Single center utilization and post-transplant outcomes of thoracoabdominal normothermic regional perfusion deceased cardiac donor organs.

INTRODUCTION: Thoracoabdominal normothermic regional perfusion (TA-NRP) following cardiac death is an emerging multivisceral organ procurement technique. Recent national studies on outcomes of presumptive TA-NRP-procured organs are limited by potential misclassification since TA-NRP is not differentiated from donation after cardiac death (DCD) in registry data. METHODS: We studied 22 donors whose designees consented to TA-NRP and organ procurement performed at our institution between January 20, 2020 and July 3, 2022. We identified these donors in SRTR to describe organ utilization and recipient outcomes and compared them to recipients of traditional DCD (tDCD) and donation after brain death (DBD) organs during the same timeframe. RESULTS: All 22 donors progressed to cardiac arrest and underwent TA-NRP followed by heart, lung, kidney, and/or liver procurement. Median donor age was 41 years, 55% had anoxic brain injury, 45% were hypertensive, 0% were diabetic, and median kidney donor profile index was 40%. TA-NRP utilization was high across all organ types (88%-100%), with a higher percentage of kidneys procured via TA-NRP compared to tDCD (88% vs. 72%, p = .02). Recipient and graft survival ranged from 89% to 100% and were comparable to tDCD and DBD recipients (p ≥ .2). Delayed graft function was lower for kidneys procured from TA-NRP compared to tDCD donors (27% vs. 44%, p = .045). CONCLUSION: Procurement from TA-NRP donors yielded high organ utilization, with outcomes comparable to tDCD and DBD recipients across organ types. Further large-scale study of TA-NRP donors, facilitated by its capture in the national registry, will be critical to fully understand its impact as an organ procurement technique.

Cardiac allograft vasculopathy in heart transplant recipients from hepatitis C viremic donors.

BACKGROUND: Recent studies suggest the transplantation of Hepatitis C (HCV) hearts from viremic donors is associated with comparable 1 year survival to nonviremic donors. Though HCV viremia is a known risk factor for accelerated atherosclerosis, data on cardiac allograft vasculopathy (CAV) outcomes are limited. We compared the incidence of CAV in heart transplant recipients from HCV viremic donors (nucleic acid amplification test positive; NAT+) compared to non-HCV infected donors (NAT-). METHODS: We retrospectively reviewed annual coronary angiograms with intravascular ultrasound from April 2017 to August 2020 at two large cardiac transplant centers. CAV was graded according to ISHLT guidelines. Maximal intimal thickness (MIT) ≥ 0.5 mm was considered significant for subclinical disease. RESULTS: Among 270 heart transplant recipients (mean age 54; 77% male), 62 patients were transplanted from NAT+ donors. CAV ≥ grade 1 was present in 8.8% of the NAT+ versus 16.8% of the NAT- group at 1 year, 20% versus 28.8% at 2 years, and 33.3% versus 41.5% at 3 years. After adjusting for donor age, donor smoking history, recipient BMI, recipient, hypertension, and recipient diabetes, NAT+ status did not confer increased risk of CAV (HR.80; 95% CI.45-1.40, p = 0.43) or subclinical IVUS disease (HR.87; 95% CI.58-1.30, p = 0.49). Additionally, there was no difference in the presence of rapidly progressive lesions on IVUS. CONCLUSION: Our data show that NAT+ donors conferred no increased risk for early CAV or subclinical IVUS disease following transplantation in a cohort of heart transplant patients who were treated for HCV, suggesting the short-term safety of this strategy to maximize the pool of available donor hearts.

The Cardiac Amyloidosis Registry Study (CARS): Rationale, Design and Methodology.

