Patients' and physicians' beliefs and attitudes towards integrating personalized risk estimates into patient education about left ventricular assist device therapy

BACKGROUND

Personalized risk (PR) estimates may enhance clinical decision making and risk communication by providing individualized estimates of patient outcomes. We explored stakeholder attitudes toward the utility, acceptability, usefulness and best-practices for integrating PR estimates into patient education and decision making about Left Ventricular Assist Device (LVAD).

METHODS AND RESULTS

As part of a 5-year multi-institutional AHRQ project, we conducted 40 interviews with stakeholders (physicians, nurse coordinators, patients, and caregivers), analyzed using Thematic Content Analysis. All stakeholder groups voiced positive views towards integrating PR in decision making. Patients, caregivers and coordinators emphasized that PR can help to better understand a patient's condition and risks, prepare mentally and logistically for likely outcomes, and meaningfully engage in decision making. Physicians felt it can improve their decision making by enhancing insight into outcomes, enhance tailored pre-emptive care, increase confidence in decisions, and reduce bias and subjectivity. All stakeholder groups also raised concerns about accuracy, representativeness and relevance of algorithms; predictive uncertainty; utility in relation to physician's expertise; potential negative reactions among patients; and overreliance.

CONCLUSION

Stakeholders are optimistic about integrating PR into clinical decision making, but acceptability depends on prospectively demonstrating accuracy, relevance and evidence that benefits of PR outweigh potential negative impacts on decision making quality.

Repeat left ventricular-assisted device exchange and upgrade from second- to third-generation devices in a high-volume single center

BACKGROUND

Pump exchange is an established strategy to treat LVAD-related complications such as thrombosis, infection, and driveline failure. Pump upgrades with an exchange to newer generation devices are being performed to the advantage of the patient on long-term support. The safety and efficacy of a repeat LVAD exchange with a concomitant upgrade to a third-generation pump have not been reported.

METHODS

We performed a retrospective analysis of all consecutive patients who underwent a repeat LVAD device exchange and upgrade to HeartMate III (HMIII) at Houston Methodist Hospital between December 2018 and December 2020.

RESULTS

Five patients underwent exchange and upgrade to HMIII within the specified timeframe. Four patients had already had two prior exchanges (all HMII to HMII), and one patient had one prior exchange (HVAD to HVAD). In all cases, implantation was performed as destination therapy. The surgical exchange was performed via redo median sternotomy on full cardiopulmonary bypass. No unplanned redo surgery of the device component was required. In-hospital mortality was 20% in this very high-risk population. At 1-, 3-, and 6-month follow-up, all discharged patients were on HMIII support, with no major LVAD-related adverse events reported.

CONCLUSION

We report the feasibility and safety of a repeat pump exchange with an upgrade to HMIII in a high-volume center. The decision for medical therapy versus surgical exchange has to be tailored to individual cases based on risk factors and clinical stability but in expert hands, even a re-redo surgical approach grants options for good medium-term outcomes.

Body Mass Index and Mortality in Cardiogenic Shock

We explored the association of body mass index (BMI) with mortality in cardiogenic shock (CS). Using the Cardiogenic Shock Working Group registry, we assessed the impact of BMI on mortality using restricted cubic splines in a multivariable logistic regression model adjusting for age, gender, and race. We also assessed mortality, device use, and complications in BMI categories, defined as underweight (<18.5 kg/m2), normal (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), obese (30-39.9 kg/m2), and severely obese (>40 kg/m2) using univariable logistic regression models. Our cohort had 3,492 patients with CS (mean age = 62.1 ± 14 years, 69% male), 58.0% HF-related CS (HF-CS), and 27.8% acute myocardial infarction (AMI) related CS. Body mass index was a significant predictor of mortality in multivariable regression using restricted cubic splines (p < 0.0001, p = 0.194 for nonlinearity). When stratified by categories, patients with healthy weight had lower mortality (29.0%) than obese (35.1%, p = 0.003) or severely obese (36.7%, p = 0.01). In HF-CS cohort, the healthy weight patients had the lowest mortality (21.7%), whereas it was higher in the underweight (37.5%, p = 0.012), obese (29.2%, p = 0.003), and severely obese (29.9%, p = 0.019). There was no difference in mortality among BMI categories in AMI-CS.

Bloodstream infections in prolonged use of axillary-placed, intra-aortic balloon-pump support: A single-center study

Infections from prolonged use of axillary intra-aortic balloon pumps (IABPs) have not been well studied. Bloodstream infection (BSI) occurred in 13% of our patients; however, no difference in outcome was noted between those with BSI and those without. Further studies regarding protocol developments that minimize BSI risk are needed.

Effectiveness of combined plasma cell therapy and costimulation blockade based desensitization regimen in heart transplant candidates

BACKGROUND

Desensitization is one of the strategies to reduce antibodies and facilitate heart transplantation in highly sensitized patients. We describe our center's desensitization experience with combination of plasma cell (PC) depletion therapy (with proteasome inhibitor or daratumumab) and costimulation blockade (with belatacept).

