Surgical Treatment of Tricuspid Valve Regurgitation in Patients Undergoing Left Ventricular Assist Device Implantation: Interim analysis of the TVVAD trial

OBJECTIVES

Right heart failure remains a serious complication of left ventricular assist device therapy. Many patients presenting for left ventricular assist device implantation have significant tricuspid regurgitation. It remains unknown whether concurrent tricuspid valve surgery reduces postoperative right heart failure. The primary aim was to identify whether concurrent tricuspid valve surgery reduced the incidence of moderate or severe right heart failure within the first 6 months after left ventricular assist device implantation.

METHODS

Patients with moderate or severe tricuspid regurgitation on preoperative echocardiography were randomized to left ventricular assist device implantation alone (no tricuspid valve surgery) or with concurrent tricuspid valve surgery. Randomization was stratified by preoperative right ventricular dysfunction. The primary end point was the frequency of moderate or severe right heart failure within 6 months after surgery.

RESULTS

This report describes a planned interim analysis of the first 60 randomized patients. The tricuspid valve surgery group (n = 32) had mild or no tricuspid regurgitation more frequently on follow-up echocardiography studies compared with the no tricuspid valve surgery group (n = 28). However, at 6 months, the incidence of moderate and severe right heart failure was similar in each group (tricuspid valve surgery: 46.9% vs no tricuspid valve surgery: 50%, P = .81). There was no significant difference in postoperative mortality or requirement for right ventricular assist device between the groups. There were also no significant differences in secondary end points of functional status and adverse events.

CONCLUSIONS

The presence of significant tricuspid regurgitation before left ventricular assist device is associated with a high incidence of right heart failure within the first 6 months after surgery. Tricuspid valve surgery was successful in reducing postimplant tricuspid regurgitation compared with no tricuspid valve surgery but was not associated with a lower incidence of right heart failure.

Metabolomic profiling during ex situ normothermic perfusion before heart transplantation defines patterns of substrate utilization and correlates with markers of allograft injury

BACKGROUND

Cardiac metabolism is altered in heart failure and ischemia-reperfusion injury states. We hypothesized that metabolomic profiling during ex situ normothermic perfusion before heart transplantation (HT) would lend insight into myocardial substrate utilization and report on subclinical and clinical allograft dysfunction risk.

METHODS

Metabolomic profiling was performed on serial samples of ex situ normothermic perfusate assaying biomarkers of myocardial injury in lactate and cardiac troponin I (TnI) as well as metabolites (66 acylcarnitines, 15 amino acids, nonesterified fatty acids [NEFA], ketones, and 3-hydroxybutyrate). We tested for change over time in injury biomarkers and metabolites, along with differential changes by recovery strategy (donation after circulatory death [DCD] vs donation after brain death [DBD]). We examined associations between metabolites, injury biomarkers, and primary graft dysfunction (PGD). Analyses were performed using linear mixed models adjusted for recovery strategy, assay batch, donor-predicted heart mass, and time.

RESULTS

A total of 176 samples from 92 ex situ perfusion runs were taken from donors with a mean age of 35 (standard deviation 11.3) years and a median total ex situ perfusion time of 234 (interquartile range 84) minutes. Lactate trends over time differed significantly by recovery strategy, while TnI increased during ex situ perfusion regardless of DCD vs DBD status. We found fuel substrates were rapidly depleted during ex situ perfusion, most notably the branched-chain amino acids leucine/isoleucine, as well as ketones, 3-hydroxybutyrate, and NEFA (least squares [LS] mean difference from the first to last time point -1.7 to -4.5, false discovery rate q < 0.001). Several long-chain acylcarnitines (LCAC), including C16, C18, C18:1, C18:2, C18:3, C20:3, and C20:4, increased during the perfusion run (LS mean difference 0.42-0.67, q < 0.001). Many LCACs were strongly associated with lactate and TnI. The change over time of many LCACs was significantly different for DCD vs DBD, suggesting differential trends in fuel substrate utilization by ischemic injury pattern. Changes in leucine/isoleucine, arginine, C12:1-OH/C10:1-DC, and C16-OH/C14-DC were associated with increased odds of moderate-severe PGD. Neither end-of-run nor change in lactate or TnI was associated with PGD.

CONCLUSIONS

Metabolomic profiling of ex situ normothermic perfusion solution reveals a pattern of fuel substrate utilization that correlates with subclinical and clinical allograft dysfunction. This study highlights a potential role for interventions focused on fuel substrate modification in allograft conditioning during ex situ perfusion to improve allograft outcomes.

Early Outcomes in Patients With LVAD Undergoing Heart Transplant via Use of the SherpaPak Cardiac Transport System

BACKGROUND

Heart transplant (HT) in recipients with left ventricular assist devices (LVADs) is associated with poor early post-HT outcomes, including primary graft dysfunction (PGD). As complicated heart explants in recipients with LVADs may produce longer ischemic times, innovations in donor heart preservation may yield improved post-HT outcomes. The SherpaPak Cardiac Transport System is an organ preservation technology that maintains donor heart temperatures between 4 °C and 8 °C, which may minimize ischemic and cold-induced graft injuries. This analysis sought to identify whether the use of SherpaPak versus traditional cold storage was associated with differential outcomes among patients with durable LVAD undergoing HT.

METHODS

Global Utilization and Registry Database for Improved Heart Preservation-Heart (NCT04141605) is a multicenter registry assessing post-HT outcomes comparing 2 methods of donor heart preservation: SherpaPak versus traditional cold storage. A retrospective review of all patients with durable LVAD who underwent HT was performed. Outcomes assessed included rates of PGD, post-HT mechanical circulatory support use, and 30-day and 1-year survival.

RESULTS

SherpaPak (n=149) and traditional cold storage (n=178) patients had similar baseline characteristics. SherpaPak use was associated with reduced PGD (adjusted odds ratio, 0.56 [95% CI, 0.32-0.99]; P=0.045) and severe PGD (adjusted odds ratio, 0.31 [95% CI, 0.13-0.75]; P=0.009), despite an increased total ischemic time in the SherpaPak group. Propensity matched analysis also noted a trend toward reduced intensive care unit (SherpaPak 7.5±6.4 days versus traditional cold storage 11.3±18.8 days; P=0.09) and hospital (SherpaPak 20.5±11.9 days versus traditional cold storage 28.7±37.0 days; P=0.06) lengths of stay. The 30-day and 1-year survival was similar between groups.

CONCLUSIONS

SherpaPak use was associated with improved early post-HT outcomes among patients with LVAD undergoing HT. This innovation in preservation technology may be an option for HT candidates at increased risk for PGD.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04141605.

Donor Heart Recovery and Preservation Modalities in 2024

Historically, heart transplantation (HT) has relied on the use of traditional cold storage for donor heart preservation. This organ preservation modality has several limitations, including the risk for ischemic and cold-induced graft injuries that may contribute to primary graft dysfunction and poor post-HT outcomes. In recent years, several novel donor heart preservation modalities have entered clinical practice, including the SherpaPak Cardiac Transport System of controlled hypothermic preservation, and the Transmedics Organ Care System of ex vivo perfusion. Such technologies are altering the landscape of HT by expanding the geographic reach of procurement teams and enabling both donation after cardiac death and the use of expanded criteria donor hearts. This paper will review the emerging evidence on the association of these modalities with improved post-HT outcomes, and will also suggest best practices for selecting between donor heart preservation techniques.

Increasing Utilization of Extended Criteria Donor Hearts for Transplantation: The OCS Heart EXPAND Trial

BACKGROUND

Extended criteria donor (ECD) hearts available with donation after brain death (DBD) are underutilized for transplantation due to limitations of cold storage.

OBJECTIVES

This study evaluated use of an extracorporeal perfusion system on donor heart utilization and post-transplant outcomes in ECD DBD hearts.