BACKGROUND: CARS (Cardiac Amyloidosis Registry Study) is a multicenter registry established in 2019 that includes patients with transthyretin (ATTR, wild-type and variant) and light chain (AL) cardiac amyloidosis (CA) evaluated at major amyloidosis centers between 1997 and 2025. CARS aims to describe the natural history of CA with attention to clinical and diagnostic variables at the time of diagnosis, real-world treatment patterns, and associated outcomes of patients in a diverse cohort that is more representative of the at-risk population than that described in CA clinical trials. METHODS AND RESULTS: This article describes the design and methodology of CARS, including procedures for data collection and preliminary results. As of February 2023, 20 centers in the United States enrolled 1415 patients, including 1155 (82%) with ATTR and 260 (18%) with AL CA. Among those with ATTR, wild-type is the most common ATTR (71%), and most of the 305 patients with variant ATTR have the p.V142I mutation (68%). A quarter of the total population identifies as Black. More individuals with AL are female (39%) compared to those with ATTR (13%). CONCLUSIONS: CARS will answer crucial clinical questions about CA natural history and permit comparison of different therapeutics not possible through current clinical trials. Future international collaboration will further strengthen the validity of observations of this increasingly recognized condition.

Long-term follow-up of acute and chronic rejection in heart transplant recipients from hepatitis C viremic (NAT+) donors.

The long-term safety of heart transplants from hepatitis C viremic (NAT+) donors remains uncertain. We conducted a prospective study of all patients who underwent heart transplantation at our center from January 2018 through August 2020. Routine testing was performed to assess for donor-derived cell-free DNA, acute cellular rejection (ACR), antibody-mediated rejection (AMR), and cardiac allograft vasculopathy (CAV). Allograft dysfunction and mortality were also monitored. Seventy-five NAT- recipients and 32 NAT+ recipients were enrolled in the study. All NAT+ recipients developed viremia detected by PCR, were treated with glecaprevir/pibrentasvir at the time of viremia detection, and cleared the virus by 59 days post-transplant. Patients who underwent NAT testing starting on post-operative day 7 (NAT+ Group 1) had significantly higher viral loads and were viremic for a longer period compared with patients tested on post-operative day 1 (NAT+ Group 2). Through 3.5 years of follow-up, there were no statistically significant differences in timing, severity, or frequency of ACR in NAT+ recipients compared with the NAT- cohort, nor were there differences in noninvasive measures of graft injury, incidence or severity of CAV, graft dysfunction, or mortality. There were five episodes of AMR, all in the NAT- group. There were no statistically significant differences between Group 1 and Group 2 NAT+ cohorts. Overall, these findings underscore the safety of heart transplantation from NAT+ donors.

Pre-transplant immune cell function assay as a predictor of early cardiac allograft rejection.

INTRODUCTION: ImmuKnow, an immune cell function assay that quantifies overall immune system activity can assist in post-transplant immunosuppression adjustment. However, the utility of pre-transplant ImmuKnow results representing a patient's baseline immune system activity is unknown. This study sought to assess if pre-transplant ImmuKnow results are predictive of rejection at the time of first biopsy in our cardiac transplant population. METHODS: This is a single center, retrospective observational study of consecutive patients from January 1, 2018 to October 1, 2020 who underwent orthotopic cardiac transplantation at NYU Langone Health. Patients were excluded if a pre-transplant ImmuKnow assay was not performed. ImmuKnow results were categorized according to clinical interpretation ranges (low, moderate, and high activity), and patients were divided into two groups: a low activity group versus a combined moderate-high activity group. Pre-transplant clinical characteristics, induction immunosuppression use, early postoperative tacrolimus levels, and first endomyocardial biopsy results were collected for all patients. Rates of clinically significant early rejection (defined as rejection ≥ 1R/1B) were compared between pre-transplant ImmuKnow groups. RESULTS: Of 110 patients who underwent cardiac transplant, 81 had pre-transplant ImmuKnow results. The low ImmuKnow activity group was comprised of 15 patients, and 66 patients were in the combined moderate-high group. Baseline characteristics were similar between groups. Early rejection occurred in 0 (0%) patients with low pre-transplant ImmuKnow levels. Among the moderate- high pre-transplant ImmuKnow group, 16 (24.2%) patients experienced early rejection (P = .033). The mean ImmuKnow level in the non-rejection group was the 364.9 ng/ml of ATP compared to 499.3 ng/ml of ATP for those with rejection (P = .020). CONCLUSION: Patients with low pre-transplant ImmuKnow levels had lower risk of early rejection when compared with patients with moderate or high levels. Our study suggests a possible utility in performing pre-transplant ImmuKnow to identify patients at-risk for early rejection who may benefit from intensified upfront immunosuppression as well as to recognize those where slower calcineurin inhibitor initiation may be appropriate.

