Sex as a biological variable: Mechanistic insights and clinical relevance in solid organ transplantation.

Biological sex affects immunity broadly, with recognized effects on the incidence and severity of autoimmune diseases, infections, and malignancies. Consequences of sex on alloimmunity and outcomes in solid organ transplantation are less well defined. Clinical studies have shown that donor and recipient sex independently impact transplant outcomes, which are further modified by aging. Potential mechanisms have thus far not been detailed and may include hormonal, genetic, and epigenetic components. Here, we summarize relevant findings in immunity in addition to studies in clinical and experimental organ transplantation detailing the effects of biological sex on alloimmunity. Understanding both clinical impact and mechanisms is expected to provide critical insights on the complexity of alloimmune responses, with the potential to fine-tune treatment and allocation while providing a rationale to include both sexes in transplant research.

PCSK9 inhibitors safely and effectively lower LDL after heart transplantation: a systematic review and meta-analysis.

Coronary allograft vasculopathy (CAV) continues to afflict a high number of heart transplant (HT) recipients, and elevated LDL is a key risk factor. Many patients cannot tolerate statin medications after HT; however, data for alternative agents remains scarce. To address this key evidence gap, we evaluated the safety and efficacy of the PCSK9i after HT through systematic review and meta-analysis. We searched Medline, Cochrane Central, and Scopus from the earliest date through July 15th, 2021. Citations were included if they were a report of PCSK9i use in adults after HT and reported an outcome of interest. Outcomes included change in LDL cholesterol from baseline, incidence of adverse events, and evidence of CAV. Changes from baseline and outcome incidences were pooled using contemporary random-effects model methodologies. A total of six studies including 97 patients were included. Over a mean follow-up of 13 months (range 3-21), PCSK9i use lowered LDL by 82.61 mg/dL (95% CI - 119.15 to - 46.07; I2 = 82%) from baseline. Serious adverse drug reactions were rarely reported, and none was attributable to the PCSK9i therapy. Four studies reported stable calcineurin inhibitor levels during PCSK9i initiation. One study reported outcomes in 33 patients with serial coronary angiography and intravascular ultrasound, and PCSK9i were associated with stable coronary plaque thickness and lumen area. One study reported on immunologic safety, showing no DSA development within 1 month of therapy. Preliminary data suggest that long-term PCSK9i therapy is safe, significantly lowers LDL, and may attenuate CAV after HT. Additional study on larger cohorts is warranted to confirm these findings.

Prolonged severe acute respiratory syndrome coronavirus 2 persistence, attenuated immunologic response, and viral evolution in a solid organ transplant patient.

Unlike immunocompetent hosts, the duration of viral persistence after infection with severe acute respiratory syndrome coronavirus 2 can be prolonged in immunosuppressed patients. Here, we present a case of viral persistence for over 19 weeks in a patient with a history of solid organ transplant and explore the clinical, virologic, and immunologic course. Our patient still demonstrated viral persistence at 138 days with low polymerase chain reaction cycle threshold values and evidence of continuing viral sequence evolution indicative of ongoing virus replication. These findings have important implications for infection prevention and control recommendations in immunosuppressed patients. Immune response, including neutralizing antibody titers, T cell activity, and cytokine levels, peaked around days 44-72 after diagnosis. Anti-S trimer antibodies were low at all time points, and T cell response was attenuated by day 119. As immune response waned and viral load increased, increased genetic diversity emerged, suggesting a mechanism for the development of viral variants.

Chronic intermittent intravenous immunoglobulin in heart transplant recipients with elevated donor-specific antibody levels.

Donor-specific antibodies (DSA) are associated with antibody-mediated rejection (AMR) and poor patient survival. In heart transplant, the efficacy of intermittent intravenous immunoglobulin (IVIg) in reducing de novo DSA levels and treating AMR has not been characterized. We retrospectively studied a cohort of 19 patients receiving intermittent IVIg for elevated DSA and examined changes in DSA levels and graft function. Intermittent IVIg infusions were generally safe and well tolerated. Overall, 23 of 62 total DSA (37%) were undetectable after treatment, 21 DSA (34%) had MFI decrease by more than 25%, and 18 (29%) had MFI decrease by less than 25% or increase. The average change in MFI was -51% ± 71% (P < .001). Despite reductions in DSA, among the six patients (32%) with biopsy-confirmed AMR, left ventricular ejection fraction (LVEF) decreased in five (83%) and cardiac index (CI) decreased in three (50%). Conversely, LVEF increased in 91% and CI increased in 70% of biopsy-negative patients. All six AMR patients were readmitted during treatment, four for confirmed or suspected rejection. IVIg infusions may stabilize the allograft in patients with elevated DSA and negative biopsies, but once AMR has developed does not appear to improve allograft function despite decreasing DSA levels.

