Antithrombotic Strategies With Left Ventricular Assist Devices.

Long-term outcomes of patients with advanced heart failure treated with durable left ventricular assist devices (LVADs) have been augmented due to improved durability and hemocompatibility on the backbone of pump engineering enhancements. The incidence of hemocompatibility-related adverse events (pump thrombosis, stroke and nonsurgical bleeding events) are device specific and vary by type of engineered pump. A fully magnetically levitated rotor containing LVAD in concert with use of antithrombotic therapy has successfully overcome an increased risk of pump thrombosis and stroke-risk, albeit with only modest reduction in bleeding events. Modifications to antithrombotic strategies have focused on reduced-dose vitamin K antagonist use or use of direct oral anticoagulants with demonstration of safety and progress in reduction of mucosal bleeding episodes with elimination of antiplatelet agents. This review outlines the current landscape of advances in anticoagulation management in LVAD patients, highlighting the need for ongoing research and cautious application of emerging therapies and technologies.

The Hemodynamic Effects of Aortic Regurgitation in Patients Supported by a HeartMate 3 Left Ventricular Assist Device.

BACKGROUND: Aortic regurgitation (AR) is a common complication following left ventricular assist device (LVAD) implantation. We evaluated the hemodynamic implications of AR in patients with HeartMate 3 (HM3) LVAD at baseline and in response to speed changes. METHODS AND RESULTS: Clinically stable outpatients supported by HM3 who underwent a routine hemodynamic ramp test were retrospectively enrolled in this analysis. Patients were stratified based on the presence of at least mild AR at baseline speed. Hemodynamic and echocardiographic parameters were compared between the AR and non-AR groups. Sixty-two patients were identified. At the baseline LVAD speed, 29 patients (47%) had AR, while 33 patients (53%) did not. Patients with AR were older and supported on HM3 for a longer duration. At baseline speed, all hemodynamic parameters were similar between the groups including central venous pressure, pulmonary capillary wedge pressure, pulmonary arterial pressures, cardiac output and index, and pulmonary artery pulsatility index (p > 0.05 for all). During the subacute assessment, AR worsened in some, but not all, patients, with increases in LVAD speed. There were no significant differences in 1-year mortality or hospitalization rates between the groups, however, at 1-year, ≥ moderate AR and right ventricular failure (RVF) were detected in higher rates among the AR group compared to the non-AR group (45% vs. 0%; p < 0.01, and 75% vs. 36.8%; p = 0.02, respectively). CONCLUSIONS: In a cohort of stable outpatients supported with HM3 who underwent a routine hemodynamic ramp test, the presence of mild or greater AR did not impact the ability of HM3 LVADs to effectively unload the left ventricle during early subacute assessment. Although the presence of AR did not affect mortality and hospitalization rates, it resulted in higher rates of late hemodynamic-related events in the form of progressive AR and RVF.

Experimentally Induced Peripheral Venous Congestion Exacerbates Inflammation, Oxidative Stress, and Neurohormonal and Endothelial Cell Activation in Patients With Systolic Heart Failure.

BACKGROUND: Venous congestion (VC) is a hallmark of symptomatic heart failure (HF) requiring hospitalization; however, its role in the pathogenesis of HF progression remains unclear. We investigated whether peripheral VC exacerbates inflammation, oxidative stress and neurohormonal and endothelial cell (EC) activation in patients with HF with reduced ejection fraction (HFrEF). METHODS AND RESULTS: Two matched groups of patients with HFrEF and with no peripheral VC vs without recent HF hospitalization were studied. We modeled peripheral VC by inflating a cuff around the dominant arm, targeting ∼ 30 mmHg increase in venous pressure (venous stress test [VST]). Blood and ECs were sampled before and after 90 minutes of VST. We studied 44 patients (age 53 ± 12 years, 32% female). Circulating endothelin-1, tumor necrosis factor-α, interleukin-6, isoprostane, angiotensin II (ang-2), angiopoietin-2, vascular cell adhesion molecule-1, and CD146 significantly increased after the VST. Enhanced endothelin-1 and angiopoietin-2 responses to the VST were present in patients with vs without recent hospitalization and were prospectively associated with incident HF-related events; 6698 messenger ribonucleic acid (mRNA probe sets were differentially expressed in ECs after VST. CONCLUSIONS: Experimental VC exacerbates inflammation, oxidative stress, neurohormonal and EC activation and promotes unfavorable transcriptome remodeling in ECs of patients with HFrEF. A distinct biological sensitivity to VC appears to be associated with high risk for HF progression.