METHODS

In this prospective, single-arm, multicenter study, adult heart transplant recipients received ECD hearts using an extracorporeal perfusion system if hearts met study criteria. The primary outcome was a composite of 30-day survival and absence of severe primary graft dysfunction (PGD). Secondary outcomes were donor heart utilization rate, 30-day survival, and incidence of severe PGD. The safety outcome was the mean number of heart graft-related serious adverse events within 30 days. Additional outcomes included survival through 2 years benchmarked to concurrent nonrandomized control subjects.

RESULTS

A total of 173 ECD DBD hearts were perfused; 150 (87%) were successfully transplanted; 23 (13%) did not meet study transplantation criteria. At 30 days, 92% of patients had survived and had no severe PGD. The 30-day survival was 97%, and the incidence of severe PGD was 6.7%. The mean number of heart graft-related serious adverse events within 30 days was 0.17 (95% CI: 0.11-0.23). Patient survival was 93%, 89%, and 86% at 6, 12, and 24 months, respectively, and was comparable with concurrent nonrandomized control subjects.

CONCLUSIONS

Use of an extracorporeal perfusion system resulted in successfully transplanting 87% of donor hearts with excellent patient survival to 2 years post-transplant and low rates of severe PGD. The ability to safely use ECD DBD hearts could substantially increase the number of heart transplants and expand access to patients in need. (International EXPAND Heart Pivotal Trial [EXPANDHeart]; NCT02323321; Heart EXPAND Continued Access Protocol; NCT03835754).

The Role of Recipient Thyroid Hormone Supplementation in Primary Graft Dysfunction After Heart Transplantation: A Propensity-Adjusted Analysis

OBJECTIVES

To investigate whether recipient administration of thyroid hormone (liothyronine [T3]) is associated with reduced rates of primary graft dysfunction (PGD) after orthotopic heart transplantation.

DESIGN

Retrospective cohort study.

SETTING

Single-center, university hospital.

PARTICIPANTS

Adult patients undergoing orthotopic heart transplantation.

INTERVENTIONS

A total of 609 adult heart transplant recipients were divided into 2 cohorts: patients who did not receive T3 (no T3 group, from 2009 to 2014), and patients who received T3 (T3 group, from 2015 to 2019). Propensity-adjusted logistic regression was performed to assess the association between T3 supplementation and PGD.

MEASUREMENTS AND MAIN RESULTS

After applying exclusion criteria and propensity-score analysis, the final cohort included 461 patients. The incidence of PGD was not significantly different between the groups (33.9% no T3 group v 40.8% T3 group; p = 0.32). Mortality at 30 days (3% no T3 group v 2% T3 group; p = 0.53) and 1 year (10% no T3 group v 12% T3 group; p = 0.26) were also not significantly different. When assessing the severity of PGD, there were no differences in the groups' rates of moderate PGD (not requiring mechanical circulatory support other than an intra-aortic balloon pump) or severe PGD (requiring mechanical circulatory support other than an intra-aortic balloon pump). However, segmented time regression analysis revealed that patients in the T3 group were less likely to develop severe PGD.

CONCLUSIONS

These findings indicated that recipient single-dose thyroid hormone administration may not protect against the development of PGD, but may attenuate the severity of PGD.

Inhaled Epoprostenol Compared With Nitric Oxide for Right Ventricular Support After Major Cardiac Surgery

BACKGROUND

Right ventricular failure (RVF) is a leading driver of morbidity and death after major cardiac surgery for advanced heart failure, including orthotopic heart transplantation and left ventricular assist device implantation. Inhaled pulmonary-selective vasodilators, such as inhaled epoprostenol (iEPO) and nitric oxide (iNO), are essential therapeutics for the prevention and medical management of postoperative RVF. However, there is limited evidence from clinical trials to guide agent selection despite the significant cost considerations of iNO therapy.

METHODS

In this double-blind trial, participants were stratified by assigned surgery and key preoperative prognostic features, then randomized to continuously receive either iEPO or iNO beginning at the time of separation from cardiopulmonary bypass with the continuation of treatment into the intensive care unit stay. The primary outcome was the composite RVF rate after both operations, defined after transplantation by the initiation of mechanical circulatory support for isolated RVF, and defined after left ventricular assist device implantation by moderate or severe right heart failure according to criteria from the Interagency Registry for Mechanically Assisted Circulatory Support. An equivalence margin of 15 percentage points was prespecified for between-group RVF risk difference. Secondary postoperative outcomes were assessed for treatment differences and included: mechanical ventilation duration; hospital and intensive care unit length of stay during the index hospitalization; acute kidney injury development including renal replacement therapy initiation; and death at 30 days, 90 days, and 1 year after surgery.

RESULTS

Of 231 randomized participants who met eligibility at the time of surgery, 120 received iEPO, and 111 received iNO. Primary outcome occurred in 30 participants (25.0%) in the iEPO group and 25 participants (22.5%) in the iNO group, for a risk difference of 2.5 percentage points (two one-sided test 90% CI, -6.6% to 11.6%) in support of equivalence. There were no significant between-group differences for any of the measured postoperative secondary outcomes.

CONCLUSIONS

Among patients undergoing major cardiac surgery for advanced heart failure, inhaled pulmonary-selective vasodilator treatment using iEPO was associated with similar risks for RVF development and development of other postoperative secondary outcomes compared with treatment using iNO.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03081052.

Transplantation Outcomes with Donor Hearts after Circulatory Death

BACKGROUND

Data showing the efficacy and safety of the transplantation of hearts obtained from donors after circulatory death as compared with hearts obtained from donors after brain death are limited.

METHODS

We conducted a randomized, noninferiority trial in which adult candidates for heart transplantation were assigned in a 3:1 ratio to receive a heart after the circulatory death of the donor or a heart from a donor after brain death if that heart was available first (circulatory-death group) or to receive only a heart that had been preserved with the use of traditional cold storage after the brain death of the donor (brain-death group). The primary end point was the risk-adjusted survival at 6 months in the as-treated circulatory-death group as compared with the brain-death group. The primary safety end point was serious adverse events associated with the heart graft at 30 days after transplantation.

RESULTS

A total of 180 patients underwent transplantation; 90 (assigned to the circulatory-death group) received a heart donated after circulatory death and 90 (regardless of group assignment) received a heart donated after brain death. A total of 166 transplant recipients were included in the as-treated primary analysis (80 who received a heart from a circulatory-death donor and 86 who received a heart from a brain-death donor). The risk-adjusted 6-month survival in the as-treated population was 94% (95% confidence interval [CI], 88 to 99) among recipients of a heart from a circulatory-death donor, as compared with 90% (95% CI, 84 to 97) among recipients of a heart from a brain-death donor (least-squares mean difference, -3 percentage points; 90% CI, -10 to 3; P<0.001 for noninferiority [margin, 20 percentage points]). There were no substantial between-group differences in the mean per-patient number of serious adverse events associated with the heart graft at 30 days after transplantation.

CONCLUSIONS

In this trial, risk-adjusted survival at 6 months after transplantation with a donor heart that had been reanimated and assessed with the use of extracorporeal nonischemic perfusion after circulatory death was not inferior to that after standard-care transplantation with a donor heart that had been preserved with the use of cold storage after brain death. (Funded by TransMedics; ClinicalTrials.gov number, NCT03831048.).

Epidemiology, Management, and Clinical Outcomes of Extrapulmonary Mycobacterium abscessus Complex Infections in Heart Transplant and Ventricular Assist Device Recipients

Nontuberculous mycobacteria (NTM) are emerging pathogens, yet data on the epidemiology and management of extrapulmonary NTM infections in orthotopic heart transplantation (OHT) and ventricular assist device (VAD) recipients are scarce. We retrospectively reviewed records of OHT and VAD recipients who underwent cardiac surgery at our hospital and developed Mycobacterium abscessus complex (MABC) infection from 2013-2016 during a hospital outbreak of MABC linked to heater-cooler units. We analyzed patient characteristics, medical and surgical management, and long-term outcomes. Ten OHT and 7 VAD patients developed extrapulmonary M. abscessus subspecies abscessus infection. Median time from presumed inoculation during cardiac surgery to first positive culture was 106 days in OHT and 29 days in VAD recipients. The most common sites of positive cultures were blood (n=12), sternum/mediastinum (n=8), and the VAD driveline exit site (n=7). The 14 patients diagnosed while alive received combination antimicrobial therapy for a median of 21 weeks, developed 28 antibiotic-related adverse events, and underwent 27 surgeries. Only 8 (47%) patients survived longer than 12 weeks after diagnosis, including 2 VAD patients who experienced long-term survival after explantation of infected VADs and OHT. Despite aggressive medical and surgical management, OHT and VAD patients with MABC infection experienced substantial morbidity and mortality.

