Donor Hearts For Transplantation Research Articles

Change Of Heart: Interesting Case Of An Impella 5.5 Device Precipitating Electrical Storm And Right Ventricular Failure Treated With A Heart Transplant

<h3>Introduction</h3> Electrical storm (ES) due to ventricular arrhythmias is a life-threatening condition requiring emergent medical and mechanical intervention. <h3>Case</h3> A 60-year-old man with a history of nonischemic cardiomyopathy and ventricular tachycardia (VT) on sotalol and remote implantable-cardioverter implantation (ICD), already listed for transplant was admitted for shortness of breath at rest and worsening lower extremity edema. Physical examination; jugular venous pressure (JVP) of 12cm H₂O, S3 gallop, bibasilar rales on chest auscultation, and bilateral lower extremity edema with warm extremities. A right heart catheterization revealed a cardiac index of 1.6 with elevated filling pressures and blood pressure of 80s/50s mmHg. EKG showed chronic left bundle branch block with 1^st degree AV block. TTE reported severe MR and LVEF of 15 %. Sotalol was discontinued and IV diuretics with vasopressor support were attempted, but recalcitrant cardiogenic shock (approximately18 hours later) required escalation to mechanical support via Impella 5.5. Subsequently, i.e., 36 hours after Impella placement, the patient had multiple episodes of incessant VT requiring more than 20 ICD shocks complicated by cardiovascular collapse <b>(Figure 1)</b>. The patient was emergently intubated, deeply sedated, and initiated on Amiodarone and Lidocaine infusions (after bolus). Bedside TTE revealed evidence of RV failure with uncertainty regarding the distal tip of the Impella. He underwent emergent veno-arterial extracorporeal membrane oxygenation support (ECMO); transplant listing was upgraded to UNOS status I and he received a heart transplant within 24 hours. Post-operatively patient had no recurrence of VT and he was transferred to a skilled nursing facility 45 days later. <h3>Discussion</h3> Our case met the criteria for a ventricular or electrical storm as defined by 3 or more sustained episodes of VT/VF or appropriate ICD shocks within 24 hours. The etiology was deemed to be the nidus of severe structural heart disease <b>(Figure 2)</b> exacerbated by discontinuation of anti-arrhythmic and possible provocation of the myocardium by Impella. Appropriate interventions including combination IV antiarrhythmic agents, deep sedation, and ECMO were temporary measures deemed insufficient to curb the ES; therefore, transplant was the only best option. <h3>Conclusion</h3> ES may require emergent medical and drastic surgical interventions including ECMO. This case represents a unique clinical situation where the patient was essentially (and ultimately) "treated" with a donor heart transplant.

Transplant Outcomes in Hearts with Moderate to Severe Left Ventricular Hypertrophy After the 2018 OPTN/UNOS Allocation Changes

<h3>Purpose</h3> After the 2018 OPTN/UNOS heart transplant (HT) allocation changes, there has been an increase in graft ischemia time, a factor shown to worsen HT outcomes in recipients of hearts with left ventricular hypertrophy (LVH). We compare HT outcomes in moderate to severe LVH defined by left ventricular wall thickness ≥ 1.4cm and non-LVH hearts and determine if there were changes in LVH HT outcomes after 2018. <h3>Methods</h3> The UNOS database was queried for all HT recipients ages >18 from 2016 to 2020. Multi-organ transplants were excluded. Demographic, donor, and recipient information were compared between LVH and non-LVH hearts. The primary outcome was post-transplant survival with secondary outcomes of rejection, cardiac allograft vasculopathy (CAV), and post-transplant ejection fraction, all at one year. Comparisons were made using Chi-squared and Wilcoxon rank-sum. Multiple logistic and linear regression models were used to discern the predictors of survival and the effect of LVH on outcomes. <h3>Results</h3> 10,175 HTs were analyzed: 491 LVH and 9784 non-LVH. After the 2018 changes, compared to non-LVH HT donors, LVH HT donors were older, had higher BMI, more often had HTN, were male, and had kidney disease. LVH HT recipients were older, higher BMI, and had greater HLA mismatch. Graft ischemia time, survival, and secondary outcomes were similar. Examining the LVH cohort specifically before and after the 2018 changes, there were no differences in survival or most secondary outcomes (decrease in CAV) despite increases in recipient BMI, recipient prior cardiac surgery, and graft ischemia time, which were independent predictors of worse outcomes in the overall cohort. LVH was not a predictor of survival or any secondary outcome. <h3>Conclusion</h3> Outcomes for recipients of hearts with moderate to severe LVH were not negatively impacted by the 2018 OPTN/UNOS changes despite longer graft ischemia time, and outcomes for recipients of LVH hearts were similar to those receiving hearts without LVH.

