Impella 5.5 as a bridge to heart transplantation: Waitlist outcomes in the United States.

OBJECTIVES: The 2018 United Network for Organ Sharing allocation policy change has led to a significant increase in the use of mechanical circulatory support devices in patients listed for orthotopic heart transplantation. However, there has been a paucity of data regarding the newest generation Impella 5.5, which received FDA approval in 2019. METHODS: The United Network for Organ Sharing registry was queried for all adults awaiting orthotopic heart transplantation who received Impella 5.5 support during their listing period. Waitlist, device, and early post-transplant outcomes were assessed. RESULTS: A total of 464 patients received Impella 5.5 support during their listing period with a median waitlist time of 19 days. Among them, 402 (87%) patients were ultimately transplanted, with 378 (81%) being directly bridged to transplant with the device. Waitlist death (7%) and clinical deterioration (5%) were the most common reasons for waitlist removal. Device complications and failure were uncommon (<5%). The most common post-transplant complication was acute kidney injury requiring dialysis (16%). Survival at 1-year post-transplant survival was 89.5%. CONCLUSION: Since its approval, the Impella 5.5 has been increasingly used as a bridge to transplant. This analysis demonstrates robust waitlist and post-transplant outcomes with minimal device-related and postoperative complications.

Subacute groin complications related to ECMO cannulation are associated with longer hospitalizations.

Subacute groin complications associated with extracorporeal membrane oxygenation (ECMO) cannulation are well recognized, yet their effects on clinical outcomes remain unknown. This single-center, retrospective study reviewed all patients receiving venoarterial ECMO from 01/2017 to 02/2020. Cohorts analyzed included transplanted patients (TPs) and non-transplanted patients (N-TPs) who did or did not develop ECMO-related subacute groin complications. Standard descriptive statistics were used for comparisons. Logistic regressions identified associated risk factors. Overall, 82/367 (22.3%) ECMO patients developed subacute groin complications, including 25/82 (30.5%) seromas/lymphoceles, 32/82 (39.0%) hematomas, 18/82 (22.0%) infections, and 7/82 (8.5%) non-specified collections. Of these, 20/82 (24.4%) underwent surgical interventions, most of which were muscle flaps (14/20, 70.0%). TPs had a higher incidence of subacute groin complications than N-TPs (14/28, 50.0% vs. 68/339, 20.1%, P = 0.001). Seromas/lymphoceles more often developed in TPs than N-TPs (10/14, 71.4% vs. 15/68, 22.1%, P = 0.001). Most patients with subacute groin complications survived to discharge (60/68, 88.2%). N-TPs who developed subacute groin complications had longer post-ECMO lengths of stay than those who did not (34 days, IQR 16-53 days vs. 17 days, IQR 8-34 days, P < 0.001). Post-ECMO length of stay was also longer among patients who underwent related surgical interventions compared to those who did not (50 days, IQR 35-67 days vs. 29 days, IQR 16-49 days, P = 0.007). Transplantation was the strongest risk factor for developing subacute groin complications (OR 3.91, CI95% 1.52-10.04, P = 0.005). Subacute groin complications and related surgical interventions are common after ECMO cannulation and are associated with longer hospital stays. When surgical management is warranted, muscle flaps may reduce lengths of stay compared to other surgical interventions.

HCV-Positive Allograft Use in Heart Transplantation Is Associated With Increased Access to Overdose Donors and Reduced Waitlist Mortality Without Compromising Outcomes.

BACKGROUND: Because of ongoing shortages of donors for heart transplantation, the use of donor candidates whose availabilities are the result of drug overdoses (ODs) has become increasingly prevalent, even though these donors carry a high preponderance of the now curable hepatitis C virus (HCV). This study investigated temporal trends and regional variabilities in HVC-positive (HCV+) allograft use in heart transplantation and assessed the relationship between the use of HCV+ graft donors and the use of OD donors as well as assessing waitlist and post-transplant outcomes. METHODS AND RESULTS: A retrospective review of the United Network for Organ Sharing database assessed adults listed for heart transplantation. Patients were stratified both temporally into pre-HCV and HCV eras related to HCV+ graft use trends and regionally by degree of HCV+ allograft use. Regions of high HCV+ donor use were associated with an increase in OD donor access by 7.8% across eras compared to 0.4% in low HCV+ donor-use regions. One-year waitlist mortality decreased from 4.7% to 2.5% across eras in high HCV+ donor-use regions (P= 0.001) and remained roughly the same as before in low HCV+ donor-use regions (3.0% vs 2.4%; P= 0.244.). Post-transplant survival at 1 year remained similar across eras. CONCLUSIONS: HCV+ donor allograft use can help to optimize donor use, decreasing waitlist mortality without compromising early survival. Ongoing assessment is essential to ensure long-term safety and efficacy of using HCV+ donors.

