The International Society for Heart and Lung Transplantation (ISHLT) Guidelines for the Care of Heart Transplant Recipients

The outcome of restrictive cardiac allograft physiology in severe coronary allograft vasculopathy

BACKGROUND

Microvascular dysfunction after heart transplantation leads to restrictive cardiac allograft physiology (RCP), which is classified as severe coronary allograft vasculopathy (CAV); however, the prognosis of RCP remains unclear. Therefore, in this study, we aimed to elucidate the prognosis of RCP in comparison with that of severe angiographic CAV.

METHODS

We assessed 116 patients with severe CAV who underwent heart transplantation between 2004 and 2023. RCP was defined as symptomatic heart failure with restrictive hemodynamic values (mean right atrial pressure >12 mm Hg, pulmonary capillary wedge pressure >25 mm Hg, and cardiac index <2.0 liter/min/m2). The primary outcome was death or retransplantation.

RESULTS

Of the 116 patients with severe CAV, 42 had RCP (RCP-CAV group) and 74 had severe angiographic CAV without RCP (Angio-CAV group). A significantly shorter time from heart transplantation to diagnosis and lower subsequent percutaneous catheter intervention after diagnosis were seen in the RCP-CAV group than in the Angio-CAV group (both p < 0.001). Freedom from death or retransplantation at 5 years was significantly worse in the RCP-CAV group compared to the Angio-CAV group (18.4% vs 35.4%, p = 0.001). In the Cox proportional hazard model, RCP was independently associated with an increased risk of death or retransplantation (hazard ratio 2.08, 95% confidence intervals 1.26-3.44, p = 0.004).

CONCLUSIONS

The prognosis of patients with RCP was significantly worse than that of patients with severe angiographic CAV. The early detection of microvascular dysfunction and retransplantation listing may improve the prognosis of patients with RCP.

Clinical outcomes after a biopsy diagnosis of antibody-mediated rejection in pediatric heart transplant recipients

BACKGROUND

Extending survival after heart transplant (HT) is of paramount importance for childhood recipients of HT. Acute rejection is a significant event, and biopsy remains the most specific means for distinguishing between cellular (ACR) and antibody-mediated rejection (AMR).

METHODS

All children in the Pediatric Heart Transplant Society Registry who underwent HT between January 2015 and June 2022 and had ≥1 rejection episode were included. Survival was compared between AMR and ACR-only. Secondary outcomes of infection, malignancy, and cardiac allograft vasculopathy (CAV) were assessed. Risk factors for graft loss after AMR were identified using Cox proportional hazard modeling.

RESULTS

Among 906 children with rejection, 697 (77%) with complete biopsy information were included. AMR was present on biopsy in 261 (37%) patients; ACR-only was present in 436 (63%). Time to rejection was earlier for AMR, median time from HT to rejection 0.11 versus 0.29 years, p = 0.0006. Survival after AMR in the 1st year was lower than survival after ACR-only. Predictors of graft loss after AMR were younger age at HT, congenital heart disease, and rejection with hemodynamic compromise. There was no difference in time to CAV, infection, or malignancy after rejection between groups.

CONCLUSIONS

The largest analysis of pediatric HT rejection with biopsy data to identify AMR underscores the continued importance of AMR on survival. AMR is associated with higher graft loss versus ACR when occurring in the first-year post-HT. Predictors of graft loss after AMR identify patients who may benefit from increased surveillance or augmented maintenance immunosuppression.

Can Grading of Mild Cardiac Allograft Vasculopathy be Further Refined? An angiographic and physiologic assessment of heart transplant recipients with ISHLT CAV 1

BACKGROUND

Cardiac allograft vasculopathy (CAV) results in impaired blood flow in both epicardial vessels and the microvasculature and is a leading cause of poor outcomes in heart transplant (HT) recipients. Most patients have mild (ISHLT CAV 1) disease. This study examined outcomes amongst those with ISHLT CAV 1 and investigated the value of physiologic assessment via cardiac positron emission tomography/computed tomography (PET/CT) for added risk stratification.

METHODS

CAV was graded using ISHLT criteria. Those with CAV 1 were further sub-grouped into CAV 1a (maximal lesion < 30% stenosis) or CAV 1b (maximal lesion ≥ 30% stenosis).

RESULTS

299 heart transplant recipients underwent invasive coronary angiography for CAV assessment with median follow up 4.7 years. ISHLT CAV 1 was associated with a 2.9-fold risk of death/re-transplantation compared to ISHLT CAV 0 (95% CI 1.7 -5.3, p<0.001). Of those with ISHLT CAV 1, 12% had ISHLT CAV 1b which was associated with a 2.8 times greater risk of death/re-transplantation compared to CAV 1a (95% CI 1.4-5.9, p=0.003). In a subgroup of 158 patients with contemporary cardiac PET/CT, amongst those with CAV 1a a myocardial blood flow reserve (MBFR) ≤ 2 was associated with a 4.6-fold risk of death/re-transplantation compared to a normal MBFR (95% CI 1.7-12.6, p=0.001).

CONCLUSION

Patients with ISHLT CAV 1 fared worse than those with ISHLT CAV 0. Within ISHLT CAV 1, patients with CAV 1b had worse outcomes than those with CAV 1a. Amongst those with CAV 1a, the poorer outcomes than ISHLT CAV 0 observed were predominantly associated with reduced MBFR. These data suggest additional anatomic classification and physiologic assessment can further risk stratify those with ISHLT CAV 1.

Incidence and risk factors for rejection after conversion from calcineurin inhibitor to sirolimus-based immunosuppression in orthotopic heart transplant recipients

BACKGROUND

Although recommended in International Society for Heart and Lung Transplantation (ISHLT) guidelines, transition to mammalian targets of rapamycin (mTOR) inhibitors in heart transplant recipients is not routinely performed, in part due to perceived risk of rejection. This study sought to evaluate the incidence and risk factors for biopsy-proven, clinically relevant rejection following conversion from calcineurin inhibitor (CNI) to sirolimus (SRL) immunosuppression.

METHODS

A single center retrospective study was conducted of all consecutive adult patients who underwent orthotopic heart transplantation (OHT) and CNI-free SRL conversion from January 1999 to January 2023. All post-OHT biopsy data were obtained and graded per ISHLT criteria (antibody-mediated rejection [pAMR] or acute cellular rejection [ACR]). The primary endpoint was early rejection, defined as grade 2R ACR, pAMR 1, or greater, within 6 months after conversion.

RESULTS

317 patients (72% male, mean age 51.5 ± 12.6 years) were included. Median time to SRL conversion following OHT was 0.76 years (IQR 0.49, 1.42). Median time from conversion to rejection was 0.51 years (IQR 0.31, 1.05). 38 patients (12%) experienced early rejection. Following multivariate analysis, both timing to SRL conversion following OHT (OR 0.94 per month, 95% CI: 0.89-0.99, p-value = 0.0054) and age at transplantation (OR 0.96, 95% CI: 0.93-0.99, p-value = 0.0071) were independently associated with early rejection. Rejection following SRL conversion was not associated with increased risk of cardiac allograft vasculopathy (CAV) grade 2-3.

CONCLUSIONS

In a CNI-free SRL conversion protocol, both earlier SRL conversion following OHT and younger age at transplant are independently associated with early rejection, but rejection is not associated with a net increased risk of prognostically important CAV. Individualization of transition is necessary to mitigate risk, and these findings may aid in improvement of future conversion protocols.

Veno-Arterial Extracorporeal Membrane Oxygenation (VA-ECMO) Support in New Era of Heart Transplant

Heart failure is a serious and challenging medical condition characterized by the inability of the heart to pump blood effectively, leading to reduced blood flow to organs and tissues. Several underlying causes may be linked to this, including coronary artery disease, hypertension, or previous heart attacks. Therefore, it is a chronic condition that requires ongoing management and medical attention. HF affects >64 million individuals worldwide. Heart transplantation remains the gold standard of treatment for patients with end-stage cardiomyopathy. The recruitment of marginal donors may be considered an asset at the age of cardiac donor organ shortage. Primary graft dysfunction (PGD) is becoming increasingly common in the new era of heart transplantations. PGD is the most common cause of death within 30 days of cardiac transplantation. Mechanical Circulatory Support (MCS), particularly venoarterial extracorporeal membrane oxygenation (V-A ECMO), is the only effective treatment for severe PGD. VA-ECMO support ensures organ perfusion and provides the transplanted heart with adequate rest and recovery. In the new era of heart transplantation, early use allows for increased patient survival and careful management reduces complications.