METHODS

We reviewed five highly sensitized patients who underwent desensitization therapy with plasma cell depletion and costimulation blockade. We evaluated the response to therapy by measuring the changes in cPRA, average MFI, and number of positive beads > 5000MFI.

RESULTS

Five patients, mean age of 56 (37-66) years with average cPRA of 98% at 5000 MFI underwent desensitization therapy. After desensitization, mean cPRA decreased from 98% to 70% (p = .09), average number of beads > 5000 MFI decreased from 59 to 37 (p = .15), and average MFI of beads > 5000 MFI decreased from 16713 to 13074 (p = .26).

CONCLUSION

Combined PC depletion and CoB could be a reasonable strategy for sustained reduction in antibodies in highly sensitized patients being listed for heart transplantation.

Procedural Insights and Clinical Outcomes of a Novel Superior Vena Cava Occlusion Device for Acute Heart Failure: A Single-Center Experience

The preCARDIA system is a device combining a balloon-mounted catheter and an extracorporeal system designed for intermittent occlusion of the superior vena cava. Studies have established safety and efficacy in acute decompensated heart failure. We present a single-center experience detailing 90 days outcomes and procedural insights. A 24 hours therapy session demonstrated reduced pulmonary wedge pressures and increased urine output, with cardiac output remaining unchanged. There was one readmission and no heart failure-related readmissions at 90 days. The preCARDIA device appears to be a safe mechanical diuretic strategy to manage patients with acute decompensated heart failure beyond current therapeutic strategies.

Impact of Female Sex on Cardiogenic Shock Outcomes: A Cardiogenic Shock Working Group Report

BACKGROUND

Studies reporting cardiogenic shock (CS) outcomes in women are scarce.

OBJECTIVES

The authors compared survival at discharge among women vs men with CS complicating acute myocardial infarction (AMI-CS) and heart failure (HF-CS).

METHODS

The authors analyzed 5,083 CS patients in the Cardiogenic Shock Working Group. Propensity score matching (PSM) was performed with the use of baseline characteristics. Logistic regression was performed for log odds of survival.

RESULTS

Among 5,083 patients, 1,522 were women (30%), whose mean age was 61.8 ± 15.8 years. There were 30% women and 29.1% men with AMI-CS (P = 0.03). More women presented with de novo HF-CS compared with men (26.2% vs 19.3%; P < 0.001). Before PSM, differences in baseline characteristics and sex-specific outcomes were seen in the HF-CS cohort, with worse survival at discharge (69.9% vs 74.4%; P = 0.009) and a higher rate of maximum Society for Cardiac Angiography and Interventions stage E (26% vs 21%; P = 0.04) in women than in men. Women were less likely to receive pulmonary artery catheterization (52.9% vs 54.6%; P < 0.001), heart transplantation (6.5% vs 10.3%; P < 0.001), or left ventricular assist device implantation (7.8% vs 10%; P = 0.01). Regardless of CS etiology, women had more vascular complications (8.8% vs 5.7%; P < 0.001), bleeding (7.1% vs 5.2%; P = 0.01), and limb ischemia (6.8% vs 4.5%; P = 0.001). More vascular complications persisted in women after PSM (10.4% women vs 7.4% men; P = 0.06).

CONCLUSIONS

Women with HF-CS had worse outcomes and more vascular complications than men with HF-CS. More studies are needed to identify barriers to advanced therapies, decrease complications, and improve outcomes of women with CS.

Translating Pressure Into Practice: Operational Characteristics of Ambulatory Hemodynamic Monitoring Program in the United States

BACKGROUND

Ambulatory hemodynamic monitoring (AHM) using an implantable pulmonary artery pressure sensor (CardioMEMS) is effective in improving outcomes for patients with heart failure. The operations of AHM programs are crucial to clinical efficacy of AHM yet have not been described.

METHODS AND RESULTS

An anonymous, voluntary, web-based survey was developed and emailed to clinicians at AHM centers in the United States. Survey questions were related to program volume, staffing, monitoring practices, and patient selection criteria. Fifty-four respondents (40%) completed the survey. Respondents were 44% (n = 24) advanced HF cardiologists and 30% (n = 16) advanced nurse practitioners. Most respondents practice at a center that implants left ventricular assist devices (70%) or performs heart transplantation (54%). Advanced practice providers provide day-to-day monitoring and management in most programs (78%), and use of protocol-driven care is limited (28%). Perceived patient nonadherence and inadequate insurance coverage are cited as the primary barriers to AHM.

CONCLUSIONS

Despite broad US Food and Drug Administration approval for patients with symptoms and at increased risk for worsening heart failure, the adoption of pulmonary artery pressure monitoring is concentrated at advanced heart failure centers, and modest numbers of patients are implanted at most centers. Understanding and addressing the barriers to referral of eligible patients and to broader adoption in community heart failure programs is needed to maximize the clinical benefits of AHM.

