Patients Awaiting Heart Transplantation Research Articles

Impact and predictors of positive response to desensitization in pediatric heart transplant candidates.

Desensitization, the process of reducing anti-human leukocyte antigen (HLA) antibodies in sensitized patients awaiting heart transplantation (HT), has unclear efficacy in pediatric HT candidates. Pediatric HT candidates listed at our institution between January 1, 2013 and June 30, 2018 were retrospectively evaluated. Sensitization was defined as the calculated panel reactive antibody (cPRA) ≥ 10% with ≥ 1 a strong positive antibody. The desensitization response was defined as a ≥ 25% reduction in the mean fluorescence intensity (MFI) for ≥ 90% of the strong positive antibodies on follow-up panel reactive antibody (PRA) testing before waitlist removal, HT, or death (data available for 13 patients). The HT candidates were categorized as sensitized receiving desensitization therapy (ST, n = 14), sensitized not receiving therapy (SNT, n = 18), or non-sensitized (n = 55). A desensitization response was observed in 8 (62%) of the ST upon repeat PRA testing, with the ST responders receiving more doses of intravenous immunoglobulin (IVIG) (8 vs 2, p < 0.05). The anti-HLA class I antibodies were particularly resistant for non-responders (p = 1.9 × 10-4). The combination of homograft and ventricular assist device was more sensitizing than either alone (p = 3.1 × 10-4). However, these sensitization risk factors did not impact the desensitization response. The ST was associated with a higher likelihood of remaining listed and a longer waitlist time without substantially impacting the HT rate, waitlist mortality, or early post-HT outcomes. Most ST patients had a favorable response to desensitization, with a dose-dependent response observed for IVIG. The anti-HLA class likely impacts the ST response, whereas traditional sensitization risk factors had no impact on the response.

The Effect of an Educational Video on Device-Related Concerns in a Single-Center Left Ventricular Assist Device Population

Introduction Left ventricular assist device (LVAD) implantations are increasing across the country as a treatment modality for patients with end-stage heart failure. With the increasing prevalence of patients with these devices, there is an urgent need for improved education addressing lifestyle considerations and concerns. The purposes of this study were to evaluate the prevalence of various concerns among patients with an LVAD and evaluate the effect of a short educational video intervention on reducing those concerns in a single-center adult LVAD population. Hypothesis We hypothesize that through the implementation of a short, educational video focused on specific device-related concerns, patients will report lower levels of these device-related concerns. Methods A 15-point LVAD Concerns Scale was created to evaluate the prevalence of specific device-related concerns. An educational video was created to address the concerns presented in the LVAD Concerns Scale. Data collection took place from November 2018 to February 2019. A cross-sectional, pre-test post-test study design was used to both identify various device-related concerns that exist among patients with an LVAD and examine the effectiveness of an educational intervention on reducing patients’ device-related concerns. Results Of the available patients with an LVAD who met inclusion criteria, 30 were enrolled to participate. The highest concerns were related to the LVAD abruptly malfunctioning, being a burden to their partner or family, and having no warning the device may malfunction. The average total score pre-video was 22 ± 14, and post-video the mean total score was 17 ± 13 (p-value = 0.002). Six individual questions saw statistically significant reductions in scores post-video. Conclusions Implementation of an educational intervention tailored to address patients’ specific LVAD related concerns resulted in a statistically significant decrease in those concerns. With the disparity between the number of patients awaiting heart transplantation and the number of available donor hearts, LVADs are being used with increased frequency to treat advanced heart failure. Use of the educational intervention we developed may improve important patient outcomes.