Novel Therapeutic Agents for Cardiometabolic Risk Mitigation in Heart Transplant Recipients

Heart transplant (HT) recipients experience high rates of cardiometabolic disease. Novel therapies targeting hyperlipidemia, diabetes, and obesity, including proprotein convertase subtilisin/kexin inhibitors (PCSK9i), sodium-glucose cotransporter-2 (SGLT2) inhibitors, and glucagon-like peptide-1 (GLP-1) agonists are increasingly used for cardiometabolic risk mitigation in the general population. However, limited data exist to support the use of these agents in patients who have undergone heart transplantation. Herein, we describe the mechanisms of action and emerging evidence supporting the use of novel pharmacologic agents in the post-HT setting for cardiometabolic risk mitigation and review evidence supporting their ability to modulate immune pathways associated with atherogenesis, epicardial adipose tissue (EAT), and coronary allograft vasculopathy (CAV).

Immunoproteasome inhibition reduces donor specific antibody production and cardiac allograft vasculopathy in a mouse heart transplantation model

Objective

Cardiac Allograft Vasculopathy (CAV), a process of vascular damage accelerated by antibody-mediated rejection (AMR), is one of the leading causes of cardiac transplant failure. Proteasome inhibitors (PIs) are utilized to treat AMR, however PI-associated toxicity limits their therapeutic utility. Novel immunoproteasome inhibitors (IPIs) have higher specificity for immune cells and have not been investigated for AMR in cardiac transplant patients. We sought to evaluate IPI effect on AMR in a murine cardiac transplant model.

Methods

Fully MHC mismatched C57BL/6 to huCD52Tg heterotopic heart transplantations were performed. Recipients were treated with alemtuzumab (10 µg, IP) on days -2, -1, 2, and 4 and anti-CD25mAb (PC61, 100 µg, IP) on day 7 to accelerate AMR with or without IPI (ONX-0914,15 mg/kg, SQ), administered on transplant day and three times a week thereafter.

Results

Animals without IPI gradually developed post-transplant donor-specific antibody (DSA) and showed a significantly elevated DSA level compared to animals receiving IPI. (TFXM 48.86 vs. 14.17; p = 0.0291, BFXM 43.53 vs. 6.114; p = 0.0031). Accordingly, H&E staining of allograft showed reduced evidence of AMR with IPI compared to controls (P = 0.0410). Notably, increased mortality was observed in the IPI treated group.

Conclusion

This study demonstrated the ability of ONYX-0914, an IPI, to control post-transplant DSA production and the AMR development in a heart transplant model. However, IPI-resistant DSA production was also observed and increased mortality with IPI therapy raises concerns about potential toxicity. Further investigation is warranted to assess the utility and potential risk associated with the use of IPI as a post-transplant maintenance immunosuppression.

Donor HLA-DQ reactive B cells clonally expand under chronic immunosuppression and include atypical CD21 low CD27 - B cells with high-avidity germline B-cell receptors

Long-term allograft survival is limited by humoral-associated chronic allograft rejection, suggesting inadequate constraint of humoral alloimmunity by contemporary immunosuppression. Heterogeneity in alloreactive B cells and the incomplete definition of which B cells participate in chronic rejection in immunosuppressed transplant recipients limits our ability to develop effective therapies. Using a double-fluorochrome single-HLA tetramer approach combined with single-cell in vitro culture, we investigated the B-cell receptor (BCR) repertoire characteristics, avidity, and phenotype of donor HLA-DQ reactive B cells in a transplant recipient with end-stage donor specific antibody (DSA)-associated cardiac allograft vasculopathy while receiving maintenance immunosuppression (tacrolimus, mycophenolate mofetil, prednisone). Donor DQB1*03:02/DQA1*03:01 (DQ8)-reactive IgG+ B cells were enriched for minimally mutated and germline encoded high avidity BCRs (median K D 4.26×10 -09 ) with an atypical, antigen-experienced and proliferative phenotype (CD27 - CD21 low CD71 + CD11c +/- ). These B cells coexisted with a smaller subset of more highly mutated, affinity matured IgG+CD27+ B cells. Circulating donor-reactive B cells and DSA remained detectable after rituximab, contrasting with the marked reduction in DSA after allograft explant and retransplant. Together, these findings define the persistence of germline high-avidity HLA-DQ alloreactive B cells and their co-existence with affinity matured clones that were both driven by the allograft despite conventional immunosuppression.

Emerging role of circulating piRNAs in the diagnosis of heart transplant rejection

BACKGROUND

Liquid biopsy offers a potential alternative to decrease or eliminate endomyocardial biopsy for diagnosing allograft rejection. p-element-induced wimpy testis-interacting RNAs (piRNAs) are novel and promising disease biomarkers for their intrinsic characteristics such as stability in body fluids; however, their role in allograft rejection remains unexplored.

METHODS

A training set based on small RNA sequencing technology was performed to identify piRNAs in endomyocardial tissue (n = 8) and serum samples (n = 40) from patients following heart transplantation. A validation set of the potential piRNAs identified in the training study was conducted in an independent larger cohort for the detection of acute cellular rejection (ACR, n = 105) and antibody-mediated rejection (AMR, n = 61).

RESULTS

We identified 20,292 piRNAs in endomyocardial tissue and 24,602 piRNAs in serum samples from patients following heart transplantation. We identified 7 piRNAs with a coincident expression profile in both types of samples and potential capacity for the noninvasive detection of cardiac rejection. Validation in a large independent cohort demonstrated that a panel of these piRNAs showed excellent performance for detecting grade ≥2R ACR (area under the receiver operating characteristic curve [AUC] = 0.819; p < 0.0001) and grade 1R ACR (AUC = 0.721; p = 0.001). Furthermore, our piRNA panel showed a potential discrimination ability of pAMR2 (AUC = 0.967; p < 0.0001).

CONCLUSIONS

To the best of knowledge, this study is the first to report the presence of piRNAs in both endomyocardial tissue and serum samples of patients after heart transplant, including their association with allograft rejection events. We propose a novel piRNA panel for the detection of cardiac allograft rejection.

Speckle-tracking echocardiography of left and right ventricle and acute cellular rejection in orthotropic heart transplantation: a systematic review and meta-analysis

After a cardiac transplantation, the steering of immunosuppression requires an active search for acute cellular rejection (ACR). Surveillance with endomyocardial biopsy (EMB) is the gold standard. Given the costs and potential complications, there is growing interest in the use of non-invasive screening methods. Thus, we have conducted a systematic review and meta-analysis to evaluate the role of speckle-tracking echocardiography as a screening method for ACR. We searched PubMed (CENTRAL) and gray literature for studies presenting data on speckle tracking echocardiography in heart-transplant patients experiencing acute cellular rejection. The primary outcomes of the meta-analysis were left and right ventricular global longitudinal strain. We used random effects models for all our calculations. We pre-registered our meta-analysis with PROSPERO (CRD42024508654). By incorporating data from over 2000 biopsies included in 18 studies, we found that both left (LVGLS, MD -1.96, 95% CI -2.85 to -1.07, p < 0.0001), and right (RVGLS, MD -2.90, 95% CI -4.03 to -1.76, p < 0.00001) ventricular longitudinal strain were lower among patients without ACR. The change of LVGLS from baseline over time was also greater among patients experiencing ACR (MD -2.43, 95% CI -4.82 to -0.05, p = 0.045). Current data suggest that myocardial strain measured by speckle tracking echocardiography is affected in ACR and could potentially be used for early rejection detection as a rule-out strategy, leading to reduction of routine EMB in heart transplant follow-up.

Redefining Cardiac Antibody-Mediated Rejection With Donor-Specific Antibodies and Graft Dysfunction

BACKGROUND

Heart transplant recipients with donor-specific antibodies (DSAs) have an increased risk for antibody-mediated rejection. However, many patients with graft dysfunction and DSA do not have evidence of antibody-mediated rejection by endomyocardial biopsy (EMB).