The association with organ procurement techniques and early cardiac transplant outcomes using cardiac MRI

BACKGROUND

Heart transplantation (HT) has historically been limited by organ availability. Use of donation after circulatory death (DCD) donors addresses this limitation by utilizing previously unused hearts through use of the Organ Care System (OCS).

OBJECTIVES

This study aimed to determine the impact of procurement and transportation method on allograft structure and function using early post-transplant cardiac magnetic resonance imaging (MRI).

METHODS

Patients who underwent HT at our institution from February 1, 2020, through April 30, 2021 who underwent cardiac MRI imaging <60 days from transplant were included. Recipient and donor characteristics, clinical outcomes, and MRI findings were compared between those who underwent DCD transplantation using the OCS device (DCD-OCS), brain dead donation (DBD) using the OCS device (DBD-OCS), and DBD transported via cold storage (DBD-cold storage) using one-way analysis of variance.

RESULTS

A total of 85 patients underwent HT with a cardiac MRI during the study period. Thirty-one (36%) patients received a DCD organ, 16 (19%) received a DBD-OCS organ and 38 (45%) received a DBD-cold storage organ. Rates of primary graft dysfunction (PGD) were significantly higher in DCD transplants (19.5% DCD vs. .0% DBD-OCS and 5.3% DBD-cold storage; p < .050 across three groups), but with no differences in mortality or rejection. There were no differences in cardiac MRI findings between the three transplant types, including presence of gadolinium hyperenhancement after transplant (all p > .050).

CONCLUSIONS

We observed no differences in early cardiac MRI findings between patients that received DCD and DBD-OCS heart transplants compared with those receiving DBD-cold storage transplants.

Beyond Stage C: Considerations in the Management of Patients with Heart Failure Progression and Gaps in Evidence

Despite treatment with contemporary medical therapies for chronic heart failure (HF), there has been an increase in the prevalence of patients progressing to more advanced disease. Patients progressing to and living at the interface of severe Stage C and Stage D HF are underrepresented in clinical trials, and there is a lack of high-quality evidence to guide clinical decision making. For patients with a severe HF phenotype, the medical therapies used for patients with a less advanced stage of illness are often no longer tolerated nor provide adequate clinical stability. The limited data on these patients highlights the need to increase formal research characterizing this high-risk population. This review summarizes existing clinical trial data on and incorporates our considerations for approaches to the medical management of patients advanced "beyond Stage C" HF.

In-Hospital Virtual Peer-to-Peer Consultation to Increase Guideline-Directed Medical Therapy for Heart Failure: A Pilot Randomized Trial

BACKGROUND

Guideline-directed medical therapy (GDMT) for heart failure with reduced ejection fraction (HFrEF) improves clinical outcomes and quality of life. Optimizing GDMT in the hospital is associated with greater long-term use in HFrEF. This study aimed to describe the efficacy of a multidisciplinary virtual HF intervention on GDMT optimization among patients with HFrEF admitted for any cause.

METHODS

In this pilot randomized, controlled study, consecutive patients with HFrEF admitted to noncardiology medicine services for any cause were identified at a large academic tertiary care hospital between May to September 2021. Major exclusions were end-stage renal disease, hemodynamic instability, concurrent COVID-19 infection, and current enrollment in hospice care. Patients were randomized to a clinician-level virtual peer-to-peer consult intervention providing GDMT recommendations and information on medication costs versus usual care. Primary end points included (1) proportion of patients with new GDMT initiation or use and (2) changes to HF optimal medical therapy scores which included target dosing (range, 0-9).

RESULTS

Of 242 patients identified, 91 (38%) were eligible and randomized to intervention (N=52) or usual care (N=39). Baseline characteristics were similar between intervention and usual care (mean age 63 versus 67 years, 23% versus 26% female, 46% versus 49% Black, mean ejection fraction 33% versus 31%). GDMT use on admission was also similar. There were greater proportions of patients with GDMT initiation or continuation with the intervention compared with usual care. After adjusting for optimal medical therapy score on admission, changes to optimal medical therapy score at discharge were higher for the intervention group compared with usual care (+0.44 versus -0.31, absolute difference +0.75, adjusted estimate 0.86±0.42; P=0.041).

CONCLUSIONS

Among eligible patients with HFrEF hospitalized for any cause on noncardiology services, a multidisciplinary pilot virtual HF consultation increased new GDMT initiation and dose optimization at discharge.

Improved Outcomes in Severe Primary Graft Dysfunction After Heart Transplantation Following Donation After Circulatory Death Compared With Donation After Brain Death

BACKGROUND

Primary graft dysfunction (PGD), the leading cause of early mortality after heart transplantation, is more common following donation after circulatory death (DCD) than donation after brain death (DBD). We conducted a single-center, retrospective cohort study to compare the incidence, severity and outcomes of patients experiencing PGD after DCD compared to DBD heart transplantation.

METHODS AND RESULTS

Medical records were reviewed for all adult heart transplant recipients at our institution between March 2016 and December 2021. PGD was diagnosed within 24 hours after transplant according to modified International Society for Heart and Lung Transplant criteria. A total of 459 patients underwent isolated heart transplantation during the study period, 65 (14%) following DCD and 394 (86%) following DBD. The incidence of moderate or severe PGD in DCD and DBD recipients was 34% and 23%, respectively (P = 0.070). DCD recipients were more likely to experience severe biventricular PGD than DBD recipients (19% vs 7.4%; P = 0.004). Among patients with severe PGD, DCD recipients experienced shorter median (Q1, Q3) duration of post-transplant mechanical circulatory support (6 [4, 7] vs 9 [5, 14] days; P = 0.039), shorter median post-transplant hospital length of stay (17 [15, 29] vs 52 [26, 83] days; P = 0.004), and similar 60-day survival rates (100% [95% CI: 76.8%-100%] vs 80.0% [63.1%-91.6%]; P = 0.17) and overall survival (log-rank; P = 0.078) compared with DBD recipients.

CONCLUSIONS

DCD heart transplant recipients were more likely to experience severe, biventricular PGD than DBD recipients. Despite this, DCD recipients with severe PGD spent fewer days on mechanical circulatory support and in the hospital than similar DBD patients. These findings suggest that patterns of graft dysfunction and recovery may differ between donor types, and they support the expansion of the heart-donor pool with DCD.

The impact of race on utilization of durable left ventricular assist device therapy in patients with advanced heart failure

BACKGROUND

Heart failure affects >6 million people in the United States alone and is most prevalent in Black patients who suffer the highest mortality risk. Yet prior studies have suggested that Black patients are less likely to receive advanced heart failure therapy. We hypothesized that Black patients would have decreased rates of durable left ventricular assist device (LVAD) implantation within our expansive heart failure program.

METHODS

A retrospective single-center cohort study was conducted at a single high-volume academic medical center. Patients between 18 and 85 years admitted with a diagnosis of cardiogenic shock or congestive heart failure between 1, 2013 and 12, 2017 with a left ventricular ejection fraction < 30% and inotropic dependence or need for mechanical circulatory support were included. Patients with contraindications to durable LVAD were excluded. An adjusted logistic regression model for durable LVAD implantation within 90 days of the index admission was used to determine the effect of race on durable LVAD implantation.

