Outcomes of Patients Transferred to Tertiary Care Centers for Treatment of Cardiogenic Shock: A Cardiogenic Shock Working Group Analysis.

BACKGROUND: Consensus recommendations for cardiogenic shock (CS) advise transfer of patients in need of advanced options beyond the capability of "spoke" centers to tertiary/"hub" centers with higher capabilities. However, outcomes associated with such transfers are largely unknown beyond those reported in individual health networks. OBJECTIVES: To analyze a contemporary, multicenter CS cohort with the aim of comparing characteristics and outcomes of patients between transfer (between spoke and hub centers) and nontransfer cohorts (those primarily admitted to a hub center) for both acute myocardial infarction (AMI-CS) and heart failure-related HF-CS. We also aim to identify clinical characteristics of the transfer cohort that are associated with in-hospital mortality. METHODS: The Cardiogenic Shock Working Group (CSWG) registry is a national, multicenter, prospective registry including high-volume (mostly hub) CS centers. Fifteen U.S. sites contributed data for this analysis from 2016-2020. RESULTS: Of 1890 consecutive CS patients enrolled into the CSWG registry, 1028 (54.4%) patients were transferred. Of these patients, 528 (58.1%) had heart failure-related CS (HF-CS), and 381 (41.9%) had CS related to acute myocardial infarction (AMI-CS). Upon arrival to the CSWG site, transfer patients were more likely to be in SCAI stages C and D, when compared to nontransfer patients. Transfer patients had higher mortality rates (37% vs 29%, < 0.001) than nontransfer patients; the differences were driven primarily by the HF-CS cohort. Logistic regression identified increasing age, mechanical ventilation, renal replacement therapy, and higher number of vasoactive drugs prior to or within 24 hours after CSWG site transfer as independent predictors of mortality among HF-CS patients. Conversely, pulmonary artery catheter use prior to transfer or within 24 hours of arrival was associated with decreased mortality rates. Among transfer AMI-CS patients, BMI > 28 kg/m2, worsening renal failure, lactate > 3 mg/dL, and increasing numbers of vasoactive drugs were associated with increased mortality rates. CONCLUSION: More than half of patients with CS managed at high-volume CS centers were transferred from another hospital. Although transfer patients had higher mortality rates than those who were admitted primarily to hub centers, the outcomes and their predictors varied significantly when classified by HF-CS vs AMI-CS.

Evolving Trends and Impact of Waitlist Transfusion on Recipient Outcomes Following Heart Transplantation.

BACKGROUND: This study evaluates the clinical trends, risk factors, and impact of waitlist blood transfusion on outcomes following isolated heart transplantation. METHODS: The UNOS registry was queried to identify adult recipients from January 1, 2014, to June 30, 2022. The recipients were stratified into two groups depending on whether they received a blood transfusion while on the waitlist. The incidence of waitlist transfusion was compared before and after the 2018 allocation policy change. The primary outcome was survival. Propensity score-matching was performed. Multivariable logistic regression was performed to identify predictors of waitlist transfusion. A sub-analysis was performed to evaluate the impact of waitlist time on waitlist transfusion. RESULTS: From the 21 926 recipients analyzed in this study, 4201 (19.2%) received waitlist transfusion. The incidence of waitlist transfusion was lower following the allocation policy change (14.3% vs. 23.7%, p < 0.001). The recipients with waitlist transfusion had significantly reduced 1-year posttransplant survival (88.8% vs. 91.9%, p < 0.001) compared to the recipients without waitlist transfusion in an unmatched comparison. However, in a propensity score-matched comparison, the two groups had similar 1-year survival (90.0% vs. 90.4%, p = 0.656). Multivariable analysis identified ECMO, Impella, and pretransplant dialysis as strong predictors of waitlist transfusion. In a sub-analysis, the odds of waitlist transfusion increased nonlinearly with longer waitlist time. CONCLUSION: There is a lower incidence of waitlist transfusion among transplant recipients under the 2018 allocation system. Waitlist transfusion is not an independent predictor of adverse posttransplant outcomes but rather a marker of the patient's clinical condition. ECMO, Impella, and pretransplant dialysis are strong predictors of waitlist transfusion.