Contemporary Immunosuppression Management and 1-Year Outcomes in Dual Organ Heart Transplantation.

BACKGROUND: There have been limited reports on immunosuppression strategies and outcomes in dual organ heart transplant populations, primarily from before the 2018 United Network for Organ Sharing (UNOS) heart allocation policy change. Recent data suggested that outcomes with heart-lung and heart-liver transplants remained comparable in the new allocation era, yet heart-kidney recipients have worse 1-year survival. METHODS: This single-center retrospective study evaluated adult heart-kidney, heart-liver, and heart-lung transplant recipients from September 2019 to May 2023. Immunosuppression regimen, infectious complications, and graft outcomes were collected for 12 months. RESULTS: A total of 36 patients (kidney n = 20, liver n = 9, and lung n = 7) were included in this study. Basiliximab was the most commonly employed induction strategy across the organ groups (12/20 in kidney, 4/9 in liver, and 7/7 in lung). All patients were on triple immunosuppression at 12 months posttransplant with prednisone wean achieved in one heart-liver recipient. Infection complications were frequently reported (95% kidney, 75% liver, 100% lung group). One patient went back to dialysis due to focal segmental glomerulosclerosis. One chronic lung allograft dysfunction was reported, but no other severe biopsy-proven rejection or retransplant was reported. The 1-year survival was 85% (17/20) in heart-kidney, 78% (7/9) in heart-liver, and 86% (6/7) in heart-lung recipients. CONCLUSION: This study summarized real-world immunosuppression strategies and outcomes in dual organ heart transplant recipients.

A change of heart: Characteristics and outcomes of multiple cardiac retransplant recipients.

BACKGROUND: Among heart transplant (HT) recipients who develop advanced graft dysfunction, cardiac re-transplantation may be considered. A smaller subset of patients will experience failure of their second allograft and undergo repeat re-transplantation. Outcomes among these individuals are not well-described. METHODS: Adult and pediatric patients in the United Network for Organ Sharing (UNOS) registry who received HT between January 1, 1990 and December 31, 2020 were included. RESULTS: Between 1990 and 2020, 90 individuals received a third HT and three underwent a fourth HT. Recipients were younger than those undergoing primary HT (mean age 32 years). Third HT was associated with significantly higher unadjusted rates of 1-year mortality (18% for third HT vs. 13% for second HT vs. 9% for primary HT, p < .001) and 10-year mortality (59% for third HT vs. 42% for second HT vs. 37% for primary HT, p < .001). Mortality was highest amongst recipients aged >60 years and those re-transplanted for acute graft failure. Long-term rates of CAV, rejection, chronic dialysis, and hospitalization for infection were also higher. CONCLUSIONS: Third HT is associated with higher morbidity and mortality than primary HT. Further consensus is needed regarding appropriate organ stewardship for this unique subgroup.

Cardio-Renal-Metabolic Outcomes Associated With the Use of GLP-1 Receptor Agonists After Heart Transplantation.