From bench to bedside: reversing established antibody responses and desensitization.

PURPOSE OF REVIEW: Basic transplant immunology has primarily focused on the definition of mechanisms, but an often-stated aspirational goal is to translate basic mechanistic research into future therapy. Pretransplant donor-specific antibodies (DSA) mediate hyperacute as well as early antibody-mediated rejection (AMR), whereas DSA developing late posttransplantation may additionally mediate chronic rejection. Although contemporary immunosuppression effectively prevents early cellular rejection after transplant in nonsensitized patients, it is less effective at controlling preexisting HLA antibody responses or reversing DSA once established, thus underscoring a need for better therapies. RECENT FINDINGS: We here review the development of a bench-to-bedside approach involving transient proteasome inhibition to deplete plasma cells, combined with maintenance co-stimulation blockade, with CTLA-4Ig or belatacept, to prevent the generation of new antibody-secreting cells (ASCs). SUMMARY: This review discusses how this treatment regimen, which was rationally designed and validated to reverse established DSA responses in mouse models, translated into reversing active AMR in the clinic, as well as desensitizing highly sensitized patients on the transplant waitlist.

T cell repertoire analysis suggests a prominent bystander response in human cardiac allograft vasculopathy.

T cells are implicated in the pathogenesis of cardiac allograft vasculopathy (CAV), yet their clonality, specificity, and function are incompletely defined. Here we used T cell receptor ß chain (TCRB) sequencing to study the T cell repertoire in the coronary artery, endomyocardium, and peripheral blood at the time of retransplant in four cases of CAV and compared it to the immunoglobulin heavy chain variable region (IGHV) repertoire from the same samples. High-dimensional flow cytometry coupled with single-cell PCR was also used to define the T cell phenotype. Extensive overlap was observed between intragraft and blood TCRBs in all cases, a finding supported by robust quantitative diversity metrics. In contrast, blood and graft IGHV repertoires from the same samples showed minimal overlap. Coronary infiltrates included CD4+ and CD8+ memory T cells expressing inflammatory (IFNγ, TNFα) and profibrotic (TGFß) cytokines. These were distinguishable from the peripheral blood based on memory, activation, and tissue residency markers (CD45RO, CTLA-4, and CD69). Importantly, high-frequency rearrangements were traced back to endomyocardial biopsies (2-6 years prior). Comparison with four HLA-mismatched blood donors revealed a repertoire of shared TCRBs, including a subset of recently described cross-reactive sequences. These findings provide supportive evidence for an active local intragraft bystander T cell response in late-stage CAV.

How can we better inform our patients about post-heart transplantation survival? A conditional survival analysis.

BACKGROUND: Conditional survival (CS) is a dynamic method of survival analysis that provides an estimate of how an individual's future survival probability changes based on time post-transplant, individual characteristics, and post-transplant events. This study sought to provide post-transplant CS probabilities for heart transplant recipients based on different prognostic variables and provide a discussion tool for the providers and the patients. METHODS: Adult heart transplant recipients from January 1, 2004, through October 18, 2018, were identified in the UNOS registry. CS probabilities were calculated using data from Kaplan-Meier survival estimates. RESULTS: CS probability exceeded actuarial survival probability at all times post-transplant. Women had similar short-term, but greater long-term CS than men at all times post-transplant (10-year CS 1.8-11.5% greater [95% CI 1.2-12.9]). Patients with ECMO or a surgical BiVAD had decreased survival at the time of transplant, but their CS was indistinguishable from all others by 1-year post-transplant. Rejection and infection requiring hospitalization during the first year were associated with a persistently decreased CS probability. CONCLUSIONS: In this study, we report differential conditional survival outcomes based on time, patient characteristics, and clinical events post-transplant, providing a dynamic assessment of survival. The survival probabilities will better inform patients and clinicians of future outcomes.