Clinical Outcomes Associated With Diltiazem Use in Heart Failure With Reduced Ejection Fraction After Implementation of a Clinical Support System.

BACKGROUND: Despite atrial fibrillation guideline recommendations, many patients with heart failure with reduced ejection fraction (EF) continue to receive IV diltiazem for acute rate control. OBJECTIVE: Our institution recently implemented a clinical decision support system (CDSS)-based tool that recommends against the use of diltiazem in patients with an EF ≤ 40%. The objective of this study was to evaluate outcomes of adherence to the aforementioned CDSS-based tool. METHODS: This multi-hospital, retrospective study assessed patients who triggered the CDSS alert and compared those who did and did not discontinue diltiazem. The primary outcome was the occurrence of clinical deterioration. The primary endpoint was compared utilizing a Fisher's Exact Test, and a multivariate logistic regression model was developed to confirm the results of the primary analysis. RESULTS: A total of 246 patients were included in this study with 146 patients in the nonadherent group (received diltiazem) and 100 patients in the adherent group (did not receive diltiazem). There was a higher proportion of patients experiencing clinical deterioration in the alert nonadherence group (33% vs 21%, P = 0.044), including increased utilization of inotropes and vasopressors, and higher rate of transfer to ICU. CONCLUSION AND RELEVANCE: In patients with heart failure with reduced EF, diltiazem use after nonadherence to a CDSS alert resulted in an increased risk of clinical deterioration. This study highlights the need for improved provider adherence to diltiazem clinical decision support systems.

Outcomes of Impella 5.0 and 5.5 for cardiogenic shock: A single-center 137 patient experience.

BACKGROUND: This study evaluated the outcomes of patients with cardiogenic shock (CS) supported with Impella 5.0 or 5.5 and identified risk factors for in-hospital mortality. METHODS: Adults with CS who were supported with Impella 5.0 or 5.5 at a single institution were included. Patients were stratified into three groups according to their CS etiology: (1) acute myocardial infarction (AMI), (2) acute decompensated heart failure (ADHF), and (3) postcardiotomy (PC). The primary outcome was survival, and secondary outcomes included adverse events during Impella support and length of stay. Multivariable logistic regression was performed to identify risk factors for in-hospital mortality. RESULTS: One hundred and thirty-seven patients with CS secondary to AMI (n = 47), ADHF (n = 86), and PC (n = 4) were included. The ADHF group had the highest survival rates at all time points. Acute kidney injury (AKI) was the most common complication during Impella support in all 3 groups. Increased rates of AKI and de novo renal replacement therapy were observed in the PC group, and the AMI group experienced a higher incidence of bleeding requiring transfusion. Multivariable analysis demonstrated diabetes mellitus, elevated pre-insertion serum lactate, and elevated pre-insertion serum creatinine were independent predictors of in-hospital mortality, but the etiology of CS did not impact mortality. CONCLUSIONS: This study demonstrates that Impella 5.0 and 5.5 provide effective mechanical support for patients with CS with favorable outcomes, with nearly two-thirds of patients alive at 180 days. Diabetes, elevated pre-insertion serum lactate, and elevated pre-insertion serum creatinine are strong risk factors for in-hospital mortality.

Pulmonary Artery Catheter Use and Risk of In-hospital Death in Heart Failure Cardiogenic Shock.

