Racial Differences in Donor-Derived Cell-Free DNA and Mitochondrial DNA After Heart Transplantation, on Behalf of the GRAfT Investigators

BACKGROUND

Black heart transplant patients are at higher risk of acute rejection (AR) and death than White patients. We hypothesized that this risk may be associated with higher levels of donor-derived cell-free DNA (dd-cfDNA) and cell-free mitochondrial DNA.

METHODS

The Genomic Research Alliance for Transplantation is a multicenter, prospective, longitudinal cohort study. Sequencing was used to quantitate dd-cfDNA and polymerase chain reaction to quantitate cell-free mitochondrial DNA in plasma. AR was defined as ≥2R cellular rejection or ≥1 antibody-mediated rejection. The primary composite outcome was AR, graft dysfunction (left ventricular ejection fraction <50% and decrease by ≥10%), or death.

RESULTS

We included 148 patients (65 Black patients and 83 White patients), median age was 56 years and 30% female sex. The incidence of AR was higher in Black patients compared with White patients (43% versus 19%; P=0.002). Antibody-mediated rejection occurred predominantly in Black patients with a prevalence of 20% versus 2% (P<0.001). After transplant, Black patients had higher levels of dd-cfDNA, 0.09% (interquartile range, 0.001-0.30) compared with White patients, 0.05% (interquartile range, 0.001-0.23; P=0.003). Beyond 6 months, Black patients showed a persistent rise in dd-cfDNA with higher levels compared with White patients. Cell-free mitochondrial DNA was higher in Black patients (185 788 copies/mL; interquartile range, 101 252-422 133) compared with White patients (133 841 copies/mL; interquartile range, 75 346-337 990; P<0.001). The primary composite outcome occurred in 43% and 55% of Black patients at 1 and 2 years, compared with 23% and 27% in White patients, P<0.001. In a multivariable model, Black patient race (hazard ratio, 2.61 [95% CI, 1.35-5.04]; P=0.004) and %dd-cfDNA (hazard ratio, 1.15 [95% CI, 1.03-1.28]; P=0.010) were associated with the primary composite outcome.

CONCLUSIONS

Elevated dd-cfDNA and cell-free mitochondrial DNA after heart transplant may mechanistically be implicated in the higher incidence of AR and worse clinical outcomes in Black transplant recipients.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02423070.

Efficacy and Safety of Acoramidis in Transthyretin Amyloid Cardiomyopathy

BACKGROUND

Transthyretin amyloid cardiomyopathy is characterized by the deposition of misfolded monomeric transthyretin (TTR) in the heart. Acoramidis is a high-affinity TTR stabilizer that acts to inhibit dissociation of tetrameric TTR and leads to more than 90% stabilization across the dosing interval as measured ex vivo.

METHODS

In this phase 3, double-blind trial, we randomly assigned patients with transthyretin amyloid cardiomyopathy in a 2:1 ratio to receive acoramidis hydrochloride at a dose of 800 mg twice daily or matching placebo for 30 months. Efficacy was assessed in the patients who had an estimated glomerular filtration rate of at least 30 ml per minute per 1.73 m2 of body-surface area. The four-step primary hierarchical analysis included death from any cause, cardiovascular-related hospitalization, the change from baseline in the N-terminal pro-B-type natriuretic peptide (NT-proBNP) level, and the change from baseline in the 6-minute walk distance. We used the Finkelstein-Schoenfeld method to compare all potential pairs of patients within strata to generate a P value. Key secondary outcomes were death from any cause, the 6-minute walk distance, the score on the Kansas City Cardiomyopathy Questionnaire-Overall Summary, and the serum TTR level.

RESULTS

A total of 632 patients underwent randomization. The primary analysis favored acoramidis over placebo (P<0.001); the corresponding win ratio was 1.8 (95% confidence interval [CI], 1.4 to 2.2), with 63.7% of pairwise comparisons favoring acoramidis and 35.9% favoring placebo. Together, death from any cause and cardiovascular-related hospitalization contributed more than half the wins and losses to the win ratio (58% of all pairwise comparisons); NT-proBNP pairwise comparisons yielded the highest ratio of wins to losses (23.3% vs. 7.0%). The overall incidence of adverse events was similar in the acoramidis group and the placebo group (98.1% and 97.6%, respectively); serious adverse events were reported in 54.6% and 64.9% of the patients.

CONCLUSIONS

In patients with transthyretin amyloid cardiomyopathy, the receipt of acoramidis resulted in a significantly better four-step primary hierarchical outcome containing components of mortality, morbidity, and function than placebo. Adverse events were similar in the two groups. (Funded by BridgeBio Pharma; ATTRibute-CM ClinicalTrials.gov number, NCT03860935.).

Multicenter study of universal prophylaxis versus pre-emptive therapy for patients at intermediate risk (R+) for CMV following heart transplantation

INTRODUCTION

Heart transplant (HT) recipients with prior exposure to cytomegalovirus (CMV R+) are considered intermediate risk for CMV-related complications. Consensus guidelines allow for either universal prophylaxis (UP) or preemptive therapy (PET) (serial CMV testing) approaches to CMV prevention in such patients. Whether an optimal approach to mitigate CMV related risks exists in this setting remains uncertain. We therefore assessed the utility of PET as compared to UP in CMV R+ HT recipients.

METHODS

Retrospective analysis of all CMV R+ HT recipients from 6 U.S. centers between 2010 and 2018 was performed. The primary outcome was the development of CMV DNAemia or end-organ disease resulting in the initiation/escalation of anti-CMV therapy. The secondary outcome was CMV-related hospitalization. Additional outcomes included incidence of acute cellular rejection (ACR) ≥ grade 2R, death, cardiac allograft vasculopathy (CAV), and leukopenia.