Demographics and Utilization of Hepatitis C Hearts: A Single Center Experience

<h3>Purpose</h3> Since the advent of direct acting antiviral therapies as a cure for hepatitis C virus (HCV), the use of HCV nucleic acid test (NAT) positive donors in adult heart transplantation is increasing. The degree to which HCV NAT+ donor characteristics may impact donor selection remains unclear. We sought to explore the demographics and organ acceptance and transplantation rates of HCV NAT+ donor offers to our center, relative to those of other donor offers. <h3>Methods</h3> We used the United Network of Organ Sharing (UNOS) DonorNet database to evaluate 1,000 consecutive primary donor offers made to our center between January 1, 2018 and March 3, 2019. Statistical analysis was performed using ANOVA tests. <h3>Results</h3> Of 1,000 donor offers evaluated by our center, 238 were HCV antibody (Ab) positive of which 177 were HCV NAT positive. Compared to other donors, HCV NAT+ donors tended to be younger, male, and to die more often from drug overdose. Despite procurement teams having to travel longer distances to recover them, HCV NAT+ donors had higher rates of organ acceptance and ultimate transplantation relative to other donors. <h3>Conclusion</h3> Favorable demographic characteristics of HCV NAT+ donors are associated with higher rates of organ acceptance and transplantation at our center, despite longer procurement distances. Especially given the promising early outcomes among recipients of these donors, we anticipate that the rate of HCV NAT+ donor utilization will soon eclipse that of HCV naïve donor utilization nationwide.

The Impact of Utilizing DCD Donor Hearts on Heart Transplant Activity and Waitlist Time

<h3>Purpose</h3> Machine perfusion of donated organs after declaration of circulatory death (DCD) allows for the use of hearts previously discarded as not usable for transplantation. This opportunity potentially expands the donor pool and decreases waitlist time. This study aims to examine the impact of utilizing DCD hearts on heart transplant waitlist time <h3>Methods</h3> We retrospectively analyzed 161 patients who were listed for heart transplant from September 2019 through September 2021 at our center. These patients were separated into 2 periods centered on September 12, 2020 when transplantation of DCD donor hearts began <h3>Results</h3> Baseline patient characteristics were similar between both periods. In Period 1, 76 patients were waitlisted with 70 transplants occurring during this period, whereas in Period 2, 85 patients were waitlisted with 88 transplants occurring in this period. Thirty DCD donor heart transplants were performed in Period 2 (34% of period 2 transplants).Year over year transplant activity increased by 25.7%. Transplant rate increased from 2.06 person-year in Period 1 to 3.1 person-year in Period 2.There was no significant difference between the two periods with respect to waitlist mortality rate, length of post-transplant hospital stay, and short-term post-transplant survival. Median waiting time from listing to transplant was 17 days in Period 1 and 27 days in Period 2.There was no difference in blood types and United Network for Organ Sharing (UNOS) listing status between Period 1 and Period 2. <h3>Conclusion</h3> Our single-center analysis demonstrates that utilization of DCD donor hearts has resulted in an increase in transplant rate. Further extended follow-up is needed to determine long-term safety and efficacy of this strategy.

Aortic Root Thrombus Complicating Left Ventricular Assist Device Implantation

<h3>Introduction</h3> Aortic root thrombus (ART) is a recognized complication associated with left ventricular assist devices (LVADs) and is associated with significant morbidity and mortality. <h3>Case Report</h3> A 49 year-old male with recently diagnosed non-ischemic cardiomyopathy on inotropic support underwent HeartMate 3 implantation. He initially did well, but subsequently deteriorated and had altered mental status. CT head revealed vertebral artery thrombus and multiple ischemic changes. TEE showed large thrombus on aortic valve (AV) extending into the right coronary artery (RCA) despite therapeutic anticoagulation(Figure 1B). Hypercoagulable work up showed positive lupus anti-coagulant. He had progressive RV failure requiring right ventricular assist device as well as intractable ventricular fibrillation. Decision was made to list status 1 for heart transplant and suitable donor was identified within 72 hours. Post-operatively, unresponsive off sedation with dysconjugate gaze and minimal reflexes. Head CT showed extensive infarcts with swelling and mass effect. He was transitioned to comfort measures and compassionately extubated. <h3>Summary</h3> ART remains a rare, but significant complication post-implant despite improvements in contemporary LVADs. Pre-implant hypercoagulable workup in all patients has shown low utility. This case highlights the importance of intermittent AV opening and the significant complications that can occur in LVAD patients with ART.