BACKGROUND: Pulmonary artery catheters (PACs) are increasingly used to guide management decisions in cardiogenic shock (CS). The goal of this study was to determine if PAC use was associated with a lower risk of in-hospital mortality in CS owing to acute heart failure (HF-CS). METHODS AND RESULTS: This multicenter, retrospective, observational study included patients with CS hospitalized between 2019 and 2021 at 15 US hospitals participating in the Cardiogenic Shock Working Group registry. The primary end point was in-hospital mortality. Inverse probability of treatment-weighted logistic regression models were used to estimate odds ratios (ORs) and corresponding 95% confidence intervals (CI), accounting for multiple variables at admission. The association between the timing of PAC placement and in-hospital death was also analyzed. A total of 1055 patients with HF-CS were included, of whom 834 (79%) received a PAC during their hospitalization. In-hospital mortality risk for the cohort was 24.7% (n = 261). PAC use was associated with lower adjusted in-hospital mortality risk (22.2% vs 29.8%, OR 0.68, 95% CI 0.50-0.94). Similar associations were found across SCAI stages of shock, both at admission and at maximum SCAI stage during hospitalization. Early PAC use (≤6 hours of admission) was observed in 220 PAC recipients (26%) and associated with a lower adjusted risk of in-hospital mortality compared with delayed (≥48 hours) or no PAC use (17.3% vs 27.7%, OR 0.54, 95% CI 0.37-0.81). CONCLUSIONS: This observational study supports PAC use, because it was associated with decreased in-hospital mortality in HF-CS, especially if performed within 6 hours of hospital admission. CONDENSED ABSTRACT: An observational study from the Cardiogenic Shock Working Group registry of 1055 patients with HF-CS showed that pulmonary artery catheter (PAC) use was associated with a lower adjusted in-hospital mortality risk (22.2% vs 29.8%, odds ratio 0.68, 95% confidence interval 0.50-0.94) compared with outcomes in patients managed without PAC. Early PAC use (≤6 hours of admission) was associated with a lower adjusted risk of in-hospital mortality compared with delayed (≥48 hours) or no PAC use (17.3% vs 27.7%, odds ratio 0.54, 95% confidence interval 0.37-0.81).

Extracorporeal Membrane Oxygenation for Graft Dysfunction Early After Heart Transplantation: A Systematic Review and Meta-analysis.

INTRODUCTION: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a prevailing option for the management of severe early graft dysfunction. This systematic review and individual patient data (IPD) meta-analysis aims to evaluate (1) mortality, (2) rates of major complications, (3) prognostic factors, and (4) the effect of different VA-ECMO strategies on outcomes in adult heart transplant (HT) recipients supported with VA-ECMO. METHODS AND RESULTS: We conducted a systematic search and included studies of adults (≥18 years) who received VA-ECMO during their index hospitalization after HT and reported on mortality at any timepoint. We pooled data using random effects models. To identify prognostic factors, we analysed IPD using mixed effects logistic regression. We assessed the certainty in the evidence using the GRADE framework. We included 49 observational studies of 1477 patients who received VA-ECMO after HT, of which 15 studies provided IPD for 448 patients. There were no differences in mortality estimates between IPD and non-IPD studies. The short-term (30-day/in-hospital) mortality estimate was 33% (moderate certainty, 95% confidence interval [CI] 28%-39%) and 1-year mortality estimate 50% (moderate certainty, 95% CI 43%-57%). Recipient age (odds ratio 1.02, 95% CI 1.01-1.04) and prior sternotomy (OR 1.57, 95% CI 0.99-2.49) are associated with increased short-term mortality. There is low certainty evidence that early intraoperative cannulation and peripheral cannulation reduce the risk of short-term death. CONCLUSIONS: One-third of patients who receive VA-ECMO for early graft dysfunction do not survive 30 days or to hospital discharge, and one-half do not survive to 1 year after HT. Improving outcomes will require ongoing research focused on optimizing VA-ECMO strategies and care in the first year after HT.

Basiliximab induction versus no induction in adult heart transplantation.

BACKGROUND: Induction immunosuppression in heart transplant recipients varies greatly by center. Basiliximab (BAS) is the most commonly used induction immunosuppressant but has not been shown to reduce rejection or improve survival. The objective of this retrospective study was to compare rejection, infection, and mortality within the first 12 months following heart transplant in patients who received BAS or no induction. METHODS: This was a retrospective cohort study of adult heart transplant recipients given BAS or no induction from January 1, 2017 to May 31, 2021. The primary endpoint was incidence of treated acute cellular rejection (ACR) at 12-months post-transplant. Secondary endpoints included ACR at 90 days post-transplant, incidence of antibody-mediated rejection (AMR) at 90 days and 1 year, incidence of infection, and all-cause mortality at 1 year. RESULTS: A total of 108 patients received BAS, and 26 patients received no induction within the specified timeframe. There was a lower incidence of ACR within the first year in the BAS group compared to the no induction group (27.7 vs. 68.2%, p < .002). BAS was independently associated with a lower probability of having a rejection event during the first 12-months post-transplant (hazard ratio (HR) .285, 95% confidence interval [CI] .142-.571, p < .001). There was no difference in the rate of infection and in mortality after hospital discharge at 1-year post-transplant (6% vs. 0%, p = .20). CONCLUSION: BAS appears to be associated with greater freedom from rejection without an increase in infections. BAS may be a preferred to a no induction strategy in patients undergoing heart transplantation.