Missed Opportunities in Identifying Cardiomyopathy Aetiology Prior to Advanced Heart Failure Therapy.

BACKGROUND: Specific aetiologies of cardiomyopathy can significantly impact treatment options as well as appropriateness and prioritisation for advanced heart failure therapies such as ventricular assist device (VAD) or orthotopic heart transplantation (OHT). We reviewed the tissue diagnoses of patients who underwent advanced therapies for heart failure (HF) to identify diagnostic discrepancies. METHODS: This study presents a retrospective cohort of the aetiology of cardiomyopathy in 118 patients receiving either durable VAD or OHT. Discrepancies between the preoperative aetiological diagnosis of cardiomyopathy with the pathological diagnosis were recorded. Echocardiographic and haemodynamic data were reviewed to examine differences in patients with differing aetiological diagnoses. RESULTS: Twelve (12) of 118 (12/118) (10.2%) had a pathological diagnosis that was discordant with pre-surgical diagnosis. The most common missed diagnoses were infiltrative cardiomyopathy (5) and hypertrophic cardiomyopathy (3). Patients with misidentified aetiology of cardiomyopathy had smaller left ventricular (LV) dimensions on echocardiography than patients with dilated cardiomyopathy (5.8±0.9 vs 6.7±1.1 respectively p=0.01). CONCLUSIONS: Most HF patients undergoing VAD and OHT had a correct diagnosis for their heart failure prior to treatment, but a missed diagnosis at time of intervention (VAD or OHT) was not uncommon. Smaller LV dimension on echocardiogram in a patient with a non-ischaemic cardiomyopathy warrants further workup for a more specific aetiology.

Potential for donation after circulatory death heart transplantation in the United States: Retrospective analysis of a limited UNOS dataset.

Donation after Circulatory Death (DCD) is an alternative to Donation after Brain death (DBD), and is a growing strategy for organ procurement in the United States(US). The purpose of this analysis was to review the number and quality of hearts in one United Network for Organ Sharing (UNOS) Region that were not utilized as a potential consequence of nonheart DCD donation. We retrospectively identified all successful US DCD solid organ donors from 1/2011 to 3/1/2017, defined an ideal heart donor by age and left ventricular ejection fraction (LVEF), and then reviewed the donor charts of unused hearts in New York and Vermont (UNOS Region 9). Of 8302 successful DCD donors across the United States, 5033 (61%) were between 18 and 49 years of age, and 872 had a screening echocardiogram, with 573 (66%) measuring an EF >50%. Of these 573 potential donors, 44 (7.7%) were from Region 9. Detailed donor chart review identified 36 ideal heart donors, 24 (66.7%) with anoxic brain injury. Trends in Region 9 DCD donation increased from 4 unused hearts in 2011, to 13 in 2016. In the context of severe organ scarcity, these data indicate that implementation of DCD heart transplantation in the United States would improve overall donation rates and provide a pathway to utilize these ideal donor hearts.

Management and tolerability of glecaprevir-pibrentasvir pharmacotherapy in hepatitis C viremic heart and lung transplant recipients.