BACKGROUND: The use of glucagon-like-peptide 1 receptor agonists (GLP1-RA) has dramatically increased over the past 5 years for diabetes mellitus type 2 (T2DM) and obesity. These comorbidities are prevalent in adult heart transplant (HT) recipients. However, there are limited data evaluating the efficacy of this drug class in this population. The aim of the current study was to describe cardiometabolic changes in HT recipients prescribed GLP1-RA at a large-volume transplant center. METHODS: We retrospectively reviewed all adult HT recipients who received GLP1-RA after HT for a minimum of 1-month. Cardiometabolic parameters including body mass index (BMI), lipid panel, hemoglobin A1C, estimated glomerular filtration rate (eGFR), and NT-proBNP were compared prior to initiation of the drug and at most recent follow-up. We also evaluated for significant dose adjustments to immunosuppression after drug initiation and adverse effects leading to drug discontinuation. RESULTS: Seventy-four patients were included (28% female, 53% White, 20% Hispanic) and followed for a median of 383 days [IQR 209, 613] on a GLP1-RA. The majority of patients (n = 56, 76%) were prescribed semaglutide. The most common indication for prescription was T2DM alone (n = 33, 45%), followed by combined T2DM and obesity (n = 26, 35%). At most recent follow-up, mean BMI decreased from 33.3 to 31.5 kg/m2 (p < 0.0001), HbA1C from 7.3% to 6.7% (p = 0.005), LDL from 78.6 to 70.3 mg/dL (p = 0.018) and basal insulin daily dose from 32.6 to 24.8 units (p = 0.0002). CONCLUSION: HT recipients prescribed GLP1-RA therapy showed improved glycemic control, weight loss, and cholesterol levels during the study follow-up period. GLP1-RA were well tolerated and were rarely associated with changes in immunosuppression dosing.

Comparative Analysis of Ischemia-Reperfusion Injury in Heart Transplantation: A Single-Center Study Evaluating Conventional Ice-Cold Storage versus the Paragonix SherpaPak Cardiac Transport System.

BACKGROUND: Since the 2018 allocation system change in heart transplantation (HT), ischemic times have increased, which may be associated with peri-operative and post-operative complications. This study aimed to compare ischemia reperfusion injury (IRI) in hearts preserved using ice-cold storage (ICS) and the Paragonix SherpaPak TM Cardiac Transport System (CTS). METHODS: From January 2021 to June 2022, consecutive endomyocardial biopsies from 90 HT recipients were analyzed by a cardiac pathologist in a single-blinded manner: 33 ICS and 57 CTS. Endomyocardial biopsies were performed at three-time intervals post-HT, and the severity of IRI manifesting histologically as coagulative myocyte necrosis (CMN) was evaluated, along with graft rejection and graft function. RESULTS: The incidence of IRI at weeks 1, 4, and 8 post-HT were similar between the ICS and CTS groups. There was a 59.3% statistically significant reduction in CMN from week 1 to 4 with CTS, but not with ICS. By week 8, there were significant reductions in CMN in both groups. Only 1 out of 33 (3%) patients in the ICS group had an ischemic time >240 mins, compared to 10 out of 52 (19%) patients in the CTS group. During the follow-up period of 8 weeks to 12 months, there were no significant differences in rejection rates, formation of de novo donor-specific antibodies and overall survival between the groups. CONCLUSION: The CTS preservation system had similar rates of IRI and clinical outcomes compared to ICS despite longer overall ischemic times. There is significantly more recovery of IRI in the early post operative period with CTS. This study supports CTS as a viable option for preservation from remote locations, expanding the donor pool.

Utility of a fusion protein T-cell co-stimulation blocker Belatacept in heart transplant recipients: Real world experience from a high volume center.