Extracorporeal photopheresis and its role in heart transplant rejection: prophylaxis and treatment.

Heart transplantation is the gold standard therapeutic option for select patients with end-stage heart failure. Unfortunately, successful long-term outcomes of heart transplantation can be hindered by immune-mediated rejection of the cardiac allograft, specifically acute cellular rejection, antibody-mediated rejection, and cardiac allograft vasculopathy. Extracorporeal photopheresis is a cellular immunotherapy that involves the collection and treatment of white blood cells contained in the buffy coat with a photoactive psoralen compound, 8-methoxy psoralen, and subsequent irradiation with ultraviolet A light. This process is thought to cause DNA and RNA crosslinking, ultimately leading to cell destruction. The true mechanism of therapeutic action remains unknown. In the last three decades, extracorporeal photopheresis has shown promising results and is indicated for a variety of conditions. The American Society for Apheresis currently recommends the use of extracorporeal photopheresis for the treatment of cutaneous T-cell lymphoma, scleroderma, psoriasis, pemphigus vulgaris, atopic dermatitis, graft-versus-host disease, Crohn's disease, nephrogenic systemic fibrosis, and solid organ rejection in heart, lung, and liver transplantation. In this review, we aim to explore the proposed effects of extracorporeal photopheresis and to summarize published data on its use as a prophylactic and therapy in heart transplant rejection.

Desensitizing highly sensitized heart transplant candidates with the combination of belatacept and proteasome inhibition.

HLA antibodies pose a significant barrier to transplantation and current strategies to reduce allosensitization are limited. We hypothesized that augmenting proteasome inhibitor (PI) based desensitization with costimulation blockade (belatacept) to mitigate germinal center (GC) responses might increase efficacy and prevent rebound. Four highly sensitized (calculated panel reactive antibody [cPRA] class I and/or II >99%, complement-dependent cytotoxicity panel reactive antibody [CDC PRA+], C1q+) heart transplant candidates were treated with the combination of belatacept and PI therapy, which significantly reduced both class I and II HLA antibodies and increased the likelihood of identifying an acceptable donor. Three negative CDC crossmatches were achieved against 3, 6, and 8 donor-specific antibodies (DSA), including those that were historically C1q+ binding. Posttransplant, sustained suppression of 3 of 3, 4 of 6, and 8 of 8 DSA (cases 1-3) was achieved. Analysis of peripheral blood mononuclear cells before and after desensitization in one case revealed a decrease in naïve and memory B cells and a reduction in T follicular helper cells with a phenotype suggesting recent GC activity (CD38, PD1, and ICOS). Furthermore, a shift in the natural killer cell phenotype was observed with features suggestive of activation. Our findings support synergism between PI based desensitization and belatacept facilitating transplantation with a negative CDC crossmatch against historically strong, C1q binding antibodies.

United network for organ sharing outcomes after heart transplantation for al compared to ATTR cardiac amyloidosis.

Light-chain (AL) cardiac amyloidosis (CA) has a worse prognosis than transthyretin (ATTR) CA. In this single-center study, we compared post-heart transplant (OHT, orthotopic heart transplantation) survival for AL and ATTR amyloidosis, hypothesizing that these differences would persist post-OHT. Thirty-nine patients with CA (AL, n = 18; ATTR, n = 21) and 1023 non-amyloidosis subjects undergoing OHT were included. Cox proportional hazards modeling was used to evaluate the impact of amyloid subtype and era (early era: from 2001 to 2007; late era: from 2008 to 2018) on survival post-OHT. Survival for non-amyloid patients was greater than ATTR (P = .034) and AL (P < .001) patients in the early era. One, 3-, and 5-year survival rates were higher for ATTR patients than AL patients in the early era (100% vs 75%, 67% vs 50%, and 67% vs 33%, respectively, for ATTR and AL patients). Survival in the non-amyloid cohort was 87% at 1 year, 81% at 3 years, and 76% at 5 years post-OHT. In the late era, AL and ATTR patients had unadjusted 1-year, 3-year, and 5-year survival rates of 100%, which was comparable to non-amyloid patients (90% vs 84% vs 81%). Overall, these findings demonstrate that in the current era, differences in post-OHT survival for AL compared to ATTR are diminishing; OHT outcomes for selected patients with CA do not differ from non-amyloidosis patients.