We conducted a retrospective review of thoracic transplant recipients (22 heart and 16 lung transplant recipients) prospectively enrolled in a single-center observational study of HCV NAT+ organ transplantation in HCV NAT- recipients. All recipients were treated with 8 weeks of glecaprevir-pibrentasvir (GP) for HCV viremia in addition to standard triple immunosuppression post-transplant. Thoracic transplant recipients of HCV NAT- organs were used as a control (24 heart and 22 lung transplant recipients). Our primary outcome was to assess the effect of GP on tacrolimus dose requirements. Secondary objectives included assessing drug interactions with common post-transplant medications, adverse effects, and the need to hold or discontinue GP therapy. The median tacrolimus concentration-to-dose ratio (CDR) in the cohort was 184 (99-260) during GP therapy and 154 (78-304) over the first month after GP (P = .79). Trends in median tacrolimus CDR were similar on a per-week basis and per-patient basis. In three instances, concomitant posaconazole and GP led to hyperbilirubinemia and interruption of posaconazole. GP therapy was held in one heart transplant recipient and discontinued in another due to unresolving hyperbilirubinemia. Utilization of GP to treat HCV viremia post-thoracic transplant is feasible and safe, but requires modifications to post-transplant pharmacotherapy and careful monitoring for adverse effects.

Outcomes of the Treatment with Glecaprevir/Pibrentasvir following heart transplantation utilizing hepatitis C viremic donors.

BACKGROUND: The use of direct-acting antivirals (DAA) has expanded transplantation from hepatitis C viremic donors (HCV-VIR). Our team has conducted an open-label, prospective trial to assess outcomes transplanting HCV viremic hearts. Glecaprevir/pibrentasvir (GLE/PIB) was our sole DAA. METHODS: Serial quantitative hepatitis C virus (HCV) RNA PCR was obtained to assess HCV viral titers. Between January 2018 and June 2019, a total of 50 recipients were transplanted. Of these, 22/50 (44%) were from HCV-VIR, the remaining 28 from non-viremic (HCV NON-VIR) donors. An 8-week course of GLE/PIB was initiated at 1 week post-transplant. RESULTS: There was no difference in demographic or clinical parameters between groups. All 22 recipients of HCV-VIR transplants became viremic. GLE/PIB was effective in decreasing viremia to undetectable levels by 6 weeks post-transplant in all patients. The median time to first undetectable HCV quantitative PCR was (4.3 weeks, IQR: 4-5.7 weeks). All patients demonstrated sustained undetectable viral load through 1-year follow-up. There was no difference in survival at one year between HCV NON-VIR 28/28: (100%) vs HCV-VIR 21/22 (95%) recipients. CONCLUSIONS: Our center reports excellent outcomes in transplanting utilizing hearts from HCV-VIR donors. No effect on survival or co-morbidity was found. An 8-week GLE/PIB course was safe and effective when initiated approximately 1 week post-transplant.

Comparison of device-specific adverse event profiles between Impella platforms.

BACKGROUND: The Impella (Abiomed) ventricular support system is a family of temporary mechanical circulatory support (MCS) devices used to treat patients with cardiogenic shock, acute cardiogenic decompensation, and for high-risk percutaneous or surgical revascularization. These devices include the percutaneously implanted 2.5/cardiac power (CP) and the surgically implanted 5.0/left direct (LD). Despite the beneficial effects and increased usage of these devices, data to assess adverse outcomes and guide clinician decision-making between the Impella CP and 5.0/LD are limited. METHODS: This is a retrospective analysis of 91 consecutive patients who required at least 24 h of Impella support, from January 1, 2015 to December 31, 2019. Groups were stratified based on either initial Impella CP or 5.0/LD placement. Clinical outcomes and in-hospital complications were compared. RESULTS: Impella CP was implanted in 66 patients (mean age: 61 ± 15 years, male 71.2%) and Impella 5.0/LD was implanted in 25 patients (mean age: 62 ± 9 years, male 84.0%). There was greater stability of device position (p = .033), less incidence of hemolysis (p < .001), and less frequent need for additional MCS (p = .001) in patients implanted with the Impella 5.0/LD compared with Impella CP in this study cohort. Patients with Impella 5.0/LD were more likely to survive from Impella and survive to discharge. CONCLUSIONS: This study suggests that for patients who require temporary MCS for more than 24 h, the Impella 5.0/LD may have a more favorable device-specific adverse profile compared with the Impella CP.

