Trends and Outcomes of Left Ventricular Assist Device Therapy: JACC Focus Seminar

Analysing online forums to identify information needs and knowledge gaps in patients with left ventricular assist devices: a qualitative study

AIMS

The aim of the study was to explore the knowledge and unmet informational needs of candidates for left ventricular assist device (LVAD), as well as of patients, caregivers, and family members, by analysing social media data from the MyLVAD.com website.

METHODS AND RESULTS

A qualitative content analysis method was employed, systematically examining and categorizing forum posts and comments published on the MyLVAD.com website from March 2015 to February 2023. The data were collected using an automated script to retrieve threads from MyLVAD.com, focusing on genuine questions reflecting information and knowledge gaps. The study received approval from an ethics committee. The research team developed and continuously updated categorization matrices to organize information into categories and subcategories systematically. From 856 posts and comments analysed, 435 contained questions representing informational needs, of which six main categories were identified: clothing, complications/adverse effects, LVAD pros and cons, self-care, therapy, and recent LVAD implantation. The self-care category, which includes managing the driveline site and understanding equipment functionality, was the most prominent, reflecting nearly half of the questions. Other significant areas of inquiry included complications/adverse effects and the pros and cons of LVAD.

CONCLUSION

The analysis of social media data from MyLVAD.com reveals significant unmet informational needs among LVAD candidates, patients, and their support networks. Unlike traditional data, this social media-based research provides an unbiased view of patient conversations, offering valuable insights into their real-world concerns and knowledge gaps. The findings underscore the importance of tailored educational resources to address these unmet needs, potentially enhancing LVAD patient care.

Survival of a patient following initial left ventricular assist device implantation and two successive left ventricular assist device exchanges: case report

Background

Initially conceptualized as a bridge to heart transplantation, the left ventricular assist device (LVAD) has become an important option for improving survival in patients with severe heart failure and poor prognosis.

Case summary

We report the case of a patient suffering from severe chronic heart failure, complicated by ST-elevation myocardial infarction due to left main coronary artery stenosis (NYHA IV, INTERMACS profile 1). Despite support with veno-arterial extracorporeal membrane oxygenation, inotropes, and catecholamine therapy, the patient's cardiac function did not recover sufficiently. Consequently, the decision was made to proceed with LVAD implantation as destination therapy. The initial LVAD implantation was uneventful, and the patient received anticoagulant therapy according to standard operating procedure. However, pump thrombosis occurred on the first post-operative day, necessitating an LVAD exchange. Following an extended stay in the cardiac surgery intensive care unit, the patient was eventually discharged. Approximately 15 months later, the patient developed a driveline infection, involving most of the intrapericardial components of the LVAD. A second LVAD exchange was required, and the patient received a third LVAD. To mitigate the risk of recurrent infection, suppressive antibiotic therapy with ampicillin/sulbactam was initiated.

Discussion

This is the first reported case of a patient surviving three LVAD implantations and highlights an instance of off-label use of lifelong antibiotic therapy following a driveline infection.

Preoperative anatomical landmarks and longitudinal HeartMate 3 pump position in X-rays: Relevance for adverse events

BACKGROUND

Left ventricular assist device (LVAD) malposition has been linked to hemocompatibility-related adverse events (HRAEs). This study aimed to identify preoperative anatomical landmarks and postoperative pump position, associated with HRAEs during LVAD support.

METHODS

Pre- and postoperative chest X-ray measures (≤14 days pre-implantation, first postoperative standing, 6, 12, 18, and 24 months post-implantation) were analyzed for their association with HRAEs over 24 months in 33 HeartMate 3 (HM3) patients (15.2% female, age 66 (9.5) years).