Impact of Left Ventricular Assist Device Exchange on Outcomes After Heart Transplantation

Left ventricular assist devices (LVADs) are the most common mode of circulatory support for patients awaiting heart transplantation. Unfortunately, a fraction of these patients require pump exchange during their course for pump-related adverse events. This study examined whether LVAD exchanges affect posttransplantation outcomes. This study focused on adult patients in the Organ Procurement and Transplantation Network database who were bridged to transplant with a LVAD implanted between 2007 and 2017. Patients who underwent LVAD exchange were compared with those supported with a single device. The primary end point was all-cause mortality at 1, 2, and 5 years after transplantation. The impact of device exchange on risk-adjusted outcomes was examined using Cox proportional hazards models. Among 8239 patients who met the inclusion criteria, there were 611 pump exchanges in 560 patients (7% of recipients). The pump exchange rate was 6.24 events per 100 patient-years. Survival at 5 years was lower for those who underwent LVAD exchange (69.4% vs 77.5%, log-rank P= .027). This finding was similar for risk-adjusted 5-year mortality (hazard ratio, 1.36; 95% confidence interval, 1.11 to 1.67; P= .003). Subgroup analysis revealed lower 5-year survival for female recipients who underwent LVAD exchange (55.4% vs 79.7%, log-rank P < .001). The interaction between female sex and LVAD exchange was associated with increased risk-adjusted 5-year mortality (hazard ratio, 1.65; 95% confidence interval, 1.05 to 2.59; P= .030). Recipients who underwent pump exchange while awaiting heart transplantation had a higher mortality compared with those on a primary device. Subgroup analysis revealed a marked increase in mortality of female recipients who experienced LVAD exchange.

Canine-Assisted Therapy in Hospitalized Patients Awaiting Heart Transplantation.

Patients awaiting heart transplantation can be listed for prolonged periods of time and, as a result, the prevalence of anxiety and depression is high. Our study evaluates the feasibility of canine-assisted therapy (CAT) in this population. A prospective, multicenter study was performed on all status 1a patients admitted during a 12-month period to await transplantation. Patients were asked to complete the Generalized Anxiety Disorder 7-item scale and the Patient Health Questionnaire-9 at baseline, week 2, and week 6, and the Perceived Stress Scale at baseline and week 4. At the conclusion of the study, patients completed a questionnaire assessing the overall efficacy of CAT. Baseline measures demonstrated high levels of anxiety, depression, and stress. The complete Generalized Anxiety Disorder 7-item scale (average score 10.9 vs 8; P = 0.14) and the Patient Health Questionnaire-9 (average score 12.3 vs 9.5; P = 0.057) scores decreased from baseline to week 6 and the Perceived Stress Scale (average score 29.8 vs 27; P = 0.16) decreased from baseline to week 4 with trends toward significance. All of the patients perceived CAT as improving the overall quality of hospitalization, would recommend CAT to other patients, and would elect for CAT during subsequent admissions. No infectious concerns were reported. Anxiety, stress, and depression are prevalent among 1a heart transplantation candidates, and CAT is a welcomed adjunct to the usual medical care in this population.

Desensitization for sensitized patients awaiting heart transplant.

This review summarizes contemporary desensitization strategies for patients awaiting cardiac transplantation in an era when specific management is still somewhat controversial. The number of sensitized patients awaiting heart transplantation is rising. Clinical assessment of antibody levels is mostly focused on human leukocyte antigen (HLA) antibodies. Sensitization to HLA antigens increases the risk of antibody medicated rejection and cardiac allograft vasculopathy after transplant, thus translates to reduced access to compatible donors and increased wait time to transplant. Desensitization therapy is commonly considered in listed patients with cPRA more than 50%, to either decrease the amount of circulating anti-HLA antibodies, reduce the antibody production, or a combination of both. Despite promising results on specific therapies (e.g., plasmapheresis, intravenous immunoglobulin, rituximab, bortezomib), there is a significant gap in knowledge on desensitization therapies in heart transplantation. Most data are from small observational studies and extrapolated from nonheart solid organ transplants. Management of the sensitized patient awaiting heart transplant is individualized. Desensitization can facilitate negative cross-match and successful transplantation, but is associated with significant cost and potential adverse effects. The long-term outcomes of desensitization therapy remain to be determined, further emphasizing the importance of personalizing the treatment approach to each patient.

Routine Right Heart Catheterization in LVAD Patients Awaiting Heart Transplant: What is the Appropriate Surveillance Interval?