Imaging for implementation of heart failure guidelines

The classification of heart failure with implications for pharmacological therapeutic interventions rests on defining ejection fraction (EF) which is an imaging parameter. Imaging can provide diagnostic clues as to aetiology of heart failure; it can also guide and help assess response to treatment. Echocardiography, CMR, cardiac computed tomography, positron emission tomography, and Tc 99 m pyrophosphate scanning provide information about the aetiology of heart failure. Further, echocardiography plays the primary role in the evaluation of LV diastolic function and the estimation of left ventricular (LV) filling pressures both at rest and with exercise during diastolic stress testing. Heart failure guidelines recognize four stages (A, B, C, and D) for heart failure. Cardiac imaging along with risk factors and clinical status is needed for identifying these stages. There are joint societal echocardiographic guidelines by American Society of Echocardiography (ASE) of Echocardiography and European Association of Cardiovascular Imaging that are applicable to the imaging of heart failure patients. There are also separate guidelines for the evaluation of patients being considered for LV assist device implantation and for multimodality imaging of patients with heart failure and preserved EF. Cardiac catheterization is needed in patients whose haemodynamic status is uncertain after clinical and echocardiographic evaluation and to evaluate for coronary artery disease. Myocardial biopsy can identify the presence of myocarditis or specific infiltrative diseases when the findings by non-invasive imaging are not conclusive.

Cardiac Tamponade With a Transaortic Percutaneous Left Ventricular Assist Device: When Alarms Caused No Alarm

A 57-year-old man with end-stage heart failure presented with incessant ventricular tachycardia in the setting of cardiogenic shock, requiring support with a percutaneous left ventricular assist device. He underwent ablation of the ventricular tachycardia. Hours later the console alarm was evident, and the patient experienced worsening shock and elevated central venous pressure, leading to a diagnosis of cardiac tamponade. (Level of Difficulty: Advanced.).

Outflow cannula alignment in continuous flow left ventricular devices is associated with stroke

We sought to evaluate whether differences in left ventricular assist device (LVAD) canula alignment are associated with stroke. There is a paucity of clinical data on contribution of LVAD canulae alignment to strokes. We conducted a retrospective analysis of patients who underwent LVAD implantation at Houston Methodist hospital from 2011 to 2016 and included those who had undergone cardiac computed tomography (CT) with contrast. LVAD graft alignment using X-ray, echocardiography, and cardiac CT was evaluated. The primary outcome was stroke within 1 year of LVAD implantation. Of the 101 patients that underwent LVAD Implantation and cardiac CT scan during the study period, 78 met inclusion criteria. The primary outcome occurred in 12 (15.4%) patients with a median time to stroke of 77 days (interquartile range: 42-132 days). Of these, 10 patients had an ischemic and two had hemorrhagic strokes. The predominant device type was Heart Mate II (94.8%). Patients with LVAD outflow cannula to aortic angle lesser than 37.5° and those with outflow graft diameter of anastomosis less than 1.5 cm (assessed by cardiac CT) had significantly higher stroke risk (p < 0.001 and p = 0.01 respectively). In HMII patients, a lower LVAD speed at the time of CT scan was associated with stroke. Further studies are needed to identify optimal outflow graft configuration to mitigate stroke risk.

Impact of exercise on pulmonary artery pressure in patients with heart failure using an ambulatory pulmonary artery pressure monitor

Background

In this multicenter prospective study, we explored the relationship between pulmonary artery pressure (PAP) at rest and in response to a 6-min walk test (6MWT) in ambulatory patients with heart failure (HF) with an implantable PAP sensor (CardioMEMS, Abbott).

Methods

Between 5/2019 and 2/2021, HF patients with a CardioMEMS sensor were recruited from seven sites. PAP was recorded in the supine and seated position at rest and in the seated position immediately post-exercise.

Results

In our cohort of 66 patients, mean age was 70 ± 12 years, 67% male, left ventricular ejection fraction (LVEF) < 50% in 53%, mean 6MWT distance was 277 ± 95 meters. Resting seated PAPs were 31 ± 15 mmHg (systolic), 13 ± 8 mmHg (diastolic), and 20 ± 11 mmHg (mean). The pressures were lower in the seated rather than the supine position. After 6MWT, the pressures increased to PAP systolic 37 ± 19 mmHg (p < 0.0001), diastolic 15 ± 10 mmHg (p = 0.006), and mean 24 ± 13 mmHg (p < 0.0001). Patients with elevated PAP diastolic at rest (>15 mmHg) demonstrated a greater increase in post-exercise PAP.

Conclusion

The measurement of PAP with CardioMEMS is feasible immediately post-exercise. Despite being well-managed, patients had severely limited functional capacity. We observed a significant increase in PAP with ambulation which was greater in patients with higher baseline pressures.

2013. Bloodstream Infections in Advanced Heart Failure Patients Requiring Prolonged Use of Axillary Intra-Aortic Balloon Pumps - A Single Center Study

Background

Bloodstream infections (BSI) impact outcomes in critically ill patients. Institutions and quality and performance improvement efforts to minimize catheter associated infections are valued to optimize outcomes. While intra-aortic balloon pumps (IABP) implanted through the axillary route have been recently used in cardiogenic shock patients for prolonged support, the incidence and associated significance of BSI remains unknown in this cohort. The aim of this study was to assess the incidence of BSI in patients with axillary-placed IABP and evaluate its impact on patient outcomes.