METHODS

Participants from this prospective, multicenter study underwent serial EMB, echocardiogram, DSA, and donor-derived cell-free DNA evaluations. Outcomes were defined as pAMR+ (pAMR≥1) or DSA+/left ventricle (LV) dysfunction (DSA presence+LVEF drop ≥10% to an LVEF≤50%). Cox regression evaluated the association between antibody-mediated rejection categories and death or sustained (for 3 months) reduction of LVEF to <50%.

RESULTS

Two hundred sixteen patients (29% women, 39% Black race, median age 55 [interquartile range, 47-62] years) had 1488 EMB, 2792 DSA, 1821 echocardiograms, and 1190 donor-derived cell-free DNA evaluations. DSAs were present in 86 patients (40%). Fourteen patients had isolated pAMR+ episodes and 8 patients had isolated DSA+/LV dysfunction episodes; 2 patients had pAMR+ and then subsequently DSA+/LV dysfunction with pAMR+. Median %dd-cfDNA was significantly higher at diagnosis of pAMR+ (0.63% [interquartile range, 0.23-2.0]; P=0.0002), or DSA+/LV dysfunction (0.40% [interquartile range, 0.36-1.24]; P<0.0001), compared with patients without these outcomes (0.01% [interquartile range, 0.0001-0.10]). Both pAMR+ and DSA+/LV dysfunction were associated with long-term clinical outcome of death (n=18) or prolonged LV dysfunction (n=10): pAMR+ (hazard ratio, 2.8 [95% CI, 1.03-7.4]; P=0.043); DSA+/LV dysfunction (hazard ratio, 26.2 [95% CI, 9.6-71.3]; P<0.001); composite of both definitions (hazard ratio, 6.5 [95% CI, 2.9-14.3]; P<0.001). Patients who developed pAMR+ or DSA+/LV dysfunction within the first 6 months of transplant were more likely to die within 3 years posttransplant (hazard ratio, 3.9 [95% CI, 1.03-14.6]; P=0.031).

CONCLUSIONS

Expanding the characterization of antibody-mediated rejection to include patients with DSA and concurrent allograft dysfunction identified DSA+ patients at risk for death and prolonged LV dysfunction.

Kidney function assessment using cystatin C and serum creatinine in heart transplantation recipients: Implications for valganciclovir dosing

BACKGROUND

Among heart transplantation (HT) recipients, the accuracy of serum creatinine (sCr)-based estimated glomerular filtration rate (eGFR) may be limited by fluctuations in muscle mass. Cystatin C (cysC) is less influenced by muscle mass, but its levels may increase with obesity and steroid use. Herein, we (1) longitudinally compared eGFRcysC and eGFRsCr among HT recipients; (2) investigated the association of body mass index (BMI), steroid use, and muscle mass with discrepancies between eGFRs; and (3) explored the implications of eGFRcysC use on valganciclovir (VGC) dosing.

METHODS

cysC and sCr were measured in 294 blood samples obtained from 80 subjects. Intraindividual differences between eGFRs (eGFRdiffcysC-sCr) were calculated with negative values corresponding to eGFRsCr > eGFRcysC and positive values to eGFRcysC > eGFRsCr. In a patient subset (n = 21), pectoralis muscle measures were obtained.

RESULTS

Marked differences between eGFRcysC and eGFRsCr were observed, particularly early post-HT (1-week post-HT, median eGFRdiffcysC-sCr -28 ml/min/1.73 m2). eGFRcysC demonstrated stability following a transient postoperative decline, while eGFRsCr decreased in the first year post-HT. Lower BMI and higher prednisone dose displayed a modest association with more negative eGFRdiffcysC-sCr values. Pectoralis muscle measures indicative of greater muscle mass and better tissue quality exhibited a stronger association with more positive eGFRdiffcysC-sCr values. The use of eGFRcysC would have led to VGC dose adjustment in 46% of samples, predominantly resulting in dose reduction.

CONCLUSIONS

Among HT recipients, eGFRcysC and eGFRsCr markedly differ with implications for VGC dosing. The observed discrepancies may reflect changes in body composition and steroid use.

Optimizing Outcomes in Heart Transplantation: The Role of High-Intensity Statin Therapy

Heart transplantation is a vital procedure for patients with end-stage heart failure, but it faces significant challenges, including graft dysfunction, rejection, and cardiac allograft vasculopathy (CAV), which can compromise long-term graft success. Research suggests that statin therapy may offer significant benefits to heart transplant recipients, such as improved long-term survival and reduced rates of graft rejection and mortality. The aim of this review is to thoroughly examine the recent literature on this topic since 2005. Early use of high-dose statins appears to be particularly effective in preventing vasculopathy and improving outcomes, although a titrated approach may help to reduce side effects. High-dose statins may provide superior cardiovascular benefits, including lower rates of CVD, slower progression of CVD and improved long-term graft survival. Despite potential concerns about adverse effects, evidence suggests that high-intensity statins improve cholesterol levels without increasing serious adverse events after transplantation. The goal of statin therapy in heart transplant recipients is to balance the well-established benefits seen in the general population with the specific needs of this group, with the ultimate goal of improving both longevity and quality of life.

Usefulness of biomarkers to predict prognosis after heart transplant

INTRODUCTION AND OBJECTIVES

Heart transplant (HT) represents a major physiological stress, resulting in elevated levels of analytical biomarkers. This study aimed to determine whether changes in biomarker levels after HT can identify patients with a poor prognosis.

METHODS

A prospective longitudinal noninterventional study was conducted in 149 consecutive patients undergoing HT from July 2017 to July 2023. Biomarkers were assessed before HT and at 6, 24, 48, 72, and 96hours after HT. The biomarkers analyzed were high-sensitivity troponin T, N-terminal pro-B-type natriuretic peptide (NT-proBNP), creatinine, and lactic acid. The primary outcome was a composite of death and severe primary graft failure (PGF).

RESULTS

NT-proBNP and troponin levels remained highly elevated throughout the period and stabilized from the first 24hours post-HT. Lactate levels stabilized after the first 24hours, and creatinine from the second day onward. Exitus occurred in 23 (15%) of the patients, and severe PGF in 26 (17%). All biomarkers were significantly associated with the incidence of the combined event (P <.0001). Receiver operating characteristic curve analysis at 24hours showed significant areas under the curve (P=.0001). The greatest discriminatory power was observed for the NT-proBNP curve. A value of 10 000 pg/mL had a sensitivity of 90% and specificity of 80%.

CONCLUSIONS

A significant elevation of post-HT analytical biomarkers was associated with mortality and/or severe PGF. Among the biomarkers analyzed, NT-proBNP was the most accurate in classifying patients.

Assessing the cost-effectiveness of replacing antimetabolites with mTOR inhibitors in heart transplant immunosuppression in China: a network meta-analysis-based economic evaluation

BACKGROUND

Although several pharmacoeconomic studies have assessed the cost-effectiveness of maintenance immunosuppressive regimens for heart transplant recipients, economic comparisons between various combination drug therapies remain sparse.

AIM

This study used an economic evaluation based on network meta-analysis to assess the cost-effectiveness of four immunosuppressive regimens for adult heart transplant recipients in China.

METHOD

We conducted a systematic search for clinical trials in PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Data, and VIP database. A validated Markov model was adapted to reflect the Chinese medical landscape. Four maintenance immunosuppression regimens were considered: tacrolimus/mycophenolate mofetil (TAC/MMF), cyclosporine/mycophenolate mofetil (CSA/MMF), everolimus/cyclosporine (EVL/CSA), and sirolimus/tacrolimus (SRL/TAC). The probabilities of health events were derived from a comprehensive literature review. Direct medical costs, adjusted for 2022 values, were from public documents and websites, while utilities for quality-adjusted life-years (QALYs) were taken from previous studies. Primary outcomes were mean lifetime cost, QALYs, and cost-effectiveness, with a willingness-to-pay (WTP) threshold set at three times China's GDP per capita in 2022. Sensitivity analyses were conducted to test the robustness of the results.