How Should ECMO Be Used Under Conditions of Severe Scarcity? A Population Study of Public Perception.

OBJECTIVE: To assess societal preferences regarding allocation of extracorporeal membrane oxygenation (ECMO) as a rescue option for select patients with coronavirus disease 2019 (COVID-19). DESIGN: Cross-sectional survey of a nationally representative sample. SETTING: Amazon Mechanical Turk platform. PARTICIPANTS: In total, responses from 1,041 members of Amazon Mechanical Turk crowd-sourcing platform were included. Participants were 37.9 ± 12.6 years old, generally white (65%), and college-educated (66.1%). Many reported working in a healthcare setting (22.5%) and having a friend or family member who was admitted to the hospital (43.8%) or died from COVID-19 (29.9%). MEASUREMENTS AND MAIN RESULTS: Although most reported an unwillingness to stay on ECMO for >one week without signs of recovery, participants were highly supportive of ECMO utilization as a life-preserving technique on a policy level. The majority (96.7%) advocated for continued use of ECMO to treat COVID patients during periods of resource scarcity but would prioritize those with highest likelihood of recovery (50%) followed by those who were sickest regardless of survival chances (31.7%). Patients >40 years old were more likely to prefer distributing ECMO on a first-come first-served basis (21.5% v 13.3%, p < 0.05). CONCLUSION: Even though participants expressed hesitation regarding ECMO in personal circumstances, they were uniformly in support of using ECMO to treat COVID patients at a policy level for others who might need it, even in the setting of severe scarcity.

Lack of volume-outcome association in ECMO bridge to heart transplantation.

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used as a bridge to cardiac transplantation. As the 2018 United Network for Organ Sharing (UNOS) heart allocation policy change elevated waitlist status for patients receiving mechanical circulatory support (MCS), we aimed to determine if a center's annual heart transplant volume was associated with ECMO-support duration and posttransplant outcomes. METHODS: Adults heart transplant candidates between January 1, 2011, and December 31, 2021, were isolated in the UNOS database. VA-ECMO use was identified at the time of listing for transplant. Average annual transplant volume was calculated by the center, with stratification as high (≥20 cardiac transplants, high volume center [HVC]) or low (<20 cardiac transplants, low volume center [LVC]) volume centers. Results are reported as mean (interquartile range) or n (%). RESULTS: In total, 543 patients at HVCs and 275 at LVCs were listed for transplant supported with VA-ECMO. Those listed at HVCs were more likely to be supported by intra-aortic balloon pump (103 [19%] vs. 32 [11.6%], p = .008) and inotropes (267 [49.2%] vs. 106 [38.5%], p = .004) at time of listing. Patients at HVCs received ECMO support for 6 [4-9] days, compared to 8 [4-15] days at low-volume centers (p = .030), and but were cannulated a similar time before listing (2 [1-5] vs. 3 [1-7] days, p = .517). There were no differences in rates of transplant (p = .2126), waitlist mortality (p = .8645), delisting due to clinical deterioration (p = .8419), or recovery (p = .1773) between groups. Among transplanted patients, there were no differences in support duration (6 [4-8] vs. 6 [4-10], p = .187), or time from registration to transplant (5 [2-20] vs. 7 [3-22] days, p = .560). Posttransplant survival did not vary (p = .293). CONCLUSIONS: LVCs can successfully bridge patients to transplant with VA-ECMO and achieve comparable outcomes to HVCs.

COVID-19 and cardiothoracic surgery: Effects on training and workforce utilization in a global pandemic.

