 pigs (30.2 ± 6.6%, p < 0.001 vs. control). The percentage of LV myocardial volume consisting of fibrotic scar was 1.0 ± 0.4% in controls, 9.9 ± 4.4% in P1 pigs (p = 0.002 vs. control), and 17.3 ± 4.6% in P7 pigs (p < 0.001 vs. control, p = 0.007 vs. P1). Isochrone activation maps and apex activation time were similar between controls and P1 pigs (9.4 ± 1.6 vs. 7.8 ± 0.9 ms, p = 0.649), but significantly prolonged in P7 pigs (21.3 ± 5.1 ms, p < 0.001 vs. control, p < 0.001 vs. P1). Conduction velocity was similar between controls and P1 pigs (1.0 ± 0.2 vs. 1.1 ± 0.4 mm/ms, p = 0.852), but slower in P7 pigs (0.7 ± 0.2 mm/ms, p = 0.129 vs. control, p = 0.052 vs. P1). Overall, our data suggest that epicardial conduction dynamics are conserved in the setting of natural heart regeneration in piglets after P1 MI.

    View details for DOI 10.3389/fcvm.2022.829546

    View details for PubMedID 35355973

  • Analysis of the revised heart allocation policy and the influence of increased mechanical circulatory support on survival. The Journal of thoracic and cardiovascular surgery Elde, S., He, H., Lingala, B., Baiocchi, M., Wang, H., Hiesinger, W., MacArthur, J. W., Shudo, Y., Woo, Y. J. 1800

    Abstract

    OBJECTIVES: In 2018, the new United Network for Organ Sharing heart allocation policy took effect. This study evaluated waitlist mortality, mechanical circulatory support utilization, and its influence on posttransplant survival.METHODS: Two 12-month cohorts matched for time of year before and after the policy change were defined by inclusion criteria of first-time transplant recipients aged 18years or older who were listed and underwent transplant during the same era. Student t test and Wilcoxon rank-sum test were used for mean and median differences, respectively. Categorical variables were compared using chi2 or Fisher exact test. Kaplan-Meier curves were used to characterize survival, including time-to-event analysis with the log-rank test. Fine-Gray modeling was used to characterize waitlist mortality. Cox proportional-hazard models were used for multivariate analysis.RESULTS: Waitlist mortality in the new era is significantly improved based on a competing-risks model (Gray test P=.0064). Unadjusted 180-day posttransplant mortality increased from 5.8% during the old era to 8.0% during the new (P=.0134). However, time-to-event analysis showed similar 180-day survival in both eras. After risk adjustment, the hazard ratio for posttransplant 180-day mortality during the new era was 1.18 (95% CI, 0.85-1.64; P=.333). The posttransplant 180-day mortality of the extracorporeal membrane oxygenation bridge-to-transplant subgroup improved from 28.6% in the old era to 8.4% in the new era (P=.0103; log-rank P=.0021). Patients with an intra-aortic balloon pump at the time of transplant had similar 180-day posttransplant mortality between eras (5.4% vs 7.0%; P=.4831).CONCLUSIONS: The United Network for Organ Sharing policy change is associated with reduced waitlist mortality and similar risk adjusted posttransplant 180-day mortality. The new era is also associated with improved 180-day survival in patientsundergoing bridge to transplant with extracorporeal membrane oxygenation.

    View details for DOI 10.1016/j.jtcvs.2021.11.076

    View details for PubMedID 35027214

  • Extracorporeal Membrane Oxygenation Bridge to Heart-Lung Transplantation. ASAIO journal (American Society for Artificial Internal Organs : 1992) Shudo, Y., Elde, S., Lingala, B., He, H., Casselman, K. G., Zhu, Y., Kasinpila, P., Woo, Y. J. 2021

    View details for DOI 10.1097/MAT.0000000000001457

    View details for PubMedID 34843181

  • Operative Technique of Donor Organ Procurement for En Bloc Heart-Liver Transplantation. Transplantation Elde, S. n., Brubaker, A. L., Than, P. A., Rinewalt, D. n., MacArthur, J. W., Alassar, A. n., Bonham, C. A., Esquivel, C. O., Shudo, Y. n., Concepcion, W. n., Woo, Y. J. 2021

    Abstract

    Combined heart-liver transplant is an emerging option for patients with indications for heart transplantation and otherwise prohibitive hepatic dysfunction. Heart-liver transplantation is particularly relevant for patients with single ventricle physiology who often develop Fontan-associated liver disease and fibrosis. While only performed at a limited number of centers, several approaches to combined heart-liver transplantation have been described. The en bloc technique offers several potential advantages over the traditional sequential technique. Specifically, en bloc heart-liver transplantation may allow improved hemodynamics, decreased bleeding, reduced liver allograft ischemic time, and may result in reduced rates of graft dysfunction. Here we describe our center's en bloc heart-liver procurement technique in detail, with the aim of allowing broader use and standardization of this technique. Supplemental Visual Abstract; http://links.lww.com/TP/C147.