RESULTS

The base case analysis identified TAC/MMF as the most cost-effective regimen, producing a mean of 6.31 QALYs per patient at a cost of Chinese Yuan (CNY) 534,182.89. Sensitivity analyses consistently reinforced TAC/MMF as the most cost-effective and robust choice.

CONCLUSION

TAC/MMF is the most cost-effective maintenance immunosuppressive regimen for heart transplant recipients within the Chinese health system. The study findings are reinforced by sensitivity analyses, affirming their robustness amid various uncertainties.

Progress of Angiographic Cardiac Allograft Vasculopathy in Patients With Long-Term Transplantation: Longitudinal Evaluation of Its Association With Dyslipidemia Patterns

Cardiac allograft vasculopathy (CAV) is a progressive disease with limited options for secondary prevention. Ways to manage lipid parameters and dyslipidemia patterns in care after transplantation remain unclear. In this longitudinal study, we included 32 patients with long-term heart transplantations (median interval after transplant 13.8 years) with angiographic manifest CAV. In 299 matched nonstented segments at 3 distinct time points ([TPs] 0 to 2, with median intervals of 2 years, respectively), progress of diameter stenosis (Δ%DS) defined CAV progress. Values above the median of maximal Δ%DS defined substantial CAV progress. Category of left ventricular ejection fraction was evaluated at TP0 and TP3 (2 years after TP2). Findings were correlated with dyslipidemia patterns at TP0, and lipid variations at follow-up (TP1 to TP3). Analyses included routine lipid assessment, and triglycerides/high-density lipoprotein-cholesterol ratio (TG/HDL-c) and atherogenic index of plasma (AIP). At TP1 and TP2, patients with increase of TG/HDL-c ≥0.1 (p = 0.02, respectively) and with increase of AIP (p = 0.01 and p = 0.049, respectively) presented a greater maximal Δ%DS. Dyslipidemia patterns at TP0 did not show a relevant association with CAV progress. At TP2, increase of TGs, TG/HDL-c, and AIP were associated with substantial CAV progress (odds ratio [OR] 5.0, p = 0.046, and OR 9.2, p = 0.01, OR 6.6, p = 0.02, respectively). At TP3, patients with CAV-related worsening of left ventricular ejection fraction category presented with a greater increase of TG/HDL-c (p = 0.03). Although findings at TP0 did not affect CAV progress, an increase of TG/HDL-c could define patients at greater risk of CAV progress and CAV-related deterioration of graft function.

Useful central mechanical circulatory support system for critical biventricular heart failure associated with high pulmonary vascular resistance

BACKGROUND

Peripheral veno-arterial extracorporeal membrane oxygenation (ECMO) is a powerful life-saving tool; however, it can sometimes induce severe pulmonary edema in patients with critical heart failure. We report favorable outcomes in critically ill patients by using a central ECMO system with an innovative blood perfusion method.

METHODS

We analyzed 10 patients with severe heart failure and pulmonary edema who were treated with the central ECMO system at our institution between April 2022 and October 2023. The system consists of central cannulation with two inflows from the right atrium and left ventricle, and two outflows to the aorta and pulmonary artery, connected by two Y-connectors to a single ECMO circuit (RALV-AOPA ECMO). In this system, blood flow to the pulmonary artery is adjusted and mean pulmonary artery pressure is limited to <20 mm Hg, which reduces right ventricular afterload and prevents the worsening of pulmonary edema and hemorrhage.

RESULTS

Six patients were diagnosed with fulminant lymphocytic myocarditis, and four were diagnosed with coronavirus disease 2019-related myocardial injury. The ejection fraction was 6.5 ± 4.1%. The average intraoperative pulmonary vascular resistance was 4.6 ± 1.3 Wood units. After 24 h, the mean pulmonary arterial pressure was 12.8 ± 4.3 mm Hg, and pulmonary vascular resistance was 1.5 ± 0.3 Wood units. The duration of central RALV-AOPA ECMO was 3.7 ± 2.1 days. Finally, six patients were weaned, three received HeartMate3, and one received heart transplantation. At follow-up, all patients remained alive (428 ± 208 days), and two patients experienced cerebrovascular accidents without any lasting sequelae.

CONCLUSIONS

The central RALV-AOPA ECMO is an innovative system that achieves early improvement in pulmonary vascular resistance and is safe and feasible for patients with acute biventricular failure and pulmonary edema.

Donor-derived cell-free DNA as a new biomarker for cardiac allograft rejection: A prospective study (FreeDNA-CAR)

BACKGROUND

There is a long-standing need for a noninvasive biomarker that allows monitoring of cardiac allograft rejection, avoiding the need for periodic endomyocardial biopsies (EMB).

METHODS

Multicenter, observational, prospective study, performed between 2019 and 2023 (NCT04973943). All patients underwent 7 per-protocol surveillance EMB during the first postheart transplantation year. Donor-derived cell-free DNA (dd-cfDNA) levels were determined before each EMB, using Next Generation Sequencing Technology (Allonext assay, Eurofins Genome). The primary end-point was the association between dd-cfDNA levels and the presence of acute cellular rejection (ACR) in EMB.

RESULTS

The study included 206 patients from 12 centers, with 1,090 pairs of EMB/dd-cfDNA determinations available for analysis. EMB with ACR (n = 49) were associated with dd-cfDNA levels significantly higher than those without, median 0.189% (interquartilic range 0.05-0.70) vs 0.095% (0.04-0.23), p = 0.013. A dd-cfDNA threshold of 0.10% showed a negative predictive value for ACR of 97%. A statistically significant association between N-terminal prohormone of brain (NTProBNP) and dd-cfDNA was also found, with an increase of 0.007% dd-cfDNA (95% confidence interval 0.003-0.011) for every 500 units of NTproBNP, p 0.001. The combination of both biomarkers for diagnosis of ACR showed an area under the receiver operating characteristic (ROC) curve of 0.681, and this combined approach was significantly better than dd-cfDNA alone (area under the ROC curve 0.603), p = 0.016. Using a cut-off point of 0.10% for dd-cfDNA and 1,000 UI/ml for NTproBNP, negative predictive value increased to 98.1%.

CONCLUSIONS

dd-cfDNA may be a useful biomarker to rule out significant ACR in a low-risk population. However, a dd-cfDNA value above normal threshold does not correlate robustly with the presence of disease. The combination with NTproBNP, a readily available biomarker, increased the discrimination power of dd-cfDNA alone.

CLINICAL TRIAL NOTATION

Donor-derived Cell-Free DNA as a New Biomarker in Cardiac Acute Rejection, NCT04973943.

Therapeutic plasma exchange is associated with increased survival in heart transplant recipients experiencing severe primary graft dysfunction

BACKGROUND

Primary graft dysfunction (PGD) remains the leading cause of 30-day mortality post-heart transplantation (HTx). HTx recipients experiencing severe PGD have been found to have high levels of circulating proteins associated with PGD occurrence and post-HTx survival. Whether treating these patients with therapeutic plasma exchange (TPE) can attenuate ongoing immunological and inflammatory processes and improve post-transplant outcomes has not been well-investigated. Therefore, we aim to examine the impact of treatment with TPE on 30-day and 1-year clinical outcomes of patients experiencing severe PGD post-HTx.

METHODS

Between 2010 and 2022, we included 42 HTx patients who developed severe PGD. All included patients were placed on veno-arterial extracorporeal membrane oxygenation. We divided these patients into those who received TPE and those who did not (by physician choice). Endpoints included 30-day and 1-year survival, as well as 1-year-freedom from Any-treated rejection (ATR), acute cellular rejection (ACR), antibody-mediated rejection (AMR), biopsy negative rejection (BNR), cardiac allograft vasculopathy (CAV), non-fatal major adverse cardiac events (NF-MACE), and freedom from left ventricular dysfunction (LVD) at 1-year post-HTx.

RESULTS

Compared to patients who did not receive TPE, those managed with TPE had increased survival rates at 30 days (78.1% vs. 40%, p = 0.007) and at 1-year post-HTx (56.25% vs. 30% p = 0.035). However, no statistically significant differences were recorded in other outcomes of interest, including 1-year freedom from CAV, ATR, ACR, AMR, BNR, NF-MACE, or LVD.