RESULTS

Of 563 CMV R+ HT recipients, 344 (61.1%) received UP. PET was associated with increased risk for the primary (adjusted HR 3.95, 95% CI: 2.65-5.88, p < .001) and secondary (adjusted HR 3.19, 95% CI: 1.47-6.94, p = .004) outcomes, and with increased ACR ≥ grade 2R (PET 59.4% vs. UP 34.4%, p < .001). Incidence of detectable CAV was similar at 1 year (PET 8.2% vs. UP 9.5%, p = .698). UP was associated with increased incidence of leukopenia within 6 months post-HT (PET 34.7% vs. UP 43.6%, p = .036).

CONCLUSION

The use of a PET CMV prophylaxis strategy in intermediate risk HT recipients associated with increased risk of CMV infection and CMV-related hospitalization, and may associate with worse post-HT graft outcomes.

A bridge-to-bridge approach to heart transplantation using extracorporeal membrane oxygenation and total artificial heart

BACKGROUND

This study aims to describe the outcomes after heart transplantation using a bridge-to-bridge strategy with a sequence of extracorporeal membrane oxygenation (ECMO) support followed by temporary total artificial heart implantation (TAH-t).

METHODS

A retrospective, multicenter analysis of 54 patients who underwent TAH-t implantation following an ECMO for cardiogenic shock was performed (ECMO-TAH-t group). A control group of 163 patients who underwent TAH-t implantation as a direct bridge to transplantation (TAH-t group) was used to assess this strategy's impact on outcomes.

RESULTS

Fifty-four patients, averaging 47 ± 13 year old, underwent implantation of a TAH-t after 5.3 ± 3.4 days of ECMO perfusion for cardiogenic shock. In the ECMO-TAH-t group, 20 patients (20/54%; 37%) died after TAH-t implantation and 57 patients (57/163%; 35%) died in the TAH-t group (Gray test; P = .49). The top 3 causes of death of patients on TAH-t support were multisystem organ failure (40%), sepsis (20%), and neurologic events (20%). Overall, 32 patients (32/54%; 59%) underwent heart transplantation in the ECMO-TAH-t group compared with 106 patients (106/163%, 65%) in the TAH-t group (P = .44). No significant difference in survival was observed at 6 months, 1 year, and 3 years after heart transplant (ECMO-TAH-t group: 94%, 87%, and 80% vs 87%, 83%, and 76% in the TAH-t group, respectively). Deterioration of liver function (bilirubin, aspartate transaminase, and alanine aminotransferase levels on TAH-t) was associated with increased mortality before heart transplant in both groups.

CONCLUSIONS

Sequential bridging from ECMO to TAH-t followed by heart transplantation is a viable option for a group of highly selected patients.

Circulating microRNAs in cellular and antibody-mediated heart transplant rejection

BACKGROUND

Noninvasive monitoring of heart allograft health is important to improve clinical outcomes. MicroRNAs (miRs) are promising biomarkers of cardiovascular disease and limited studies suggest they can be used to noninvasively diagnose acute heart transplant rejection.

METHODS

The Genomic Research Alliance for Transplantation (GRAfT) is a multicenter prospective cohort study that phenotyped heart transplant patients from 5 mid-Atlantic centers. Patients who had no history of rejection after transplant were compared to patients with acute cellular rejection (ACR) or antibody-mediated rejection (AMR). Small RNA sequencing was performed on plasma samples collected at the time of an endomyocardial biopsy. Differential miR expression was performed with adjustment for clinical covariates. Regression was used to develop miR panels with high diagnostic accuracy for ACR and AMR. These panels were then validated in independent samples from GRAfT and Stanford University. Receiver operating characteristic curves were generated and area under the curve (AUC) statistics calculated. Distinct ACR and AMR clinical scores were developed to translate miR expression data for clinical use.

RESULTS

The GRAfT cohort had a median age of 52 years, with 35% females and 45% Black patients. Between GRAfT and Stanford, we included 157 heart transplant patients: 108 controls and 49 with rejection (50 ACR and 38 AMR episodes). After differential miR expression and regression analysis, we identified 12 miRs that accurately discriminate ACR and 17 miRs in AMR. Independent validation of the miR panels within GRAfT led to an ACR AUC 0.92 (95% confidence interval [CI]: 0.86-0.98) and AMR AUC 0.82 (95% CI: 0.74-0.90). The externally validated ACR AUC was 0.72 (95% CI: 0.59-0.82). We developed distinct ACR and AMR miR clinical scores (range 0-100), a score ≥ 65, identified ACR with 86% sensitivity, 76% specificity, and 98% negative predictive value, for AMR score performance was 82%, 84% and 97%, respectively.

CONCLUSIONS

We identified novel miRs that had excellent performance to noninvasively diagnose acute rejection after heart transplantation. Once rigorously validated, the unique clinical ACR and AMR scores usher in an era whereby genomic biomarkers can be used to screen and diagnose the subtype of rejection. These novel biomarkers may potentially alleviate the need for an endomyocardial biopsy while facilitating the initiation of targeted therapy based on the noninvasive diagnosis of ACR or AMR.

Percutaneous approach to left ventricular assist device decommissioning

OBJECTIVE

To assess the outcomes of a single-center experience with percutaneous left ventricular assist device (LVAD) decommissioning.