BACKGROUND: Belatacept (BTC), a fusion protein, selectively inhibits T-cell co-stimulation by binding to the CD80 and CD86 receptors on antigen-presenting cells (APCs) and has been used as immunosuppression in adult renal transplant recipients. However, data regarding its use in heart transplant (HT) recipients are limited. This retrospective cohort study aimed to delineate BTC's application in HT, focusing on efficacy, safety, and associated complications at a high-volume HT center. METHODS: A retrospective cohort study was conducted of patients who underwent HT between January 2017 and December 2021 and subsequently received BTC as part of their immunosuppressive regimen. Twenty-one HT recipients were identified. Baseline characteristics, history of rejection, and indication for BTC use were collected. Outcomes included renal function, graft function, allograft rejection and mortality. Follow-up data were collected through December 2023. RESULTS: Among 776 patients monitored from January 2017 to December 2021 21 (2.7%) received BTC treatment. Average age at transplantation was 53 years (± 12 years), and 38% were women. BTC administration began, on average, 689 [483, 1830] days post-HT. The primary indications for BTC were elevated pre-formed donor-specific antibodies in highly sensitized patients (66.6%) and renal sparing (23.8%), in conjunction with reduced calcineurin inhibitor dosage. Only one (4.8%) patient encountered rejection within a year of starting BTC. Graft function by echocardiography remained stable at 6 and 12 months posttreatment. An improvement was observed in serum creatinine levels (76.2% of patients), decreasing from a median of 1.58 to 1.45 (IQR [1.0-2.1] to [1.1-1.9]) over 12 months (p = .054). eGFR improved at 3 and 6 months compared with 3 months pre- BTC levels; however, this was not statistically significant (p = .24). Treatment discontinuation occurred in seven patients (33.3%) of whom four (19%) were switched back to full dose CNI. Infections occurred in 11 patients (52.4%), leading to BTC discontinuation in 4 patients (19%). CONCLUSION: In this cohort, BTC therapy was used as alternative immunosuppression for management of highly sensitized patients or for renal sparing. BTC therapy when combined with CNI dose reduction resulted in stabilization in renal function as measured through renal surrogate markers, which did not, however, reach statistical significance. Patients on BTC maintained a low rejection rate and preserved graft function. Infections were common during BTC therapy and were associated with medication pause/discontinuation in 19% of patients. Further randomized studies are needed to assess the efficacy and safety of BTC in HT recipients.

Clinical attachment loss is cross-sectionally associated with elevated glucose among adults without diabetes.

AIM: We investigated whether periodontal measures are cross-sectionally associated with prediabetes and cardiometabolic biomarkers among non-diabetic younger adults. MATERIALS AND METHODS: One thousand seventy-one participants (mean age = 32.2 years [SE = 0.3]; 73% female) from the Oral Infections, Glucose Intolerance and Insulin Resistance Study were enrolled. Full-mouth clinical attachment loss (fm-CAL), probing depth (fm-PD) and bleeding on probing were ascertained. Interproximal CAL (i-CAL) and probing depths (i-PD) served as our primary exposures. Glucose, HbA1c, insulin and insulin resistance (HOMA-IR) outcomes were assessed from fasting blood. Prediabetes was defined per American Diabetes Association guidelines. Prediabetes prevalence ratios (PR [95% CI]) and mean [SE] cardiometabolic biomarkers were regressed on periodontal variables via multivariable robust variance Poisson regression or multivariable linear regression. RESULTS: Prevalence of prediabetes was 12.5%. Fully adjusted prediabetes PR in Tertiles 3 versus 1 of mean i-CAL was 2.42 (1.77, 3.08). Fully adjusted fasting glucose estimates across i-CAL tertiles were 83.29 [0.43], 84.31 [0.37], 86.48 [0.46]; p for trend <.01. Greater percent of sites with i-PD ≥3 mm showed elevated natural-log-HOMA-IR after adjustment (0%-12% of sites = 0.33 [0.03], 13%-26% of sites = 0.39 [0.03], ≥27% of sites = 0.42 [0.03]; p for trend = .04). CONCLUSIONS: i-CAL (vs. fm-CAL) was associated with elevated fasting glucose and prediabetes, whereas i-PD (vs. fm-PD) was associated with insulin resistance. Future studies are needed to examine periodontal disease and incident prediabetes.

Pre-operative pectoralis muscle area index is associated with biomarkers of inflammation and endotoxemia and predicts clinical outcomes after left ventricular assist device implantation: A cohort study.