Advanced Therapies for Advanced Heart Failure in Women.

Women with advanced heart failure (HF) are underrepresented in trials of short-term and durable mechanical circulatory support although they derive similar benefit. In acute HF, intensive medical and interventional therapies are effective but underutilized. The smaller, newer generation, left ventricular assist devices (LVADs) have increased the feasibility of durable support in women. Women frequently present late, with more comorbidities, emphasizing the need for timely referral. Compared with men, the stroke risk is higher in women with an LVAD. Increased representation in clinical trials and a better understanding of the psychosocial issues affecting women is essential.

VA-ECMO for cardiogenic shock in the contemporary era of heart transplantation: Which patients should be urgently transplanted?

With the impending United Network for Organ Sharing (UNOS) heart allocation policy giving VA-ECMO supported heart transplant (HT) candidates highest priority status (Tier 1), identifying patients in cardiogenic shock (CS) with severe and irreversible heart failure (HF) appropriate for urgent HT is critically important. In a center where wait times currently preclude this approach, we retrospectively reviewed 119 patients (ages 18-72) with CS from 1/2014 to 12/2016 who required VA-ECMO for >24 hours. Underlying aetiologies included postcardiotomy shock (45), acute coronary syndromes (33), and acute-on-chronic HF (16). Eighty-four percent of patients (100) had ≥1 contraindication to HT with 61.3% (73) having preexisting contraindications (eg, multiorgan dysfunction and substance abuse), and 68.1% (81) experienced preclusive complications (eg, renal failure, coagulopathy, and infection). Potential HT candidates were significantly more likely to survive to discharge (potential HT candidates 84.2% vs preexisting contraindications 43.8% vs contraindications developing on VA-ECMO 33.3%, P = 0.001). Among potential HT candidates, 11 (68.8%) were discharged without advanced therapies and 4 received durable left ventricular assist device (25.0%). Importantly, 1-year survival was 100% for the 11 patients with follow-up. Thus, further work is critical to define appropriate candidates for HT from VA-ECMO while avoiding preemptive transplantation in those with otherwise favorable outcomes.

Heart rate in patients with reduced ejection fraction: relationship between single time point measurement and mean heart rate on prolonged implantable cardioverter defibrillator monitoring.

BACKGROUND: Heart rate (HR) is a prognostic marker that is increasingly used as a therapeutic target in patients with cardiovascular disease. The association between resting and mean HR remains unclear. We therefore set out to determine the relationship between resting HR on the electrocardiogram (ECG) obtained at a single time point, and mean HR on implantable cardioverter defibrillator (ICD) interrogation amongst patients with a reduced left ventricular ejection fraction (LVEF). METHODS: Prospective ICD data were obtained from 54 patients with LVEF < 40%. Mean HR determined using the ICD HR histograms was compared with resting HR measured on the ECG performed in the clinic. RESULTS: Average resting and ICD mean HRs were 67.9 ± 10.1 and 67.8 ± 9.6 bpm respectively. There was good correlation in the overall cohort (r = 0.79), in those with resting ECG HRs ≤ 70 bpm (r = 0.62), and amongst the 27 patients on intermediate-to-high dose beta-blockers (r = 0.91). However, Bland-Altman analysis demonstrated wide limits of agreement in the overall cohort (- 12.5, 12.7 bpm), at resting HRs ≤ 70 bpm (- 12.7, 9.8 bpm), and on intermediate-to-high dose beta-blockers (- 8.9, 7.4 bpm). Moreover, resting HR did not predict the 10-bpm interval where the most time was spent. CONCLUSIONS: While resting HR correlated with mean HR in patients with reduced LVEF, and in important subgroups, the limits of agreement were unacceptably wide raising concern over the use of single time point resting HR as a therapeutic target.

Impact of Pretransplant Malignancy on Heart Transplantation Outcomes: Contemporary United Network for Organ Sharing Analysis Amidst Evolving Cancer Therapies.