Purpose ISHLT guidelines recommend serial right heart catheterization (RHC) to survey pulmonary hypertension in patients awaiting heart transplant. In LVAD as BTT patients the ideal surveillance frequency is unknown in those without prior pulmonary hypertension or whose pre-LVAD PVR normalized after surgery. Here, we review the utility of our surveillance RHC protocol. Methods Between January 2017 and July 2018, 69 patients who received an LVAD as BTT were studied. Routine RHC was performed every six months irrespective of prior PVR. Hemodynamic variables were retrospectively collected and reviewed. Results In 69 patients, 217 RHCs were analyzed. The median age was 55 years (IQR=15), and 55 (80%) were male. Median follow-up period was 18.4 months, and hemodynamic variables were largely unchanged post-LVAD (Table). Post-LVAD, overall PVR decreased from 3.5 ± 2.1 to 2.4 ± 1.0 Wood units (p = 7.2e-5) at six months and stabilized below 3 at all time points. Thirty-three patients (48%) had PVR ≤ 3 (1.8 ± 0.7), and 36 patients (52%) had PVR > 3 (4.9 ± 2.0) pre-LVAD. Both groups exhibited stabilization of PVR with mean 3 at any point after LVAD implantation, 13 (81%) had a pre-LVAD PVR > 3. No patients with a PVR ≤ 3 six months post-LVAD implantation presented with a PVR > 3 at any subsequent RHC. Of the 40 patients (58%) transplanted, one patient developed severe primary graft dysfunction with right ventricular failure. Conclusion Routine RHC every six months may not be necessary for BTT patients, particularly for those with PVR ≤ 3 six months post LVAD.

Dose-Dependent Response to Desensitization in Pediatric Heart Transplant Candidates Assessed by Single Antigen Bead Technology

Purpose The efficacy of desensitization, the process of reducing anti-HLA antibodies in sensitized patients awaiting heart transplantation (HT), is unclear in pediatric HT candidates. Methods To evaluate the impact of DS in pediatric HT candidates, we performed a retrospective analysis of all patients listed for HT between 1/1/10 - 6/30/18 at our institution. Sensitized patients were defined as having a panel reactive antibody (PRA) ≥ 10% and ≥1 strong positive antibody with mean fluorescence intensity (MFI) ≥ 5500. Patients were identified as nonsensitized (NS, n = 55), sensitized but no therapy (S-NT, n = 18), and sensitized undergoing desensitization therapy (S-DS, n = 14). Response to desensitization was defined as ≥25% reduction in the MFI for ≥90% of strong positive antibodies for whom follow up PRA testing was performed prior to delisting, HT, or death (n = 13). Results DS consisted of IVIG and rituximab for all patients; 2 also received bortezomib. DS responders, defined by reduction in antibody burden (n = 8), received on average more doses of IVIG than nonresponders (9 vs 3, p = 0.04). All five S-DS patients that received HT during the study period had a negative flow crossmatch (FXM) and most (80%) would have had a positive FXM with historical serum. All S-DS had history of single ventricle congenital heart disease and homograft exposure. Prior VAD was associated with sensitization severity (mean positive antibodies 75 vs 26, p = 0.01) but not response to DS, and history of ECMO was associated with neither. S-DS compared S-NT were on average more sensitized (mean number of high MFI antibodies 45 vs 21, p = 0.04), waited longer for HT (569 vs 148 days, p = 0.005), and trended towards higher waitlist mortality (36% vs 11%, p = 0.09). NS patients were less likely to have homograft exposure (p Conclusion A favorable response to DS was observed in most patients in this cohort. Homograft and VAD, but not ECMO, were associated with severity of sensitization. IVIG appears to have some benefit, with a dose-dependent effect. Post-HT outcomes for S-DS, S-NT, and NS patients were similar in this study.