BACKGROUND: Pre-left ventricular assist device (LVAD) pectoralis muscle assessment, an estimate of sarcopenia, has been associated with postoperative mortality and gastrointestinal bleeding, though its association with inflammation, endotoxemia, length-of-stay (LOS), and readmissions remains underexplored. METHODS: This was a single-center cohort study of LVAD patients implanted 1/2015-10/2018. Preoperative pectoralis muscle area was measured on chest computed tomography (CT), adjusted for height squared to derive pectoralis muscle area index (PMI). Those with PMI in the lowest quintile were defined as low-PMI cohort; all others constituted the reference cohort. Biomarkers of inflammation (interleukin-6, adiponectin, tumor necrosis factor-α [TNFα]) and endotoxemia (soluble (s)CD14) were measured in a subset of patients. RESULTS: Of the 254 LVAD patients, 95 had a preoperative chest CT (median days pre-LVAD: 7 [IQR 3-13]), of whom 19 (20.0%) were in the low-PMI cohort and the remainder were in the reference cohort. Compared with the reference cohort, the low-PMI cohort had higher levels of sCD14 (2594 vs. 1850 ng/mL; p = 0.04) and TNFα (2.9 vs. 1.9 pg/mL; p = 0.03). In adjusted analyses, the low-PMI cohort had longer LOS (incidence rate ratio 1.56 [95% confidence interval 1.16-2.10], p = 0.004) and higher risk of 90-day and 1-year readmissions (subhazard ratio 5.48 [1.88-16.0], p = 0.002; hazard ratio 1.73 [1.02-2.94]; p = 0.04, respectively). CONCLUSIONS: Pre-LVAD PMI is associated with inflammation, endotoxemia, and increased LOS and readmissions.

Unplanned hospital readmissions following HeartMate 3 implantation: Readmission rates, causes, and impact on survival.

BACKGROUND: Hospital readmissions following left ventricular assist device (LVAD) remain a frequent comorbidity, associated with decreased quality of life and increased resources utilization. This study sought to determine causes, predictors, and impact on survival of hospitalizations during HeartMate 3 (HM3) support. METHODS: All patients implanted with HM3 between November 2014 to December 2019 at Columbia University Irving Medical Center were consecutively enrolled in the study. Demographics and clinical characteristics from the index admission and the first outpatient visit were collected and used to estimate 1-year and 900-day readmission-free survival and overall survival. Multivariable analysis was performed for subsequent readmissions. RESULTS: Of 182 patients who received a HM3 LVAD, 167 (92%) were discharged after index admission and experienced 407 unplanned readmissions over the median follow up of 727 (interquartile range (IQR): 410.5, 1124.5) days. One-year and 900-day mean cumulative number of all-cause unplanned readmissions was 0.43 (95%CI, 0.36, 0.51) and 1.13 (95%CI, 0.99, 1.29). The most frequent causes of rehospitalizations included major infections (29.3%), bleeding (13.2%), device-related (12.5%), volume overload (7.1%), and other (28%). One-year and 900-day survival free from all-cause readmission was 38% (95%CI, 31-46%) and 16.6% (95%CI, 10.3-24.4%). One-year and 900-day freedom from 2, 3, and ≥4 readmissions were 60.7%, 74%, 74.5% and 26.2%, 33.3%, 41.3%. One-year and 900-day survival were unaffected by the number of readmissions and remained >90%. Male sex, ischemic etiology, diabetes, lower serum creatinine, longer duration of index hospitalization, and a history of readmission between discharge and the first outpatient visit were associated with subsequent readmissions. CONCLUSIONS: Unplanned hospital readmissions after HM3 are common, with infections and bleeding accounting for the majority of readmissions. Irrespective of the number of readmissions, one-year survival remained unaffected.

The Difference Between Cystatin C- and Creatinine-Based Estimated GFR in Heart Failure With Reduced Ejection Fraction: Insights From PARADIGM-HF.