Impact of Donor Hepatitis C Viremia on Acute Rejection in Heart Transplant Recipients

<h3>Purpose</h3> With the advent of direct acting antivirals, hepatitis C viremic donors are being increasingly used for heart transplantation. Single institutions have reported increased incidence of acute rejection when utilizing these hearts. The goal of this study was to evaluate one-year acute rejection following heart transplant from HCV viremic donors. <h3>Methods</h3> We conducted retrospective review of UNOS of all primary adult heart transplants conducted between March 31, 2015 and June 30, 2020, excluding recipients with prior transplants, multiorgan transplants, or those waitlisted for other organs. Donors were dichotomized as being HCV NAT+ or HCV NAT-. One-year acute rejection requiring treatment was compared and evaluated by univariable and multivariable logistic regression. <h3>Results</h3> Of 11,058 heart transplant recipients in our cohort during the study period, 432 (3.9%) came from HCV NAT+ donors. HCV NAT+ donors were significantly older (34±8 vs 32±11 years, p<0.01), more likely to be white (82% vs 64%, p<0.01), blood group O (61% vs 49%, p<0.01), CDC high risk (88% vs 30%, p<0.01), and have drug use as cause of death (61% vs 17%, p<0.01). Recipients in the HCV NAT+ group were older [58(49-64) vs 56 (46-63) years, p<0.01), had higher ischemic times (3.5±1.0 vs 3.1±1.1 hours, p<0.01) and were more likely to be blood group O (49% vs 39%, p<0.01) and HCV antibody positive (5% vs 2%, p<0.01). They were less likely to be on inotropes (31% vs 37%, p<0.01) or any life support (81% vs 86%, p<0.01) at the time of transplant. Incidence of acute rejection requiring treatment within one year was not significantly different between the two groups (21% HCV NAT+ vs 19% HCV NAT-, p = 0.31). Donor HCV NAT+ was not associated with one-year acute rejection on either univariable (OR 1.13, 95% CI 0.89-1.43) or multivariable (aOR 1.08, 95% CI 0.84-1.41) logistic regression. <h3>Conclusion</h3> Despite single center studies reporting potential increases in acute rejection when utilizing HCV-viremic donor hearts for transplantation, our UNOS registry analysis did not demonstrate increased treatment for acute rejection after one year. We should continue to utilize these donor hearts with careful surveillance and monitoring of long-term outcomes.

Incidence, Predictors, and Reversibility of Left Ventricular Dysfunction After Brain Death: The Donor Heart Study

<h3>Purpose</h3> Left ventricular (LV) dysfunction after brain death often prompts non-use of potential donor hearts for transplant, but little is known regarding its incidence, reversibility, and impact on outcomes. Shedding light on these unknowns was a primary aim of the Donor Heart Study -a first-of-its-kind, multisite, prospective study of potential heart donors. <h3>Methods</h3> We enrolled potential donors (n = 4333) at 8 organ procurement organizations across the United States from February 2015-May 2020. Data were collected on donor management, serial labs, and diagnostic tests. These included a transthoracic echocardiogram (TTE) performed within 48 hours after brain death and, if LV dysfunction was present, a repeat TTE 24 ± 6 hours later. LV dysfunction was defined as an ejection fraction (LVEF)<50%, as ascertained by a single expert reviewer, and was considered reversible if LVEF was >50% on the second TTE. LASSO models identified predictors of initial LV dysfunction and its reversibility. A conditional inference ("decision") tree was fit to identify threshold values that predict reversibility. <h3>Results</h3> An initial TTE was performed and interpretable for 3794 donors, and 493 (13%) had LV dysfunction. Significant predictors of LV dysfunction included: higher levels of troponin, nt-pro B-type natriuretic peptide (nt-proBNP), and lactate; higher mean arterial pressure, body temperature, use of vasopressors, and thyroid hormone; younger age; low body mass index (BMI≤ 20 kg/m2); and elevated blood urea nitrogen:creatinine ratio. A second TTE was performed for 224 donors with LV dysfunction and 130 (58%) of these demonstrated reversibility. Donors with baseline nt-proBNP levels >11,137 pg/ml were less likely to have LVEF improvement (30% vs 62%, p=0.008). Low BMI and reductions in serial nt-proBNP and lactate levels were the strongest predictors of reversibility. 59% of donor hearts with normal LV function were accepted for transplant, compared to 47% with reversible dysfunction and 29% with persistently low LVEF. <h3>Conclusion</h3> LV dysfunction after brain death is common among potential heart donors, but is reversible in the majority of cases. Commonly measured clinical variables are predictive of LV dysfunction and its subsequent improvement. Our results can better inform decisions made during donor management and evaluation, and can help guide donor heart acceptance.