    View details for DOI 10.1097/TP.0000000000003697

    View details for PubMedID 33606485

  • The Expanding Armamentarium of Innovative Bioengineered Strategies to Augment Cardiovascular Repair and Regeneration Frontiers in Bioengineering and Biotechnology Elde, S., Wang, H., Woo, Y. 2021: 674172

    Abstract

    Cardiovascular disease remains the leading cause of death worldwide. While clinical trials of cell therapy have demonstrated largely neutral results, recent investigations into the mechanisms of natural myocardial regeneration have demonstrated promising new intersections between molecular, cellular, tissue, biomaterial, and biomechanical engineering solutions. New insight into the crucial role of inflammation in natural regenerative processes may explain why previous efforts have yielded only modest degrees of regeneration. Furthermore, the new understanding of the interdependent relationship of inflammation and myocardial regeneration have catalyzed the emergence of promising new areas of investigation at the intersection of many fields.

    View details for DOI 10.3389/fbioe.2021.674172

    View details for PubMedCentralID PMC8205517

  • Navigating the Crossroads of Cell Therapy and Natural Heart Regeneration Frontiers in Cell and Developmental Biology Elde, S., Wang, H., Woo, Y. 2021: 674180

    Abstract

    Cardiovascular disease remains the leading cause of death worldwide despite significant advances in our understanding of the disease and its treatment. Consequently, the therapeutic potential of cell therapy and induction of natural myocardial regeneration have stimulated a recent surge of research and clinical trials aimed at addressing this challenge. Recent developments in the field have shed new light on the intricate relationship between inflammation and natural regeneration, an intersection that warrants further investigation.

    View details for DOI 10.3389/fcell.2021.674180

    View details for PubMedCentralID PMC8148343

  • Extracorporeal Membrane Oxygenation Bridge to Heart-Lung Transplantation ASAIO Shudo, Y., Elde, S., Lingala, B., He, H., Casselman, K. G., Zhu, Y., Kasinpila, P., Woo, Y. 2021
  • A Novel Alternative to The Commando Procedure: Constructing a Neo-Aortic Root by Anchoring to the Sewing Ring of the Replaced Mitral Valve. JTCVS techniques Elde, S., de Biasi, A., Woo, Y. J., Burton, E. 2020

    View details for DOI 10.1016/j.xjtc.2020.08.037

    View details for PubMedID 32875308

  • The Thoracic Surgery Social Media Network Experience During the COVID-19 Pandemic. The Annals of thoracic surgery Luc, J. G., Archer, M. A., Arora, R. C., Bender, E. M., Blitz, A., Cooke, D. T., Elde, S., Guy, T. S., Halpern, A. L., Harrington, C., Hlci, T. N., Kidane, B., Olive, J. K., Ouzounian, M., Stamp, N., Vervoort, D., Varghese, T. K., Antonoff, M. B. 2020

    View details for DOI 10.1016/j.athoracsur.2020.05.006

    View details for PubMedID 32425205

  • The Impact of Donor Gender on Heart Transplantation Outcomes - A Study of over 60,000 Patients in the United States Zhu, Y., Shudo, Y., Lingala, B., Elde, S., Woo, Y. ELSEVIER SCIENCE INC. 2020: S42
  • Racial and Sex Disparities Persist in Modern Cardiac Surgical Outcomes. Annals of surgery Elde, S. F., Woo, Y. J. 2020; 272 (4): 668

    View details for DOI 10.1097/SLA.0000000000004333

    View details for PubMedID 32932323

  • Transplantation Outcomes in Adults With Congenital Heart Disease Have Room to Grow. The Canadian journal of cardiology Elde, S. n., Woo, Y. J. 2019

    View details for DOI 10.1016/j.cjca.2019.11.016

    View details for PubMedID 32046908

  • Tailored Approach to Surgical Exposure Reduces Surgical Site Complications after Bilateral Lung Transplantation SURGICAL INFECTIONS Elde, S., Huddleston, S., Jackson, S., Kelly, R., Shumway, S., Loor, G. 2017; 18 (8): 929-935

    Abstract

    We evaluated the effects of tailoring the operative approach on major surgical site complications and outcomes in lung transplant recipients.Beginning in July 2013, bilateral lung transplants at a single institution were performed either through sternotomy or clamshell depending on proximity of hilar structures by computed tomography (CT), anticipated complexity, past surgical history, and surgeon experience. Patient demographics and outcomes were collected in the institution's Transplant Information Services (TIS). A major surgical site complication was defined as a sterile or infected incision requiring operative intervention.One hundred six bilateral lung transplants (68 via clamshell and 38 via median sternotomy) were performed between July 2013 and June 2016. Median sternotomy patients were older (mean age 55 vs. 50 y, p = 0.04), and less likely to have cystic fibrosis (5 [13%] vs. 19 [28%], p = 0.21) or diabetes (5 [13%] vs. 26 [38%], p = 0.01). There was no statistically significant difference in mean lung allocation score (LAS) (45 vs. 48, p = 0.39) and body mass index (BMI; kg/m2; 25.3 vs. 24.4, p = 0.29) between the sternotomy and clamshell group. Fifteen (14.2%) patients experienced a total of 25 surgical site complications (19 major and 6 minor). No sternotomy patient had a major surgical site complication and 11 (16.2%) clamshell patients had a major surgical site complication (p = 0.01). Of these 11 patients, 5 (45%) required multiple operative revisions related to the surgical site. Freedom from major surgical site complications at three years was 100% for sternotomy patients and 80% for clamshell patients (p = 0.017).Tailoring the operative approach can reduce surgical site complications in lung transplant patients by avoiding a clamshell whenever feasible.

    View details for DOI 10.1089/sur.2017.144

    View details for Web of Science ID 000414908600014

    View details for PubMedID 29053438