RESULTS

Among the 702 study patients (60.9% White, 34.1% Black), durable LVAD implantation was performed within 90 days of the index admission in 183 (26%) of the cohort. After multivariate analysis, Black patients were not found to have a statistically significant difference in durable LVAD implantation rates compared to White patients in our study (OR: 0.68 [95% confidence interval: 0.45-1.04; p: .074]).

CONCLUSIONS

Black patients in our study did not have a statistically significant difference in the rate of durable LVAD implantation compared with White patients after adjustments were made for age, sex, socioeconomic, and clinical covariates. Larger prospective studies are needed to validate these findings.

Donation After Circulatory Death in Heart Transplantation: History, Outcomes, Clinical Challenges, and Opportunities to Expand the Donor Pool

Heart transplantation remains the gold-standard therapy for end-stage heart failure; the expected median survival range is 12-13 years. More than 30,000 heart transplants have been performed globally in the past decade alone. With advances in medical and surgical therapies for heart failure, including durable left ventricular assist devices, an increasing number of patients are living with end-stage disease. Last year alone, more than 2500 patients were added to the heart-transplant waitlist in the United States. Despite recent efforts to expand the donor pool, including an increase in transplantation of hepatitis C-positive and extended-criteria donors, supply continues to fall short of demand. Donation after circulatory death (DCD), defined by irreversible cardiopulmonary arrest rather than donor brain death, is widely used in other solid-organ transplants, including kidney and liver, but has not been widely adopted in heart transplantation. However, resurging interest in DCD donation and the introduction of ex vivo perfusion technology has catalyzed recent clinical trials and the development of DCD heart-transplantation programs. Herein, we review the history of DCD heart transplantation, describe the currently used procurement protocols for it and examine clinical challenges and outcomes of such a procedure.

Right and left ventricular assist devices are an option for bridge to heart transplant

Background

Patients with a left ventricular assist device with right ventricular failure are prioritized on the heart transplant waitlist; however, their post-transplant survival is less well characterized. We aimed to determine whether pretransplant right ventricular failure affects postoperative survival in patients with a left ventricular assist device as a bridge to transplant.

Methods

We performed a retrospective review of the 2005-2018 Organ Procurement and Transplantation Network/United Network for Organ Sharing registry for candidates aged 18 years or more waitlisted for first-time isolated heart transplantation after left ventricular assist device implantation. Candidates were stratified on the basis of having right ventricular failure, defined as the need for right ventricular assist device or intravenous inotropes. Baseline demographic and clinical characteristics were compared among the 3 groups, and post-transplant survival was assessed.

Results

Our cohort included 5605 candidates who met inclusion criteria, including 450 patients with right ventricular failure, 344 patients with a left ventricular assist device and intravenous inotropes as a bridge to transplant, 106 patients with a left ventricular assist device and right ventricular assist device, and 5155 patients with a left ventricular assist device as a bridge to transplant without the need for right side support. Compared with patients without right ventricular failure, patients with a left ventricular assist device as a bridge to transplant with right ventricular failure were younger (median age 51 years, 55 vs 56 years, P < .001) and waited less time for organs (median 51 days, 93.5 vs 125 days, P < .001). These patients also had longer post-transplant length of stay (median 18 days, 20 vs 16 days, P < .001). Right ventricular failure was not associated with decreased post-transplant long-term survival on unadjusted Kaplan–Meier analysis (P = .18). Neither preoperative right ventricular assist device nor intravenous inotropes independently predicted worse survival on multivariate Cox proportional hazards analysis. However, pretransplant liver dysfunction (total bilirubin >2) was an independent predictor of worse survival (hazard ratio, 1.74; 95% confidence interval, 1.39-2.17; P < .001), specifically in the left ventricular assist device group and not in the left ventricular assist device + right ventricular assist device/intravenous inotropes group.

Conclusions

Patients with biventricular failure are prioritized on the waiting list, because their critical pretransplant condition has limited impact on their post-transplant survival (short-term effect only); thus, surgeons should be confident to perform transplantation in these severely ill patients. Because liver dysfunction (a surrogate marker of right ventricular failure) was found to affect long-term survival in patients with a left ventricular assist device, surgeons should be encouraged to perform transplantation in these severely ill patients after a recipient's optimization by inotropes or a right ventricular assist device because even when the bilirubin level is elevated in these patients (treated with right ventricular assist device/inotropes), their long-term survival is not affected. Future studies should assess recipients' optimization before organ acceptance to improve long-term survival.

Polypharmacy in Palliative Care for Advanced Heart Failure: The PAL-HF Experience

BACKGROUND

Palliative care (PC) in advanced heart failure (HF) aims to improve symptoms and quality of life (QOL), in part through medication management. The impact of PC on polypharmacy (>5 medications) remains unknown.

METHODS AND RESULTS

We explored patterns of polypharmacy in the Palliative Care in HF (PAL-HF) randomized controlled trial of standard care vs interdisciplinary PC in advanced HF (N = 150). We describe differences in medication counts between arms at 2, 6, 12, and 24 weeks for HF (12 classes) and PC (6 classes) medications. General linear mixed models were used to evaluate associations between treatment arm and polypharmacy over time. The median age of the patients was 72 years (interquartile range 62-80 years), 47% were female, and 41% were Black. Overall, 48% had ischemic etiology, and 55% had an ejection fraction of 40% or less. Polypharmacy was present at baseline in 100% of patients. HF and PC medication counts increased in both arms, with no significant differences in counts by drug class at any time point between arms.

CONCLUSIONS

In a trial of patients with advanced HF considered eligible for PC, polypharmacy was universal at baseline and increased during follow-up with no effect of the palliative intervention on medication counts relative to standard care.

Pericardial Adipose Tissue Volume and Left Ventricular Assist Device-Associated Outcomes

BACKGROUND

Pericardial adipose tissue (PAT) is associated with adverse cardiovascular outcomes in those with and without established heart failure (HF). However, it is not known whether PAT is associated with adverse outcomes in patients with end-stage HF undergoing left ventricular assist device (LVAD) implantation. This study aimed to evaluate the associations between PAT and LVAD-associated outcomes.

METHODS AND RESULTS

We retrospectively measured computed tomography-derived PAT volumes in 77 consecutive adults who had available chest CT imaging prior to HeartMate 3 LVAD surgery between October 2015 and March 2019 at Duke University Hospital. Study groups were divided into above-median (≥219 cm³) and below-median (<219 cm³) PAT volume. Those with above-median PAT had a higher proportion of atrial fibrillation, chronic kidney disease and ischemic cardiomyopathy. Groups with above-median vs below-median PAT had similar Kaplan-Meier incidence rates over 2 years for (1) composite all-cause mortality, redo-LVAD surgery and cardiac transplantation (35.9 vs 32.2%; log-rank P = 0.65) and (2) composite incident hospitalizations for HF, gastrointestinal bleeding, LVAD-related infection, and stroke (61.5 vs 60.⁵%; log-rank P = 0.67).

CONCLUSIONS

In patients with end-stage HF undergoing LVAD therapy, PAT is not associated with worse 2-year LVAD-related outcomes. The significance of regional adiposity vs obesity in LVAD patients warrants further investigation.

Trends and Outcomes of Cardiac Transplantation in the Lowest Urgency Candidates

Background Due to discrepancies between donor supply and recipient demand, the cardiac transplantation process aims to prioritize the most medically urgent patients. It remains unknown how recipients with the lowest medical urgency compare to others in the allocation process. We aimed to examine differences in clinical characteristics, organ allocation patterns, and outcomes between cardiac transplantation candidates with the lowest and highest medical urgency. Methods and Results We performed a retrospective analysis of the United Network for Organ Sharing database. Patients listed for cardiac transplantation between January 2011 and May 2020 were stratified according to status at time of transplantation. Baseline recipient and donor characteristics, waitlist survival, and post-transplantation outcomes were compared in the years before and after the 2018 allocation system change. Lower urgency patients in the old system were older (58.5 vs. 56 years) and more likely female (54.4% vs. 23.8%) compared to the highest urgency patients, and these trends persisted in the new system (p<0.001, all). Donors for the lowest urgency patients were more likely older, female, or have a history of CMV, hepatitis C, or diabetes (p<0.01, all). The lowest urgency patients had longer waitlist times, and under the new allocation system received organs from shorter distances with decreased ischemic times (178 vs. 269 miles, 3.1 vs 3.5 hours, p<0,001, all). There was no difference in post-transplantation survival (p<0.01, all). Conclusions Patients transplanted as lower urgency receive hearts from donors with additional comorbidities compared to higher urgency patients, but outcomes are similar at one year.