Increasing Utilization of Extended Criteria Donor After Brain Death (DBD) Hearts Seldomly Used for Transplantation in the U.S. Due to Limitation of Ischemic Cold Storage - 2-Year Results of the OCS Heart EXPAND Prospective Multi-Center Trial (OCS Heart EXPAND)

<h3>Purpose</h3> To evaluate the effectiveness of the OCS Heart perfusion technology to preserve and assess extended criteria DBD hearts that are seldomly transplanted due to limitations of ischemic cold storage. <h3>Methods</h3> OCS Heart EXPAND targeted DBD hearts with one or more of the following risk factors: expected cross clamp time of ≥4 hours; OR expected cross-clamp time of ≥ 2 hours with one or more of the following risk factors: Older donors age 45-55 years with no coronary cath. Or ≥ 55 years old; history of cardiac downtime ≥20 min with stable hemodynamics at time of offer; history of LVH with septal or posterior wall thickness between 13-16 mm; LVEF 40-50%; or history of diabetes, or carbon monoxide poisoning or non-specific angiogram irregularities with no significant CAD. Given the extended criteria nature of the donor hearts that were used in the EXPAND trial, it was not feasible to randomize these donor hearts to cold storage preservation given the associated clinical risks. For benchmarking, clinical outcomes from the OCS Heart EXPAND trial were compared to clinical outcomes of standard criteria heart transplants obtained from UNOS/SRTR database performed at the same EXPAND centers over the same period of trial enrollment. <h3>Endpoints</h3> Patients were followed up-to 2 years post-transplant and compared to the survival data obtained from UNOS for all standard criteria heart transplants from the same transplant centers (Concurrent Controls). <h3>Results</h3> OCS Heart EXPAND and its continued access protocol enrolled a total of 138 extended criteria donor hearts that were perfused and assessed on the OCS Heart System between 2015 and 2020; of those 116/138 were successfully transplant and analyzed for a utilization rate of 84%. Over the same period, there were 1,813 Concurrent Control standard criteria DBD heart transplants. Given that EXPAND trial enrolled extended criteria hearts, there were statistically significant differences in donor risk factors between EXPAND vs Concurrent Controls obtained from UNOS/SRTR (see table below). EXPAND Trial transplanted donor hearts that refused on average 60 times in UNOS match run before being accepted by an EXPAND trial center. The Kaplan-Meier 2-year patient and graft survival results were comparable between the two comparator arms: patient survival – EXPAND OCS 85.3% vs Control standard criteria hearts 87.8% SOC (p=0.8893), graft survival – EXPAND OCS 94.2% vs Control standard criteria hearts 95%.Donor CharacteristicsEXPAND Trial (N=116)Concurrent Controls* (N=1813)p-valueAge (years) – mean ± SD37.1 ± 11.833.5 ± 11.40.0010Age ≥ 55 years12 (10.3%)84 (4.6%)0.0128LV Ejection Fraction58.2 ± 8.461.5 ± 6.5<0.0001LVH >12 ≤ 16 mm22 (19.0%)Not collectedCross-clamp time ≥ 4 hours (Expected)53 (45.7%)268 (14.8%)< 0.0001Cross-clamp time ≥ 4 hours (Actual)113 (97.4%)268 (14.8%)< 0.0001LVEF between 40% - 50%27 (23.3%)93 (5.1%)< 0.0001Downtime ≥ 20 minutes33 (28.4%)69 (3.8%)< 0.0001⁎data from 2015-2022 SRTR heart transplant registry <h3>Conclusion</h3> The use of OCS Heart system resulted in significantly high utilization of extended criteria DBD hearts that are seldomly used for transplants in the U.S. due to limitations of cold storage. The 2-year patient and graft survival outcomes are comparable to standard criteria heart transplant outcomes in the U.S. These results provide prospective clinical evidence that extended criteria DBD donor hearts should be considered to increase transplantation rates.