Cardiac Transplantation across Preformed HLA-Antibody Barriers: Results of a Peritransplant Desensitization Protocol

Purpose A growing number of patients awaiting heart transplantation presents with preformed anti-HLA antibodies. This allosensitization prolongs waiting times and increases morbidity and mortality. In 2017, we designed aprotocol for peritransplant desensitization of heart-transplanted patients showing preformed anti-HLA donor specific antibodies (pfDSA), i.e. a positive virtual crossmatch. The protocol included: an intraoperative single dose of the IL-6 receptor antibody Tocilizumab (10mg/kg) just before releasing the aortic clamp; 5 sessions of plasmapheresis (PE, 1 before transplantation, 1 during transplantation and 3 thereafter); an infusion (2g/kg) of IgA and IgM-enriched human immunoglobulins G (IgGAM) after the last PE; and a single Rituximab dose (375mg/m2) after IgGAM. IgGAM are repeated every 4 weeks (0.5g/kg) for a maximum of 6 months, if DSA are still positive. Aim of this study was to present the preliminary results of this peritransplant desensitization protocol. Methods Records of heart-transplanted patients at our institution between 01/2017 and 10/2018 were reviewed. Patients with pfDSA (positive virtual crossmatch) formed the case group, remaining patients the control group. Median (IQR) follow-up amounted to 9 (5, 16) months. Results During the study period, among the 42 transplanted patients, 9 (21%) patients formed the case group and the remaining 33 (79%) the control group. All 9 case patients showed pfDSA with >50% pre-transplant panel reactive antibodies (PRA). Pretransplant recipient and donor characteristics did not differ between groups. Post-transplant, no case patients showed severe primary graft dysfunction, but 6 (19%) control patients did (p=0.19). At treatment end, pfDSA were cleared in 4 (44%) patients. At 1-year follow-up, survival was 100% vs. 75% in case and control patients (p=0.18); freedom from biopsy-confirmed rejection (Grade >1R) was 89% vs. 92% in case (n=1) and control (n=2) patients (p=0.78); and from steroid-pulsed therapy 89% vs. 82% in case (n=1) and control (n=5) patients (p=0.76), respectively. One case patient showed minimal AMR (pAMR 1+). Conclusion The present study showed that heart transplantation across positive crossmatch barriers can be feasible and safe. The present peritransplant desensitization protocol yielded good survival and rejection-free survival.

Comparative Efficacy of Bortezomib and Carfilzomib Desensitization Protocols in Highly Sensitized Cardiac Transplant Candidates

Purpose At our center, patients who are deemed highly sensitized may undergo a proteasome inhibitor-based desensitization protocol to shorten organ wait time and improve the probability of finding an acceptable donor. The purpose of this study is to evaluate the comparative effects on detectable anti-HLA antibodies between our center's bortezomib-based and carfilzomib-based protocol in sensitized patients awaiting heart transplantation. Methods This was a retrospective cohort study. Highly sensitized patients awaiting cardiac transplant who underwent the desensitization protocol between April 2013 and February 2017 were included in the study. Protocol included either a bortezomib or carfilzomib-based regimen with multiple plasmapheresis sessions and a single dose of rituximab. Efficacy of these two desensitization regimens was evaluated by comparing trends in pre- and post-protocol positive (mean fluorescence intensity (MFI) greater than 500) anti-HLA antibody allele specificities. Results Of the 19 patients who underwent a desensitization protocol, 8 patients received a bortezomib-based regimen and 11 patients a carfilzomib-based regimen. When comparing trends in both HLA class I and class II antibodies pre- and post- desensitization protocol, patients who received a bortezomib-based regimen experienced a greater reduction (p Conclusion In our observed cohort, bortezomib-based desensitization protocol was associated with a greater percent reduction of anti-HLA antibody alleles with MFI>500 compared to the carfilzomib-based desensitization protocol. Larger, prospective randomized studies are needed to confirm these results.

Mechanical Circulatory Support Patients Awaiting Heart Transplant with Positive AT1R Antibodies Have Acceptable Outcome Post-Heart Transplant

Mechanical Circulatory Support Patients Awaiting Heart Transplant with Positive AT1R Antibodies Have Acceptable Outcome Post-Heart Transplant

Cardiac transplantation across preformed HLA-antibody barriers

Cardiac transplantation across preformed HLA-antibody barriers

Pediatric marginal donor hearts: Trends in US national use, 2005-2014.