BACKGROUND

Patients with LVADs may eventually require their removal, either due to recovery of left ventricular function or recurrent complications. Traditionally, withdrawal of LVAD support has been managed with surgical device explantation, which carries significant procedural risks. Transcatheter LVAD decommissioning, with outflow graft occlusion and driveline transection, has recently been described as an alternative to surgical removal.

METHODS

Here, we report on a retrospective cohort of five consecutive cases treated with transcatheter LVAD decommissioning.

RESULTS

The procedure was effective in all cases, and no patient experienced procedure-related complications. At midterm follow-up, the three patients who had myocardial function recovery were alive and had not experienced heart failure-related symptoms or complications.

CONCLUSION

Percutaneous LVAD decommissioning appears to be a safe and effective approach to LVAD treatment discontinuation.

Caregiver Health-Related Quality of Life, Burden, and Patient Outcomes in Ambulatory Advanced Heart Failure: A Report From REVIVAL

Background Heart failure (HF) imposes significant burden on patients and caregivers. Longitudinal data on caregiver health-related quality of life (HRQOL) and burden in ambulatory advanced HF are limited. Methods and Results Ambulatory patients with advanced HF (n=400) and their participating caregivers (n=95) enrolled in REVIVAL (Registry Evaluation of Vital Information for VADs [Ventricular Assist Devices] in Ambulatory Life) were followed up for 24 months, or until patient death, left ventricular assist device implantation, heart transplantation, or loss to follow-up. Caregiver HRQOL (EuroQol Visual Analog Scale) and burden (Oberst Caregiving Burden Scale) did not change significantly from baseline to follow-up. At time of caregiver enrollment, better patient HRQOL by Kansas City Cardiomyopathy Questionnaire was associated with better caregiver HRQOL (P=0.007) and less burden by both time spent (P<0.0001) and difficulty (P=0.0007) of caregiving tasks. On longitudinal analyses adjusted for baseline values, better patient HRQOL (P=0.034) and being a married caregiver (P=0.016) were independently associated with better caregiver HRQOL. Patients with participating caregivers (versus without) were more likely to prefer left ventricular assist device therapy over time (odds ratio, 1.43; 95% CI, 1.03-1.99; P=0.034). Among patients with participating caregivers, those with nonmarried (versus married) caregivers were at higher composite risk of HF hospitalization, death, heart transplantation or left ventricular assist device implantation (hazard ratio, 2.99; 95% CI, 1.29-6.96; P=0.011). Conclusions Patient and caregiver characteristics may impact their HRQOL and other health outcomes over time. Understanding the patient-caregiver relationship may better inform medical decision making and outcomes in ambulatory advanced HF.

Combined Heart-Liver and Domino Liver Transplantation in Familial Amyloidosis

BACKGROUND

Combined heart-liver transplantation (CHLT) is the only curative option for patients with concomitant pathology affecting the heart and liver. In some cases, the native livers of familial amyloidosis (FA) patients may be suitable for domino transplantation into other recipients.

METHODS

Retrospective analysis (2013 to 2019) of all CHLT at our center was performed. Continuous data were presented as mean with standard deviation and discrete variables as percentages.

RESULTS

Familial amyloidosis was the indication for CHLT in 5 out of 6 patients. The mean recipient age was 55 ± 5.62 years. Two patients were bridged with total artificial heart. The mean model for end-stage liver disease score at transplant was 17.17 ± 3.7. Two explanted livers were used for transplantation in a domino fashion. The median intensive care and hospital stays were 5.5 and 19 days, respectively. Complications included renal failure (1), groin abscess (1), pulmonary embolism (1), and cardiac rejection (1). Patient and graft survival for both organs was 100% at a median follow-up of 59 (range 20-76) months.

DISCUSSION

Combined heart-liver transplantation for FA achieves excellent outcomes. The possible use of livers explanted from patients with FA for domino liver transplantation can contribute to the liver donor pool.

An interventional approach to left ventricular assist device outflow graft obstruction

BACKGROUND

LVADs provide life-sustaining treatment for patients with heart failure, but their complexity allows for complications. One complication, LVAD outflow graft obstruction, may be misdiagnosed as intraluminal thrombus, when more often it is extraluminal compression from biodebris accumulation. It can often be treated endovascularly with stenting. This case series describes diagnostic and procedural techniques for the treatment of left ventricular assist device (LVAD) outflow graft obstruction.

METHODS

We present four patients with LVADs who developed LVAD outflow graft obstruction within the bend relief-covered segment. All were initially diagnosed with computed tomographic angiography (CTA). All underwent invasive evaluation with intravascular ultrasound (IVUS), then were treated with stenting. After misdiagnosing a twist, we developed the technique of balloon "graftoplasty" to ensure suitability for stent delivery in subsequent cases.

RESULTS

All patients presented with low-flow alarms and symptoms of low output, and were diagnosed with outflow graft obstruction by CTA. In all four, IVUS confirmed an extraluminal etiology. Patient 1 was treated with stenting and had a good outcome. Patient 2's obstruction was from twisting, rather than biodebris accumulation, and had sub-optimal stent expansion and ultimately required surgery. Balloon "graftoplasty" was used in subsequent cases to ensure subsequent stent expansion. Patients 3 and 4 were successfully stented. All improved after treatment.

CONCLUSIONS

In patients with LVAD outflow graft obstruction, IVUS can distinguish intraluminal thrombus from extraluminal compression. Balloon "graftoplasty" can ensure that the outflow graft will respond to stenting. Many cases of LVAD outflow graft obstruction should be amenable to endovascular treatment.