Heart Transplant Recipients of Donors with Intracranial Hemorrhage Have Worse Survival

<h3>Purpose</h3> A significant proportion of heart transplant donors suffer death from intracranial hemorrhage. We sought to determine if recipients of donors who die due to intracranial hemorrhage have worse outcomes post heart transplant. <h3>Methods</h3> The United Network for Organ Sharing database was queried from 2006 to 2020 for all adult recipients who underwent heart transplant. Survival was compared for recipients of donors with intracranial hemorrhage versus all other causes of death. Recipients were then identified if the donor cause of death was cerebrovascular, stroke or head trauma. Survival was compared for recipients of donors with intracranial hemorrhage and donors with nonhemorrhagic stroke or head trauma within this sub-group. <h3>Results</h3> A total of 31,599 patients underwent heart transplant during the study time period, with 6362 patients whose donor died due to intracranial hemorrhage. A total of 15,914 patients received a heart from a donor with an intracranial cause of death. Demographic information is shown in table 1. Survival was significantly worse for recipients of donors who died from intracranial hemorrhage (Figure 1, p<0.001). When survival was compared for recipients whose donor had an intracranial cause of death, intracranial hemorrhage resulted in worse survival compared with a nonhemorrhagic cause of death (p<0.001). Analysis of the cause of death showed a higher rate of graft failure in recipients of donors with intracranial hemorrhage (N=257, 13.4% vs. N=699, 11.9%, p<0.001). <h3>Conclusion</h3> Donors who die from intracranial hemorrhage should be considered with caution and should be matched carefully with the appropriate recipient.

Preserved Post-transplant Survival in Highly Sensitized Patients Who Received Hepatitis C NAAT Positive Allografts. A UNOS Database Analysis

<h3>Introduction</h3> Highly sensitized heart transplant candidates have a longer waitlist time, worse waitlist outcomes and often require higher levels of immunosuppression post-transplantation. Expanding the heart transplant donor pool with Hepatitis C NAAT positive (Hep C NAAT (+)) donors could increase the chances of transplantation in highly sensitized patients. The effects of sensitization on post-transplant outcomes in patients who received Hep C NAAT (+) donor allografts is unknown. <h3>Methods</h3> Adult patients who received HT from a Hep C NAAT (+) donor, between May 2015 and Dec 2020, were identified from the United Network for Organ Sharing (UNOS) database. These patients were classified according to the percentage of panel reactive antibody (PRA): Non-sensitized (0%), mildly sensitized (0%-20%), Moderately sensitized (21%-50%), and highly sensitized (>50%). Clinical characteristics and post-transplant survival were compared between groups. <h3>Results</h3> A total of 831 patients received HT from a hep C NAAT (+) donor during the study period. Of these 605 (72.8%), 88 (10.6%), 70 (8.4%) and 68 (8.2%) patients were non-sensitized, mildly sensitized, moderately sensitized, and highly sensitized, respectively. Highly sensitized patients were more likely to be women and African American. The 360-day post-transplant survival was 90.8%, 92.1%, 92.7%, 93% for the non-sensitized, mildly, moderately, and highly sensitized groups, respectively (p =ns). The frequency of graft failure (p= 0.97), acute rejection (p=0.193) and coronary vasculopathy (p=0.51) were similar among groups. <h3>Conclusions</h3> Highly sensitized patients who received Hepatitis C NAAT positive allografts have similar post-transplant survival than non-sensitized patients. Thus, highly sensitized patients should not be excluded from the donor pool expansion offered by hepatitis C NAAT positive donors.

Plasma Proteome of Brain-Dead Organ Donors as a Predictor of Graft-Related Outcomes After Heart Transplantation