BACKGROUND: An aging population and improved cancer survivorship have increased the number of individuals with treated malignancy who develop advanced heart failure. The benefits of heart transplantation (HT) in patients with a pretransplant malignancy (PTM) must be balanced against risks of posttransplant malignancy in the setting of immunosuppression. METHODS: Adult patients in the United Network for Organ Sharing registry who received HT between January 1, 2010, and December 31, 2020 were included. Trends, patient characteristics, and posttransplant outcomes in HT recipients with PTM were evaluated. RESULTS: From 2000 to 2020, the proportion of HT recipients with PTM increased from 3.2% to 8.2%. From 2010 to 2020, 2113 (7.7%) of 27 344 HT recipients had PTM. PTM was associated with higher rates of 1-year mortality after HT (11.9% versus 9.2%; adjusted hazard ratio, 1.25 [95% CI, 1.09-1.44], P=0.001), driven by increased mortality in patients with hematologic PTM (adjusted hazard ratio, 2.00 [95% CI, 1.61-2.48]; P<0.001). For recipients who survived the first year, 5-year survival was similar between patients with and without PTM. Rates of malignancy at 5-years posttransplant were higher in the PTM group (20.4% versus 13.1%; adjusted hazard ratio, 1.57 [95% CI, 1.38-1.79], P<0.001). CONCLUSIONS: Prevalence of PTM in HT recipients nearly tripled over the past 2 decades. Patients with hematologic PTM were at increased risk of early mortality after HT. Patients with PTM were also at higher risk for posttransplant malignancy. Guidelines that reflect contemporary oncological care are needed to inform care of this heterogenous and expanding group of individuals.

De Novo Human Leukocyte Antigen Allosensitization in Heartmate 3 Versus Heartmate II Left Ventricular Assist Device Recipients.

Left ventricular assist devices (LVADs) are associated with the development of antihuman leukocyte antigen (HLA) antibodies, which can create a challenge for future transplantation in these patients. The differential effects of Heartmate 3 (HM3) versus Heartmate II (HMII) on de novo HLA allosensitization remain unknown. Patients who underwent HMII or HM3 implantation and had no prior HLA antibodies by solid-phase assay (Luminex) testing were included in this study. Complement-dependent cytotoxicity (CDC) panel reactive antibody (PRA) levels and Luminex antibody profiles were followed until cardiac transplantation, device explantation, or death. Electronic medical records were reviewed to examine posttransplant outcomes. Thirty-eight HM3 and 34 HMII patients with complete data were followed for 1.5 ± 1.1 years on device support. HM3 and HMII groups had similar age at implant, female gender, ischemic heart failure etiology, bridge strategy at implant, as well as intraoperative and postoperative transfusion requirements. 39.5% of HM3 and 47.1% of HMII patients developed detectable HLA antibodies by Luminex testing (p = 0.516). Development of high-level (mean fluorescence intensity >10,000) antibodies was significantly lower in HM3 than HMII patients (5.3 vs. 20.6%, p = 0.049). CDC PRA testing showed fewer HM3 patients with a positive result (PRA > 0%) than HMII patients (39.4 vs. 70.0%, p = 0.015). Among transplanted patients, those who had developed de novo sensitization on LVAD support showed a trend toward incidence of moderate to severe grade rejection compared with unsensitized patients (23.8 vs. 4.8%, p = 0.078). HM3 is associated with lower risk of de novo HLA sensitization compared with HMII.

Temporal shifts in safety and efficacy profile of mycophenolate mofetil 2 g versus 3 g daily early after heart transplantation.