Diagnosis and treatment of heart failure in hereditary transthyretin amyloidosis.

Amyloidosis describes a family of related disease states associated with the extracellular tissue deposition of fibrils composed of low-molecular-weight subunits of a variety of proteins circulating as constituents of plasma. Depending on the disease subtype, fibrillar deposits in a several organs including the heart, kidney, liver, and peripheral nerves cause organ dysfunction and associated morbidity and mortality. The most common amyloid fibril deposits associated with cardiac manifestations are of monoclonal light-chain or transthyretin (ATTR) types. This review will focus on the ATTR types of cardiac amyloidosis. ATTR amyloidosis may be associated with abnormal metabolism of wild-type transthyretin (previously called senile systemic amyloidosis) or with hereditary variants in the transthyretin gene. Cardiac amyloidosis is often under-recognized in its early stages, and when a diagnosis of cardiac amyloidosis is made, patients are often at the advanced stages of the disease. Treatments now available appear to exert their benefit predominantly in individuals with the early stages of disease. Increased awareness and early diagnosis of cardiac amyloidosis and continued discovery of effective therapies will increase opportunities to improve clinical outcomes in this patient population.

Early Identification of Patients With Acute Decompensated Heart Failure.

BACKGROUND: Interventions to reduce readmissions after acute heart failure hospitalization require early identification of patients. The purpose of this study was to develop and test accuracies of various approaches to identify patients with acute decompensated heart failure (ADHF) with the use of data derived from the electronic health record. METHODS AND RESULTS: We included 37,229 hospitalizations of adult patients at a single hospital during 2013-2015. We developed 4 algorithms to identify hospitalization with a principal discharge diagnosis of ADHF: 1) presence of 1 of 3 clinical characteristics, 2) logistic regression of 31 structured data elements, 3) machine learning with unstructured data, and 4) machine learning with the use of both structured and unstructured data. In data validation, algorithm 1 had a sensitivity of 0.98 and positive predictive value (PPV) of 0.14 for ADHF. Algorithm 2 had an area under the receiver operating characteristic curve (AUC) of 0.96, and both machine learning algorithms had AUCs of 0.99. Based on a brief survey of 3 providers who perform chart review for ADHF, we estimated that providers spent 8.6 minutes per chart review; using this this parameter, we estimated that providers would spend 61.4, 57.3, 28.7, and 25.3 minutes on secondary chart review for each case of ADHF if initial screening were done with algorithms 1, 2, 3, and 4, respectively. CONCLUSIONS: Machine learning algorithms with unstructured notes had the best performance for identification of ADHF and can improve provider efficiency for delivery of quality improvement interventions.

Aortic root thrombus complicated by left main coronary artery occlusion visualized by 3D echocardiography in a patient with continuous-flow left ventricular assist device.

Aortic root thrombus is an uncommon complication of continuous-flow left ventricular assist devices (LVAD). We present the case of a 71-year-old man with ischemic cardiomyopathy who underwent destination therapy HeartMate II LVAD placement. Eighteen months later, he presented with a cerebrovascular accident followed by myocardial infarction. Transesophageal echocardiography revealed an aortic root thrombus spanning the left and noncoronary cusps and obliterating the left main coronary artery. We discuss the incidence, risk factors, and management of aortic root thrombus in LVAD patients. To our knowledge, this is the first report of three-dimensional echocardiography used to characterize an LVAD-associated aortic root thrombus.

Management of the in situ HeartMate II left ventricular assist device during non-transplant, non-exchange cardiac reoperations.