BACKGROUND: The COVID-19 pandemic has disrupted all aspects of healthcare, including cardiothoracic surgery (CTS). We sought to determine the pandemic's impact on CTS trainees' educational experiences. METHODS: A survey was developed and distributed to members of the Thoracic Surgery Residents Association and other international CTS trainees. Trainees were asked to evaluate their cumulative experiences and share their overall perceptions of how CTS training had been impacted during the earliest months of the COVID-19 pandemic (i.e., since March 01, 2020). Surveys were distributed and responses were recorded June 25-August 05, 2020. In total, 748 surveys were distributed and 166 responses were received (overall response rate 22.2%). Of these, 126 of 166 responses (75.9%) met inclusion criteria for final analysis. RESULTS: Final responses analyzed included 45 of 126 (35.7%) United States (US) and 81 of 126 (64.3%) international trainees, including 101 of 126 (80.2%) senior and 25 of 126 (19.8%) junior trainees. Most respondents (76/126, 43.2%) lost over 1 week in the hospital due to the pandemic. Juniors (12/25, 48.0%) were more likely than seniors (20/101, 19.8%) to be reassigned to COVID-19-specific units (p < .01). Half of trainees (63/126) reported their case volumes were reduced by over 50%. US trainees (42/45, 93.3%) were more likely than international trainees (58/81, 71.6%) to report reduced operative case volumes (p < .01). Most trainees (104/126, 83%) believed their overall clinical acumen was not adversely impacted by the pandemic. CONCLUSIONS: CTS trainees in the United States and abroad have been significantly impacted by the COVID-19 pandemic, with time lost in the hospital, decreased operative experiences, less time on CTS services, and frequent reassignment to COVID-19-specific care settings.

Therapeutic Efficacy of Cryopreserved, Allogeneic Extracellular Vesicles for Treatment of Acute Myocardial Infarction.

Extracellular vesicles (EV) that are derived from endothelial progenitor cells (EPC) have been determined to be a novel therapy for acute myocardial infarction, with a promise for immediate "off-the-shelf" delivery. Early experience suggests delivery of EVs from allogeneic sources is safe. Yet, clinical translation of this therapy requires assurances of both EV stability following cryopreservation and absence of an adverse immunologic response to EVs from allogeneic donors. Thus, more bioactivity studies on allogeneic EVs after cold storage are necessary to establish quality standards for its widespread clinical use. Thus, in this study, we aimed to demonstrate the safety and efficacy in delivering cryopreserved EVs in allogeneic recipients as a therapy for acute myocardial infarction.In this present study, we have analyzed the cardioprotective effects of allogeneic EPC-derived EVs after storage at -80°C for 2 months, using a shear-thinning gel (STG) as an in vivo delivery vehicle. EV size, proteome, and nucleic acid cargo were observed to remain steady through extended cryopreservation via nanoparticle tracking analysis, mass spectrometry, and nanodrop analysis, respectively. Fresh and previously frozen EVs in STG were delivered intramyocardially in a rat model of myocardial infarction (MI), with both showing improvements in contractility, angiogenesis, and scar thickness in comparison to phosphate-buffered saline (PBS) and STG controls at 4 weeks post-MI. Pathologic analyses and flow cytometry revealed minimal inflammatory and immune upregulation upon exposure of tissue to EVs pooled from allogeneic donor cells.Allogeneic EPC-EVs have been known to elicit minimal immune activity and retain therapeutic efficacy after at least 2 months of cryopreservation in a post-MI model.

Organ allocation and procurement in cardiac transplantation.