Methods

We retrospectively reviewed 141 patients that underwent axillary IABP placement from May 2016 through August 2020. The primary endpoint was the incidence of BSI during axillary IABP, reported as the proportion of patients who developed a BSI and BSI per 1000-device days.

Results

BSI occurred in 13% of patients and accounted for 4.3 infections per 1000-device days. Prior femoral device use and longer duration of axillary IABP support occurred more frequently in the BSI cohort. Presence of traditional BSI risk factors including central line days, use of parenteral nutrition, and prior positive cultures did not differ between those who developed BSI and those who did not. The rate of end-outcome attainment (transplant, LVAD, recovery) was not statistically different in those that developed BSI vs not (72% vs 88% p=0.08). A total of 41% of BSI were caused by Staphylococcus epidermidis. Use of peri-procedural antimicrobials was associated with lower risk of BSI development (24% vs 8%; p=0.01)

Conclusion

Patients in cardiogenic shock requiring use of life-saving temporary mechanical support pose a challenge to maintain free of BSI during prolonged support with an indwelling catheter that allows for ambulation and movement. Mitigation of modifiable BSI risk factors, such as the use of peri-procedural antimicrobial prophylaxis, accompanied by a low threshold for screening and treatment are reasonable strategies to improve patient outcomes. Future research is needed to further evaluate BSI risk in this patient population and its subsequent impact on patient outcomes.

Disclosures

All Authors: No reported disclosures.

Combined Heart-Kidney Transplantation: Indications, Outcomes, and Controversies

Renal dysfunction, a prevalent comorbidity in advanced heart failure, is associated with significant morbidity and mortality after heart transplantation. In the recent era, the field of combined heart-kidney transplantation has experienced great success in the treatment of both renal and cardiac dysfunction in end-stage disease states, and the number of transplants has increased dramatically. In this review, we discuss appropriate indications and selection criteria, overall and organ-specific outcomes, and future perspectives in the field of combined heart-kidney transplantation.

Tissue plasminogen activator in left ventricular assist device-related intravascular hemolysis after failed augmented anticoagulation

OBJECTIVES

We sought to examine the efficacy and safety of adding fibrinogen-guided low-dose multi-day Alteplase™ tissue plasminogen activator (tPA) in the management of intravascular hemolysis (IVH) in patients with the HeartMate II (HM-II) continuous flow (CF) left ventricular assist device (LVAD) who failed to achieve IVH resolution with conventional augmented anticoagulation (AAC).

BACKGROUND

IVH in patients with LVAD is often treated with AAC, failing which pump exchange is considered. We hypothesized that a trial of low-dose tPA after failed AAC therapy could resolve IVH and prevent pump exchange in some patients.

METHODS

We performed a retrospective study of 31 HM-II CF LVAD patients admitted to our center from January 2015 to January 2020 for IVH management who received tPA following failed AAC. Primary 6-month outcomes included successful IVH resolution, unsuccessful IVH resolution requiring pump exchange, gastrointestinal bleeding, ischemic and hemorrhagic cerebrovascular accident (CVA), and death.

RESULTS

Thirty-one patients with IVH were treated with tPA following failed AAC. Successful resolution of IVH occurred in 22/31 (71%) patients. Pump exchange occurred in 9/31 (29%) patients. Gastrointestinal bleeding occurred in 7/31 (22.6%) patients. Ischemic CVA occurred in 6/31 (19.4%) patients.

CONCLUSIONS

Management of IVH with administration of low-dose tPA after failed AAC is feasible and may prevent pump exchange in some patients.

Abstract P2023: Non-cardiomyocytes From Chronic Unloaded Post LVAD Heart Form Organized Complex Neovascular Structures When Compared To Those From Heart Failure

Introduction: Chronic unloading of the left ventricle (LV) has shown increased endothelial density suggestive of a vascular recovery. Mechanisms of such neovascularization have not been fully explored.

Hypothesis: Non-myocyte transitions may play a role in neovascularization in cardiac recovery.

Methods: We utilized fresh cardiac tissue obtained from patients at the time of LVAD (pre-LVAD core - representing HF) and from a LVAD patient at the time of transplant (Post-LVAD-representing chronic unloaded heart). Using disaggregation, cardiac non-myocytes were isolated, and the resulting pellet of cardiac non-myocytes was divided and plated in both fibroblast (FGM) and endothelial (EGM) growth media.

Results: Cells from post-LVAD patient in EGM (grown on glass coverslip) showed a complex organizational network with the presence of CD31+ cells in vessel like structures surrounded by vimentin positive cells (See Figure). These networks were not observed in any of the other culture conditions. We also observed that cells from post-LVAD grew much faster compared to pre-LVAD cells.

Conclusions: To our knowledge, this is the first-time disaggregated cells from human heart samples have been studied in culture. These preliminary observations support the ability of non-cardiomyocytes in a chronic unloaded and rested heart to form neovascular structures not seen in cells from the diseased state of heart failure. This platform can serve to further understand the behavior and role of complex non-myocyte interactions in cardiac recovery.