RESULTS

HM3 patients with any HRAE showed significantly lower preoperative distances between left ventricle and thoracic outline (dLVT) (25.3 ± 10.2 mm vs. 40.3 ± 15.5 mm, p = 0.004). A ROC-derived cutoff dLVT ≤ 29.2 mm provided 85.7% sensitivity and 72.2% specificity predicting any HRAE during HM3 support (76.2% (>29.2 mm) vs. 16.7% (≤29.2 mm) freedom from HRAE, p < 0.001) and significant differences in cardiothoracic ratio (0.58 ± 0.04 vs. 0.62 ± 0.04, p = 0.045). Postoperative X-rays indicated lower pump depths in patients with ischemic strokes (9.1 ± 16.2 mm vs. 38.0 ± 18.5 mm, p = 0.007), reduced freedom from any neurological event (pump depth ≤ 28.7 mm: 45.5% vs. 94.1%, p = 0.004), and a significant correlation between pump depth and inflow cannula angle (r = 0.66, p < 0.001). Longitudinal changes were observed in heart-pump width (F(4,60) = 5.61, p < 0.001).

CONCLUSION

Preoperative X-ray markers are associated with postoperative HRAE occurrence. Applying this knowledge in clinical practice may enhance risk stratification, guide therapy optimization, and improve HM3 recipient management.

HeartMate 3: Analysis of Outcomes and Future Directions

Heart failure (HF) remains a public health concern affecting millions of individuals worldwide. Despite recent advances in device-related therapies, the prognosis for patients with chronic HF remains poor with significant long-term risk of morbidity and mortality. Left ventricular assist devices (LVADs) have transformed the landscape of advanced HF management, offering circulatory support as destination therapy or as a bridge for heart transplantation. Among the latest generation of LVADs, the HeartMate 3 has gained popularity due to improved clinical outcomes and lower risk of serious adverse events when compared with previous similar devices. The ELEVATE (Evaluating the HeartMate 3 with Full MagLev Technology in a Post-Market Approval Setting) Registry and the MOMENTUM 3 (Multicenter Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3) trial represent landmark investigations into the performance and comparative effectiveness of the HeartMate 3 LVAD. This review provides a comprehensive synthesis of the safety and efficacy of the 2-year and 5-year HeartMate LVAD outcomes, highlighting key findings, methodological considerations, implications for clinical practice, and future directions.

The renin-angiotensin-aldosterone system: An old tree sprouts new shoots

The intricate physiological and pathological diversity of the Renin-Angiotensin-Aldosterone System (RAAS) underpins its role in maintaining bodily equilibrium. This paper delves into the classical axis (Renin-ACE-Ang II-AT1R axis), the protective arm (ACE2-Ang (1-7)-MasR axis), the prorenin-PRR-MAP kinases ERK1/2 axis, and the Ang IV-AT4R-IRAP cascade of RAAS, examining their functions in both physiological and pathological states. The dysregulation or hyperactivation of RAAS is intricately linked to numerous diseases, including cardiovascular disease (CVD), renal damage, metabolic disease, eye disease, Gastrointestinal disease, nervous system and reproductive system diseases. This paper explores the pathological mechanisms of RAAS in detail, highlighting its significant role in disease progression. Currently, in addition to traditional drugs like ACEI, ARB, and MRA, several novel therapeutics have emerged, such as angiotensin receptor-enkephalinase inhibitors, nonsteroidal mineralocorticoid receptor antagonists, aldosterone synthase inhibitors, aminopeptidase A inhibitors, and angiotensinogen inhibitors. These have shown potential efficacy and application prospects in various clinical trials for related diseases. Through an in-depth analysis of RAAS, this paper aims to provide crucial insights into its complex physiological and pathological mechanisms and offer valuable guidance for developing new therapeutic approaches. This comprehensive discussion is expected to advance the RAAS research field and provide innovative ideas and directions for future clinical treatment strategies.

Interventional therapies for chronic heart failure: An overview of recent developments

Heart failure (HF), the final manifestation of most cardiovascular diseases, has become a major global health concern, affecting millions of individuals. Despite basic drug treatments, patients present with high morbidity and mortality rates. However, recent advancements in interventional therapy have shown promising results in improving the prognosis of patients with HF. These advancements include transcatheter aortic valve replacement for severe aortic stenosis, transcatheter mitral valve repair for chronic mitral regurgitation, neuromodulation therapy for multiple targets and measures in the treatment of chronic HF and left ventricular assist device implantation for advanced HF (Figure 1). In this review, we aimed to provide an overview of the current progress in interventional therapies for chronic HF.