PURPOSE OF REVIEW: There is a critical shortage of organs in cardiac transplantation. Recent advancements in both organ allocation and donor utilization have intended to address this shortage and optimally allocate allografts. This review evaluates several important aspects of recipient and donor management. For recipients, the focus is placed on the evolving mechanical circulatory support population and its bidirectional impact on organ allocation. From the donor standpoint, organ utilization is assessed with respect to increasing access to previously unused allografts. RECENT FINDINGS: Implementation of the new heart allocation system in the United States has better stratified waitlist candidates by illness acuity. Compared to the prior system, those requiring venoarterial extracorporeal membrane oxygenation support are less likely to die on the waitlist, although conflicting data exists whether this has improved their posttransplant survival. The use of pretransplant intra-aortic balloon pumps has markedly increased, whereas transplantation of patients with dischargeable left ventricular assist devices has decreased. Although some studies have reported inferior short- to mid-term posttransplant survival in the new system compared to its predecessor, others report similar outcomes.Several recent advancements in donor utilization have also been noted. Coinciding with the global increase in drug overdose deaths, efforts have been made to increase use of these donors who are frequently considered 'increased risk' and are hepatitis C-positive. Grafts from these donors appear safe to use. These, alongside donation after circulatory death donors, represent potentially underutilized populations that may effectively expand the donor pool. SUMMARY: Recent changes in organ allocation, alongside efforts to expand the donor pool, have attempted to improve cardiac allograft utilization and reduce the imbalance between organ supply and demand. Ongoing monitoring and continuous re-evaluation of these efforts will help guide future practice.

Redo mitral valve surgery following prior mitral valve repair.

BACKGROUND: The optimal treatment strategy following a failed mitral valve repair remains unclear. This study evaluated early and long-term outcomes of redo mitral valve repair (MVr) and replacement (MVR) after prior mitral valve repair. METHODS: Patients undergoing redo mitral valve surgery after prior mitral valve repair at a single institution between 2002 and 2014 were reviewed. Primary outcomes included operative mortality (30-day or in-hospital mortality) and long-term freedom from mitral valve reoperation and death. Secondary outcomes included postoperative complications. RESULTS: 305 patients underwent redo MVr (n = 48) or MVR (n = 257) after prior mitral valve repair. Concomitant procedures included tricuspid valve repair or replacement (23%), aortic valve replacement (6%), and coronary artery bypass grafting (4%), with no differences between cohorts. 18% were performed via right mini-thoracotomy (24% MVr vs 18% MVR, P = 0.31). Unadjusted and risk-adjusted operative mortality were lower with MVr (0% vs 8%, P = 0.04). Rates of postoperative complications were similar except for blood product transfusion (35% MVr vs 59% MVR, P = 0.003) and prolonged mechanical ventilation (8% MVr vs 29% MVR, P = 0.003). Long-term freedom from mortality was comparable: 96% MVr versus 86% MVR at 1 year and 78% MVr versus 68% MVR at 5 years (P = 0.29). CONCLUSIONS: When technically feasible, mitral valve re-repair can be safely performed with outcomes comparable to MVR.

Robotic versus laparoscopic radical nephrectomy: comparative analysis and cost considerations.

INTRODUCTION: Robotic-assisted laparoscopic radical nephrectomy (RRN) is an increasing utilized alternative to laparoscopic radical nephrectomy (LRN); however, there is a little data on comparative effectiveness and cost of these procedures. We analyzed perioperative outcomes and hospital charge difference among patients undergoing laparoscopic radical nephrectomy (LRN) and robotic radical nephrectomy (RRN). MATERIALS AND METHODS: Our institutional renal mass registry was queried for patients who underwent either LRN or RRN from 2010 to 2014. Demographic, perioperative outcomes and hospital charge data were compared between surgical approaches. RESULTS: Overall, 319 minimally invasive radical nephrectomies were performed during the study period. Of these, 243 were LRN and 76 were RRN. Patient demographic and tumor characteristics were similar between groups. Among operative characteristics, operative time (136 min versus 139 min, p = 0.531), intraoperative complications (2.8% versus 2.0%, p = 0.650), and length of stay (2 days versus 2 days, p = 0.745) were similar for LRN and RRN, respectively. Estimated blood loss (50 mL versus 100 mL, p = 0.041) and rate of conversion to an alternative surgical approach (1.0% versus 11.1%, p < 0.001) were higher in RRN. RRN cases were also more likely to include lymph node dissection (12.6% versus 24.2%, p = 0.031). Total charges trended higher for RRN but did not meet traditional levels of significance ($14,913 versus $16,265, p = 0.171). CONCLUSIONS: RRN appears to be a clinically equivalent alternative to LRN with similar perioperative outcomes, albeit at greater hospital charges.