RATIONALE & OBJECTIVE: The clinical implications of the discrepancy between cystatin C (cysC)- and serum creatinine (Scr)-estimated glomerular filtration rate (eGFR) in patients with heart failure (HF) and reduced ejection fraction (HFrEF) are unknown. STUDY DESIGN: Post-hoc analysis of randomized trial data. SETTING & PARTICIPANTS: 1,970 patients with HFrEF enrolled in PARADIGM-HF with available baseline cysC and Scr measurements. EXPOSURE: Intraindividual differences between eGFR based on cysC (eGFRcysC) and Scr (eGFRScr; eGFRdiffcysC-Scr). OUTCOMES: Clinical outcomes included the PARADIGM-HF primary end point (composite of cardiovascular [CV] mortality or HF hospitalization), CV mortality, all-cause mortality, and worsening kidney function. We also examined poor health-related quality of life (HRQoL), frailty, and worsening HF (WHF), defined as HF hospitalization, emergency department visit, or outpatient intensification of therapy between baseline and 8-month follow-up. ANALYTICAL APPROACH: Fine-Gray subdistribution hazard models and Cox proportional hazards models were used to regress clinical outcomes on baseline eGFRdiffcysC-Scr. Logistic regression was used to investigate the association of baseline eGFRdiffcysC-Scr with poor HRQoL and frailty. Linear regression models were used to assess the association of WHF with eGFRcysC, eGFRScr, and eGFRdiffcysC-Scr at 8-month follow-up. RESULTS: Baseline eGFRdiffcysC-Scr was higher than +10 and lower than-10mL/min/1.73m2 in 13.0% and 35.7% of patients, respectively. More negative values of eGFRdiffcysC-Scr were associated with worse outcomes ([sub]hazard ratio per standard deviation: PARADIGM-HF primary end point, 1.18; P=0.008; CV mortality, 1.34; P=0.001; all-cause mortality, 1.39; P<0.001; worsening kidney function, 1.31; P=0.05). For a 1-standard-deviation decrease in eGFRdiffcysC-Scr, the prevalences of poor HRQoL and frailty increased by 29% and 17%, respectively (P≤0.008). WHF was associated with a more pronounced decrease in eGFRcysC than in eGFRScr, resulting in a change in 8-month eGFRdiffcysC-Scr of-4.67mL/min/1.73m2 (P<0.001). LIMITATIONS: Lack of gold-standard assessment of kidney function. CONCLUSIONS: In patients with HFrEF, discrepancies between eGFRcysC and eGFRScr are common and are associated with clinical outcomes, HRQoL, and frailty. The decline in kidney function associated with WHF is more marked when assessed with eGFRcysC than with eGFRScr. PLAIN-LANGUAGE SUMMARY: Kidney function assessment traditionally relies on serum creatinine (Scr) to establish an estimated glomerular filtration rate (eGFR). However, this has been challenged with the introduction of an alternative marker, cystatin C (cysC). Muscle mass and nutritional status have differential effects on eGFR based on cysC (eGFRcysC) and Scr (eGFRScr). Among ambulatory patients with heart failure enrolled in PARADIGM-HF, we investigated the clinical significance of the difference between eGFRcysC and eGFRScr. More negative values (ie, eGFRScr>eGFRcysC) were associated with worse clinical outcomes (including mortality), poor quality of life, and frailty. In patients with progressive heart failure, which is characterized by muscle loss and poor nutritional status, the decline in kidney function was more pronounced when eGFR was estimated using cysC rather than Scr.

The impact of pre-existing hematologic disorders on morbidity and mortality following heart transplantation: Focus on early graft dysfunction.

BACKGROUND: Heart transplantation (HT) is the gold standard therapy for advanced heart failure, providing excellent long-term outcomes. However, postoperative outcomes are limited by bleeding, infections, and primary graft dysfunction (PGD) that contribute to early mortality after HT. HT candidates with pre-existing hematologic disorders, bleeding, and clotting, may represent a higher risk population. We assessed the short- and long-term outcomes of patients with pre-existing hematologic disorders undergoing HT. METHODS AND RESULTS: Medical records of all adult patients who received HT from January 2010 to December 2019 at our institution were retrospectively reviewed. Hematologic disorders were identified via chart review and adjudicated by a board-certified hematologist. Inverse probability weighting and multivariable models were used to adjust for potential pretransplant confounders. Four hundred and ninety HT recipients were included, of whom 29 (5.9%) had a hematologic disorder. Hematologic disorders were associated with severe PGD requiring mechanical circulatory support (aOR 3.15 [1.01-9.86]; p = .049), postoperative infections (aOR 2.93 [1.38-6.23]; p = .01), and 3-year acute cellular rejection (ACR) (≥1R/1B) (aSHR 2.06 [1.09-3.87]; p = .03). There was no difference in in-hospital mortality (aOR 1.23 [.20-7.58], p = .82) or 3-year mortality (aHR 1.58 [.49-5.12], p = .44). CONCLUSIONS: Patients with hematologic disorders undergoing HT are at increased risk of severe PGD, postoperative infections, and ACR, while in-hospital and 3-year mortality remain unaffected.