Innovations in Heart Transplantation: A Review

Advanced heart failure affects tens of thousands of people in the United States alone with high morbidity and mortality. Cardiac transplantation offers the best treatment strategy but has been historically limited by donor availability. Recently, there have been significant advances in organ allocation, donor-recipient matching, organ preservation and expansion of the donor pool. The current heart allocation system prioritizes the sickest patients to minimize waitlist mortality. Advances in donor organ selection including predicted heart mass calculations and more sophisticated antibody detection methods for allosensitized patients offer more effective matching of donors and recipients. Innovations in organ preservation such as with organ preservation systems have geographically widened the donor pool. The use of hepatitis C donors is possible with the advent of effective direct-acting antiviral agents to cure donor-transmitted hepatitis C. Finally, further expansion of the donor pool is occurring with the utilization of higher-risk donors with advanced age, medical comorbidities, and left ventricular dysfunction and advances in donation after circulatory death. This review provides an update on the new technologies and transplantation strategies that serve to widen the donor pool and more effectively match donors and recipients so that heart transplant candidates may derive the best outcomes from heart transplantation.

EXPANDing the Donor Pool: Quantifying the Potential Impact of a Portable Organ-Care System for Expanded Criteria Heart Donation

The recently concluded prospective Portable Organ Care System (OCS) Heart trial to Evaluate the Safety and Effectiveness of The Portable Organ Care System Heart for Preserving and Assessing Expanded Criteria Donor Hearts for Transplantation (EXPAND) demonstrated that the use of ex vivo perfusion for expanded-criteria hearts may be a viable method for increasing the use of donor hearts. We sought to estimate the potential impact of ex vivo expanded-criteria heart perfusion on the donor pool in the United States by using a large national transplant registry. After applying the inclusion criteria of EXPAND, 8637 potentially eligible donors were identified in the U.S. between January 1, 2015, and June 30, 2019, representing a substantial potential increase in the donor pool.

Proteomic profiling identifies CLEC4C expression as a novel biomarker of primary graft dysfunction after heart transplantation

PURPOSE

Clinical models to identify patients at high risk of primary graft dysfunction (PGD) after heart transplantation (HT) are limited, and the underlying pathophysiology of this common post-transplant complication remains poorly understood. We sought to identify whether pre-transplant levels of circulating proteins reporting on immune activation and inflammation are associated with incident PGD.

METHODS

The study population consisted of 219 adult heart transplant recipients identified between 2016 and 2020 at Duke University Medical Center, randomly divided into derivation (n = 131) and validation (n = 88) sets. PGD was defined using modified ISHLT criteria. Proteomic profiling was performed using Olink panels (n = 354 proteins) with serum samples collected immediately prior to transplantation. Association between normalized relative protein expression and PGD was tested using univariate and multivariable (recipient age, creatinine, mechanical circulatory support, and sex; donor age; ischemic time) models. Significant proteins identified in the derivation set (p < 0.05 in univariate models), were then tested in the validation set. Pathway enrichment analysis was used to test candidate biological processes. The predictive performance of proteins was compared to that of the RADIAL score.

RESULTS

Nine proteins were associated with PGD in univariate models in the derivation set. Of these, only CLEC4C remained associated with PGD in the validation set after Bonferroni correction (OR [95% CI] = 3.04 [1.74,5.82], p = 2.8 × 10^-4). Patterns of association were consistent for CLEC4C in analyses stratified by biventricular/left ventricular and isolated right ventricular PGD. Pathway analysis identified interferon-alpha response and C-type lectin signaling as significantly enriched biologic processes. The RADIAL score was a poor predictor of PGD (AUC = 0.55). CLEC4C alone (AUC = 0.66, p = 0.048) and in combination with the clinical covariates from the multivariable model (AUC = 0.69, p = 0.018) improved discrimination for the primary outcome.

CONCLUSIONS

Pre-transplantation circulating levels of CLEC4C, a protein marker of plasmacytoid dendritic cells (pDCs), may identify HT recipients at risk for PGD. Further studies are needed to better understand the potential role pDCs and the innate immune response in PGD.

A Case for Re-Gifting

Many patients die while waiting for a heart transplant. Therefore, it is vital that all suitable organs are used for transplantation. We present a case of an allograft that was transplanted twice and outline considerations regarding tissue typing, the impact of repeated ischemic time, and ethical considerations with allograft retransplantation. (Level of Difficulty: Intermediate.)

Electrical storm in patients with left ventricular assist devices: Risk factors, incidence, and impact on survival

BACKGROUND

Ventricular arrhythmias (VAs) and electrical storm (ES) are recognized complications following left ventricular assist device (LVAD) implantation; however, their association with long term-outcomes remains poorly understood.

OBJECTIVE

The purpose of this study was to describe the clinical impact of ES in a population of patients undergoing LVAD implantation at a quaternary care center in the United States.

METHODS

This was an observational retrospective study of patients undergoing LVAD implantation from 2009 to 2020 at Duke University Hospital. The incidence of ES (≥3 sustained VA episodes over a 24-hour period without an identifiable reversible cause) was determined from patient records. Risk factors for ES were identified using multivariable Cox proportional hazards modeling.

RESULTS

Among 730 patients undergoing LVAD implant, 78 (10.7%) developed ES at a median of 269 (interquartile range [IQR] 7-766) days following surgery. Twenty-seven patients (34.6%) developed ES within 30 days, while 51 (65.4%) presented with ES at a median 639 (IQR 281-1017) days after implant. Following ES, 41% of patients died within 1 year. Patients who developed ES were more likely to have a history of VAs, ventricular tachycardia ablation, antiarrhythmic drug use, and perioperative mechanical circulatory support around the time of LVAD implant than patients without ES.

CONCLUSION

ES occurs in 1 in 10 patients after LVAD and is associated with higher mortality. Risk factors for ES include a history of VAs, VT ablation, antiarrhythmic drug use, and perioperative mechanical circulatory support. Optimal management of ES surrounding LVAD implant, including escalation of medical therapy, catheter ablation, or adjunctive sympatholytic therapies, remains uncertain.

Splanchnic Nerve Block Mediated Changes in Stressed Blood Volume in Heart Failure

OBJECTIVES

The authors estimated changes of stressed blood volume (SBV) induced by splanchnic nerve block (SNB) in patients with either decompensated or ambulatory heart failure with reduced ejection fraction (HFrEF).

BACKGROUND

The splanchnic vascular capacity is a major determinant of the SBV, which in turn determines cardiac filling pressures and may be modifiable through SNB.

METHODS

We analyzed data from 2 prospective, single-arm clinical studies in decompensated HFrEF (splanchnic HF-1; resting hemodynamics) and ambulatory heart failure (splanchnic HF-2; exercise hemodynamics). Patients underwent invasive hemodynamics and short-term SNB with local anesthetics. SBV was simulated using heart rate, cardiac output, central venous pressure, pulmonary capillary wedge pressure, systolic and diastolic systemic arterial and pulmonary artery pressures, and left ventricular ejection fraction. SBV is presented as ml/70 kg body weight.

RESULTS

Mean left ventricular ejection fraction was 21 ± 11%. In patients with decompensated HFrEF (n = 11), the mean estimated SBV was 3,073 ± 251 ml/70 kg. At 30 min post-SNB, the estimated SBV decreased by 10% to 2,754 ± 386 ml/70 kg (p = 0.003). In ambulatory HFrEF (n = 14) patients, the mean estimated SBV was 2,664 ± 488 ml/70 kg and increased to 3,243 ± 444 ml/70 kg (p < 0.001) at peak exercise. The resting estimated SBV was lower in ambulatory patients with HFrEF than in decompensated HFrEF (p = 0.019). In ambulatory patients with HFrEF, post-SNB, the resting estimated SBV decreased by 532 ± 264 ml/70 kg (p < 0.001). Post-SNB, with exercise, there was no decrease of estimated SBV out of proportion to baseline effects (p = 0.661).