STUDY OBJECTIVE: Mycophenolate mofetil (MMF) is the gold-standard immunosuppressive agent in heart transplantation (HT), but dose-dependent toxicities (e.g., neutropenia) are frequent. Gut bacteria ß-d-glucuronidases (GUS) modulate MMF bioavailability, and changes in the intestinal flora may influence the pharmacokinetics of MMF. The objective of this study was to evaluate the safety and efficacy of MMF 1.5 g every 12 h (q12) [high-dose, HD] versus 1 g q12 [low-dose, LD] and explore the association between neutropenia and GUS. MEASUREMENTS: We compared the incidence of acute cellular rejection (ACR) and neutropenia during the first 6 months post-HT. The association between neutropenia and GUS was investigated in an exploratory analysis on a subset of patients with prospectively collected stool data. Stool samples were analyzed using 16S rRNA sequencing. MAIN RESULTS: A total of 168 patients (120 MMF-HD, 48 MMF-LD; mean age 55.7 years, 79% male) were studied. Neutropenia occurred in 38.6% of patients at a median of 106 [64-143] days. Freedom from neutropenia was lower in MMF-HD compared with MMF-LD (57% vs. 73%, p = 0.03). ACR (≥1R/1B) occurred in 37.5% of patients at a median of 20 [10-96] days, while high-grade ACR (≥2R/3A) occurred in 11.3% at a median of 14 [9-89] days. Freedom from ACR was similar between groups. MMF-LD was associated with more high-grade ACR (hazard ratio [HR] 3.47, 95% confidence interval [CI] 1.09-11.08, p = 0.03) during the first month, but less neutropenia (HR 0.54, 95% CI 0.29-1.00, p = 0.05) between 1 and 6 months. GUS-producing bacteria were more abundant in neutropenic patients. CONCLUSIONS: MMF-LD was associated with higher rates of early high-grade ACR and lower rates of later neutropenia. Further studies are warranted to test whether temporal MMF dose adjustments and gut microbial composition could improve clinical outcomes post-HT.

Current Desensitization Strategies in Heart Transplantation.

Heart transplant candidates sensitized to HLA antigens wait longer for transplant, are at increased risk of dying while waiting, and may not be listed at all. The increasing prevalence of HLA sensitization and limitations of current desensitization strategies underscore the urgent need for a more effective approach. In addition to pregnancy, prior transplant, and transfusions, patients with end-stage heart failure are burdened with unique factors placing them at risk for HLA sensitization. These include homograft material used for congenital heart disease repair and left ventricular assist devices (LVADs). Moreover, these risks are often stacked, forming a seemingly insurmountable barrier in some cases. While desensitization protocols are typically implemented uniformly, irrespective of the mode of sensitization, the heterogeneity in success and post-transplant outcomes argues for a more tailored approach. Achieving this will require progress in our understanding of the immunobiology underlying the innate and adaptive immune response to these varied allosensitizing exposures. Further attention to B cell activation, memory, and plasma cell differentiation is required to establish methods that durably abrogate the anti-HLA antibody response before and after transplant. The contribution of non-HLA antibodies to the net state of sensitization and the potential implications for graft longevity also remain to be comprehensively defined. The aim of this review is to first bring forth select issues unique to the sensitized heart transplant candidate. The current literature on desensitization in heart transplantation will then be summarized providing context within the immune response. Building on this, newer approaches with therapeutic potential will be discussed emphasizing the importance of not only addressing the short-term pathogenic consequences of circulating HLA antibodies, but also the need to modulate alloimmune memory.

Exception Status Listing in the New Adult Heart Allocation System: A New Solution to an Old Problem?

BACKGROUND: One of the goals of the revised 6-tiered US adult heart allocation policy was to improve risk stratification of patients to lower exception status utilization for transplant listing. We sought to define the characteristics and outcomes of waitlisted patients using exception status and to examine region- and center-level differences in utilization of exception status in the new heart allocation system. METHODS: This retrospective cohort analysis of the United Network for Organ Sharing database included adult waitlisted patients for heart transplant between October 18, 2018, and June 30, 2020, in the United States, stratified by use of exception status versus standard criteria. RESULTS: Out of 6351 patients, 1907 (30.0%) were waitlisted under exception status. Patients using exception status were more likely to have a nonischemic cause of heart failure, blood type O, United Network for Organ Sharing status 2 at listing and were less likely to have a durable left ventricular assist device at listing. Exception status utilization varied significantly between and within United Network for Organ Sharing regions. Listing by exception criteria was associated with a significantly higher incidence of heart transplantation compared with listing by standard criteria (hazard ratio, 1.25 [1.15-1.38], P<0.001), without increased risk of death or delisting for worsening clinical status (hazard ratio, 0.83 [0.65-1.05], P=0.12) after multivariable adjustment. CONCLUSIONS: The status tiers of the new heart allocation system may not fully capture medical urgency and complexity of waitlisted patients as assessed by transplant physicians and review committees and may limit the ability to develop a heart allocation score.