Pediatric patients awaiting heart transplant face high mortality rates due to donor organ shortages, including non-use of marginal donor hearts. We examined national trends in pediatric marginal donor heart use over time. UNOS data were queried for heart donors <18years from 2005 to 2014. The proportion of donor hearts considered marginal was determined using previously cited marginal characteristics: left ventricular ejection fraction (LVEF) <50%, use of ≥2 inotropes, cerebrovascular death, CDC high-risk status, and eGFR<30mL/min/1.73m2 . Disposition of donor hearts was determined and stratified by marginal donor status. Of 6778 pediatric hearts offered from 2005 to 2014, 2373 (35.0%) were considered marginal. Non-use of marginal donor hearts was significantly higher than that of donor hearts without any marginal characteristics (59.5% vs 20.3%, P<.001). In particular, LVEF<50% and donor inotropes were associated with high rates of organ non-use among pediatric donors. Yet, non-use of marginal donor organs decreased from 67% to 48% from 2005 to 2014 (P<.001). Although the proportion of pediatric donor hearts used for pediatric patients has increased, more than half of donor hearts are declined for use in pediatric recipients due, in part, to perceived marginal status.

Risk of Post-Transplant De Novo Donor Specific Antibodies in Patients Receiving Transfusions Perioperatively

Blood transfusions have been established to induce HLA sensitization, of particular importance in patients awaiting heart transplantation (HTx). It is unclear if perioperative transfusions at the time of HTx induce significant sensitization, leading to the development of de novo DSA following HTx.

Pre-transplant Anti-nuclear Antibodies Correlate With Post-transplant Donor-specific Antibodies: A Link between Autoimmunity and Graft Failure?

Antinuclear antibodies (ANA) are routinely used as a marker of autoimmunity. The presence of clinically significant ANA titers in patients awaiting heart transplantation has been associated with increased mortality. This study aims to investigate the association between pre-transplant ANA titer and pathological indicators of antibody-mediated rejection in heart transplant patients.

Association between myocardial extracellular volume and strain analysis through cardiovascular magnetic resonance with histological myocardial fibrosis in patients awaiting heart transplantation

BackgroundCardiovascular magnetic resonance (CMR)-derived extracellular volume (ECV) and tissue tracking strain analyses are proposed as non-invasive methods for quantifying myocardial fibrosis and deformation. This study sought (1) to histologically validate myocardial ECV against the collagen volume fraction (CVF) measured from tissue samples of patients undergoing heart transplantation and (2) to detect the correlations between myocardial systolic strain and the myocardial ECV and histological CVF in patients undergoing heart transplantation.MethodsA total of 12 dilated cardiomyopathy (DCM) and 10 ischaemic cardiomyopathy (ICM) patients underwent T1 mapping with the Modified Look Locker Inversion recovery (MOLLI) sequence, T2 mapping and ECV. Myocardial systolic strain, including left ventricular global longitudinal (GLS), circumferential (GCS) and radial strain (GRS), were quantified using CMR cine images with tissue tracking analysis software. Tissue samples were collected from each of 16 segments of the explanted hearts and were stained with picrosirius red for histological CVF quantification.ResultsA strong relationship was observed between the global myocardial ECV and histological CVF in the DCM and ICM patients based on a per-patient analysis (r = 0.904 and r = 0.901, respectively, p < 0.001). In the linear mixed-effects regression analysis, ECV correlated well with the histological CVF in the DCM and ICM patients on a per-segment basis (β = 0.838 and β = 0.915, respectively, p < 0.001). In the multivariate linear regression analysis, histological CVF was the strongest independent determinant of ECV in the patients awaiting heart transplantation (standardised β = 0.860, p < 0.001). However, the T2 time, GLS, GCS and GRS showed no significant associations with ECV and CVF in the patients awaiting heart transplantation.ConclusionsECV derived from CMR correlated well with histological CVF, indicating its potential as a non-invasive tool for the quantification of myocardial fibrosis. Additionally, impaired myocardial systolic strains were not associated with the ECV and CVF in the patients awaiting heart transplantation.