Abstract P2103: Cannabidiol Protects Cardiac Function In Vivo And Inhibits Endothelial-to-mesenchymal Transition In Vitro : A Potential Anti-fibrotic Therapy For Heart Failure

Introduction: Cannabidiol (CBD) has been investigated for application in various diseases including cardiovascular ailments. Endothelial-to-Mesenchymal transition (EndoMT) has been reported to contribute to cardiac fibrosis and eventually heart failure (HF). Here we demonstrate that both free (f) and nanoparticle encapsulated (n) CBD preserves cardiac function in a non-ischemic mouse model of HF. Further, we show that CBD inhibits EndoMT in vitro .

Hypothesis: CBD administration will improve cardiac function by targeting anti-fibrotic mechanisms.

Methods: HF was induced in a 3-month old C57BL/6J mice (n=3) with 1% NaCl, 0.3 mg/mL L-NAME and an osmotic pump infusion of angiotensin II (Ang II). Both fCBD and nCBD were administered twice per week subcutaneously and echocardiography and histology evaluated at 5 weeks. We used an in vitro EndoMT model with L-NAME+ Ang II as EndoMT inducers in HUVECs. CBD at 0.1, 1 and 2 μM was used to study the dose impact.

Results: HF mice treated with fCBD, and nCBD exhibited significantly higher EF when compared to untreated HF mice (Fig. 1 A). Histological evaluation showed that nCBD treated group displayed a higher anti-fibrotic activity compared to fCBD (both with less fibrosis compared to HF mice) (Fig. 1 B). In vitro , when CBD was added during EndoMT induction, the transition process was inhibited. Immunofluorescence studies exhibited a dose dependent effect of CBD in inhibiting Vimentin (mesenchymal marker) expression during the EndoMT process (Fig. 1 C).

Conclusion: In conclusion, CBD protects cardiac function and exhibits an anti-fibrotic effect, possibly mediated by EndoMT inhibition. A nano formulation of CBD might have a more potent impact.

Abstract P2060: Comprehensive Analysis Of 3’ End Sequencing Reveals Novel Polyadenylation Signals In Human Left Ventricle Failure

Background: Alternative polyadenylation (APA) regulates the genes post-transcriptionally and generates mRNA isoforms with different lengths of 3’ untranslated regions (3’UTR). APA dictates diverse cellular processes such as development, differentiation, metabolism, and protein localization. The dysregulation of APA leading to global 3’UTR changes has been well studied in several human diseases including cancer. However, the role of APA in the progression of cardiac fibrosis and eventually the left ventricle (LV) heart failure in patients remains elusive.

Objective: To identify whether APA regulates the 3’UTR length in the failing LV hearts compared to the healthy hearts.

Methods and Results: We used Poly(A)-Click-Seq to sequence the 3’ end of the transcripts and the PolyA-miner algorithm to comprehensively quantify the APA events in healthy and failing human LV specimens. We used the Poly-A index, a metric that determines the magnitude and position of the 3’UTR changes, to determine the shortening versus lengthening of 3′UTRs. Based on these scores, we identified more than 1000 genes with a significant shift in cleavage site usage in failing LV hearts compared to healthy. Moreover, the enrichment of these differentially regulated APA candidates revealed pathways involved in the progression of heart failure and molecular functions related to mRNA binding. So, by examining the differential polyadenylation events in these hearts, we identified disease-specific APA signatures. In addition, we also found the dysregulation in the core APA machinery proteins such as cleavage factor Im (CFIm) 25, 59, and 68 in the LV failing hearts compared to the healthy.

Conclusion: Hence, we demonstrated that the regulation of the 3’UTR length through APA provides an extra layer of gene expression in human LV failure. Our results provide genome-wide polyadenylation maps of the human heart and show that APA of mRNA is dynamic in the progression of LV failure.

Subjective Financial Hardship from Medical Bills Among Patients with Heart Failure in the United States: The 2014-2018 Medical Expenditure Panel Survey

BACKGROUND

Heart failure (HF) poses a substantial economic burden to the United States (US) healthcare system. In contrast, little is known about the financial challenges faced by patients with HF. In this study, we examined the scope and sociodemographic predictors of subjective financial hardship from medical bills in patients with HF.

METHODS

In the Medical Expenditure Panel Survey (MEPS; years 2014-2018), a US nationally representative database, we identified all patients who reported having HF. Any subjective financial hardship from medical bills was assessed based on patients reporting either themselves or their families 1) having difficulties paying medical bills in the past 12 months, 2) paid bills late, or 3) unable to pay bills at all. Logistic regression was used to evaluate independent predictors of financial hardship among patients with HF. All analyses took into consideration the survey's complex design.

RESULTS

A total of 116,563 MEPS participants were included in the analysis, of whom 858 (0.7%) had a diagnosis of HF, representing 1.8 million (95% CI 1.6 to 2.0) patients annually. Overall, 33% (95% CI 29% to 38%) reported any financial hardship from medical bills with 13.2% not being able to pay bills at all. Age ≤65 years and lower educational attainment were independently associated with higher odds of subjective financial hardship from medical bills.