Reduction of HLA donor specific antibodies in heart transplant patients treated with proteasome inhibitors for antibody mediated rejection.

In this project, we describe proteasome inhibitor (PI) treatment of antibody-mediated rejection (AMR) in heart transplantation (HTX). From January 2018 to September 2021, 10 patients were treated with PI for AMR: carfilzomib (CFZ) n = 8; bortezomib (BTZ) n = 2. Patients received 1-3 cycles of PI. All patients had ≥1 strong donor-specific antibody (DSA) (mean fluorescence intensity [MFI] > 8000) in undiluted serum. Most DSAs (20/21) had HLA class II specificity. The MFI of strong DSAs had a median reduction of 56% (IQR = 13%-89%) in undiluted serum and 92% (IQR = 53%-95%) at 1:16 dilution. Seventeen DSAs in seven patients were reduced > 50% at 1:16 dilution after treatment. Four DSAs from three patients did not respond. DSA with MFI > 8000 at 1:16 dilution was less responsive to treatment. 60% (6/10) patients presented with graft dysfunction; 4/6 recovered ejection fraction > 40% after treatment. Pathologic AMR was resolved in 5/7 (71.4%) of patients within 1 year after treatment. 9/10 (90%) patients survived to 1 year after AMR diagnosis. Using PI in AMR resulted in significant DSA reduction with some resolution of graft dysfunction. Larger studies are needed to evaluate PI for AMR.

Long-Term outcomes in adult patients with congenital heart disease considered for transplantation: A single center study.

BACKGROUND: Adult congenital heart disease (ACHD) patients pose unique challenges in identifying the time for transplantation and factors influencing outcomes. OBJECTIVE: To identify hemodynamic, functional, and laboratory parameters that correlate with 1- and 10-year outcomes in ACHD patients considered for transplantation. METHODS: A retrospective chart review of long-term outcomes in adult patients with congenital heart disease (CHD) evaluated for heart or heart + additional organ transplant between 2004 and 2014 at our center was performed. A machine learning decision tree model was used to evaluate multiple clinical parameters correlating with 1- and 10-year survival. RESULTS: We identified 58 patients meeting criteria. D-transposition of the great arteries (D-TGA) with atrial switch operation (20.7%), tetralogy of Fallot/pulmonary atresia (15.5%), and tricuspid atresia (13.8%) were the most common diagnosis for transplant. Single ventricle patients were most likely to be listed for transplantation (39.8% of evaluated patients). Among a comprehensive list of clinical factors, invasive hemodynamic parameters (pulmonary capillary wedge pressure (PCWP), systemic vascular pressure (SVP), and end diastolic pressures (EDP) most correlated with 1- and 10-year outcomes. Transplanted patients with SVP < 14 and non- transplanted patients with PCWP < 15 had 100% survival 1-year post-transplantation. CONCLUSION: For the first time, our study identifies that hemodynamic parameters most strongly correlate with 1- and 10-year outcomes in ACHD patients considered for transplantation, using a data-driven machine learning model.

Evaluation of Newly Integrated Bivalirudin Titration Protocol in Patients With Mechanical Circulatory Support.