Mapping the BH3 Binding Interface of Bcl-xL, Bcl-2, and Mcl-1 Using Split-Luciferase Reassembly.

The recognition of helical BH3 domains by Bcl-2 homology (BH) receptors plays a central role in apoptosis. The residues that determine specificity or promiscuity in this interactome are difficult to predict from structural and computational data. Using a cell free split-luciferase system, we have generated a 276 pairwise interaction map for 12 alanine mutations at the binding interface for three receptors, Bcl-xL, Bcl-2, and Mcl-1, and interrogated them against BH3 helices derived from Bad, Bak, Bid, Bik, Bim, Bmf, Hrk, and Puma. This panel, in conjunction with previous structural and functional studies, starts to provide a more comprehensive portrait of this interactome, explains promiscuity, and uncovers surprising details; for example, the Bcl-xL R139A mutation disrupts binding to all helices but the Bad-BH3 peptide, and Mcl-1 binding is particularly perturbed by only four mutations of the 12 tested (V220A, N260A, R263A, and F319A), while Bcl-xL and Bcl-2 have a more diverse set of important residues depending on the bound helix.

Outcomes and quality of life in patients receiving mitral surgery for asymptomatic disease.

Objectives: We sought to characterize the demographics, outcomes, and quality of life of asymptomatic patients undergoing mitral valve surgery at our center over a 10-year period. Methods: Adults undergoing mitral surgery were retrospectively reviewed between 2010 and 2019. Patients were included if deemed asymptomatic by review of referring cardiologist and surgeon consultation. Patients were administered a telephone survey consisting of the Kansas City Cardiomyopathy Questionnaire as well as free-response regarding satisfaction surrounding their operation. Outcomes included survival, Kansas City Cardiomyopathy Questionnaire metrics, and thematic analysis of free response questions. Results: A total of 145 patients were identified who were deemed asymptomatic. Their average age was 60.3 ± 12.1 years, and 71% were male. No patients had endocarditis, and 34% had decreased ejection fraction (<60%). Repair was achieved in 95% of patients. Median length of stay was 6 (5-8) days. Ten-year survival was 91%, with no differences noted by ejection fraction. Composite Kansas City Cardiomyopathy Questionnaire score was 100 (96-100). The lowest component score was "Quality of Life," with 22% of patients reporting being "mostly satisfied" with present cardiac status. Most common themes expressed were gratitude with surgery results (58%), satisfaction with being able to stay active (23%), and happiness with early disease treatment (21%). Only 1 patient (0.7%) expressed regret with surgery choice. Conclusions: Mitral surgery for asymptomatic disease can be performed with good long-term outcomes in select patients, and the majority experience excellent quality of life and satisfaction with current health. Continued assessments of quality of life are important in evaluating outcomes of mitral surgery as indications grow.

Heart Retransplantation Under the 2018 Adult Heart Allocation Policy.

BACKGROUND: The purpose of the present study was to characterize the impact of the 2018 adult heart allocation policy change on waiting list and posttransplant outcomes of heart retransplantation in the United States. METHODS: All adults listed for heart retransplantation from May 2015 to June 2022 were identified using the United Network for Organ Sharing database. Patients were stratified into eras (era 1 and era 2) based on the heart allocation change on October 18, 2018. Competing risks regressions and Cox proportional hazards models were used to assess differences across eras in waiting list outcomes and 1-year posttransplant survival, respectively. RESULTS: The analysis included 356 repeat heart transplant recipients, with 207 (58%) receiving retransplantation during era 2. Patients who received a retransplant in era 2 were more commonly bridged with extracorporeal membrane oxygenation (21% vs 8%, P < .01) and intra-aortic balloon pump (29% vs 13%, P < .001) and had a lower likelihood of death/deterioration on the waiting list (subdistribution hazard ratio, 0.52; 95% CI, 0.33-0.82) compared with those in era 1. Rates of 30-day mortality (7% vs 7%, P = .99) and 1-year survival (82% vs 87%, P = .27) were not significantly different among retransplantation recipients across eras. After adjustment, retransplantation in era 2 was not associated with an increased hazard of mortality (adjusted hazard ratio, 1.13; 95% CI, 0.55-2.30). The gap in 1-year mortality between primary transplant and retransplant recipients increased from era 1 to 2. CONCLUSIONS: Heart retransplantation candidates have experienced improved waiting list outcomes after the 2018 adult heart allocation policy, without significant changes to posttransplant survival.