Predictive Value of Cardiopulmonary Exercise Testing Parameters in Ambulatory Advanced Heart Failure

OBJECTIVES

This study sought to determine cardiopulmonary exercise (CPX) predictors of the combined outcome of durable mechanical circulatory support (MCS), transplantation, or death at 1 year among patients with ambulatory advanced heart failure (HF).

BACKGROUND

Optimal CPX predictors of outcomes in contemporary ambulatory advanced HF patients are unclear.

METHODS

REVIVAL (Registry Evaluation of Vital Information for ventricular assist devices [VADs] in Ambulatory Life) enrolled 400 systolic HF patients, INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) profiles 4-7. CPX was performed by 273 subjects 2 ± 1 months after study enrollment. Discriminative power of maximal (peak oxygen consumption [peak VO₂]; VO₂ pulse, circulatory power [CP]; peak systolic blood pressure • peak VO₂], peak end-tidal pressure CO₂ [PEtCO₂], and peak Borg scale score) and submaximal CPX parameters (ventilatory efficiency [VE/VCO₂ slope]; VO₂ at anaerobic threshold [VO₂AT]; and oxygen uptake efficiency slope [OUES]) to predict the composite outcome were assessed by univariate and multivariate Cox regression and Harrell's concordance statistic.

RESULTS

At 1 year, there were 39 events (6 transplants, 15 deaths, 18 MCS implantations). Peak VO₂, VO₂AT, OUES, peak PEtCO₂, and CP were higher in the no-event group (all p < 0.001), whereas VE/VCO₂ slope was lower (p < 0.0001); respiratory exchange ratio was not different. CP (hazard ratio [HR]: 0.89; p = 0.001), VE/VCO₂ slope (HR: 1.05; p = 0.001), and peak Borg scale score (HR: 1.20; p = 0.005) were significant predictors on multivariate analysis (model C-statistic: 0.80).

CONCLUSIONS

Among patients with ambulatory advanced HF, the strongest maximal and submaximal CPX predictor of MCS implantation, transplantation, or death at 1 year were CP and VE/VCO_2, respectively. The patient-reported measure of exercise effort (Borg scale score) contributed substantially to the prediction of outcomes, a surprising and novel finding that warrants further investigation. (Registry Evaluation of Vital Information for VADs in Ambulatory Life [REVIVAL]; NCT01369407).

HFSA/SAEM/ISHLT clinical expert consensus document on the emergency management of patients with ventricular assist devices

Mechanical circulatory support is now widely accepted as a viable long-term treatment option for patients with end-stage heart failure (HF). As the range of indications for the implantation of ventricular assist devices grows, so does the number of patients living in the community with durable support. Because of their underlying disease and comorbidities, in addition to the presence of mechanical support, these patients are at a high risk for medical urgencies and emergencies (Table 1). Thus, it is the responsibility of clinicians to understand the basics of their emergency care. This consensus document represents a collaborative effort by the Heart Failure Society of America, the Society for Academic Emergency Medicine, and the International Society for Heart and Lung Transplantation (ISHLT) to educate practicing clinicians about the emergency management of patients with ventricular assist devices. The target audience includes HF specialists and emergency medicine physicians, as well as general cardiologists and community-based providers.

The effects of canagliflozin compared to sitagliptin on cardiorespiratory fitness in type 2 diabetes mellitus and heart failure with reduced ejection fraction: The CANA-HF study

BACKGROUND

Canagliflozin reduces hospitalizations for heart failure (HF) in type 2 diabetes mellitus (T2DM). Its effect on cardiorespiratory fitness and cardiac function in patients with established HF with reduced ejection fraction (HFrEF) is unknown.

METHODS

We conducted a double-blind randomized controlled trial of canagliflozin 100 mg or sitagliptin 100 mg daily for 12 weeks in 88 patients, and measured peak oxygen consumption (VO₂ ) and minute ventilation/carbon dioxide production (VE/VCO₂ ) slope (co-primary endpoints for repeated measure ANOVA time_x_group interaction), lean peak VO₂ , ventilatory anaerobic threshold (VAT), cardiac function and quality of life (ie, Minnesota Living with Heart Failure Questionnaire [MLHFQ]), at baseline and 12-week follow-up.

RESULTS

The study was terminated early due to the new guidelines recommending canagliflozin over sitagliptin in HF: 17 patients were assigned to canagliflozin and 19 to sitagliptin, total of 36 patients. There were no significant changes in peak VO₂ and VE/VCO₂ slope between the two groups (P = .083 and P = .98, respectively). Canagliflozin improved lean peak VO₂ (+2.4 mL kg_LM^-1 min^-1 , P = .036), VAT (+1.5 mL kg^-1 min^-1 , P = .012) and VO₂ matched for respiratory exchange ratio (+2.4 mL Kg^-1 min^-1 , P = .002) compared to sitagliptin. Canagliflozin also reduced MLHFQ score (-12.1, P = .018).

CONCLUSIONS

In this small and short-term study of patients with T2DM and HFrEF, interrupted early after only 36 patients, canagliflozin did not improve the primary endpoints of peak VO₂ or VE/VCO₂ slope compared to sitagliptin, while showing favourable trends observed on several additional surrogate endpoints such as lean peak VO₂ , VAT and quality of life.

An Emergency Medicine-focused Summary of the HFSA/SAEM/ISHLT Clinical Consensus Document on the Emergency Management of Patients With Ventricular Assist Devices

Mechanical circulatory support is increasingly used as a long-term treatment option for patients with end-stage heart failure. Patients with implanted ventricular assist devices are at high risk for a range of diverse medical urgencies and emergencies. Given the increasing prevalence of mechanical circulatory support devices, this expert clinical consensus document seeks to help inform emergency medicine and prehospital providers regarding the approach to acute medical and surgical conditions encountered in these complex patients.