BACKGROUND: Patients with cardiogenic shock or end-stage heart failure can be maintained on mechanical circulatory support (MCS) devices. Once a patient undergoes placement of a device, obtaining and maintaining therapeutic anticoagulation is vital. Guidelines recommend the use of institutional protocols to assist in dosing and titration of anticoagulants. OBJECTIVE: The purpose of this study was to characterize the use of bivalirudin before and after the implementation of a standardized titration protocol in patients with MCS. METHODS: A retrospective review of patients who received bivalirudin for MCS (VA ECMO [veno-arterial extracorporeal membrane oxygenation], Impella, or LVAD [left ventricular assist device]) before and after the implementation of the titration protocol into the electronic health record (EHR) was conducted. The primary outcome was to compare the proportion of therapeutic activated partial thromboplastin time (aPTT). Secondary outcomes included number of subtherapeutic and supratherapeutic aPTTs, incidence of bleeding and clotting events, bivalirudin titrations per day, and percentage of patients with therapeutic aPTT level. RESULTS: A total of 100 patients were included (precohort = 67; postcohort = 33). The proportion of therapeutic aPTTs was significantly higher in the postcohort than that in the precohort (62% vs 48%; P < 0.001). The postcohort had 0% of patients failing to achieve therapeutic aPTT levels. The number of titrations per day was significantly lower in the postcohort, with 1.20 titrations per day versus 1.93 in the precohort (P < 0.001). CONCLUSIONS: Implementation of the bivalirudin titration nomograms within the EHR significantly increased the number of therapeutic aPTTs, reduced the number of patients who never achieved a therapeutic aPTT, and reduced the required number of titrations per day.

Outcomes of systemic bivalirudin and sodium bicarbonate purge solution for Impella 5.5.

BACKGROUND: Impella 5.5 (Abiomed; Danvers, MA) (IMP5) is a commonly used, surgically implanted, tMCS device that requires systemic anticoagulation and purge solution to avoid pump failure. To avoid heparin-induced thrombocytopenia (HIT) from unfractionated heparin (UFH) use, our program has explored the utility of bivalirudin (BIV) for systemic anticoagulation and sodium bicarbonate-dextrose purge solution (SBPS) in IMP5.5. METHODS: This single center, retrospective study included 34 patients supported on IMP5.5 with BIV based AC and SBPS between December 1st 2020 to December 1st 2021.The efficacy and safety end points were incidence of development of HIT, Tissue Plasminogen Activator (tPA) use for suspected pump thrombosis, stroke, and device failure as well as clinically significant bleeding. RESULTS: The median duration of IMP5.5 support was 9.8 days (IQR: 6-15). Most patients were bridged to HTX (58%) followed by recovery (27%) and LVAD implantation (15%). Patients were therapeutic on bivalirudin for 64% of their IMP5.5 support. One patient (2.9%) suffered from ischemic stroke and 26.5% (9) patients developed clinically significant bleeding. tPA was administered to 7(21%) patients. One patient in the entire cohort developed HIT. CONCLUSIONS: Our experience supports the use of systemic BIV and SBPS as a method to avoid heparin exposure in a patient population predisposed to the development of HIT.

Health-related quality of life and psychological indicators of thriving 15-19 years after heart or lung transplantation.

BACKGROUND: Survival into the second decade after cardiothoracic transplantation (CTX) is no longer uncommon. Few data exist on any health-related quality of life (HRQOL) impairments survivors face, or whether they may even experience positive psychological outcomes indicative of "thriving" (e.g., personal growth). We provide such data in a long-term survivor cohort. METHODS: Among 304 patients prospectively studied across the first 2 years post-CTX, we re-interviewed patients ≥15 years post-CTX. We (a) examined levels of HRQOL and positive psychological outcomes (posttraumatic growth related to CTX, purpose in life, life satisfaction) at follow-up, (b) evaluated change since transplant with mixed-effects models, and (c) identified psychosocial and clinical correlates of study outcomes with multivariable regression. RESULTS: Of 77 survivors, 64 (83%) were assessed (35 heart, 29 lung recipients; 15-19 years post-CTX). Physical HRQOL was poorer than the general population norm and earlier post-transplant levels (P's < .001). Mental HRQOL exceeded the norm (P < .001), with little temporal change (P = .070). Mean positive psychological outcome scores exceeded scales' midpoints at follow-up. Life satisfaction, assessed longitudinally, declined over time (P < .001) but remained similar to the norm at follow-up. Recent hospitalization and dyspnea increased patients' likelihood of poor physical HRQOL at follow-up (P's ≤ .022). Lower sense of mastery and poorer caregiver support lessened patients' likelihood of positive psychological outcomes (P's ≤ .049). Medical comorbidities and type of CTX were not associated with study outcomes at follow-up. CONCLUSIONS: Despite physical HRQOL impairment, long-term CTX survivors otherwise showed favorable outcomes. Clinical attention to correlates of HRQOL and positive psychological outcomes may help maximize survivors' well-being.