Non-inferior outcomes in lower urgency patients transplanted with extended criteria donor hearts.

BACKGROUND: Recent work has suggested that outcomes among heart transplant patients listed at the lower-urgency (United Network for Organ Sharing Status 4 or 6) status may not be significantly impacted by donor comorbidities. The purpose of this study was to investigate outcomes of extended criteria donors (ECD) in lower versus higher urgency patients undergoing heart transplantation. METHODS: The United Network for Organ Sharing (UNOS) database was queried for all adult patients undergoing heart transplantation from October 18, 2018 through December 31, 2021. Patients were stratified by degree of urgency (higher urgency: UNOS 1 or 2 vs lower urgency: UNOS 4 or 6) and receipt of ECD hearts, as defined by donor hearts failing to meet established acceptable use criteria. Outcomes were compared using propensity score matched cohorts. RESULTS: Among 9,160 patients included, 2,320 (25.4%) were low urgency. ECD hearts were used in 35.5% of higher urgency (HU) patients and 39.2% of lower urgency (LU) patients. While ECD hearts had an impact on survival among high-urgency patients (p < 0.01), there was no difference in 1- and 2-year survival (p > 0.05) found among low urgency patients receiving ECD versus standard hearts. Neither ECDs nor individual ECD criteria were independently associated with mortality in low urgency patients (p > 0.05). CONCLUSIONS: Post-transplant outcomes among low urgency patients are not adversely affected by receipt of ECD vs. standard hearts. Expanding the available donor pool by optimizing use of ECDs in this population may increase transplant frequency, decrease waitlist morbidity, and improve postoperative outcomes for the transplant community at large.

Decreased survival of simultaneous heart-kidney transplant recipients in the new heart allocation era.

BACKGROUND: In 2018, the United Network for Organ Sharing (UNOS) modified their heart allocation policy to reduce waitlist mortality. The rates of simultaneous heart-kidney transplant (SHKT) have dramatically increased in recent years, despite increased rates of posttransplant renal failure in the new policy era. This study sought to investigate the impact of the new allocation system on waitlist and posttransplant outcomes of simultaneous heart-kidney transplantation. METHODS: Adult patients listed for SHKT between 2012 and 2021 were included. Patients were cross-validated across both Thoracic and Kidney UNOS databases to confirm accurate listing and transplant data. Patients were stratified according to listing era. The Fine and Gray model was used to assess waitlist outcomes and posttransplant renal graft function. Kaplan-Meier analysis and Cox regression were used to compare posttransplant survival. RESULTS: A total of 2,588 patients were included, of whom 1,406 (54.1%) were listed between 2012 and 2018 (era 1) and 1,182 (45.9%) between 2019 and 2021 (era 2). Era 2 was associated with increased likelihood of transplant (adjusted Sub-hazard ratios (aSHR): 1.52; p < 0.01) and decreased waitlist mortality (aSHR: 0.63; p < 0.01). Posttransplant survival at 2 years was decreased in era 2 (78.8% vs 86.9%; p < 0.01). Undersized hearts (hazard ratio [HR]: 2.02; p < 0.01), use of extracorporeal membrane oxygenation (HR: 2.67; p < 0.1), and transplants performed following the policy change (HR: 1.45; p = 0.03) were associated with increased mortality. Actuarial survival (combined waitlist and posttransplant) was significantly lower in the modern era (71.6% vs 62.2%; p = 0.02). CONCLUSIONS: The allocation policy change has improved waitlist outcomes in patients listed for SHKT but potentially at the cost of worsened posttransplant outcomes.

Outcomes of COVID-19-Positive Donor Heart Transplantation in the United States.