Age-Dependent Association Between Pre-transplant Blood Transfusion and Outcomes of Pediatric Heart Transplantation.

Avoidance of red blood cell (RBC) transfusions in patients awaiting heart transplantation (HTx) has been suggested to minimize the risk of allosensitization. Although recent studies have suggested that an immature immune system in younger HTx recipients may reduce risks associated with RBC transfusion, the role of age in moderating the influence of transfusion on HTx outcomes remains unclear. We used available data from a national transplant registry to explore whether the association between pre-transplant transfusions and outcomes of pediatric HTx varies by patient age. De-identified data were obtained from the United Network for Organ Sharing registry, including first-time recipients of isolated HTx performed at age 0-17years in 1995-2015. The primary exposure was receiving blood transfusions within 2 weeks prior to HTx. Patient survival after HTx was evaluated using multivariable Cox proportional hazards, where age at transplant was interacted with exposure to pre-transplant transfusion. Age-specific hazard ratios (HRs) of pre-transplant transfusion were plotted across ages at transplant. There were 4883 patients meeting inclusion criteria, of whom 1258 died during follow-up (mean follow-up duration 6 ± 5years). Patients receiving pre-transplant transfusions were distinguished by younger age, higher prevalence of prior cardiac surgery, greater likelihood of being in the intensive care unit, and greater use of left ventricular assist device bridge to transplant. In multivariable analysis, pre-transplant transfusions were associated with increased mortality hazard among infants < 1year of age (HR = 1.46; 95% CI 1.23, 1.74; p < 0.001). For each additional year of age, the excess hazard associated with pre-transplant transfusions decreased by 3% (interaction HR = 0.97; 95% CI 0.98, 0.99; p = 0.003). By age 8, the association between pre-transplant transfusions and post-transplant mortality was no longer statistically significant (HR = 1.15; 95% CI 0.99, 1.32; p = 0.060). Pre-transplant transfusions were associated with increased mortality hazard only among younger children (age < 8years) undergoing HTx. These data support the current practices of transfusion avoidance prior to HTx, particularly in younger patients.

Successful heart transplantation in patients with total artificial heart infections.

Data are limited on clinical outcomes in patients awaiting heart transplant (HT) with total artificial heart (TAH) infections. We retrospectively reviewed all TAH recipients at our center. TAH infection was classified as definite if a microorganism was isolated in cultures from the exit site or deep tissues around the TAH; as probable in patients without surgical or microbiologic evidence of infection but no other explanation for persistent or recurrent bloodstream infection (BSI); or possible in patients with clinical suspicion and radiographic findings suggestive of TAH infection, but without surgical intervention or microbiologic evidence. From 2012 to 2015, a total of 13 patients received a TAH, with a median age at implantation of 52years (range: 28-60). TAH infection occurred in nine patients (seven definite, one probable, one possible) a median of 41days after implant (range: 17-475). The majority of TAH infections were caused by Staphylococcus species. Seven of nine patients underwent HT (four had pre-HT mediastinal washout, and five had positive HT operative cultures). Three patients had an active BSI caused by the same pathogen causing TAH infection at the time of HT, with one developing a post-HT BSI with the same bacteria. No patient developed post-HT surgical site infection caused by the TAH infection pathogen. No deaths among HT recipients were attributed to infection. TAH infection is frequently associated with BSI and mediastinitis and Staphylococcus was the most common pathogen. A multimodal approach of appropriate pre- and post-HT antimicrobial therapy, surgical drainage, and heart transplantation with radical mediastinal debridement was successful in curing infection.