CONCLUSION

TPE may serve as a promising therapeutic approach in HTx recipients experiencing severe PGD.

Repeated CXCR4 Blockade by Plerixafor Attenuates Transplant Vasculopathy in Murine Aortic Allografts

Plerixafor, a hematopoietic stem cell mobilization agent, increases the peripheral blood content of effector and regulatory T cells and may have beneficial effects on cardiac allograft vasculopathy. The aim of the current study was to evaluate its effects in a murine aortic allograft model using different application procedures. Allogeneic donor aorta grafts (n = 8/group) from C57BL/6 mice(H2b) were abdominally transplanted into CBA mice (H2k). Plerixafor application was performed either continuously for 14 d using abdominally implanted osmotic pumps (1 mg/kg/d) or i.p. with a single dose (1 and 5 mg/kg) on day 0 or pulsed injections of 1 mg/kg on days 0, 7, 14, and 21. Cell distribution was monitored by FACS. Aortic grafts were evaluated for neointima development by Elastica-van-Gieson on day 30. Immunofluorescence and intragraft gene expression analysis were performed. On day 14, significantly fewer hematopoietic stem cells were found in the bone marrow of all plerixafor-treated mice. In the pulsed application group, significantly more hematopoietic stem cells were found in the peripheral blood on day 14 (0.045 ± 0.002%; p < 0.01 [pulsed]; versus 0.0068 ± 0.002% [control]) and also more regulatory T cells. PCR revealed lower inflammatory cytokines. The luminal occlusion was significantly reduced in the pulsed treated group (33.65 ± 8.84 versus 53.13 ± 12.41) going along with decreased neointimal CD4+ T cell and plasmacytoid dendritic cell infiltration, as well as less smooth muscle cell proliferation. The application of plerixafor attenuates chronic rejection in aortic allografts via immunomodulatory effects. Injection of repeated low-dose plerixafor is the most effective application form in the aortic transplant model.

Donor Selection for Heart Transplantation in 2024

The number of candidates on the waiting list for heart transplantation (HT) continues to far outweigh the number of available organs, and the donor heart nonuse rate in the United States remains significantly higher than that of other regions such as Europe. Although predicting outcomes in HT remains challenging, our overall understanding of the factors that play a role in post-HT outcomes continues to grow. We observe that many donor risk factors that are deemed "high-risk" do not necessarily always adversely affect post-HT outcomes, but are in fact nuanced and interact with other donor and recipient risk factors. The field of HT continues to evolve, with ongoing development of technologies for organ preservation during transport, expansion of the practice of donation after circulatory death, and proposed changes to organ allocation policy. As such, the field must continue to refine its processes for donor selection and risk prediction in HT.

2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery" provides recommendations to guide clinicians in the perioperative cardiovascular evaluation and management of adult patients undergoing noncardiac surgery.

METHODS

A comprehensive literature search was conducted from August 2022 to March 2023 to identify clinical studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

Recommendations from the "2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery" have been updated with new evidence consolidated to guide clinicians; clinicians should be advised this guideline supersedes the previously published 2014 guideline. In addition, evidence-based management strategies, including pharmacological therapies, perioperative monitoring, and devices, for cardiovascular disease and associated medical conditions, have been developed.

Longitudinal Assessment of T1 Mapping Trends Disease in Pediatric Patients With Heart Transplant

BACKGROUND

Surveillance for heart transplant rejection by endomyocardial biopsy is invasive and may yield false negatives. T1 and T2 mapping from cardiac magnetic resonance can demonstrate elevations with rejection. We sought to evaluate longitudinal changes in T1 and T2 mapping in pediatric patients with heart transplant.

METHODS AND RESULTS

A cohort study was performed of pediatric patients with heart transplant who underwent concurrent endomyocardial biopsy and cardiac magnetic resonance with T1 and T2 mapping from December 2019 to July 2024. Segmental values were measured and subsegmental elevations (ie, hotspots) were identified. Subjects were categorized as either treated rejection or no rejection. Peak and mean T1 and T2 values and number of hotspots at/between each time point for patient dyads were compared between the groups. A total of 21 subjects (7 treated rejection, 14 no rejection) with 68 total encounters met inclusion criteria. Peak and mean T1 values were higher in treated rejection patients during the rejection period and decreased with treatment (peak, 1086 versus 1052; mean, 1028 versus 1021), such that at last follow-up when their rejection had resolved, there was no significant difference in values when compared with no rejection patients (peak, 1066; mean, 1016). The number of T1 hotspots decreased after rejection treatment (2 versus 1). There were no changes in peak or mean T2 values in the treated rejection group despite treatment, and peak and mean T2 values were similar to patients with no rejection through last follow-up.

CONCLUSIONS

Elevated T1 values and hotspots observed during cardiac allograft rejection decline in response to treatment. Cardiac magnetic resonance may serve as a noninvasive monitoring tool for the development and resolution of rejection, as well as the effectiveness of rejection therapy.

2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery" provides recommendations to guide clinicians in the perioperative cardiovascular evaluation and management of adult patients undergoing noncardiac surgery.

METHODS

A comprehensive literature search was conducted from August 2022 to March 2023 to identify clinical studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

Recommendations from the "2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery" have been updated with new evidence consolidated to guide clinicians; clinicians should be advised this guideline supersedes the previously published 2014 guideline. In addition, evidence-based management strategies, including pharmacological therapies, perioperative monitoring, and devices, for cardiovascular disease and associated medical conditions, have been developed.

Donor age and ischemic time in heart transplantation - implications for organ preservation

BACKGROUND

The Organ Care System and Non-ischemic Heart Preservation methods have emerged as significant advancements in heart transplantation, designed to mitigate ischemic injury and extend preservation times. However, their high costs and logistical complexities necessitate strategic utilization.

METHODS

We evaluated data from 83,761 heart transplants registered in the International Society for Heart and Lung Transplantation registry from 1988 to 2018. Utilizing a Cox proportional hazards model, we explored the influence of donor age and ischemic time on transplant survival. A key innovation of our study is the development of a nomogram to predict post-transplant survival, incorporating both traditional and advanced statistical methods.

RESULTS

The median age of recipients was 52 years (22% female) and 33 years (31% female) for donors. Analysis revealed a median ischemic time of 3 hours and median survival of 11.5 years across the cohort. The nomogram showed a decline in survival probabilities with increasing donor age, notably from age 40 and more significantly with ischemic times >4 hours. Ischemic times ≥4 hours versus <2 hours were associated with hazard ratio (HR) of 1.2 (95% CI, 1.1-1.3) for donors aged 40-59, a disparity that escalated for donors aged ≥60 (HR: 2.0; 95% CI, 1.5-2.7).

CONCLUSIONS

This study highlights the importance of careful donor selection and indicates that certain groups, particularly older donors with prolonged ischemic times, might benefit from ex-vivo preservation techniques. The developed nomogram offers a practical tool for clinicians, enhancing decision-making by providing detailed insights into the relationship between donor age, ischemic time, and post-transplant mortality.

Terbutaline for Management of Relative Bradycardia Post-Orthotopic Heart Transplant: A Single Center Experience

BACKGROUND

Vagal nerve denervation during the heart transplant procedure results in higher resting heart rates in these recipients compared to the general population. Relative bradycardia (RB) is a common and often temporary post-operative complication that can be managed with agents like terbutaline; however, little data exist on the efficacy, safety, and necessity of long-term terbutaline use post-heart transplant.

METHODS

This was a single-center, retrospective, descriptive study conducted at a large academic medical center investigating oral terbutaline use for RB management in heart transplant recipients. Outcomes included time to and reason for terbutaline discontinuation post-transplant, adverse event rates, and permanent pacemaker (PPM) placement rates.

RESULTS

In the 229 patients included, the median (IQR) time to terbutaline initiation was 8 (5, 12) days post-heart transplant, with a median (IQR) time to discontinuation of 56 (20, 96) days from the first dose. In most cases, terbutaline was successfully tapered off outpatient due to the resolution of RB. Tachyarrhythmias occurred in 29 (12.7%) patients without long-term sequelae. At 3 months post-transplant, PPM had been placed for chronotropic support in 15 patients (6.6%) with a median time (IQR) to PPM placement of 24 (19, 77) days from transplant.