Artificial Intelligence and Mechanical Circulatory Support.

Advances in machine learning algorithms and computing power have fueled a rapid increase in artificial intelligence research in health care, including mechanical circulatory support. In this review, we highlight the needs for artificial intelligence in the mechanical circulatory support field and summarize existing artificial intelligence applications in 3 areas: identifying patients appropriate for mechanical circulatory support therapy, predicting risks after mechanical circulatory support device implantation, and monitoring for adverse events. We address the challenges of incorporating artificial intelligence in daily clinical practice and recommend demonstration of artificial intelligence tools' clinical efficacy, reliability, transparency, and equity to drive implementation.

Induction Immunosuppression and Renal Outcomes in Adult Heart Transplantation.

BACKGROUND: This study explores the use of induction therapy in orthotopic heart transplantation as it relates to preoperative renal function and evaluates the impact of its utilization on post-transplant outcomes. METHODS: We conducted a retrospective analysis using the United Network for Organ Sharing database from 2000 to 2018 evaluating the initiation of de novo dialysis after transplantation. We examined the relationship between induction immunosuppression and pre-transplant estimated glomerular filtration rate with post-transplant outcomes, accounting for inter-center variability through a mixed-effects logistic regression model. RESULTS: In total, 16,201 patients were included with a median age of 57 y (interquartile range 47, 63); 26% were women (n = 4222) and 28% (n = 4552) had a history of diabetes mellitus. The median estimated glomerular filtration rate (eGFR) was 67.5 mL/min (interquartile range 53.1, 86.7); 51.2% (n = 3068) of the recipients with eGFR < 60 received induction therapy compared to 42.5% (n = 4336) within the eGFR ≥ 60 group (P < 0.001). Adjusted multivariable analysis found that induction therapy was associated with de novo dialysis (odds ratio 1.25, 95% confidence interval 1.10-1.43, P < 0.001), with the most significant effect on patients with eGFR ≥ 60. Although significant, there was a weak correlation between center-level induction utilization and mean eGFR (r = -0.2, P < 0.001). CONCLUSION: In this analysis, the use of induction immunosuppression in orthotopic heart transplantation varied widely between centers and did not correlate strongly with pre-transplant eGFR. In addition, its utilization did not mitigate the risk of renal replacement therapy after transplantation and in fact was associated with increased risk even after adjusting for confounders most notably in patients with eGFR ≥ 60.

Geographic disparities in heart transplantation persist under the new allocation policy.

BACKGROUND: This study evaluated the impact of the 2018 heart allocation policy change on geographic disparities in United States orthotopic heart transplantation (OHT). METHODS: The United Network for Organ Sharing registry was queried to measure geographic disparity in OHT rates between pre-policy and post-policy change eras. We performed multilevel Poisson regression to measure region-level OHT rates. We derived an allocation priority-adjusted median incidence rate ratio (MIRR) for each policy era, a measure of median change in OHT rates between regions. RESULTS: 5958.78 waitlist person-years were analyzed, comprising 6596 OHT procedures (3890 pre-policy and 2706 post-policy). Median region-level OHT rate was .94 transplants/person-years before and 1.51 transplants/person-years after the policy change (P < .001). The unadjusted OHT MIRR across regions was 1.29 (95% CI 1.00-1.50) pre-policy change and 1.17 (95% CI 1.00-1.43) post-policy change, suggesting that the region-related variance in OHT rates decreased under the new allocation. After adjustment for allocation priority risk factors, the MIRR pre-policy change was 1.13 (95% CI 1.01-1.32) and post-policy change was 1.15 (95% CI 1.00-1.35). CONCLUSIONS: Geography accounts for ∼10% of the disparity among United States OHT rates. Despite broader heart sharing, the updated allocation policy did not substantially alter the existing geographic disparities among OHT recipients.