<h3>Purpose</h3> Most solid organ transplantations are performed using organs from brain-dead donors. The inflammatory, cardiovascular, hormonal, and metabolic changes related to brain death may affect the quality of the transplanted organs and expose the recipients to pathological changes. We aimed to systemically characterize the plasma proteome of brain-dead heart transplant donors and to search for donor plasma proteins that would be related to graft-related outcome. <h3>Methods</h3> Plasma samples from 53 human brain-dead donors were analyzed by label-free protein quantification using high-definition mass spectrometry. Uni-and multivariate analyses were applied to determine potential proteome differences between brain-dead donors and healthy controls (n=24), and the enriched biological pathways were analyzed. Individual donor protein levels were correlated with clinical transplant outcomes, and predictive donor scores using the significant proteins were constructed. <h3>Results</h3> Uni-and multivariate analyses revealed that brain-dead donors have a distinct plasma proteome, with the levels of 237 of 463 proteins being changed compared to healthy controls. Significant pathways included upregulated coagulation, gluconeogenesis and glycolysis, and downregulated complement, LXR/RXR and production of nitric oxide and reactive oxygen species in macrophages. Lysine-specific demethylase 3A was moderately correlated with any grade and severe PGD in point-biserial correlation. Myosin Va and proteasome activator complex subunit 2 were significantly associated with acute rejections with hemodynamic compromise within 30 days in univariate and multivariate Cox regression analyses. Furthermore, lysine-specific demethylase 3A and moesin were associated with worse graft-related 1-year survival in univariate analysis. <h3>Conclusion</h3> Our detailed analysis revealed that brain death significantly altered plasma proteome. We further discovered altered donor protein signatures that are related to pathological changes such as cardiomyocyte and endothelial dysfunction, inflammation, and vascular growth and arteriogenesis, and correlate with clinical post-transplant outcomes. The current study can be leveraged to discover predictive donor protein signatures in future cohorts, which may lead to biomarker discovery for better donor organ evaluation.

Donor Simvastatin Treatment is More Effective in Donors with Low Plasma Levels of Arginine

<h3>Purpose</h3> Brain death may lead to a severe impairment of endothelial function and affect graft function. Recent study shows that simvastatin treatment to the organ donor decreases plasma biomarker levels of myocardial injury and heart failure and reduces the number of acute rejection episodes with hemodynamic compromise early after heart transplantation. However, the mechanisms of donor simvastatin treatment remain unknown. Therefore, we analyzed the plasma metabolomics of brain-dead heart transplant donors with or without simvastatin treatment to examine the molecular background of the beneficial effects. <h3>Methods</h3> In a prospective, double-blinded randomized controlled trial, 84 multiorgan donors were randomly assigned to receive either 80 mg of simvastatin (n=42) via nasogastric tube or to receive no simvastatin (n=42). Plasma samples from 84 human brain-dead multi-organ donors were collected immediately before organ procurement. We profiled over 100 targeted metabolites using mass spectrometry. <h3>Results</h3> We found that arginine and tryptophan were weakly negatively correlated with simvastatin treatment. Univariate Cox regression analysis showed that low levels of arginine were significantly associated with acute rejection and graft-related mortality (Figure 1 A,B). Additionally, we saw that donor simvastatin treatment significantly reduced the number of acute rejections by 41% (p=0.012) in low arginine group within the first year (Figure 1C). There was no difference in donor demographics between the groups. However, there was a statistically significantly higher need for mechanical circulatory support for hearts from donors with low arginine levels. <h3>Conclusion</h3> This study shows that donor simvastatin treatment could be more efficient in brain-dead heart transplant donors with low arginine. Further analysis will be conducted by exploring the interplay between arginine and simvastatin in detail. The complete results will be presented at the ISHLT2022 congress.

Heart Transplantation from Donation After Circulatory Death Donors: An Update on the Australian Experience

<h3>Purpose</h3> With an expanding end-stage heart failure population the demand for donor hearts is increasing. Donation after circulatory death (DCD) is a pathway that could help address this; we explore the impact of DCD over the last 8-years on our unit and compare our early vs contemporary outcomes. <h3>Methods</h3> All DCD heart transplants at our unit were included. Inclusion criteria for DCD donors are: normal transthoracic echo, age <55yrs & nil previous cardiac history. DCD heart retrievals are subject to varying functional (when systolic blood pressure drops <90mmHg) and asystolic warm ischemic times (aWIT) prior to administration of cardioplegia - this warrants an assessment of viability through visual inspection and monitoring of lactate levels. Donor hearts are cannulated onto an ex-vivo normothermic machine perfusion device where 1.2-1.5L of donor blood is circulated in a Langendorff fashion. <h3>Results</h3> Since 2014 we have performed 69 DCD heart transplants. Since 2020, DCD donors account for 32% of our heart transplant activity (32/100). Overall 1yr & 5yr survival for DCD vs BD donor heart transplant recipients was not significantly different (p=0.27). In the early experience, 12/34 patients (35.3%) required immediate post-operative ECMO or mechanical support. Recent recipients have a significantly lower rate with 3/35 (8.57%) requiring ECMO/mechanical support post-transplant (p=0.009). Mean DCD donor & recipient age was 32.6yrs(+/-10.5yrs) & 53.6yrs(+/-12.7yrs) respectively. Mean donor aWIT was 12.3mins (+/-2.8mins). Recipients of donors with an aWIT >15mins had significantly higher post-transplant ECMO/mechanical support requirement compared to those with an aWIT <=15mins (66.17% vs 17.46%, p=0.0177, OR 9.455). Median hospital length of stay was 17.5days (11-27.5days). <h3>Conclusion</h3> DCD donors can contribute to heart transplantation activity with survival comparable to BD pathways. Donor hearts subject to an aWIT >15mins are more likely to require post-operative ECMO/mechanical support.