The utilization of molecular microscope in management of heart transplant recipients in the era of noninvasive monitoring.

INTRODUCTION: Monitoring for graft rejection is a fundamental tenet of post-transplant follow-up. In heart transplantation (HT) in particular, rejection has been traditionally assessed with endomyocardial biopsy (EMB). EMB has potential complications and noted limitations, including interobserver variability in interpretation. Additional tests, such as basic cardiac biomarkers, cardiac imaging, gene expression profiling (GEP) scores, donor-derived cell-free DNA (dd-cfDNA) and the novel molecular microscope diagnostic system (MMDx) have become critical tools in rejection surveillance beyond standard EMB. METHODS: This paper describes an illustrative case followed by a review of MMDx within the context of other noninvasive screening modalities for rejection. CONCLUSIONS: We suggest MMDx be used to assist with early detection of rejection in cases of discordance between EMB and other noninvasive studies.

Early post-transplant leukopenia in heart transplant recipients and its impact on outcomes.

BACKGROUND: Leukopenia in the early period following heart transplantation (HT) is not well-studied. The aim of this study was to evaluate risk factors for the development of post-transplant leukopenia and its consequences for HT recipients. METHODS: Adult patients at a large-volume transplant center who received HT between January 1, 2010 and December 31, 2020 were included. The incidence of leukopenia (WBC ≤3 × 103 /µL) in the first 90-days following HT, individual risk factors, and its effect on 1-year outcomes were evaluated. RESULTS: Of 506 HT recipients, 184 (36%) developed leukopenia within 90-days. Median duration of the first leukopenia episode was 15.5 days (IQR 8-42.5 days). Individuals who developed leukopenia had lower pre-transplant WBC counts compared to those who did not (6.1 × 103 /µL vs. 6.9 × 103 /µL, p = .02). Initial immunosuppressive and infectious chemoprophylactic regimens were not significantly different between groups. Early leukopenia was associated with a higher mortality at 1-year (6.6% vs. 2.1%, p = .008; adjusted HR 3.0) and an increased risk of recurrent episodes. Rates of infection and rejection were not significantly different between the two groups. CONCLUSIONS: Leukopenia in the early period following HT is common and associated with an increased risk of mortality. Further study is needed to identify individuals at highest risk for leukopenia prior to transplant and optimize immunosuppressive and infectious chemoprophylactic regimens for this subgroup.

Stroke and Mechanical Circulatory Support in Adults.

PURPOSE OF THE REVIEW: Short-term and durable mechanical circulatory support (MCS) devices represent life-saving interventions for patients with cardiogenic shock and end-stage heart failure. This review will cover the epidemiology, risk factors, and treatment of stroke in this patient population. RECENT FINDINGS: Short-term devices such as intra-aortic balloon pump, Impella, TandemHeart, and Venoatrial Extracorporal Membrane Oxygenation, as well as durable continuous-flow left ventricular assist devices (LVADs), improve cardiac output and blood flow to the vital organs. However, MCS use is associated with high rates of complications, including ischemic and hemorrhagic strokes which carry a high risk for death and disability. Improvements in MCS technology have reduced but not eliminated the risk of stroke. Mitigation strategies focus on careful management of anti-thrombotic therapies. While data on therapeutic options for stroke are limited, several case series reported favorable outcomes with thrombectomy for ischemic stroke patients with large vessel occlusions, as well as with reversal of anticoagulation for those with hemorrhagic stroke. Stroke in patients treated with MCS is associated with high morbidity and mortality. Preventive strategies are targeted based on the specific form of MCS. Improvements in the design of the newest generation device have reduced the risk of ischemic stroke, though hemorrhagic stroke remains a serious complication.

A Fully Magnetically Levitated Left Ventricular Assist Device - Final Report.