A mortality risk score for septuagenarians undergoing orthotopic heart transplantation.

BACKGROUND: With septuagenarians undergoing orthotopic heart transplantation (OHT) more frequently, we aimed to develop a risk score for 1-year mortality in this population. METHODS: Septuagenarian OHT recipients were identified from the UNOS registry between 1987 and 2018. The primary outcome was 1-year post-OHT mortality. Patients were randomly divided into derivation and validation cohorts. Associated covariates were entered into a multivariable logistic regression model. A risk score was created using the magnitudes of the odds ratios from the derivation cohort, and its 1-year post-OHT mortality prediction capacity was tested in the validation cohort. RESULTS: A total of 1156 septuagenarians were included, and they were randomly divided into derivation (66.7%, n = 771) and validation (33.3%, n = 385) cohorts. An 11-point risk score incorporating 4 variables was created, which included mechanical ventilation, serum bilirubin, serum creatinine, and donor age. The predicted 1-year mortality ranged from 4.2% (0 points) to 48.1% (11-points) (p < .001). After cross-validation, the c-index was 0.67 with a Brier score of 0.10. Risk scores above 3 points portended a survival disadvantage at 1-year follow-up (p < .001). CONCLUSIONS: This 11-point risk score for septuagenarians is predictive of mortality within 1-year of OHT and has potential utilization in improving recipient evaluation and selection of elderly patients.

Impact of various sizing metrics on female donor to male recipient heart transplant outcomes.

BACKGROUND: This study evaluated the impact of various sizing metrics on outcomes of female donor to male recipient orthotopic heart transplantation (OHT). METHODS: We queried the United Network of Organ Sharing database to analyze all isolated, primary adult OHTs from January 1, 2010 to January 20, 020. Patients were stratified by donor-recipient sex pairing. Logistic regression was used to investigate risk-adjusted effects of current size matching criteria (weight ratio, body mass index [BMI] ratio, predicted heart mass [pHM] ratio) on 1-year posttransplant mortality. Kaplan-Meier analysis was used to compare posttransplant survival among cohorts. RESULTS: A total of 22,450 patients were analyzed, of which 3019 (13.4%) underwent female-to-male transplantation. Of sex-matched pairs, female-to-male donation had the lowest proportion of undersized hearts using weight and BMI ratio metrics (10.5% and 5.2%) but had the highest proportion of undersizing using pHM metrics (48.1%) (all p < 0.001). Female-to-male recipients had the lowest rate of unadjusted 1-year survival (90.0%, p = 0.0169), and increased hazards of mortality after risk adjustment (odds ratio [OR]: 1.17, 95% confidence interval [CI]: 1.01-1.36, p = 0.034). Undersizing using pHM (donor-recipient ratio <0.85) was the only metric found to be associated in increased mortality after risk adjustment (OR: 1.32, 95% CI: 1.02-1.71, p = 0.035). CONCLUSION: Female-to-male heart transplantation has the worst survival of all sex-matching combinations. Although female donors in this cohort are appropriately sized using traditional metrics, half are under-sized using pHM. This, combined with its strong association with mortality, underscores the importance of routine pHM assessment when evaluating female donors for male recipients.

Trends in the utilization of marginal donors for orthotopic heart transplantation.