Characteristics and Outcomes of Recipients of Heart Transplant With Coronavirus Disease 2019.

Importance: Recipients of heart transplant (HT) may be at increased risk of adverse outcomes attributable to infection with coronavirus disease 2019 (COVID-19) because of multiple comorbidities and clinically significant immunosuppression. Objective: To describe the characteristics, treatment, and outcomes of recipients of HT with COVID-19. Design, Setting, and Participants: This case series from a single large academic heart transplant program in New York, New York, incorporates data from between March 1, 2020, and April 24, 2020. All recipients of HT followed up by this center who were infected with COVID-19 were included. Interventions: Heart transplant and a confirmed diagnosis of COVID-19. Main Outcomes and Measures: The primary measure was vital status at end of study follow-up. Secondary measures included patient characteristics, laboratory analyses, changes to immunosuppression, and treatment administered for COVID-19. Results: Twenty-eight patients with HT received a confirmed diagnosis of COVID-19. The median age was 64.0 (interquartile range [IQR], 53.5-70.5) years, 22 (79%) were men, and the median time from HT was 8.6 (IQR, 4.2-14.5) years. Comorbid conditions included hypertension in 20 patients (71%), diabetes in 17 patients (61%), and cardiac allograft vasculopathy in 16 patients (57%). Twenty-two participants (79%) were admitted for treatment, and 7 (25%) required mechanical ventilation. Most (13 of 17 [76%]) had evidence of myocardial injury (median high-sensitivity troponin T, 0.055 [IQR, 0.0205-0.1345] ng/mL) and elevated inflammatory biomarkers (median peak high-sensitivity C-reactive protein, 11.83 [IQR, 7.44-19.26] mg/dL; median peak interleukin 6, 105 [IQR, 38-296] pg/mL). Among patients managed at the study institution, mycophenolate mofetil was discontinued in 16 patients (70%), and 6 (26%) had a reduction in the dose of their calcineurin inhibitor. Treatment of COVID-19 included hydroxychloroquine (18 patients [78%]), high-dose corticosteroids (8 patients [47%]), and interleukin 6 receptor antagonists (6 patients [26%]). Overall, 7 patients (25%) died. Among 22 patients (79%) who were admitted, 11 (50%) were discharged home, 4 (18%) remain hospitalized at the end of the study, and 7 (32%) died during hospitalization. Conclusions and Relevance: In this single-center case series, COVID-19 infection was associated with a case fatality rate of 25% in recipients of HT. Immunosuppression was reduced in most of this group of patients. Further study is required to evaluate the optimal approach to management of COVID-19 infection in the HT population.

Effect of Socioeconomic Status on Patients Supported with Contemporary Left Ventricular Assist Devices.

Continuous-flow left ventricular assist devices (CF-LVADs) are increasingly used in advanced heart failure patients. Recent studies suggest that low socioeconomic status (SES) predicts worst survival after heart transplantation. Both individual-level and neighborhood-level SES (nSES) have been linked to cardiovascular health; however, the impact of SES in CF-LVAD patients remains unknown. We hypothesized that SES is a major determinant of CF-LVAD candidacy and postimplantation outcomes. A retrospective chart review was conducted on 362 patients between February 2009 and May 2016. Neighborhood-level SES was measured using the American Community Survey data and the Agency for Healthcare Research and Quality SES index score. Individual-level SES was self reported. Kaplan-Meier survival analysis and multivariable Cox proportional hazards regression determined survival statistics. Patients in the highest SES tertile were older (58 ± 13 vs. 53 ± 14; p < 0.001), less likely to be black or Hispanic (26% vs. 70%; p < 0.001), more likely to be married (87% vs. 65%; p < 0.001), more likely to have private insurance (50% vs. 39%; p < 0.001), and more likely to have employment (29% vs. 15%; p < 0.001) compared with patients in the lowest tertile. Low nSES was associated with a decreased risk of death (hazard ratio [HR], 0.580; 95% confidence interval [CI], 0.347-0.970; p = 0.038) in comparison to the high nSES. However, after adjusting for baseline clinical morbidities, the relationship was no longer present. When selecting patients for a LVAD, SES should not be thought of as an immutable risk factor. Carefully selected low-SES patients could be safely implanted with CF-LVAD with outcomes comparable to high-SES patients.