BACKGROUND: In two interim analyses of this trial, patients with advanced heart failure who were treated with a fully magnetically levitated centrifugal-flow left ventricular assist device were less likely to have pump thrombosis or nondisabling stroke than were patients treated with a mechanical-bearing axial-flow left ventricular assist device. METHODS: We randomly assigned patients with advanced heart failure to receive either the centrifugal-flow pump or the axial-flow pump irrespective of the intended goal of use (bridge to transplantation or destination therapy). The composite primary end point was survival at 2 years free of disabling stroke or reoperation to replace or remove a malfunctioning device. The principal secondary end point was pump replacement at 2 years. RESULTS: This final analysis included 1028 enrolled patients: 516 in the centrifugal-flow pump group and 512 in the axial-flow pump group. In the analysis of the primary end point, 397 patients (76.9%) in the centrifugal-flow pump group, as compared with 332 (64.8%) in the axial-flow pump group, remained alive and free of disabling stroke or reoperation to replace or remove a malfunctioning device at 2 years (relative risk, 0.84; 95% confidence interval [CI], 0.78 to 0.91; P<0.001 for superiority). Pump replacement was less common in the centrifugal-flow pump group than in the axial-flow pump group (12 patients [2.3%] vs. 57 patients [11.3%]; relative risk, 0.21; 95% CI, 0.11 to 0.38; P<0.001). The numbers of events per patient-year for stroke of any severity, major bleeding, and gastrointestinal hemorrhage were lower in the centrifugal-flow pump group than in the axial-flow pump group. CONCLUSIONS: Among patients with advanced heart failure, a fully magnetically levitated centrifugal-flow left ventricular assist device was associated with less frequent need for pump replacement than an axial-flow device and was superior with respect to survival free of disabling stroke or reoperation to replace or remove a malfunctioning device. (Funded by Abbott; MOMENTUM 3 ClinicalTrials.gov number, NCT02224755.).

Stroke epidemiology and outcomes in the modern era of left ventricular assist devices.

The care for the patients with end-stage heart failure has been revolutionized by the introduction of durable left ventricular assist devices, providing a substantial improvement in patient survival and quality of life and an alternative to heart transplantation. The newest devices have lower instances of mechanical dysfunction and associated pump thrombosis. Despite these improvements in complications, the use of continuous flow assist devices is still associated with high rates of thrombotic and hemorrhagic complications, most notably stroke in approximately 10% of continuous flow assist devices patients per year. With the newest HeartMate 3 devices, there have been lower observed rates of stroke, which has in part been achieved by both improvements in pump technology and knowledge of the risk factors for stroke and neurological complications. The therapeutic options available to clinicians to reduce the risk of stroke, including management of hypertension and antithrombotics, will be reviewed in this manuscript.

Letermovir for cytomegalovirus prophylaxis in high-risk heart transplant recipients.

Letermovir is a novel agent for the prevention of cytomegalovirus (CMV) infection and disease that, unlike traditional CMV DNA polymerase inhibitors, does not carry the risk of myelosuppression. The purpose of this study was to evaluate the safety, efficacy, and clinical application of letermovir for CMV prophylaxis in heart transplant (HT) recipients. Between November 1, 2019, and October 1, 2021, at a single, tertiary care hospital, 17 HT recipients were initiated on letermovir due to leukopenia while on valganciclovir. Fifteen (88%) had high-risk mismatch (CMV D+/R-). Median time on letermovir was 5 months (interquartile range, 2-8 months.) At the end of the study period, nine of 17 patients (52.9%) were still on letermovir and four of the 17 (23.5%) had successfully completed the prophylaxis window on letermovir and been switched to the pre-emptive strategy. One patient developed clinically significant CMV viremia in the setting of being unable to obtain medication due to insurance barriers but was later successfully restarted on letermovir. One patient was unable to tolerate letermovir due to symptoms of headache and myalgias. Two patients developed low-level non-clinically significant CMV viremia and were switched back to valacyclovir. All patients had tacrolimus dosages reduced at time of letermovir initiation to minimize the risk of supratherapeutic tacrolimus concentration. One patient required hospitalization due to symptomatic tacrolimus toxicity. For HT recipients who cannot tolerate valganciclovir, letermovir presents an alternative for CMV prophylaxis. Close monitoring for breakthrough CMV and calcineurin inhibitor levels is necessary. Larger studies are required to further delineate its use and help provide further evidence of its safety and efficacy.

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

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