Cardiac surgery with cardiopulmonary bypass may be necessary in patients with pre-existing, continuous-flow, left ventricular assist devices. Heart transplantation or exchange of a malfunctioning left ventricular assist device are the most common scenarios. However, reoperation may also be needed for acquired valvular disease or device malposition. In these cases, operative strategies that enable safe conduct of cardiopulmonary bypass and, if needed, cardioplegic arrest while the left ventricular assist device remains in situ, are essential. Such strategies would avoid unnecessary replacement of working components of the left ventricular assist device and, importantly, avoid damage to them during the period of cardiopulmonary bypass. Adequate anticoagulation, avoidance of regurgitant flow into the device, prevention of blood stagnation in the hardware and careful deairing after periods of pump stoppage are key principles. We present a stepwise algorithm for the management of the HeartMate II device during such cases.

Management of Rapidly Ascending Driveline Tunnel Infection.

We present a case of rapidly ascending left ventricular assist device driveline and tunnel infection in a patient with a long length of driveline buried beyond the distal velour coating. Device salvage with radical debridement, exit site relocation, and local tissue advancement is described. The findings in this case suggest that the interface between nonvelour covered driveline and subcutaneous tissue can become the nidus of a virulent ascending infection because of poor tissue ingrowth.

Bridge to Transplantation: Policies Impact Practices.

Since the development of the first heart allocation system in 1988 to the most recent heart allocation system in 2018, the road to heart transplantation has continued to evolve. Policies were shaped with advances in temporary and durable left ventricular assist devices as well as prioritization of patients based on degree of illness. Herein, we review the changes in the heart allocation system over the past several decades and the impact of practice patterns across the United States.

Clinical management of takotsubo cardiomyopathy.

The clinical management of takotsubo cardiomyopathy is challenging. Its diagnosis must be made on clinical grounds and differentiated from alternative diagnoses with echocardiography, serum biomarkers, cardiac catheterization, and cardiac magnetic resonance imaging. Acute therapy includes supportive care, targeting the precipitating trigger if known, b-blockade, inhibitors of the renin-angiotensin system, and consideration of systemic anticoagulation in all patients. Recovery of left ventricular function to normal is expected regardless of early therapy. Although the prognosis is generally favorable, monitoring for early dangerous complications is essential. There is no evidence to support use of long-term medical therapy to reduce the risk of recurrence.

HHV-6 Myocarditis Progressing to Ventricular Standstill Requiring Cardiac Transplant.

Human herpesvirus-6 (HHV-6) is an increasingly recognized cause of myocarditis. We present the case of a 46-year-old woman who presented with fulminant HHV-6 myocarditis requiring heart transplantation. (Level of Difficulty: Advanced.).

The Society of Thoracic Surgeons Intermacs 2022 Annual Report: Focus on the 2018 Heart Transplant Allocation System.

The 13th annual report from The Society of Thoracic Surgeons (STS) Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) highlights outcomes for 27,314 patients receiving continuous-flow durable left ventricular assist devices (LVAD) during the last decade (2012-2021). In 2021, 2464 primary LVADs were implanted, representing a 23.5% reduction in the annual volume compared with peak implantation in 2019 and an ongoing trend from the prior year. This decline is likely a reflection of the untoward effects of the coronavirus disease 2019 pandemic and the change in the United States heart transplant allocation system in 2018. The last several years have been characterized by a shift in device indication and type, with 81.1% of patients now implanted as destination therapy and 92.7% receiving an LVAD with full magnetic levitation in 2021. However, despite an older, more ill population being increasingly supported preimplant with temporary circulatory devices in the recent (2017-2021) vs prior (2012-2016) eras, the 1- and 5-year survival continues to improve, at 83.0% and 51.9%, respectively. The adverse events profile has also improved, with a significant reduction in stroke, gastrointestinal bleeding, and hospital readmissions. Finally, we examined the impact of the change in the heart transplant allocation system in 2018 on LVAD candidacy, implant strategy, and outcomes. In the competing-outcomes analysis, the proportion of transplant-eligible patients receiving a transplant has declined from 56.5% to 46.0% at 3 years, whereas the proportion remaining alive with ongoing support has improved from 24.1% to 38.1% at 3 years, underscoring the durability of the currently available technology.