CONCLUSION

Subjective financial hardship is a prevalent issue among patients with HF in the US, particularly those who are younger and have lower educational attainment. There is a need for policies that reduce out-of-pocket costs in the care of HF, an enhanced identification of this phenomenon in the clinical setting, and approaches to help minimize financial toxicity in patients with HF while ensuring optimal quality of care.

An In Vitro Platform to Study Reversible Endothelial-to-Mesenchymal Transition

Endothelial cells can acquire a mesenchymal phenotype in response to external stimuli through both mechanical and biological factors, using a process known as endothelial-to-mesenchymal (EndoMT) transition. EndoMT is characterized by the decrease in endothelial characteristics, increase in mesenchymal markers, and morphological changes. It has been recognized not only during development but also in different pathological conditions including organ/tissue fibrosis in adults. The ability to modulate the EndoMT process could have a therapeutic potential in many fibrotic diseases. An in vitro method is presented here to induce EndoMT with Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME) and angiotensin II (Ang II) followed by a protocol to study the reversibility of EndoMT. Using this method, we furnish evidence that the combination of L-NAME and Ang II can stimulate EndoMT in Human umbilical vascular endothelial cells (HUVECs) and this process can be reversed as observed using endothelial functionality assays. This method may serve as a model to screen and identify potential pharmacological molecules to target and regulate the EndoMT process, with applications in drug discovery for human diseases.

Ambulatory factors influencing pulmonary artery pressure waveforms and implications for clinical practice

CardioMEMS, a remote pulmonary artery pressure monitoring system, provides waveform patterns for the ambulatory heart failure patient. These waveforms provide significant insights into patient volume and clinical management. We aim to provide a foundation for understanding the determinants of waveform characteristics and provide practical examples illustrating how to interpret and integrate common scenario waveforms into clinical decision-making. A total of three groups of relevant scenarios were included namely (a) location and activity at time of waveform transmission, (b) impact of contemporary interventions, and (c) arrhythmias. We illustrate that waveform analysis can be individualized to each patient's care strategy in the appropriate clinical context to help guide clinical decision-making.

Inflammatory Cardiomyopathies

We present 3 cases of inflammatory cardiomyopathies illustrating the need for a multimodality imaging and multidisciplinary approach for diagnosis and treatment. (Level of Difficulty: Intermediate.)

New Onset Coronary Obstruction in Established Nonischemic Heart Failure: A Late Consequence of Radiation

The column in this issue is provided by Salil Kumar, MD, and Joe Aoun, MD, chief cardiology fellows in the Houston Methodist Cardiology Department, and Arvind Bhimaraj, MD, associate professor of Clinical Cardiology at the Houston Methodist Academic Institute. Dr. Bhimaraj specializes in cardiovascular disease and advanced heart failure and transplantation.

Long term development of diastolic dysfunction and heart failure with preserved left ventricular ejection fraction in heart transplant recipients

Heart transplant recipients (HTX) have several risk factors for heart failure which can trigger pro-inflammatory and fibrosis factors and set into motion pathophysiologic changes leading to diastolic dysfunction and HFpEF. The objective of the study was to determine if HTX recipients with dyspnea have diastolic dysfunction and HFpEF. Twenty-five HTX were included. LV systolic and diastolic functions were evaluated using conductance catheters to obtain pressure volume loops. LV function was assessed at rest and during moderate intensity exercise of the upper extremities. A significant increase occurred in LV minimal pressure (3.7 ± 3.3 to 6.5 ± 3.5 mmHg) and end diastolic pressure or EDP (11.5 ± 4 to 18 ± 3.8 mmHg, both P < 0.01) with exercise. With exercise, the time constant of LV relaxation shortened in 2, was unchanged in 3, and increased in the remaining patients (group results: rest 40 ± 11.6 vs 46 ± 9 ms, P < 0.01). LV chamber stiffness constant was abnormally increased in all but 2 patients. Indices of LV systolic properties were normal at rest but failed to augment with exercise. In 15 who agreed to blood draw, inflammation and fibrosis markers were obtained. A significant association was observed between LV EDP and Pro-Col III N-terminal (r = 0.58, P = 0.024) and IL-1-soluble receptor (r = 0.59, P = 0.02) levels. HTX have diastolic dysfunction and can develop HFpEF several years after cardiac transplantation. The abnormally increased LV chamber stiffness and the prolongation or lack of shortening of the time constant of LV relaxation with exercise are the underlying reasons behind the observed changes in LV diastolic pressures with exercise.