BACKGROUND: This study explored trends in utilization of marginal donors for orthotopic heart transplantation (OHT) in the United States. METHODS: Using the United Network for Organ Sharing database, adults (≥18 years) undergoing OHT between 2009 and 2019 were identified. Marginal donors were defined as having ≥2 of the following: age ≥50 years, ejection fraction less than 50%, ischemic time greater than 240 min, donor-to-recipient body mass index ratio less than 0.8, or donor inotrope use. Kaplan-Meier analysis was utilized to model survival with multivariable Cox regression analysis used for risk-adjustment. RESULTS: A total of 23,580 recipients underwent OHT with 4896 (20.76%) receiving organs from marginal donors. The use of marginal donors decreased from 25.6% in 2009 to 16.0% in 2017 but accounted for 24.7% of OHTs in 2019. This recent increase in marginal donor use was largely attributable to increased use of donors with ischemic time greater than 240 min, whereas other marginal donor criteria remained stable. Among 140 centers, median marginal donor use was 20.07% (interquartile range, 14.17%-26.51%). An increasing proportion of marginal donors was not associated with increased center-level OHT volume (R2 < 0.001, p = .833). Marginal donor use was associated with reduced 1- (88.75% vs. 91.87%) and 5-year survival (76.73% vs. 80.08%, p < .001). Following adjustment, marginal donor use remained a significant predictor of post-OHT mortality (hazard ratio, 1.17; p < .001). CONCLUSION: Marginal donors account for approximately 20% of OHTs performed in the United States. Despite a reduction in utilization over the past decade, the 2018 allocation change has resulted in a significant increase in use, largely attributable to longer ischemic times.

A mortality risk score for heart transplants after contemporary ventricular assist device bridging.

BACKGROUND: We sought to derive a risk score for 1-year mortality following orthotopic heart transplantation (OHT) in patients bridged with a contemporary centrifugal left ventricular assist device (LVAD). METHODS: Adult patients (≥18 years) in the United Network for Organ Sharing database undergoing OHT between 2010 and 2019 who were bridged with a HeartWare or HeartMate III device were included. Derivation and validation cohorts were randomly assigned with a 2:1 ratio. Threshold analysis and multivariable logistic regression were utilized to obtain adjusted odds ratios for 1-year post-OHT mortality. A risk score was generated using these adjusted odds ratios in the derivation cohort and the predictive performance of the composite index was evaluated in the validation set. RESULTS: A total of 3434 patients were identified. In the derivation cohort, the mean age was 53.5 ± 12.1 years and 1758 (76.8%) were male; 1789 (78.1%) were bridged with a HeartWare device. Multivariable logistic regression revealed that recipient age ≥50 years, bilirubin level ≥2.4 mg/dl, ischemic time ≥4 h, and preoperative hemodialysis predicted 1-year post-transplant mortality. Stratification into risk groups in the validation cohort revealed significant differences in postoperative renal failure, stroke, and short-term mortality. One-year post-transplant mortality was 5%, 6.7%, and 14.8% in the low-, moderate-, and high-risk categories, respectively (p < .001). CONCLUSIONS: Among patients bridged to OHT with newer generation centrifugal LVADs, older age, increasing bilirubin, longer ischemic time, and pre-OHT dialysis independently predicted post-transplant mortality. The composite risk score based on these factors may assist in patient selection and prognostication in those supported with contemporary LVADs.

The impact of socioeconomic status in patients with left ventricular assist devices (LVADs).

BACKGROUND: Socioeconomic status (SES) can be a powerful predictor of adverse outcomes among heart failure patients but its impact on survival and readmission following left ventricular assist device (LVAD) implantation surgery is poorly understood. We investigated if the LVAD recipients from more deprived neighborhoods experienced higher mortality and readmission rate after device implantation as compared to those from less deprived areas. METHODS: This is a single center, retrospective analysis evaluating adults who received Heartmate III and Heartware HVAD implants between 2009 and 2018. SES indicators were area of deprivation index (ADI), race and income. Our cohort was grouped by ADI quartiles from least deprived (Q1), Q2, Q3 to the most deprived (Q4). Outcomes included overall mortality and readmission following surgery. RESULTS: A total of 191 patients were included in the study. Demographics by SES indicators demonstrated that least deprived (Q1) patients were older than the most deprived (65 vs. 57, p < .01), African-American patients originated from more deprived neighborhoods than Caucasians (ADI 87 vs. 62, p < .001), and high-income patients had higher preoperative BUN and creatinine. Outcome differences included a decreased risk of death in most deprived patients (Q4) compared to the least deprived (Q1), however after adjusting for age, LVAD indication, and INTERMACS profile this was no longer significant. No differences in survival or readmission by race or income was observed CONCLUSION: SES does not independently impact survival and readmission after Heartware HVAD and Heartmate III LVAD implantation. More studies are needed to evaluate if other SES factors affect these outcomes.