CONCLUSIONS

The estimated SBV is higher in decompensated than in ambulatory heart failure. SNB reduced the estimated SBV in decompensated and ambulatory heart failure. The reduction in estimated SBV was maintained throughout exercise. (Splanchnic Nerve Anesthesia in Heart Failure, NCT02669407; Abdominal Nerve Blockade in Chronic Heart Failure, NCT03453151).

Decision Aid Implementation among Left Ventricular Assist Device Programs Participating in the DECIDE-LVAD Stepped-Wedge Trial

Background. Despite demonstrated efficacy, patient decision aids (DAs) are rarely used in clinical practice in the absence of coverage mandates. Deciding whether to pursue a left ventricular assist device (LVAD) is a major, preference-sensitive decision-ideal for exploring implementation of a DA. Methods. We conducted a type II effectiveness-implementation hybrid trial at 6 LVAD programs using a stepped-wedge cluster-randomized design. Using the RE-AIM framework, we collected both quantitative and qualitative outcomes, including a checklist collected by study staff for each enrolled patient regarding DA use and interviews with LVAD program clinicians preintervention, 6 months postintervention, and at the conclusion of the study. Results. From June 2015 to January 2017, 248 patients and their caregivers were enrolled. A total of 69 interviews were conducted with 48 clinicians at 3 time points. The DA reached 95% of eligible patients. Adoption was 100%, as all sites approached agreed to participate in the trial. Interviews revealed several themes related to the implementation of the DA: clinicians had a strong desire to ensure patients were informed and embraced the DA. Despite this, they reported communication challenges among their team that impeded implementation. Five of the 6 sites have maintained use of the DA following the trial; 1 site reported concerns about decreased procedural volume with use of the DA as a reason for discontinuation. Conclusions. In this hybrid trial, a DA for patients considering LVADs and their caregivers demonstrated high reach. Adoption and implementation were facilitated by a strong desire to ensure that patients were well informed. Future dissemination research and practice should attend to concerns about procedure volume and coverage mandates and facilitate ongoing communication at sites using the DA.

Transplant Center Variability in Organ Offer Acceptance and Mortality Among US Patients on the Heart Transplant Waitlist

Importance

Under the current Centers for Medicare & Medicaid Services guidelines, there is incentivization to optimize posttransplant outcomes regardless of mortality among patients on the waitlist and transplant rates; few data exist with regard to transplant center acceptance practices and survival to heart transplant.

Objectives

To evaluate the extent of variability in organ acceptance practices in the US and whether this center-level behavior is associated with heart transplant candidate survival.

Design, Setting, and Participants

In this retrospective cohort study, the US National Transplant Registry was queried for all match runs of adult candidates listed for isolated heart transplant between May 1, 2007, and March 31, 2017. Data analysis was conducted from October 30, 2018, to May 1, 2019. The final cohort included 93 transplant centers, 19 703 donors, and 9628 candidates.

Main Outcomes and Measures

Center acceptance rates for heart allografts offered to the highest-priority candidates, association between center acceptance rate and mortality among patients on the waitlist, and posttransplant outcomes between candidates who accepted their first-rank offers vs those who accepted previously declined offers.

Results

Among 19 703 unique organ offers, 6302 hearts (32.0%) were accepted for first-rank candidates. After adjustment for donor, candidate, and geographic covariates, transplant centers varied in acceptance rates (12.3%-61.5%) of offers made to first-rank candidates. Higher acceptance rates were associated with lower cumulative incidence of 1-year mortality among patients on the waitlist. For every 10% increase in adjusted center acceptance rate, the risk of mortality decreased by 27% (subdistribution hazard ratio, 0.73; 95% CI, 0.67-0.80). No statistically significant difference was observed in 5-year adjusted posttransplant patient survival (adjusted hazard ratio, 1.02; 95% CI, 0.94-1.11) and graft failure (subdistribution hazard ratio; 0.95; 95% CI, 0.83-1.09) between hearts accepted at the first-rank compared with lower-rank positions.

Conclusions and Relevance

Variability in heart allograft acceptance rates appears to exist among transplant centers, with candidates listed at lower acceptance rate centers being more likely to experience mortality while on the waitlist. Comparable posttransplant survival suggests that allografts that were declined as a first offer perform as well as those that were accepted at their first offer. These findings suggest that organ acceptance rate or time to transplant from being added to the waitlist may be an additional measure of heart transplant program performance.

Assessment of Limitations to Optimization of Guideline-Directed Medical Therapy in Heart Failure From the GUIDE-IT Trial: A Secondary Analysis of a Randomized Clinical Trial

Importance

Despite evidence that guideline-directed medical therapy (GDMT) improves outcomes in patients with heart failure (HF) and reduced ejection fraction, many patients are undertreated. The Guiding Evidence-Based Therapy Using Biomarker Intensified Treatment (GUIDE-IT) trial tested whether a strategy of using target concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP) to guide optimization of GDMT could improve outcomes.

Objective

To examine medical therapy for HF in GUIDE-IT and potential reasons why the intervention did not produce improvements in medical therapy.

Design, Setting, and Participants

GUIDE-IT, a randomized clinical trial performed at 45 sites in the United States and Canada, was conducted from January 16, 2013, to September 20, 2016. A total of 894 patients with HF and reduced ejection fraction (≤40%) were randomized to NT-proBNP-guided treatment with a goal to suppress NT-proBNP concentrations to less than 1000 pg/mL vs usual care. This secondary analysis examined the medical therapy titration and reasons why the intervention did not produce improvements in care and outcomes. Data were analyzed March 27 to June 28, 2019.

Main Outcomes and Measures

For each encounter, medication titrations were captured. A reason was requested if a modification was not made. A Cox proportional hazards regression model was used to assess the independent association of drug class with outcomes.

Results

Among the 838 patients available for analysis (566 men [67.5%]; median age, 62.0 years), 6223 visits occurred during 24 months. Adjustments of HF medication were made during 2847 of 5218 qualified visits (54.6%) (all usual care visits and all guided care visits with NT-proBNP level ≥1000 pg/mL) in 862 patients (96.4%). Most adjustments occurred within the first 6 months, primarily within the first 6 weeks. The most common reasons for not adjusting were "clinically stable" and "already at maximally tolerated therapy." Only 130 patients (15.5%) achieved optimal GDMT (≥50% of the target dose of β-blockers or angiotensin-converting enzyme inhibitors/angiotensin receptor blockers or any dose of mineralocorticoid antagonists) at 6 months, an increase from the baseline (79 of 891 [8.9%]) but not different by treatment arm. Higher doses of β-blockers were associated with reduced risk of the composite outcome of HF hospitalization and cardiovascular death (hazard ratio [HR], 0.98; 95% CI, 0.97-1.00; P = .008) and of all-cause death (HR, 0.97; 95% CI, 0.95-0.99; P = .01). Higher doses of angiotensin-converting enzyme inhibitors (HR, 0.84; 95% CI, 0.75-0.93; P < .001) and angiotensin receptor blockers (HR, 0.84; 95% CI, 0.71-0.99; P = .04) were associated with reduced risk of all-cause death. Increasing doses of mineralocorticoid antagonists did not appear to be associated with improved outcomes.

Conclusions and Relevance

Despite a protocol-driven approach, many patients in GUIDE-IT did not receive medication adjustments and did not achieve optimal GDMT, including those with known elevated NT-proBNP concentrations. These results suggest that opportunities exist to titrate medications for maximal benefit in HF. GUIDE-IT may have failed to achieve treatment benefit because of therapeutic inertia in clinical practice, or current GDMT goals may be unrealistic.