Early humoral immune response to two doses of severe acute respiratory syndrome coronavirus 2 vaccine in a diverse group of solid organ transplant candidates and recipients

Response to two doses of a nucleoside-modified messenger ribonucleic acid (mRNA) vaccine was evaluated in a large solid-organ transplant program. mRNA COVID-19 vaccine was administered to transplant candidates and recipients who met study inclusion criteria. Qualitative anti-SARS-CoV-2 Spike Total Immunoglobulin (Ig) and IgG-specific assays, and a semi-quantitative test for anti-SARS-CoV-2 Spike protein IgG were measured in 241 (17.2%) transplant candidates and 1,163 (82.8%) transplant recipients; 55.2% of whom were non-Hispanic White and 44.8% identified as another race. Transplant recipients were a median (IQR) of 3.2 (1.1, 6.8) years from transplantation. Response differed by transplant status: 96.0% vs 43.2% by the anti-SARS-CoV-2 Total Ig (candidates vs recipients, respectively), 93.5% vs 11.6% by the anti-SARS-CoV-2 IgG assay, and 91.9% vs 30.1% by anti-spike titers after two doses of vaccine. Multivariable analysis revealed candidates had higher likelihood of response vs recipients (odds ratio [OR], 14.6; 95 %CI 2.19, 98.11; p = 0.02). A slightly lower response was demonstrated in older patients (OR 0.96; 95 %CI 0.94, 0.99; p = 0.002), patients taking antimetabolites (OR, 0.21; 95% CI 0.08, 0.51; p = 0.001). Vaccination prior to transplantation should be encouraged. This article is protected by copyright. All rights reserved.

Corticosteroids in Immunosuppression

Corticosteroids have been utilized as mainstay pharmacological intervention for successful organ transplantation since the beginning. Several challenges exist in establishing a balance between achieving a tolerant atmosphere in the host immune system while minimizing the long-term impact of steroids on the body. Corticosteroids are used early in all solid organ transplantation but there is wide variability across various organs and centers in the duration of use and protocols of planned steroid wean. The adverse event profile of steroids is exhaustive and across many organ systems.

Outcomes of Heart Transplant Recipients with Class II Obesity: A United Network for Organ Sharing Database Analysis

BACKGROUND

In the 2016 ISHLT listing criteria guidelines for heart transplantation, recipients were recommended to have a body mass index (BMI) <35 kg/m². However, outcomes data for subgroups of transplant recipients with a BMI >35 kg/m² are limited. We examined the outcomes of heart transplant recipients who had a BMI of 35 to 39.9 kg/m² or ≥40 kg/m² and compared their outcomes with recipients who had a BMI <35 kg/m².

METHODS

Using data from the United Network for Organ Sharing database, we performed a retrospective cohort analysis of 23,009 adults who underwent cardiac transplantation between 2009 and 2018. Transplant recipients were stratified by BMI categories (<35 kg/m², 35-39.9 kg/m², and ≥40 kg/m²). Patient survival was depicted by Kaplan-Meier curves. Cox proportional-hazards modeling was used to determine the prognostic factors associated with mortality within 90 days, 1 year, and 5 years after transplantation.

RESULTS

Survival at 90 days, 1 year, and 5 years after transplantation was better in recipients who had a BMI <35 kg/m² than in those who had a BMI of 35 to 39.9 kg/m² (P values ranged from 0.01 to < 0.001) or ≥40 kg/m² (P < 0.001). Additionally, survival at 90 days (P < 0.001) and 1 year (P = 0.002) was significantly better in recipients who had a BMI of 35 to 39.9 kg/m² than in those who had a BMI ≥40 kg/m². In multivariate analysis, a BMI of 35 to 39.9 was significantly associated with increased 90-day mortality (HR = 1.53; 95% CI 1.12, 2.08; P = 0.01) but not increased 1-year (HR = 1.28; 95% CI 0.99, 1.66; P = 0.06) or 5-year mortality (HR = 1.11; 95% CI 0.91, 1.36; P = 0.29).

CONCLUSIONS

Although heart transplant recipients with class II obesity (BMI 35-39.9 kg/m²) may have suboptimal survival compared with those who have a BMI <35 kg/m², these patients have better outcomes than do those with class III obesity (BMI ≥40 kg/m²). Thus, contrary to current guidelines, selected patients with class II obesity should be considered for transplantation.

Refractory Impella Suction Alarms in the Setting of Extracorporeal Membrane Oxygenation

Cardiogenic shock is an uncommon but serious complication of acute myocardial infarction. Temporary mechanical circulatory support devices are being used more often in this setting, and physicians are required to be familiar with their complications. Although veno-arterial extracorporeal membrane oxygenation increases after loading, an Impella device can be inserted to unload the left ventricle and decrease its oxygen consumption. Here, we present an uncommon cause of a refractory Impella suction alarm, which was related to the migration of the venous extracorporeal membrane oxygenation cannula into the left atrium.

A multi-institutional retrospective analysis on impact of RV acute mechanical support timing after LVAD implantation on 1-year mortality and predictors of RV acute mechanical support weaning

BACKGROUND

There is little insight into which patients can be weaned off right ventricular (RV) acute mechanical circulatory support (AMCS) after left ventricular assist device (LVAD) implantation. We hypothesize that concomitant RV AMCS insertion instead of postoperative implantation will improve 1-year survival and increase the likelihood of RV AMCS weaning.

METHODS

A multicenter retrospective database of 826 consecutive patients who received a HeartMate II or HVAD between January 2007 and December 2016 was analyzed. We identified 91 patients who had early RV AMCS on index admission. Cox proportional-hazards model was constructed to identify predictors of 1-year mortality post-RV AMCS implantation and competing risk modeling identified RV AMCS weaning predictors.