Elevated AT1R Antibody and Morbidity in Patients Bridged to Heart Transplant Using Continuous Flow Left Ventricular Assist Devices

BACKGROUND

We studied longitudinal levels of angiotensin-II type 1 receptor antibody (AT1R-Ab) and their effects on adverse events (death, treated rejection and cardiac allograft vasculopathy) in patients who were bridged to heart transplant using a continuous flow left ventricular assist device (LVAD).

METHODS AND RESULTS

Sera of 77 patients bridged to heart transplant (from 2009 to 2017) were tested for AT1R-Ab and CRP before and after LVAD. Elevated AT1R-Ab was defined as >10.0 U/mL. The median follow-up after transplant was 3.6 years (interquartile range, 2.2-5.6 years). After LVAD, AT1R-Ab levels increased from baseline and remained elevated until transplant. Freedom from adverse events at 5 years was lower in those with elevated AT1R-Ab levels at time of transplant. In an adjusted, multivariable Cox analysis, an AT1R-Ab level of >10 U/mL was associated with developing the primary end point (adjusted hazard ratio 3.4, 95% confidence interval 1.2-9.2, P = .017). Although C-reactive protein levels were high before and after LVAD placement, C-reactive protein did not correlate with AT1R-Ab.

CONCLUSIONS

In LVAD patients bridged to heart transplant, an increased AT1R-Ab level at time of transplant was associated with poor outcomes after heart transplant. Post-LVAD AT1R-Ab elevations were not correlated with serum markers of systemic inflammation. Larger studies are needed to examine the pathologic role of AT1R-Ab in heart transplant.

Determinants of Cardiorespiratory Fitness in Patients with Heart Failure Across a Wide Range of Ejection Fractions

Impaired cardiorespiratory fitness (CRF) in heart failure (HF) is influenced by a complex array of cardiac and extracardiac factors. The study aimed to identify clinical determinants of CRF measured as peak oxygen consumption (peak VO₂) in HF patients, and to determine a peak VO₂ prediction model using regression equations. Retrospective analysis of 200 HF patients who completed treadmill cardiopulmonary exercise testing and underwent Doppler echocardiography and/or biomarker analysis on the same day was performed. After univariate linear regression analysis, a multivariate peak VO₂ prediction model was developed using significant variables in a stepwise linear regression analysis. In subjects with repeated testing, Pearson's correlation was used to assess correlations between measured and predicted change in peak VO₂ (Δpeak VO₂) over time. Mean age was 57 years, with 55% being male. Stepwise linear regression was used to generate a weighted model for peak VO₂: 30.895 + (-0.112•age[years]) + (0.296•hemoglobin [g/dl]) + (-0.101•E/e'[unit change]) + (-0.202• body mass index [kg/m²]) + (-0.593• N-terminal pro-brain natriuretic peptide [log_N pg/ml])) + (-1.349•CRP [log mg/L]). Predicted peak VO₂ correlated strongly with measured peak VO₂ in HF with reduced ejection fraction and HF with preserved ejection fraction patients (r = +0.63, p <0.001; r = +0.64, p <0.001, respectively). Predicted Δpeak VO₂ correlated with measured Δpeak VO₂ (r = +0.23, p <0.001). In conclusion, in patients with HF across a wide range of left ventricular ejection fraction, age, systemic inflammation, oxygen carrying capacity, obesity, and elevated filling pressures are the strongest predictors of impaired CRF. The proposed CRF model allows prediction of peak VO₂ in HF patients and may be used to estimate peak VO₂ changes over time.

Impact of Socioeconomic Factors on Patient Desire for Early LVAD Therapy Prior to Inotrope Dependence

BACKGROUND

Worsening heart failure (HF) and health-related quality of life (HRQOL) have been shown to impact the decision to proceed with left ventricular assist device (LVAD) implantation, but little is known about how socioeconomic factors influence expressed patient preference for LVAD.

METHODS AND RESULTS

Ambulatory patients with advanced systolic HF (n=353) reviewed written information about LVAD therapy and completed a brief survey to indicate whether they would want an LVAD to treat their current level of HF. Ordinal logistic regression analyses identified clinical and demographic predictors of LVAD preference. Higher New York Heart Association (NYHA) class, worse HRQOL measured by Kansas City Cardiomyopathy Questionnaire, lower education level, and lower income were significant univariable predictors of patients wanting an LVAD. In the multivariable model, higher NYHA class (OR [odds ratio]: 1.43, CI [confidence interval]: 1.08-1.90, P = .013) and lower income level (OR: 2.10, CI: 1.18 - 3.76, P = .012 for <$40,000 vs >$80,000) remained significantly associated with wanting an LVAD.

CONCLUSION

Among ambulatory patients with advanced systolic HF, treatment preference for LVAD was influenced by level of income independent of HF severity. Understanding the impact of socioeconomic factors on willingness to consider LVAD therapy may help tailor counseling towards individual needs.

5947Predictive role of C-reactive protein levels in patients with ST-segment elevation acute myocardial infarction for heart failure related events

Background

ST-segment elevation myocardial infarction (STEMI) is associated with an intense acute inflammatory response and an increased risk of death and heart failure (HF). C-reactive protein (CRP) is the inflammatory biomarker most commonly used for risk stratification in patients with cardiovascular diseases. CRP levels are known to rise and fall during STEMI in response to myocardial injury. In this study, we analyzed whether admission CRP or delayed CRP (measured at 72 hours after admission) held a greater predictive value for adverse HF events in patients with STEMI.