Trial Registration

ClinicalTrials.gov Identifier: NCT01685840.

Mitigating the Impact of Using Female Donor Hearts in Male Recipients Using BMI Difference

BACKGROUND

Heart transplantation is limited by the supply of donor organs. Previous studies have associated female donor to male recipient with decreased posttransplant survival. We wanted to evaluate whether this risk can be mitigated using higher donor than recipient body mass index (BMI).

METHODS

We performed a retrospective analysis of the Organ Procurement and Transplantation Network/United Network of Organ Sharing registry encompassing years 2005 to 2018 for all male adult recipients (>18 years of age) who underwent isolated heart transplantation with grafts from female donors. The association between donor and recipient BMI difference and recipient survival was evaluated using adjusted Cox proportional hazards modeling.

RESULTS

A total of 3788 male recipients who received female donor hearts met inclusion criteria for analysis. Maximally selected rank statistics identified donor minus recipient BMI of 1.5 kg/m² as a meaningful cutoff point in the analysis of recipient survival. Multivariable Cox proportional hazards analysis demonstrated that increasing donor BMI relative to recipient BMI up to this cutoff point was associated with improved survival (hazard ratio per 5-unit difference, 0.87; 95% confidence interval, 0.77-0.99). Above this cutoff point, increasing donor BMI relative to the recipient did not improve survival more than what was achieved by adding 1.5 of BMI difference (hazard ratio per 5-unit difference, 0.97; 95% confidence interval, 0.90-1.04).

CONCLUSIONS

Increasing donor BMI relative to recipient BMI up to 1.5 kg/m² greater than recipient BMI was associated with improved survival. BMI difference may be useful as a simple surrogate for predicted heart mass difference to help mitigate the impact of sex mismatch in heart transplantation.

Cardiac computed tomography improves the identification of cardiomechanical complications among patients with suspected left ventricular assist device malfunction

BACKGROUND

Left ventricular assist devices (LVAD) are increasingly used for durable mechanical circulatory support in advanced heart failure. While LVAD therapy provides substantial improvement in mortality and quality of life, long-term therapy confers increased risk for device complications. We evaluated if cardiac computed tomography (CCT) improves the detection of cardiomechanical complications among patients with LVAD and suspected device malfunction.

METHODS

In this study, we compared the diagnostic performance of CCT and transthoracic echocardiography (TTE) for the identification of cardiomechanical LVAD complications, including thrombus or neointimal hyperplasia, inflow cannula malposition with dynamic obstruction, fixed outflow obstruction, device infection, and severe aortic regurgitation. Complications were confirmed with surgical evaluation, pathologic assessment, or response to therapeutic intervention.

RESULTS

Among 58 LVAD patients, who underwent CCT and TTE for suspected LVAD dysfunction, there were 49 confirmed cardiomechanical LVAD complications among 43 (74.1%) patients. The most common LVAD complication was thrombus or neointimal hyperplasia (65.3%), followed by dynamic obstruction (26.5%). Individually, CCT identified 29 of the 49 (59.2%) confirmed LVAD cardiomechanical complications, whereas TTE alone identified a complication in 11 cases (22.4%). However, diagnostic performance was greatest when the two modalities were used in combination, yielding a sensitivity of 67%, specificity of 93%, PPV of 97%, NPV of 47% and diagnostic accuracy of 73%.

CONCLUSION

The novel and complementary use of CCT with TTE for the evaluation of suspected device malfunction improves the accurate identification of cardiomechanical LVAD complication compared to either modality alone.

Biomarkers in Advanced Heart Failure: Implications for Managing Patients With Mechanical Circulatory Support and Cardiac Transplantation

Biomarkers have a well-defined role in the diagnosis and management of chronic heart failure, but their role in patients with left ventricular assist devices and cardiac transplant is uncertain. In this review, we summarize the available literature in this patient population, with a focus on clinical application. Some ubiquitous biomarkers, for example, natriuretic peptides and cardiac troponin, may assist in the diagnosis of left ventricular assist device complications and transplant rejection. Novel biomarkers focused on specific pathological processes, such as left ventricular assist device thrombosis and profiling of leukocyte activation, continue to be developed and show promise in altering the management of the advanced heart failure patient. Few biomarkers at this time have been assessed with sufficient scrutiny to warrant broad, universal application, but encouraging limited data and large potential for impact should prompt ongoing investigation.

PredischaRge initiation of Ivabradine in the ManagEment of Heart Failure: Results of the PRIME-HF Trial

BACKGROUND

Ivabradine is guideline-recommended to reduce heart failure (HF) hospitalization in patients with stable chronic HF with reduced ejection fraction (EF). Ivabradine initiation following acute HF has had limited evaluation, and there are few randomized data in US patients. The PredischaRge initiation of Ivabradine in the ManagEment of Heart Failure (PRIME-HF) study was conducted to address predischarge ivabradine initiation in stabilized acute HF patients.

METHODS

PRIME-HF was an investigator-initiated, randomized, open-label study of predischarge initiation of ivabradine versus usual care. Eligible patients were hospitalized for acute HF but stabilized, with EF ≤35%, on maximally tolerated β-blocker and in sinus rhythm with heart rate ≥70 beats/min. Ivabradine was acquired per routine care. The primary end point was the proportion of patients on ivabradine at 180 days. Additional end points included heart rate change, patient-reported outcomes, β-blocker use/dose, and safety events (symptomatic bradycardia and hypotension).

RESULTS

Overall, 104 patients (36% women, 64% African American) were randomized, and the study was terminated early because of funding limitations. At 180 days, 21 of 52 (40.4%) of patients randomized to predischarge initiation were treated with ivabradine compared with 6 of 52 (11.5%) randomized to usual care (odds ratio 5.19, 95% CI 1.88-14.33, P = .002). The predischarge initiation group experienced greater reduction in heart rate through 180 days (mean -10.0 beats/min, 95% CI -15.7 to -4.3 vs 0.7 beats/min, 95% CI -5.4 to 6.7, P = .011). Patient-reported outcomes, β-blocker use/dose, and safety events were similar (all P > .05).

CONCLUSIONS

Ivabradine initiation prior to discharge among stabilized HF patients increased ivabradine use at 180 days and lowered heart rates without reducing β-blockers or increasing adverse events. As the trial did not achieve the planned enrollment, additional studies are needed.

Sex Differences in Quality of Life and Clinical Outcomes in Patients With Advanced Heart Failure: Insights From the PAL-HF Trial

BACKGROUND

Palliative care improves quality of life in patients with heart failure. Whether men and women with heart failure derive similar benefit from palliative care interventions remains unknown.

METHODS

In a secondary analysis of the PAL-HF trial (Palliative Care in Heart Failure), we analyzed differences in quality of life among men and women with heart failure and assessed for differential effects of the palliative care intervention by sex. Differences in clinical characteristics and quality-of-life metrics were compared between men and women at serial time points. The primary outcome was change in Kansas City Cardiomyopathy Questionnaire score between baseline and 24 weeks.

RESULTS

Among the 71 women and 79 men, there was a significant difference in baseline Kansas City Cardiomyopathy Questionnaire (24.5 versus 36.2, respectively; P=0.04) but not Functional Assessment of Chronic Illness Therapy-Palliative Care scale (115.7 versus 120.3; P=0.27) scores. Among those who received the palliative care intervention (33 women and 42 men), women's quality-of-life score remained lower than that of men after enrollment. Treated men's scores were significantly higher than those untreated (6-month Kansas City Cardiomyopathy Questionnaire, 68.0 [interquartile range, 52.6-85.7] versus 41.1[interquartile range, 32.0-78.3]; P=0.047), whereas the difference between treated and untreated women was not significantly different (P=0.39). Rates of death and rehospitalization, as well as the composite end point, were similar between treated and untreated women and men.