Background Little is known regarding the impact of donor COVID-19 status on recipient outcomes after heart transplantation. In this study, we characterize outcomes of the first 110 heart transplants from organ donors positive for COVID-19 (COVID-19+) in the United States. Methods and Results Retrospective analysis of the United Network for Organ Sharing database was performed for single-organ adult heart transplants from January 2020 to March 2022. Donor COVID-19+ status was defined as a positive nucleic acid amplification, antigen, or other COVID-19 test within 7 days of transplant. Nearest-neighbor propensity score matching used to adjust for differences between recipients of COVID-19+ and nonpositive donor hearts. Overall, 7251 heart transplants were included in analysis, with 110 using COVID-19+ donor hearts. Recipients of COVID-19+ allografts were younger (54 [interquartile range, 41-61]) versus 57 [46-64] years; P=0.02) but had similar rates of female sex and non-White race compared with those receiving allografts from negative donors. Nearest-neighbor propensity score matching resulted in 100 well-matched pairs of recipients of COVID-19+ versus nonpositive donor organs. The 2 matched groups had similar median lengths of stay (15 [11-23] days versus 15 [13-23] days; P=0.40), rates of graft failure (1% versus 0%; P=0.99), 30-day death (3% versus 3%; P=0.99), and 3-month survival (88% versus 94%; P=0.23) compared with recipients of nonpositive donors. No deaths occurred due to COVID-19 infection among the 8 (7%) total deceased recipients of COVID-19+ allografts to date. Conclusions Short-term outcomes of heart transplant recipients receiving COVID-19+ donor organs are reassuring. However, continued monitoring for long-term survival and potential complications are warranted.

Neighborhood Socioeconomic Status Independently Predicts Outcomes After Mitral Valve Surgery.

BACKGROUND: Socioeconomic status has increasingly recognized influence on outcomes after cardiac surgery. However, singular metrics fail to fully capture the socioeconomic context within which patients live, which vary greatly between neighborhoods. We sought to explore the impact of neighborhood-level socioeconomic status on patients undergoing mitral valve surgery in the United States. METHODS: Adults undergoing first-time, isolated mitral valve surgery were queried from The Society of Thoracic Surgeons Adult Cardiac Surgery Database between 2012 and 2018. Socioeconomic status was quantified using the Area Deprivation Index, a weighted composite including average housing prices, household incomes, education, and employment levels. The associations between regional deprivation, access to mitral surgery, valve repair rates, and outcomes were evaluated using logistic regression. RESULTS: Among 137,100 patients included, patients with socioeconomic deprivation had fewer elective presentations, more comorbidity burden, and more urgent/emergent surgery. Patients from less disadvantaged areas received operations from higher volume surgeons and had higher repair rates (highest vs lowest quintile: 72% vs 51%, P < .001, more minimally-invasive approach (33% vs 20%, P < .001), lower composite complication rate (42% vs 50%, P < .001), and lower 30-day mortality (1.8% vs 3.9%, P < .001). After hierarchical multivariable adjustment, the Area Deprivation Index significantly predicted 30-day mortality and repair rate (P < .001). CONCLUSIONS: In a risk-adjusted national analysis of mitral surgery, patients from more deprived areas were less likely to undergo mitral repair and more likely to have complications. Further work at targeting neighborhood-level disparity is important to improving mitral surgical outcomes in the United States.

Higher Rates of Dialysis and Subsequent Mortality in the New Allocation Era for Heart Transplants.

BACKGROUND: In 2018, a United Network for Organ Sharing (UNOS) policy change increased prioritization of patients bridged with temporary mechanical circulatory support devices, such as venoarterial ECMO, for cardiac transplantation. Considering increased waitlist acuity, we sought to characterize whether this was associated with an increased risk for development of postoperative acute renal failure requiring dialysis (AKI-D) and risk of death after transplantation. METHODS: Dialysis-naive adults receiving single-organ heart transplant between November 2009 and February 2020 were stratified by receipt of AKI-D. Era 1 and era 2 were defined by the periods of UNOS allocation before and after policy change, respectively. Multivariable logistic regression was performed to determine risk factors for AKI-D. Rates of AKI-D were compared by propensity score-matched cohorts. Survival was compared by Kaplan-Meier analysis. RESULTS: A total of 20 698 patients were included. Venoarterial ECMO use significantly increased in era 2 (5.6% vs 0.58%; P < .01). Overall prevalence of AKI-D was greater in era 2 (13.5% vs 10.2%; P < .01). Use of preoperative ECMO, intra-aortic balloon pump, and ventilators and longer ischemia times were identified as independent risk factors for development of AKI-D. Five- and 10-year survival rates were significantly decreased for patients with AKI-D. There was no short-term survival difference of patients with AKI-D between era 2 and the more contemporary era 1. CONCLUSIONS: Patients in whom AKI-D develops after transplantation have significantly worse short- and long-term outcomes. Preoperative use of ECMO, preoperative ventilator support, and longer ischemia times are risk factors for development of AKI-D, and their prevalence has increased since the allocation policy change.