CONCLUSION

This study's overall low PPM placement rate suggests that early sinus node dysfunction can be treated with pharmacotherapy without committing to a permanent device, and that terbutaline can be used safely in early post-heart transplant recipients. If patients require long-term chronotropic support, the risk-benefit of PPM placement versus continued terbutaline should be considered.

The dual prevalence of advanced degrees of obesity and heart failure: a study from the National Inpatient Sample database

BACKGROUND

National prevalence rates for obesity and heart failure (HF) have been steadily increasing, which predisposes patients to higher morbidity and mortality rates.

OBJECTIVES

The purpose of this study was to evaluate the prevalence of HF stages in hospitalized patients according to their body mass index (BMI).

SETTING

Academic institution.

METHODS

National Inpatient Sample data from 2016 to 2018 were examined to identify patients with obesity, HF (presence or absence of advanced HF [AHF]), and cardiogenic shock (CS). The proportion of hospital admissions was determined for each category on the basis of the presence of AHF with/without CS. A comparative analysis was performed between patients with and without AHF, and multivariate logistic regression analysis was performed for the event of AHF. The same analyses were performed for the event of CS.

RESULTS

A total of 3,354,970 hospital admissions were identified. The prevalence of hospital admissions with a diagnosis of AHF and class III obesity and a diagnosis of CS and class III obesity was 21% and .5%, respectively. The prevalence of AHF and other classes of BMI and CS and other classes of BMI was 17% and .5%, respectively. The univariate analysis showed that there were significant variations in 10 factors between hospital admissions with/without the diagnosis of both AHF and CS. Statistical analyses indicated the following findings: Hospitalized patients in higher obesity groups are more likely to have AHF, and they are less likely to have CS compared with those with a BMI of ≤29.9.

CONCLUSIONS

This study revealed that the prevalence of AHF was significantly higher in hospitalized patients with class III obesity. These findings have implications for clinical management, and it can be inferred that these patients are less likely to receive advanced cardiac replacement therapies and might benefit from innovative approaches to address severe dual morbidity.

The Effect of Everolimus Versus Calcineurin Inhibitors on Quality of Life 10-12 Years After Heart Transplantation: The Results of a Randomized Controlled Trial (SCHEDULE Trial)

BACKGROUND

Calcineurin inhibitors (CNIs) are associated with long-term complications after heart transplantation (HTx). Everolimus (EVR)-based immunosuppression allows for CNI withdrawal. We used data from The Scandinavian heart transplant everolimus de novo study with early CNI avoidance (SCHEDULE) trial to assess whether health-related quality of life (HRQoL) differed between patients on long-term treatment with EVR versus a CNI-based regimen.

METHODS

In SCHEDULE, we randomized 115 patients (mean age 51 ± 13 years, 27% women) to cyclosporine (CNI group; n = 59), or early introduction of EVR and cyclosporine withdrawal within 11 weeks of HTx (EVR group; n = 56). The primary endpoint was the glomerular filtration rate. We used the Short Form-36 (SF-36v2), the EuroQoL visual analogue scale (EQ VAS), and the Beck Depression Inventory (BDI) to assess HRQoL. We re-evaluated the participants after 10-12 years.

RESULTS

Seventy-eight patients attended follow-up at a median of 11 years after HTx. The SF-36 physical component summary score increased from 32 ± 10 pre-HTx to 44 ± 12 11 years after HTx (p < 0.01) in the EVR group and from 33 ± 9 to 44 ± 11 (p < 0.01) with CNI. The mental component summary score increased from 46 ± 12 to 53 ± 13 (EVR); p = 0.04 and from 38 ± 13 to 49 ± 13 (CNI); p < 0.01. Similar improvements were observed regarding EQ-VAS and the BDI. There were no significant between-group differences for either measure of HRQoL.

CONCLUSIONS

In heart transplant recipients, an EVR-based immunosuppressive strategy resulted in similar long-term improvements in HRQoL as treatment with a CNI-based regimen.

Pulmonary hypertension associated to left heart disease: Phenotypes and treatment

Pulmonary hypertension associated to left heart disease (PH-LHD) refers to a clinical and haemodynamic condition of pulmonary hypertension associated with a heterogeneous group of diseases affecting any of the compartments that form the left ventricle and left atrium. PH-LHD is the most common cause of PH, accounting for 65-80 % of diagnoses. Based on the haemodynamic phase of the disease, PH-LDH is classified into three subgroups: postcapillary PH, isolated postcapillary PH and combined pre-postcapillary PH (CpcPH). Several signaling pathways involved in the regulation of vascular tone are dysfunctional in PH-LHD, including nitric oxide, MAP kinase and endothelin-1 pathways. These pathways are the same as those altered in PH group 1, however PH-LHD can heardly be treated by specific drugs that act on the pulmonary circulation. In this manuscript we provide a state of the art of the available clinical trials investigating the safety and efficacy of PAH-specific drugs, as well as drugs active in patients with heart failure and PH-LHD. We also discuss the different phenotypes of PH-LHD, as well as molecular targets and signaling pathways potentially involved in the pathophysiology of the disease. Finally we will mention some new emerging therapies that can be used to treat this form of PH.

Right Ventricular Mass Oversizing Is Associated With Improved Post-transplant Survival in Heart Transplant Recipients With Elevated Transpulmonary Gradient

BACKGROUND

This study evaluates the effects of pre-transplant transpulmonary gradient (TPG) and donor right ventricular mass (RVM) on outcomes following heart transplantation.

METHODS

UNOS registry was queried to analyze adult recipients who underwent primary isolated heart transplantation from 1/1/2010 to 12/31/2018. The recipients were dichotomized into 2 groups based on their TPG at the time of transplantation, < 12 and ≥ 12 mmHg. The outcomes included 5-year survival and post-transplant complications. Propensity score-matching was performed. Subanalysis was performed to evaluate the effects of donor-recipient RVM matching, where a ratio < 0.85 was classified as undersized, 0.85-1.15 as size-matched, and > 1.15 as oversized.

RESULTS

We analyzed 17,898 isolated heart transplant recipients, and 5129 (28.7%) recipients had TPG ≥ 12 mmHg at the time of transplantation. The recipients with TPG ≥ 12 mmHg experienced significantly lower 5-year survival rates (78.4% vs 81.2%; P < 0.001) compared to the recipients with TPG < 12 mmHg, and this finding persisted in the propensity score-matched comparison. The recipients with TPG ≥ 12 mmHg experienced a higher rate of post-transplant dialysis and a longer duration of hospitalization. Oversizing the donor RVM considerably improved the 5-year survival among the recipients with TPG ≥ 12 mmHg, comparable to those with TPG < 12 mmHg.

CONCLUSION

Elevated pre-transplant TPG is associated with significantly reduced post-transplant survival. However, oversizing the donor RVM is associated with improved survival rates in recipients with elevated TPG, resulting in improved survival that is comparable to that of recipients with normal TPG. Therefore, careful risk stratification and donor matching among recipients with elevated TPG is essential to improve outcomes in this vulnerable population.

Management of heart disease in renal transplant recipients: a national Delphi survey-based SET/SEC/SEN consensus document

Renal transplantation improves the survival and quality of life of patients with end-stage renal disease. Cardiovascular disease is the leading cause of morbidity and mortality in renal transplant recipients. The bidirectional relationship between renal and heart disease creates a unique clinical scenario that demands a comprehensive and personalized approach. This expert consensus, drafted by the Spanish Society of Transplantation, the Spanish Society of Cardiology, and the Spanish Society of Nephrology, aims to assess current practices and propose strategies for the management of heart disease in renal transplant recipients. A panel of Spanish nephrologists and cardiologists with expertise in renal and heart transplantation reviewed the scientific evidence concerning the current management of heart disease in renal transplant recipients. Subsequently, consensus statements were created through a 2-round Delphi methodology, resulting in 30 statements covering key topics such as the identification of renal transplant candidates, the management of heart disease in renal transplant recipients, and eligibility for combined heart-kidney transplantation in patients with both end-stage renal disease and cardiac disease. These consensus statements provide expert guidance for the management of heart disease in renal transplant recipients, an area where published clinical evidence remains limited.