RESULTS

There were 91 of 826 patients (11%) who required RV AMCS after CF-LVAD implantation with 51 (56%) receiving a concomitant RV AMCS and 40 (44%) implanted with a postoperative RV AMCS during their ICU stay; 48 (53%) patients were weaned from RV AMCS support. Concomitant RV AMCS with CF-LVAD insertion was associated with lower mortality (HR 0.45 [95% CI 0.26-0.80], p = 0.01) in multivariable model (which included age, BMI, angiotensin-converting enzyme inhibitor use, and heart transplantation as a time-varying covariate). In the multivariate competing risk analysis, a TPG < 12 (SHR 2.19 [95% CI 1.02-4.70], p = 0.04) and concomitant RV AMCS insertion (SHR 3.35 [95% CI 1.73-6.48], p < 0.001) were associated with a successful wean.

CONCLUSIONS

In patients with RVF after LVAD implantation, concomitant RV AMCS insertion at the time of LVAD was associated with improved 1-year survival and increased chances of RV support weaning compared to postoperative insertion.

Abstract P506: Sirt6 Overexpression Inhibits Senescence And Inflammation In Human Mesenchymal Stem Cells

Background: Mesenchymal Stem Cells (MSCs) offer regenerative and therapeutic potential in an injured tissue in diabetic conditions. But the functional efficiency of MSCs has been shown to decrease with diabetes and aging. This reduces the potential of cell-based therapy in diabetic patients. Recent studies have established the role of sirtuin family proteins in metabolic disease, inflammation, longevity, and DNA repair. However, their potential to be used as a therapeutic target in cardiomyopathy and heart failure remain unexplored.

Objective: To investigate the role of Sirtuin 6 (SIRT6) in mesenchymal stem cells senescence and cardiac regeneration.

Methods and Results: We performed genomics and proteomics in the human control and diabetic heart tissues collected from the heart transplant. Human MSCs were treated with high glucose and mouse MSCs were derived from the bone marrow of diabetic db/db mice for this study. We found that SIRT6 expression is reduced in the myocardium of diabetic patients compared to non-diabetic controls. The SIRT6 expression decreased in high glucose-treated human MSCs compared to mannitol-treated control MSCs as well as in db/db mice MSCs compared to control mice MSCs. These high glucose-treated human MSCs and db/db mice MSCs showed increased expression of senescence and inflammation-related markers like that in diabetic human myocardium. Furthermore, we used small interfering RNA (SIRT6-siRNA) in human MSCs to knock down the SIRT6 gene and validated our findings. Indeed, the knockdown of SIRT6 promoted senescence and inflammation in those MSCs. Finally, we used adeno-associated viruses (AAV-SIRT6) to overexpress SIRT6 in MSCs treated with high glucose and performed proteomic analysis. SIRT6 overexpression in high glucose-treated MSCs reduced the expression of senescence and inflammation related genes and proteins.

Conclusion: Our results highlight the importance of SIRT6 in diabetic myocardium and its role in balancing senescence and inflammation in MSCs. The validation of such in vitro studies in a diabetic mouse model ( db/db ) along with transplantation of SIRT6 overexpressed db/db MSCs into the myocardium of diabetic mice could open doors to successfully use MSC therapy in diabetic patients in the future.

Abstract P507: Comprehensive Characterization Of Poly(a)-clickseq Data Sets Reveal Novel Polyadenylation Signals In Human Right Ventricle Failure

Background: Many human genes hold more than 1 poly(A) site, and polyadenylation gives rise to transcripts with different 3′ untranslated regions (3’UTR) lengths, and this process known as alternative polyadenylation (APA). It plays a significant role in many cellular processes and dysregulation of APA leads to many human diseases. However, the functional consequences of APA events in the right ventricle (RV) failure in humans remain unexplored.

Objective: To understand whether a global APA event is presented in the progression of RV failure by using the novel algorithm PolyA miner in the RV of healthy donors and patients with RV failure.

Methods and Results: RV tissue samples were obtained from failing human hearts at the time of cardiac transplantation at the Houston Methodist DeBakey Heart & Vascular Center, Houston Methodist Hospital. The RV tissues were immediately frozen in liquid nitrogen and stored at –80°C until use. Normal tissue samples were obtained from donor hearts that were not used for transplantation and were collected and stored in the same manner. We characterized the APA profiles of RV failing patients and compared them to healthy RV specimens by using Poly(A)-ClickSeq (PAC-seq) RNA sequencing and the PolyA-miner algorithm. We determined shortening versus lengthening of 3′UTRs based on the PolyA index, a metric unit that determines the length of 3′UTR. Based on these scores, we identified 435 transcripts with a significant shift in cleavage site usage. Further, we discovered 3'UTR shortening and lengthening of many genes in failing RV compared to healthy RV specimens. By examining polyadenylation events in these hearts, we identified disease-specific APA signatures in many genes. In addition, differential APA events in RV failure regulate many pathways important for the progression of the RV failure.

Conclusions: Our study highlights the important roles for APA in human RV failure, including reforming multiple pathways and regulating specific gene expression, representing the complex interplay between APA and other biological processes in the RV failure.