Waitlist Trends in Heart-Liver Transplantation With Updated US Heart Allocation System.

BACKGROUND: In October 2018, the United States implemented a change in the donor heart allocation policy from a three-tiered to a six-tiered status system. The purpose of the current study was to examine changes in waitlist patterns among patients listed for concomitant heart-liver transplantation with implementation of the new allocation system. METHODS: Patients listed for heart-liver transplantation between January 1, 2012, and June 30, 2021, were identified from the United Network for Organ Sharing database. Patients were grouped by era according to initial list date before or after October 18, 2018. Competing risks regression for mortality, transplantation, removal from waitlist due to illness was performed according to the method of Fine and Gray. Waitlist data were censored at 3 years from initial listing. RESULTS: Overall, 523 patients were identified, of whom 310 were listed before (era 1, 59%) and 213 after (era 2, 41%) allocation change. Patients in era 1 were older, had more restrictive cardiomyopathy, and more preoperative inotrope use (all P < .05). However, patients in era 2 has longer ischemic times (3.5 ± 1.1 vs 3.1 ± 1.1 hours, P < .01) and more intraaortic balloon pump use (8.9% vs 3.9%, P = .016). Era 2 was associated with lower subdistribution hazard for death (hazard ratio 0.37; 95% CI, 0.13-1.02; P = .054) and increased transplantation (hazard ratio 1.35; 95% CI, 1.06-1.72; P = .015). CONCLUSIONS: The implementation of the US donor heart allocation policy was associated with more preoperative intraaortic balloon pump use for patients listed for heart-liver transplantation. Despite that, the modern era was associated with lower waitlist mortality and more frequent transplantation, without increased risk of delisting due to illness.

Prosthesis Choice in Dialysis Patients Undergoing Mitral Valve Replacement.

BACKGROUND: Patients with renal disease on dialysis have significant comorbidity limiting life expectancy; however, these patients may experience accelerated prosthetic valve degeneration. The purpose of this study was to examine the impact of prosthesis choice on outcomes in dialysis patients undergoing mitral valve replacement (MVR) at our high-volume academic center. METHODS: Adults undergoing MVR were retrospectively reviewed between January 2002 and November 2019. Patients were included if they had documented renal failure and dialysis requirements before presentation. Patients were stratified by mechanical vs bioprosthetic prosthesis. Death and recurrent severe valve failure (3+ or greater) or redo mitral operation were used as primary outcomes. RESULTS: There were 177 dialysis patients identified who underwent MVR. Of these, 118 (66.7%) received bioprosthetic valves, whereas 59 (33.3%) received mechanical valves. Those who received mechanical valves were younger (48 vs 61 years; P < .001) and had less diabetes (32% vs 51%; P = .019). Prevalence of endocarditis and atrial fibrillation was similar. Postoperative length of stay was not different between groups. Risk-adjusted hazard for 5-year mortality was similar between groups (P = .668). Early mortality was high, with both groups having <50% actuarial survival at 2 years. No differences were noted in rates of structural valve deterioration or reintervention. More stroke events were noted on follow-up in patients receiving mechanical valves (15% vs 6%; P = .041). Endocarditis was the leading reason for reintervention; 4 patients received repeated surgery for bioprosthetic valve failure. CONCLUSIONS: MVR in dialysis patients carries significant morbidity and increased midterm mortality. Decreased life expectancy should be considered in the tailoring of prosthesis choice to dialysis-dependent patients.