Normothermic Regional Perfusion in Cardiac Transplantation: Developing a Program

<h3>Purpose</h3> Due to donor heart scarcity, heart failure patients are placed on a waitlist for transplantation. Efforts to expand the donor pool are essential to reduce waitlist mortality and add quality of life years. To increase organ utilization and transplantation our institution focused on innovations to allow DCD donor heart transplantation. Our program began utilizing DCD hearts in August 2020 as part of a clinical trial assessing direct procurement and machine perfusion technology. Following research on Normothermic Regional Perfusion (NRP) for DCD organ procurement and assessment, we established a clinical team to utilize this procurement strategy. <h3>Methods</h3> Our NRP program development was led by the Surgical Director and consisted of advanced heart failure fellows, transplant Nurse Practitioner, and transplant recovery specialists. The NRP program was developed in 4 phases. Phase 1: Research and concept development, IRB and and ethics review, and administration approval of NRP. Phase 2: NRP protocol development, donor acceptance criteria, and transportation logistics. Phase 3: Development of mobile cardio-pulmonary bypass system including supplies, specialized training, and construction of NRP procurement team consisting of five trained professionals. Phase 4: Dissemination of NRP protocols and focused education session for OPO and transplant center personnel. After completion of the first NRP heart transplant, all OPO leadership within our DSA were notified of our NRP program activation. <h3>Results</h3> The first remote NRP cardiac case was performed in May 2021 within our local DSA yielding a successful transplant. Our program year to date has completed 28 NRP procurement donor runs; yielding 20 transplants, with 8 aborted (6 did not expire, 1 decline due to quality, and 1 declined due to logistical issues). At present our program has 100% NRP transplant survival and our our annual transplant activity increased by 38%. <h3>Conclusion</h3> The structured development of an NRP program increased transplant volume with excellent short-term outcomes by utilizing previously discarded donor hearts.

Changes in echocardiographic parameters of the donor's heart before and after heart transplantation and their relationship with post-transplant survival.

BackgroundHeart transplantation is now widely performed in China, but the current entry criteria for heart transplantation donors are simple and lack reliable standards; there are still no studies on the effect of preoperative echocardiographic parameters of heart transplantation donors on the prognosis of the recipient. Therefore, the aim of this study is twofold: (I) to observe the characteristics of changes in echocardiographic parameters of the donor’s heart before and after heart transplantation and (II) to study the relationship between the changes in echocardiographic parameters of the donor’s heart pre- and post-transplant and transplant recipient survival.MethodsA total of 29 patients who underwent orthotopic heart transplant in our hospital from October 2016 to October 2019 were enrolled in this study. All recipients were followed up until April 2020. Echocardiographic data were collected pre-transplantation (donor) and at 1 week and 1 month post-transplant (recipient).ResultsCompared with the pretransplanted donor’s heart, there was an increase in the interventricular septal diameter, left ventricular posterior wall diameter, right atrium diameter and right ventricular diameter, while a decrease was found in the tricuspid annular systolic displacement and tricuspid annular peak systolic velocity at 1 week post-transplant. The survival curve showed that the postoperative survival time in the right atrium/ventricle ≥32 mm group was better than that in the right atrium/ventricle <32 mm group. The survival curve also showed that the postoperative survival time in the right atrium/ventricle enlargement <2 mm group was better than that in the right atrium/ventricle enlargement ≥2 mm group.ConclusionsIn the early post-transplant period, ventricular myocardial thickening, right heart enlargement and a decrease in right heart function were observed in the post-transplanted heart compared to the pretransplanted donor’s heart. Postoperative survival was higher among heart transplant patients who received a heart with right atrium/ventricle ≥32 mm. Postoperative survival was lower among heart transplant patients whose right atrium/ventricle was dilated ≥2 mm at 1 month postoperatively compared with the pretransplanted donor’s heart.