Evaluation and Management of Kidney Dysfunction in Advanced Heart Failure: A Scientific Statement From the American Heart Association

Early identification of kidney dysfunction in patients with advanced heart failure is crucial for timely interventions. In addition to elevations in serum creatinine, kidney dysfunction encompasses inadequate maintenance of sodium and volume homeostasis, retention of uremic solutes, and disrupted endocrine functions. Hemodynamic derangements and maladaptive neurohormonal upregulations contribute to fluctuations in kidney indices and electrolytes that may recover with guideline-directed medical therapy. Quantifying the extent of underlying irreversible intrinsic kidney disease is crucial in predicting whether optimization of congestion and guideline-directed medical therapy can stabilize kidney function. This scientific statement focuses on clinical management of patients experiencing kidney dysfunction through the trajectory of advanced heart failure, with specific focus on (1) the conceptual framework for appropriate evaluation of kidney dysfunction within the context of clinical trajectories in advanced heart failure, including in the consideration of advanced heart failure therapies; (2) preoperative, perioperative, and postoperative approaches to evaluation and management of kidney disease for advanced surgical therapies (durable left ventricular assist device/heart transplantation) and kidney replacement therapies; and (3) the key concepts in palliative care and decision-making processes unique to individuals with concomitant advanced heart failure and kidney disease.

Single center experience with ABO-incompatible and ABO-compatible pediatric heart transplantation

Introduction

The aim of this study was to analyze the results after pediatric heart transplantation (pHTx) at our single center differentiating between ABO-incompatible (ABOi) and -compatible (ABOc) procedures.

Methods and patients

We retrospectively analyzed outcomes of ABO-incompatible HTx procedures performed at our center and compared the data to ABO-compatible HTx of the same era. Eighteen children (<17 months) underwent pediatric HTx and seven of them underwent ABO-incompatible HTx between 2003 and 2015.

Results

Mechanical circulatory support as bridge to transplant was necessary in 3/7 patients before ABO-incompatible HTx and in 3/11 patients before ABO-compatible HTx. Mean waiting time on the list was 36 ± 30 days for ABO-incompatible HTx and 86 ± 65 days for ABO-compatible HTx. The 5-years re-transplant free survival was 86% following ABO-incompatible and 91% after ABO-compatible. In the cohort undergoing ABO-incompatible HTx, 2 patients showed an acute cellular rejection, while early graft failure was not observed. In the cohort undergoing ABOcompatible HTx, acute cellular rejection was observed in 9/11 patients, with early graft failure occurring in nine and CVP in two. A total of ten children were listed for ABO-incompatible HTx after 2015; however, all ten underwent an ABO-compatible transplantation.

Discussion

This study adds much needed information to the literature on ABOi-HTx by showing with a retrospective single center analysis that it is safe and leads to shorter waiting times. We conclude that strategies for ABOi-HTx should be elaborated further, potentially allowing more timely transplantation and thereby preventing waiting list complications such as the need for mechanical circulatory support and even death.

International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024

The "International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024" updates and replaces the "Listing Criteria for Heart Transplantation: International Society for Heart and Lung Transplantation Guidelines for the Care of Cardiac Transplant Candidates-2006" and the "2016 International Society for Heart Lung Transplantation Listing Criteria for Heart Transplantation: A 10-year Update." The document aims to provide tools to help integrate the numerous variables involved in evaluating patients for transplantation, emphasizing updating the collaborative treatment while waiting for a transplant. There have been significant practice-changing developments in the care of heart transplant recipients since the publication of the International Society for Heart and Lung Transplantation (ISHLT) guidelines in 2006 and the 10-year update in 2016. The changes pertain to 3 aspects of heart transplantation: (1) patient selection criteria, (2) care of selected patient populations, and (3) durable mechanical support. To address these issues, 3 task forces were assembled. Each task force was cochaired by a pediatric heart transplant physician with the specific mandate to highlight issues unique to the pediatric heart transplant population and ensure their adequate representation. This guideline was harmonized with other ISHLT guidelines published through November 2023. The 2024 ISHLT guidelines for the evaluation and care of cardiac transplant candidates provide recommendations based on contemporary scientific evidence and patient management flow diagrams. The American College of Cardiology and American Heart Association modular knowledge chunk format has been implemented, allowing guideline information to be grouped into discrete packages (or modules) of information on a disease-specific topic or management issue. Aiming to improve the quality of care for heart transplant candidates, the recommendations present an evidence-based approach.

Reduction of Cardiac Allograft Vasculopathy by PCI: Quantification and Correlation With Outcome After Heart Transplantation

BACKGROUND

Percutaneous coronary intervention (PCI) might improve outcome at severe stages of cardiac allograft vasculopathy (CAV) among patients after heart transplantation (HTx). Yet, risk stratification of HTx patients after PCI remains challenging.

AIMS

To assess whether the International Society for Heart and Lung Transplantation (ISHLT) CAV classification remains prognostic after PCI and whether risk-stratification models of non-transplanted patients extend to HTx patients with CAV.

METHODS

At 2 European academic centers, 203 patients were stratified in cohort 1 (ISHLT CAV1, without PCI, n = 126) or cohort 2 (ISHLT CAV2 and 3, with PCI). At first diagnosis of CAV or first PCI, respectively, ISHLT CAV grades, SYNTAX scores I and II (SXS-I, SXS-II) were used to quantify baseline and residual CAV (rISHLT, rSXS-I, rSXS-II). RSXS-I > 0 defined incomplete revascularization (IR).

RESULTS

SXS-II predicted mortality in cohort 1 (P = 0.004), whereas SXS-I (P = 0.009) and SXS-II (P = 0.002) predicted mortality in cohort 2. Post-PCI, IR (P = 0.004), high rISHLT (P = 0.02) and highest tertile of rSXS-II (P = 0.006) were associated with higher 5-year mortality. In bivariable Cox analysis, baseline SXS-II, IR and rSXS-II remained predictors of 5-year mortality post-PCI. There was a strong inverse relationship between baseline and rSXS-I (r = -0.55; P < 0.001 and r = -0.50; P = 0.003, respectively) regarding the interval to first reintervention.

CONCLUSION

People with ISHLT CAV classification could apply for risk stratification after PCI. SYNTAX scores could be complemental for risk stratification and individualization of invasive follow-up of HTx patients with CAV.

The use of extracorporeal photopheresis in solid organ transplantation-current status and future directions

Prevention and management of allograft rejection urgently require more effective therapeutic solutions. Current immunosuppressive therapies used in solid organ transplantation, while effective in reducing the risk of acute rejection, are associated with substantial adverse effects. There is, therefore, a need for agents that can provide immunomodulation, supporting graft tolerance, while minimizing the need for immunosuppression. Extracorporeal photopheresis (ECP) is an immunomodulatory therapy currently recommended in international guidelines as an adjunctive treatment for the prevention and management of organ rejection in heart and lung transplantations. This article reviews clinical experience and ongoing research with ECP for organ rejection in heart and lung transplantations, as well as emerging findings in kidney and liver transplantation. ECP, due to its immunomodulatory and immunosuppressive-sparing effects, offers a potential therapeutic option in these settings, particularly in high-risk patients with comorbidities, infectious complications, or malignancies.

Patterns and Risk Factors for Rehospitalizations Within the First 90 Days Following Discharge After Heart Transplantation

BACKGROUND

Heart transplantation (HT) recipients are at risk for urgent rehospitalizations following discharge. However, data on prevalence, risk factors and clinical outcomes associated with post-HT rehospitalization are limited.

METHODS

This study aims to describe patterns of urgent rehospitalizations in HT recipients at a cardiology reference center in Brazil. Rehospitalizations and deaths occurring within the first 90 days following hospital discharge were identified. Regression models were used to identify variables associated with urgent rehospitalizations.

RESULTS

A total of 239 patients were included. Of those, 118 (49.4%) presented with a rehospitalization within 90 days following hospital discharge and 5 (2.01%) died. Most patients who were rehospitalized had one new hospital admission (86.0%). The main cause of urgent rehospitalization was infection (55.0%). In the multivariate analysis, elevated C-reactive protein at discharge and the occurrence of intracranial bleeding at index hospitalization were associated with an increased risk of readmission. Longer duration of index hospitalization and use of lower doses of azathioprine were associated with a lower risk of rehospitalization.