Methods

We analyzed data from the VCUART3 clinical trial enrolling 99 patients with STEMI within 12 hours of presentation at 3 sites in the United States of America treated with anakinra or placebo. CRP levels were measured with a high-sensitivity assay at time of admission and again at 72 hours later. A dedicated committee composed of individuals not involved in the conduct of the trial adjudicated HF events including a composite endpoint of death from any reason or incidence of HF defined as new-onset HF requiring hospital admission or a new prescription for a loop diuretic (D+HF) and a composite endpoint of death and HF hospitalization (D+HHF) at 1 year. We used a time-dependent Cox-regression analysis to determine the association of CRP at admission or at 72 hours with the outcomes of interest in univariate and multivariate analysis. Data are presented as median and interquartile range. (ClinicalTrials NCT01950299)

Results

CRP levels from admission and 72 hours were available in 90 and 87 subjects respectively and they increased from 4.6 [2.8–8.5] mg/L to 11.6 [4.6–24.5] mg/L (P<0.001). Both admission CRP (CRP0) and CRP at 72 hours (CRP72) were associated with the risk of D+HF (P=0.011 and <0.001, respectively) and of D+HHF (P=0.010 and P<0.001, respectively); however at multivariate analysis, only CRP72 remained significantly associated with the risk of D+HF (P=0.001) and D+HHF (P=0.004) while CRP0 was not. CRP72 significantly correlated with NTproBNP levels at 72 hours (NTproBNP72, Spearman rho R=+0.37, P=0.001). NTproBNP72 predicted D+HF (P=0.030) but not independently of CRP72 (P=0.096 for NTproBNP72 and P=0.007 for CRP72 at multivariate analysis including the 2 variables). NTproBNP72 did not predict D-HHF.

Conclusions

Among contemporary patients with STEMI, the levels of CRP at 72 hours after admission was superior to admission CRP levels for predicting the incidence of HF events, and independent of NTproBNP levels. Our results indicate the importance of the inflammatory response during STEMI, supporting the concept of inhibiting the inflammatory response as a therapeutic strategy.

Acknowledgement/Funding

Funded by NHLBI 1R34HL121402; Drug supply from Swedish Orphan Biovitrum

Left Ventricular Assist Device Outflow Graft Compression: Incidence, Clinical Associations and Potential Etiologies

BACKGROUND

Left ventricular assist devices (LVADs) have revolutionized the treatment of advanced heart failure, but proliferation of device therapy has unmasked potential complications. Reports have emerged of outflow graft narrowing due to extrinsic compression.

METHODS AND RESULTS

The records of patients with LVADs that had been implanted at our institution were reviewed. Those who had postimplantation computed tomography angiographies sufficient to analyze the outflow graft lumen were identified, and the studies were analyzed to characterize the outflow graft lumen. We identified 241 patients; 110 (46%) had suitable computed tomography angiographies. Of those, 15 (14%) had evidence of outflow graft lumen narrowing, all in HeartMate devices and all within the portion covered by the bend relief. Of the 15, 3 underwent invasive examination, all without intraluminal thrombus but, rather, with biodebris between the bend relief and the outflow graft. Patients with HeartWare devices had a wide range of biodebris accumulation surrounding the outflow graft but no cases of lumen narrowing. On multivariable analysis, 1) time from device implant to scan, 2) nonischemic cardiomyopathy and 3) age at implant were significantly associated with higher risk of graft narrowing.

CONCLUSION

Outflow graft narrowing can be seen in a number of patients with HeartMate LVADs within the portion covered by the bend relief. In the limited number of patients who underwent invasive evaluation, the narrowing was found to arise from extrinsic compression rather than intraluminal thrombus. The clinical significance of this requires further investigation.

Educating Resident and Fellow Physicians on the Ethics of Mechanical Circulatory Support

Mechanical circulatory support (MCS) such as extracorporeal membrane oxygenation, left ventricular assist devices and total artificial hearts have altered the natural history of heart failure, and specialists in the fields of cardiology and cardiothoracic surgery are faced with more complex ethical considerations than ever before. Residency and fellowship training programs, however, do not have formal curricula in medical ethics as it applies to MCS. In response, this article proposes that ethics be integrated into graduate medical education with a focus on the following 6 constructs: patient best interest, respect for autonomy, informed consent, shared decision making, surrogate decision making, and end-of-life care. Curricula should offer learning experiences that help physicians navigate common ethical challenges encountered in practice.

Usefulness of Estimated Plasma Volume at Postdischarge Follow-Up to Predict Recurrent Events in Patients With Heart Failure

Hospital readmission for patients admitted with heart failure is a persistent problem. Better identification of patients at high risk of readmission for volume overload could have clinical implications. We evaluated estimated plasma volume (ePV), a marker of congestion, to predict readmission for patients seen early after discharge for heart failure. We identified patients hospitalized with a primary heart failure diagnosis and were then seen in a postdischarge clinic. We assessed clinical factors, ePV (derived from hemoglobin and hematocrit), and B-type natriuretic peptide (BNP). The primary outcome was death or readmission for heart failure within 90 days of discharge. We identified 218 patients, of whom 23% experienced the primary outcome. No clinical variables at time of admission were different between those who did and did not experience the primary outcome, nor were BNP (1,581 vs 1,267 pg/ml, p = 0.33) or ePV (6.00 vs 5.80, p = 0.36). At clinic follow-up, both BNP (1,164 vs 636, p = 0.002) and ePV (6.18 vs 5.58, p = 0.02) were higher in those with subsequent events. Kaplan-Meier survival analysis showed that the lowest tertile of ePV had significantly lower incidence of the primary outcome than the other 2 tertiles (12% vs 29% and 27%, p = 0.02). Estimated plasma volume remained independently predictive of outcomes after controlling for BNP (p <0.05). In conclusion, EPV may be predictive of death or hospital readmission in heart failure patients seen soon after discharge, independent of BNP. Its potential warrants future prospective research evaluating its utility in larger heart failure cohorts.