Matching Donor and Recipient Size in Pediatric Heart Transplantation.

Previous analyses in pediatric heart transplant (HT) recipients using weight or height have not found donor-recipient size-mismatch to be associated with post-transplant mortality. A recent study in 3,215 normal US children developed an equation for left ventricular (LV) mass using body surface area (BSA). We assessed whether donor-recipient size match using predicted LV mass (PLM) is associated with post-transplant in-hospital mortality or 1-year graft survival. We identified 4,717 children <18yrs old who received primary HT in the US during 01/2000 to 03/2015 and divided them into five groups [10%, 10%, 60% (reference group), 10% and 10%, respectively] with increasing donor-recipient PLM ratio. In adjusted analysis, group 1 children (PLM ratio ≤.90) were at higher risk of post-transplant in-hospital mortality [Odds Ratio (OR) 1.55, 95% CI 1.04, 2.31]. This association of the most undersized donors with recipient in-hospital mortality was similar when donor-recipient weight ratio<.88 or BSA ratio<.92 (lowest decile) were used instead. There was no difference in 1-year graft survival among groups. Utilizing donors with donor-recipient PLM ratio ≤.90 is associated with higher risk of early post-transplant mortality in pediatric HT recipients. However, this metric is not superior to donor-recipient weight ratio or BSA ratio for assessing size match.

Heart Xenotransplant: A Door That Is Finally Opening.

Heart Xenotransplant: A Door That Is Finally Opening.

Donation after circulatory death heart transplantation in the United States: An early report of donor characteristics.

In the United States, heart transplantation continues to be constrained by a limited supply of donor organs. Over the past decade, we have seen a dramatic rise in the number of candidates listed for heart transplantation, with the number of transplants performed increasing, although at a lesser rate.1 A multitude of efforts are being undertaken to increase the size of the donor pool, including the transplantation of expanded-criteria donor hearts, the use of normothermic ex vivo perfusion techniques, as well as a renewed interest in transplanting hearts following donation after circulatory death (DCD).

Treatment of advanced heart failure

Background: The development of medical and device treatment of heart failure (HF) has improved the survival and quality of life in HF patients. However, not all HF patients respond well to these up-to-date HF treatments. We have termed these non-responders as advanced HF patients. The definition, diagnosis, and treatment of advanced HF are discussed in this review article.Current Concepts: After current guideline-directed treatments, advanced HF patients can experience aggravation and decompensation, usually resulting in hospitalization for the symptoms and volume control. Recurrent decompensation or hospitalization can cause a vicious cycle between the heart and other vital organs, such as the kidney and liver. Current and up-to-date guidelines recommend treatments, including heart transplant, left ventricular assist device (LVAD), and hospice care, for advanced HF. Given the limitation of heart transplant donors, LVAD can be used as a bridge to transplant, in addition to destination therapy. Updated LVAD system can reduce pump-related thrombosis, stroke, and bleeding.Discussion and Conclusion: Current guidelines suggest early recognition of advanced HF and referral to advanced HF specialists. Despite advances in the treatments of advanced HF, unmet needs for further improving clinical outcomes and quality of life exist.

Outcomes following use of pediatric and young adult donor hearts with bicuspid aortic valves: A single‐center case series

Valvular disease in pediatric and young adult donor hearts may be a relative contraindication to graft use. Outcomes following the use of donor hearts with bicuspid aortic valve (BAV) have not been previously reported in children. We describe 4 cases of pediatric heart transplantation (HTx) utilizing a donor heart with a BAV. Of the 469 HTx included in this study, 4 utilized a donor heart with a BAV. All recipients were female; median age was 11years (range 0.3 to 19years). In all cases, the BAV was not discovered until after HTx. All donors were less than 30years old. The patients were followed for a median of 6years (range 2 to 9years) with all patients alive at last follow-up. Two patients have transitioned to adult care, and 2 patients continue to follow in our clinic. In follow-up, no patient has required an aortic valve intervention or had infective endocarditis. At last review, no patient had greater than mild aortic insufficiency or more than mild aortic stenosis. Three patients developed mild-to-moderate left ventricular hypertrophy in the first year post-transplant that improved over time. One patient experienced a peri-operative embolic stroke at time of transplant unrelated to the BAV. On short- and intermediate-term follow-up, pediatric and young adult donor hearts with BAV demonstrated acceptable graft longevity and valvular function. A functionally normal BAV in a pediatric heart transplant donor should not be a contraindication to organ acceptance.