CONCLUSION

Around half of HT recipients were rehospitalized within the first 90 days after hospital discharge. Understanding factors associated with post-HT rehospitalization may help the implementation of strategies to avoid patient morbidity and hospital costs.

Assessing the Impact of Posaconazole Cessation on Tacrolimus Serum Concentrations and Incident Cardiac Allograft Rejection: Take Caution

Invasive aspergillosis (IA) is a rare and often fatal complication of immunosuppression following orthotopic heart transplant. Prophylaxis plays a crucial role in preventing the emergence of this opportunistic infection. The azole class of medications are the bellwether agents utilized in this patient population. Unfortunately, given their impact on the Cytochrome P450 enzyme system, significant fluctuations in serum tacrolimus concentrations occur when initiating and stopping azole therapy, increasing the risk for prolonged periods of sub-optimal immunosuppression. While there are recommended dosing adjustments for these transition periods based on small data sets primarily with fluconazole, there is no published literature on recommended dosing adjustments for posaconazole. Given our institution utilizes posaconazole as the primary therapeutic for aspergillosis prophylaxis, we aimed to explore and report our local data to better guide dosing decisions during these transition periods.

Obesity, Challenges, and Weight-Loss Strategies for Patients With Ventricular Assist Devices

For adults with advanced heart failure, class II/III obesity (body mass index ≥35 kg/m2) represents major challenges, and it is even considered a contraindication for heart transplantation (HT) at many centers. This has led to growing interest in preventing and treating obesity to help patients with advanced heart failure become HT candidates. Among all weight-loss strategies, bariatric surgery (BSx) has the greatest weight loss efficacy and has shown value in enabling select patients with left ventricular assist devices (LVADs) and obesity to lose sufficient weight to access HT. Nevertheless, both BSx and antiobesity medications warrant caution in the LVAD population. In this review, the authors describe and interpret the available published reports on the impact of obesity and weight-loss strategies for patients with LVADs from general and HT candidacy standpoints. The authors also provide an overview of the journey of LVAD recipients who undergo BSx and review major aspects of perioperative protocols.

Donor-Specific Antibody Testing is an Effective Surveillance Strategy for High-Risk Antibody Mediated Rejection in Heart Transplant Patients in the Contemporary Era

Background

Pathologic antibody mediated rejection (pAMR) evaluation and donor specific antibody (DSA) testing are recommended in the first year after heart transplantation (HTx) in adult patients. Whether DSA testing adds prognostic information to contemporary pAMR surveillance has not been fully studied.

Methods

This was a single center study of consecutive endomyocardial biopsies (EMB) performed between November 2010 and February 2023 in adult HTx patients. The primary objective was to evaluate whether DSA testing contributes additional information to pAMR surveillance to better predict overall survival. Secondary endpoints included cardiac allograft dysfunction and loss.

Results

A total of 6,033 EMBs from 544 HTx patients were reviewed for the study. The pAMR+/DSA+ group had significantly lower overall survival versus the pAMR-/DSA- group (hazard ratio [HR] = 2.63; 95% confidence interval [CI], 1.35-5.11; pc = 0.013). In the pAMR+/DSA+ group, patients with cardiac allograft dysfunction, compared to those without allograft dysfunction, had significantly lower overall and cardiac survival (pc < 0.001 for both). In contrast, pAMR+/DSA+ and pAMR-/DSA- patients without cardiac allograft dysfunction showed no difference in overall and cardiac survival. Primary graft dysfunction (PGD) was a novel risk factor for development of de novo DSAs (dnDSA) three weeks post-HTx (p = 0.007).

Conclusions

DSA testing as the primary surveillance method can identify high-risk pAMR+/DSA+ patients. Surveillance pAMR testing in the contemporary era may need to be reevaluated. Earlier DSA testing at 10-14 days post-HTx should be considered in PGD patients.

Toxic epidermal necrolysis following heart transplantation may caused by cefoperazone sodium and sulbactam sodium

BACKGROUND

The outcome of heart transplantation is significantly affected by perioperative infections. Individualised immunosuppression strategies are essential to reduce the risk of such infections.

CASE PRESENTATION

We report the successful management of a 56-year-old male patient diagnosed with dilated cardiomyopathy who underwent heart transplantation. During the perioperative period, the patient was prescribed cefoperazone sodium and sulbactam sodium, which induced a severe skin reaction: toxic epidermal necrolysis (TEN). The patient was treated with prednisone, immunoglobulins, etanercept, and other active immunomodulatory measures, together with an individualised anti-rejection regimen and physical therapy. The systemic rash resolved within a month, and the patient was successfully discharged after surgery.

CONCLUSION

Effective management of heart transplantation necessitates balancing immunosuppression and infection prevention. Individualised immunosuppressive strategies are critical for optimal clinical outcomes.

Application of graft-derived cell-free DNA for solid organ transplantation

Monitoring the status of grafts and the occurrence of postoperative complications, such as rejection, is crucial for ensuring the success and long-term survival of organ transplants. Traditional histopathological examination, though effective, is an invasive procedure and poses risks of complications, making frequent use impractical. In recent years, graft-derived cell-free DNA (gd-cfDNA) has emerged as a promising non-invasive biomarker. It not only provides early warnings of rejection and other types of graft injury but also offers important information about the effectiveness of immunosuppressive therapy and prognosis. gd-cfDNA shows potential in the monitoring of organ transplants. The early, real-time information on graft injury provided by gd-cfDNA facilitates timely individualized treatment and improves patient outcomes. However, the progress of research on gd-cfDNA varies across different organs. Therefore, this article will comprehensively review the application and findings of gd-cfDNA in monitoring various solid organs, discussing the advantages, limitations, and some future research directions to aid in its clinical application.

Exercise as a modality to improve heart transplantation-related functional impairments: An article review

Heart transplantation (HT), the treatment choice of advanced heart failure patients, is proven effective in increasing the survival and functional status of the recipients. However, compared to normal controls, functional status is lower in HT recipients. Exercise given in cardiac rehabilitation has been shown to improve exercise capacity as measured with peak oxygen uptake (VO2 peak) and muscle strength after completion of the program and cessation of exercise results in loss of exercise benefits. Several factors related to cardiac denervation and the use of immunosuppressive agents in HT recipients result in functional impairments including cardiovascular, pulmonary, exercise capacity, psychological, and quality of life (QoL) problems. High-intensity interval training (HIIT) is the most common type of exercise used in HT recipients and given as a hospital-based program. Improvement of functional impairments was found to have occurred due to primarily musculoskeletal adaptations through improvement of muscle structure and aerobic capacity and cardiovascular adaptations. In general, exercise given after transplantation improved VO2 peak significantly and improvement was better in the HIIT group compared to moderate intensity continuous training or no-exercise groups. Improvement of QoL was ascribed to improvement of exercise capacity, symptoms, pulmonary function, physical capacity improvement, anxiety, and depression.

Circulating extracellular vesicles as biomarkers in the diagnosis, prognosis and therapy of cardiovascular diseases

Cardiovascular disease (CVD) ranks among the primary contributors to worldwide mortality. Hence, the importance of constant research on new circulating biomarkers for the improvement of early diagnosis and prognostication of different CVDs and the development and refinement of therapeutic measures is critical. Extracellular vesicles (EV) have a great potential as diagnostic and prognostic markers, as they represent their parent cell by enclosing cell-specific molecules, which can differ in quality and quantity based on cell state. Assuming that all cell types of the cardiovascular system are capable of releasing EV into circulation, an emerging body of evidence has investigated the potential role of serum- or plasma-derived EV in CVD. Comprehensive research has unveiled alterations in EV quantity and EV-bound cargo in the form of RNA, proteins and lipids in the context of common CVDs such as coronary artery disease, atrial fibrillation, heart failure or inflammatory heart diseases, highlighting their diagnostic and prognostic relevance. In numerous in vitro and in vivo models, EV also showed promising therapeutic potential. However, translation of EV studies to a preclinical or clinical setting has proven to be challenging. This review is intended to provide an overview of the most relevant studies in the field of serum or plasma-derived EV.