Transthyretin Cardiac Amyloidosis

PURPOSE OF REVIEW

Transthyretin (TTR)-related cardiac amyloidosis is a progressive infiltrative cardiomyopathy that mimics hypertensive, hypertrophic heart disease and may go undiagnosed. Transthyretin-derived amyloidosis accounts for 18% of all cases of cardiac amyloidosis. Thus, the study's purpose is to provide a comprehensive review of transthyretin cardiac amyloidosis.

RECENT FINDINGS

Wild-type transthyretin (ATTRwt) protein causes cardiac amyloidosis sporadically, with 25 to 36% of the population older than 80 years of age are at risk to develop a slowly progressive, infiltrative amyloid cardiomyopathy secondary to ATTRwt. In contrast, hereditary amyloidosis (ATTRm) is an autosomal dominant inherited disease associated with more than 100 point mutations in the transthyretin gene and has a tendency to affect the heart and nervous system. Up to 4% of African-Americans carry the Val122Ile mutation in the transthyretin gene, the most prevalent cause of hereditary cardiac amyloidosis in the USA. Identifying transthyretin cardiac amyloidosis requires increased awareness of the prevalence, signs and symptoms, and diagnostic tools available for discrimination of this progressive form of cardiomyopathy associated with left ventricular hypertrophy. While there are no FDA-approved medical treatments, investigation is underway on agents to reduce circulating mutated transthyretin.

Accuracy of Seattle Heart Failure Model and HeartMate II Risk Score in Non-Inotrope-Dependent Advanced Heart Failure Patients: Insights From the ROADMAP Study (Risk Assessment and Comparative Effectiveness of Left Ventricular Assist Device and Medical Management in Ambulatory Heart Failure Patients)

BACKGROUND

Timing of left ventricular assist device (LVAD) implantation in advanced heart failure patients not on inotropes is unclear. Relevant prediction models exist (SHFM [Seattle Heart Failure Model] and HMRS [HeartMate II Risk Score]), but use in this group is not established.

METHODS AND RESULTS

ROADMAP (Risk Assessment and Comparative Effectiveness of Left Ventricular Assist Device and Medical Management in Ambulatory Heart Failure Patients) is a prospective, multicenter, nonrandomized study of 200 advanced heart failure patients not on inotropes who met indications for LVAD implantation, comparing the effectiveness of HeartMate II support versus optimal medical management. We compared SHFM-predicted versus observed survival (overall survival and LVAD-free survival) in the optimal medical management arm (n=103) and HMRS-predicted versus observed survival in all LVAD patients (n=111) using Cox modeling, receiver-operator characteristic (ROC) curves, and calibration plots. In the optimal medical management cohort, the SHFM was a significant predictor of survival (hazard ratio=2.98; P<0.001; ROC area under the curve=0.71; P<0.001) but not LVAD-free survival (hazard ratio=1.41; P=0.097; ROC area under the curve=0.56; P=0.314). SHFM showed adequate calibration for survival but overestimated LVAD-free survival. In the LVAD cohort, the HMRS had marginal discrimination at 3 (Cox P=0.23; ROC area under the curve=0.71; P=0.026) and 12 months (Cox P=0.036; ROC area under the curve=0.62; P=0.122), but calibration was poor, underestimating survival across time and risk subgroups.

CONCLUSIONS

In non-inotrope-dependent advanced heart failure patients receiving optimal medical management, the SHFM was predictive of overall survival but underestimated the risk of clinical worsening and LVAD implantation. Among LVAD patients, the HMRS had marginal discrimination and underestimated survival post-LVAD implantation.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01452802.

A Phase 2a dose-escalation study of the safety, tolerability, pharmacokinetics and haemodynamic effects of BMS-986231 in hospitalized patients with heart failure with reduced ejection fraction

Aims

This study was designed to evaluate the safety, tolerability and haemodynamic effects of BMS‐986231, a novel second‐generation nitroxyl donor with potential inotropic, lusitropic and vasodilatory effects in patients hospitalized with decompensated heart failure and reduced ejection fraction (HFrEF).

Methods and results

Forty‐six patients hospitalized with decompensated HFrEF were enrolled into four sequential dose‐escalation cohorts in this double‐blind, randomized, placebo‐controlled Phase 2a study. Patients with baseline pulmonary capillary wedge pressure (PCWP) of ≥20 mmHg and a cardiac index of ≤2.5 L/min/m² received one 6‐h i.v. infusion of BMS‐986231 (at 3, 5, 7 or 12 µg/kg/min) or placebo. BMS‐986231 produced rapid and sustained reductions in PCWP, as well as consistent reductions in time‐averaged pulmonary arterial systolic pressure, pulmonary arterial diastolic pressure and right atrial pressure. BMS‐986231 increased non‐invasively measured time‐averaged stroke volume index, cardiac index and cardiac power index values, and decreased total peripheral vascular resistance. There was no evidence of increased heart rate, drug‐related arrhythmia or symptomatic hypotension with BMS‐986231. Analyses of adverse events throughout the 30‐day follow‐up did not identify any toxicities specific to BMS‐986231, with the potential exception of infrequent mild‐to‐moderate headaches during infusion. There were no treatment‐related serious adverse events.