CONCLUSIONS

In the PAL-HF trial, women with heart failure experienced a greater symptom burden and poorer quality of life as compared with men. The change in treated men's Kansas City Cardiomyopathy Questionnaire score between baseline and 24 weeks was significantly higher than those untreated; this trend was not observed in women. Thus, there may be a sex disparity in response to palliative care intervention, suggesting that sex-specific approaches to palliative care may be needed to improve outcomes. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT0158960.

Influence of donor brain death duration on outcomes following heart transplantation: A United Network for Organ Sharing Registry analysis

OBJECTIVES

We hypothesized that an increased duration of donor brain death may worsen survival following orthotopic heart transplantation.

METHODS

The United Network for Organ Sharing Registry was queried for first-time, adult recipients of heart transplant from 2006 to 2018. Cox proportional hazards with penalized smooth splines was used to stratify patients based on donor brain death interval: shorter (<22 hours), reference (22-42 hours), and longer (>42 hours). Overall survival was estimated using Kaplan-Meier and Cox proportional hazards models.

RESULTS

A total of 22,960 patients met study criteria (9.2% shorter, 55.0% reference, and 35.8% longer). Longer brain death duration recipients were more likely to have a later year of transplant and have a mechanical bridge to transplant, whereas longer duration donors were more likely to be black and die of anoxia compared with shorter duration and reference donors. Compared with reference, neither shorter (hazard ratio, 1.02; 95% confidence interval, 0.94-1.12) nor longer donor brain death interval (hazard ratio, 1.01; 95% CI, 0.94-1.08) was associated with posttransplant survival in either unadjusted or multivariable analyses (both P values >0.6).

CONCLUSIONS

Longer duration of brain death was not associated with worse survival following heart transplantation. Donors with prolonged interval of brain death should not necessarily be excluded based on brain death period alone.

Stellate Ganglion Blockade for the Treatment of Refractory Ventricular Arrhythmias

OBJECTIVES

This study sought to describe our institutional experience with establishing a neurocardiology service in an attempt to provide autonomic modulation as a treatment for ventricular arrhythmias (VAs).

BACKGROUND

Treatment-refractory VAs are commonly driven and exacerbated by heightened sympathetic tone.

METHODS

Among patients referred to the neurocardiology service (August 2016 to December 2018), we performed ultrasound-based, bilateral, temporary stellate ganglion blockade (SGB) in 20 consecutive patients. We analyzed outcomes of interest including sustained VA or VA requiring defibrillation in the 24 and 48 h before and 24 and 48 h after SGB.

RESULTS

The majority of patients were men (n = 19, 95%), with a mean age of 58 ± 14 years. At the time of SGB, 10 (50%) were on inotropic support and 9 (45%) were on mechanical circulatory support. Besides 1 case of hoarseness, there were no apparent procedural complications. SGB was associated with a reduction in the number of VA episodes from the 24 h before (median 5.5 [interquartile range (IQR): 2.0 to 15.8]) to 24 h after SGB (median 0 [IQR: 0 to 3.8]) (p < 0.001). The number of defibrillation events decreased from 2.5 (IQR: 0 to 10.3) to 0 (IQR: 0 to 2.5) (p = 0.002). Similar findings were observed over the 48-h period before and after the SGB. Overall, 9 of 20 (45%) patients had a complete response with no recurrence of ventricular tachycardia (VT) or ventricular fibrillation (VF) for 48 h after SGB. Four (20%) patients had no recurrent VT or VF following SGB through discharge. Similar response rates were observed in those with ischemic (median 6 [IQR: 1.8 to 18.8] to 0.5 [IQR: 0 to 5.3] events; p = 0.031) and nonischemic (median 3.5 [IQR: 1.8 to 6.8] to 0 [IQR: 0 to 1.3] events; p = 0.012) cardiomyopathy.

CONCLUSIONS

Minimally invasive, ultrasound-guided bilateral SGB appears safe and provides substantial reduction in VA burden with approximately 1 in 2 patients exhibiting complete suppression of VT or VF for 48 h.

Renal Outcomes in Patients Bridged to Heart Transplant With a Left Ventricular Assist Device

BACKGROUND

Patients with end-stage heart failure are increasingly being bridged to heart transplant (BTT) with mechanical circulatory support; however the association between a left ventricular assist device (LVAD) BTT strategy and posttransplant renal outcomes is unclear. The aim of this study was to analyze the association of LVAD BTT with the development of posttransplant renal failure using a large national registry.

METHODS

We queried the 2009 to 2018 United Network for Organ Sharing registry for all adults undergoing first-time heart or heart-kidney transplantation and stratified patients by use of pretransplant durable LVAD. The primary outcome of interest was posttransplant renal failure, which was evaluated with multivariable logistic regression.

RESULTS

Of 18,307 patients meeting inclusion criteria, 7887 were (43%) and 10,420 were not (57%) BTT with an LVAD. BTT patients had slightly better baseline renal function (estimated glomerular filtration rate, 68.7 vs 65.8 mL/min, P < .001) and were less likely to receive a heart-kidney transplant (2.7% vs 4.8%, P < .001). On multivariable logistic regression, LVAD BTT strategy was not independently associated with posttransplant renal failure (odds ratio, 1.13; 95% confidence interval, 0.86-1.49). Similarly LVAD BTT among patients with preoperative renal dysfunction was not associated with posttransplant renal failure (adjusted odds ratio, 1.40; 95% confidence interval, 0.91-2.18).

CONCLUSIONS

BTT with an LVAD does not appear to be associated with worse renal outcomes regardless of baseline renal function. Furthermore, an LVAD BTT strategy in patients with chronic kidney disease may enable clinicians to identify candidates suitable for isolated heart transplantation without increasing their risk for posttransplant renal failure.

Best Practices for Prognostic Evaluation of a Patient With Transthyretin Amyloid Cardiomyopathy

Transthyretin amyloid cardiomyopathy (ATTR-CM) has emerged as an increasingly identified etiology of heart failure. Fortunately, the disease now has an approved therapy, with many others under development. Assessment of prognosis in ATTR-CM is critical to inform patients about the disease course and guide clinical decisions. This review discusses the evidence behind clinical, biomarker, and imaging findings that inform prognosis in patients with ATTR-CM and can assist providers in the shared decision-making process during management of this disease.

•

Prognostic factors for ATTR-CM can guide patient expectations and inform clinical decisions.

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Clinical features, blood biomarkers, and imaging obtained during workup for ATTR-CM convey prognostic information.

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Further studies in determining the incremental value of prognostic factors are warranted.

Durability and Efficacy of Tricuspid Valve Repair in Patients Undergoing Left Ventricular Assist Device Implantation

OBJECTIVES

This study sought to determine the durability of tricuspid valve repair (TVr) performed concurrently with left ventricular assist device (LVAD) implantation and its association with the development of late right heart failure (RHF).

BACKGROUND

Surgical management of tricuspid regurgitation (TR) at the time of LVAD implantation is performed in an attempt to reduce the occurrence of postoperative RHF. Limited data exist regarding the durability of TVr in patients with LVAD as well as its impact on development of late RHF.

METHODS

A retrospective review was conducted of consecutive adult patients who underwent durable LVAD implantation and concurrent TVr at the authors' institution between 2009 and 2017. Late RHF was defined as readmission for HF requiring inotropic or diuretic therapy. TVr failure was defined as moderate or severe TR at any follow-up echocardiographic examination after LVAD implantation.

RESULTS

A total of 156 patients underwent LVAD and concurrent TVr during the study. Of the total, 59 patients (37.8%) had a failed TVr. The mean duration of echocardiographic follow-up was 23 ± 22 months. Of the 146 patients who were discharged after the index hospitalization, 53 patients (36.3%) developed late RHF. Multivariate Cox proportional hazard analysis demonstrated that TVr failure was an independent predictor of late RHF development (hazard ratio: 2.62; 95% confidence interval: 1.38 to 4.96; p = 0.003).

CONCLUSIONS

Failure of TVr in this cohort occurred at a significant rate. Failure of TVr is an independent risk factor for development of late RHF. Future studies should investigate strategies to reduce recurrence of significant TR.