Abstract 21394: Socioeconomic and Racial Disparities in Outcomes Among Patients Listed for Heart Transplant in the United States

Background: Socioeconomic and racial disparities in outcomes among patients with heart failure are well-documented. Whether such disparities exist among patients awaiting heart transplant (HT) is unclear. We aimed to characterize the associations of socioeconomic status (SES) and race with outcomes among patients listed for HT. Methods: Patients listed for heart transplant between 1994 and 2014 were included (n = 64,276). SES indicators included insurance status, education, and neighborhood SES (nSES), measured by zip code using a composite index. The primary outcome was a composite of death or delisting and the secondary outcome was transplant. Multivariate analyses were employed to adjust for race, SES, comorbidity, and clinical severity at time of listing. Results: Non-white race, low education, Medicare, Medicaid, and lower nSES (Figure 1) were associated with higher unadjusted risks of death or delisting. After adjustment, the associations with less than high school (HR=1.39) and college education (HR=0.93), Medicare (HR=1.22), Medicaid (HR=1.16), and lowest nSES quartile (HR=1.06) remained significant (p &lt; 0.05; Figure 2). Risks associated with black race and low nSES decreased significantly over time. Adjusted incidence of transplant was significantly lower among blacks (HR = 0.90), but higher among other non-white patients. Conclusions: Low SES is associated with poorer outcomes during HT listing, and there are racial disparities in the likelihood of transplant. Some of these disparities have narrowed over time. Further research is needed to identify the underlying cause of these disparities, which are not explained by measured clinical characteristics.

Continuation of Beta Blocker Therapy Reduces Hospitalizations in Patients Treated with Milrinone as a Bridge to Transplant

Introduction: Patients awaiting heart transplantation (HTx) are frequently “bridged” to transplant with outpatient milrinone infusions. Such patients are often quite ill and require frequent hospitalizations while awaiting definitive therapy. The potential benefits of continuing standard oral HF pharmacotherapy in this population remain unclear. We sought to determine whether continuation of neurohormonal blockade would reduce hospitalizations in this very ill population. Methods: Single-center, retrospective analysis of 101 advanced HF patients discharged home on continuous milrinone infusion as a bridge to HTx. The primary outcome was the mean number of hospitalizations per days of follow-up. Results: Hemodynamic, ECHO, and laboratory variables were consistent with an advanced heart failure population (Table 1). The median dose of milrinone used was 0.25 (IQR 0.25 - 0.375) mcg/kg/min. The majority of patients were maintained on beta blockers (88%) and MRAs (61%), while a minority were continued on ACEi/ARB therapy (30%). The mean number of hospitalizations per patient was 1.93 + /- 1.77 and the mean number of hospitalizations per days of follow-up was 0.0185 + /- 0.0180. The use of beta-blockers was associated with a statistically significant 50% reduction in the number of hospitalizations per days of follow-up (P = .003)(Fig. 1). There was no difference seen with the use of ACEi/ARB or MRA therapies (p = NS).Conclusion: The continuation of beta-blockers in patients receiving continuous milrinone infusion as a bridge to HTx may reduce the risk of hospitalization by as much as 50%.Table 1Baseline patient characteristics (n = 101)Fig. 1Hospitalizations per days of follow-up, stratified by medication use.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Current concepts for sensitized patients before transplantation.

Antibody allosensitization poses a major immunologic challenge for patients awaiting heart transplantation. It is associated with significant morbidity and mortality for both pretransplant and posttransplant patients by prolonging wait times to transplant and increasing posttransplant rejection and vasculopathy. Many questions remain regarding methods and interpretation of antibody detection, the relevance of sensitization in specific patient populations such as those with mechanical circulatory support and the ideal strategies for desensitization. More sensitive and specific assays are now available to help identify and risk stratify highly sensitized patients. The growing field of mechanical circulatory support is introducing new questions and observations about sensitization in patients supported by ventricular-assist devices. Multiple desensitization therapies, including newer treatments such as bortezomib and eculizumab, targeting various components of the humoral immune response, appear to show promise by significantly reducing allosensitization and allowing for successful transplantation with good outcomes. The development of more accurate methods of detecting sensitization and defining the ideal desensitization strategies that can be more universally adopted and tested in clinical trials will serve to enlighten us and help many more highly sensitized patients not only make it to transplant, but also thrive posttransplant as well.