Conclusions

BMS‐986231 demonstrated a favourable safety and haemodynamic profile in patients hospitalized with advanced heart failure. Based on preclinical data and these study's findings, it is possible that the haemodynamic benefits may be mediated by inotropic and/or lusitropic as well as vasodilatory effects. The therapeutic potential of BMS‐986231 should be further assessed in patients with heart failure.

Transthyretin Cardiac Amyloidosis in Black Americans

Transthyretin-related cardiac amyloidosis is a progressive infiltrative cardiomyopathy that mimics hypertensive and hypertrophic heart disease and often goes undiagnosed. In the United States, the hereditary form disproportionately afflicts black Americans, who when compared with whites with wild-type transthyretin amyloidosis, a phenotypically similar condition, present with more advanced disease despite having a noninvasive method for early identification (genetic testing). Although reasons for this are unclear, this begs to consider the inadequate access to care, societal factors, or a biological basis. In an effort to improve awareness and explore unique characteristics, we review the pathophysiology, epidemiology, and therapeutic strategies for transthyretin amyloidosis and highlight diagnostic pitfalls and clinical pearls for identifying patients with amyloid heart disease.

Patient-Reported Health-Related Quality of Life Is a Predictor of Outcomes in Ambulatory Heart Failure Patients Treated With Left Ventricular Assist Device Compared With Medical Management

Background—

The prospective observational ROADMAP study (Risk Assessment and Comparative Effectiveness of Left Ventricular Assist Device and Medical Management) demonstrated that ambulatory advanced heart failure patients selected for left ventricular assist device (LVAD) were more likely to be alive at 1 year on original therapy with ≥75-m improvement in 6-minute walk distance compared with patients assigned to optimal medical management. Whether baseline health-related quality of life (hrQoL) resulted in a heterogeneity of this treatment benefit is unknown.

Methods and Results—

Patient-reported hrQoL was assessed with EuroQol questionnaire and visual analogue scale (VAS). We aimed to identify predictors of event-free survival and survival with acceptable hrQoL (VAS≥60). LVAD patients had significant improvement in 3 of 5 EuroQol dimensions ( P <0.05), but no significant changes were observed with optimal medical management. Among patients with baseline VAS<55, survival on original treatment was lower for optimal medical management patients compared with those assigned to LVAD (58±7% versus 82±5%; P =0.004). No such difference was seen if baseline VAS was ≥55 (70±7% versus 75±9%; P =0.79). Survival on original therapy with acceptable quality of life was also more likely with LVAD versus optimal medical management if baseline VAS was <55, whereas outcomes in patients with higher baseline VAS scores were similar regardless of treatment assignment ( P =0.046 for treatment arm and baseline VAS interaction).

Conclusions—

LVAD therapy resulted in improvement of patient health status in heart failure patients with low self-reported hrQoL, but not in patients with acceptable quality of life at the time of LVAD implantation. Patient-reported hrQoL should be integrated into decision making concerning the use and timing of LVAD therapy in heart failure patients who are symptom limited but remain ambulatory.

Clinical Trial Registration—

URL: http://www.ClinicalTrials.gov . Unique identifier: NCT01452802.

Infections in Patients with a Total Artificial Heart Are Common but Rarely Fatal

Patients who received a total artificial heart (TAH) at Virginia Commonwealth University (VCU) between January 1, 2010 and December 31, 2011 were identified from the VCU Mechanical Circulatory Support Clinical Database. Retrospective data extraction from the medical records was performed from the time of TAH implantation until heart transplantation or death. Infections were classified as confirmed or suspected. Twenty-seven men and five women, mean age 49.5 years (range 24-68 years) received a TAH. The mean duration of TAH support was 225 days (range 1-1,334 days). Of the 32 patients, 4 (12.5%) died and 28 (87.5 %) underwent heart transplantation. Causes of death were pneumonia (n = 1), TAH malfunction (n = 1), refractory cardiogenic shock (n = 1), and respiratory failure (n = 1). Seventy documented and 13 suspected infections developed in 25 patients (78%). The most common sources of infection were urinary tract (n = 26), respiratory tract (n = 18), and bloodstream (n = 11). There were five pump infections and two driveline infections. The number of infections per patient ranged from 0 to 10. Sixteen different pathogens were identified; the most common were: Klebsiella pneumoniae (n = 15), coagulase-negative Staphylococci (n = 10), Enterococcus species (n = 9), and Enterobacter species (n = 8). Mortality directly attributable to infection was infrequent.

The total artificial heart

The total artificial heart (TAH) is a form of mechanical circulatory support in which the patient's native ventricles and valves are explanted and replaced by a pneumatically powered artificial heart. Currently, the TAH is approved for use in end-stage biventricular heart failure as a bridge to heart transplantation. However, with an increasing global burden of cardiovascular disease and congestive heart failure, the number of patients with end-stage heart failure awaiting heart transplantation now far exceeds the number of available hearts. As a result, the use of mechanical circulatory support, including the TAH and left ventricular assist device (LVAD), is growing exponentially. The LVAD is already widely used as destination therapy, and destination therapy for the TAH is under investigation. While most patients requiring mechanical circulatory support are effectively treated with LVADs, there is a subset of patients with concurrent right ventricular failure or major structural barriers to LVAD placement in whom TAH may be more appropriate. The history, indications, surgical implantation, post device management, outcomes, complications, and future direction of the TAH are discussed in this review.