Outcome Through the Years of Left-Ventricular Assist Devices Therapy for End-Stage Heart Failure: A Review

Heart transplantation remains the gold standard surgical treatment for advanced heart failure. Over time, medical therapies have achieved remarkable outcomes in terms of survival and quality of life, yet their results may be insufficient, even when maximized. The limited availability of organ donors and the selective criteria for heart transplant eligibility have led to a significant rise in the utilization of long-term mechanical circulatory support, including left ventricular assist devices. Patients receiving LVADs often present with multiple comorbidities, constituting a highly vulnerable population. Individuals living with LVADs may experience various long-term complications, such as bleeding, driveline infections, neurological events, and right ventricular dysfunction. Fortunately, the development of increasingly biocompatible LVAD devices in recent years has resulted in a notable reduction in these complications. This review aims to summarize the principal complications encountered by patients with LVADs throughout their treatment and the associated daily management strategies.

Prognostic value of repeated peak oxygen uptake measurements in patients with a left ventricular assist device

BACKGROUND

Peak oxygen uptake (pVO2) predicts mortality in patients with heart failure on left ventricular assist device (LVAD) support. This follow-up of the PRO-VAD study examines the prognostic value of repeated pVO2 measurements during long-term follow-up.

METHODS

This multicenter follow-up study included patients from the original PRO-VAD cohort who performed a cardiopulmonary exercise test (CPET) twice. Patients were categorized into 4 groups based on pVO2 levels at the 2 CPETs: low at both tests, low at the first and high at the second test, high at the first and low at the second test, and high at both tests. Low pVO2 was defined as ≤14 ml/kg/min (or ≤12 ml/kg/min if beta-blocker tolerant), while values above these thresholds were considered high. Survival outcomes were analyzed using the Kaplan-Meier method and cause-specific Cox analysis.

RESULTS

The study included 152 patients with repeated CPETs at approximately 6 and 12 months following LVAD implantation. The cohort showed slight but significant pVO2 improvement (median change: 0.4 ml/kg/min, p = 0.04). Persistently high pVO2 (76 patients) was associated with a 5-fold reduction in mortality hazard (hazard ratio [HR] 0.20, p = 0.002), compared with persistently low pVO2 (46 patients). Improvement from low to high pVO2 (21 patients) displayed similar benefits (HR 0.21, p = 0.02).

CONCLUSIONS

pVO2 measurements remain predictive of mortality upon reiteration in patients with LVAD, with changes in pVO2 providing additional prognostic value in identifying patients with an excellent outcome on ongoing LVAD support and in identifying patients requiring further interventions.

[Patient selection for left ventricular assist device implantation. The main problems]

AIM

To analyze the experience of Chazov National Medical Research Center of Cardiology in patient selection for left ventricular assist device (LVAD) implantation.

MATERIALS AND METHODS

901 patients, whose documents were sent to Chazov National Medical Research Center of Cardiology from regional medical and prophylactic institutions, were screened as selection for LVAD implantation. Firstly, all patients underwent transthoracic echocardiography performed according to the extended protocol with a comprehensive assessment of the left and right ventricle size and function. Patients who underwent the screening procedure underwent further examination including both laboratory and instrumental diagnostic methods. In addition, the polyclinic database of patients diagnosed with chronic heart failure (CHF) and dilated cardiomyopathy was also analyzed.

RESULTS

Among 901 screened patients 7.9% were suitable candidates for LVAD implantation and only 23 (2.6%) patients underwent surgery. Among those not eligible for surgery: 208 (29%) patients were not on optimal medical therapy, 15% of patients had indications for other surgical treatment of CHF, 12% of patients had severe right ventricular failure, 9.8% had severe comorbidities, 6.8% of patients refused surgery.

CONCLUSIONS

The main problems of selection for LVAD implantation were: low awareness of doctors about the introduction of new treatment methods, poor quality of transthoracic echocardiography, a large percentage of patients not receiving basic therapy for CHF, untimely referral of patients for other types of surgical treatment.

Resuscitation of patients with durable mechanical circulatory support with acutely altered perfusion or cardiac arrest: A scoping review

BACKGROUND

There is an increasing prevalence of durable mechanical circulatory supported patients in both the in-and-out of hospital communities. The scientific literature regarding the approach to patients supported by durable mechanical circulatory devices who suffer acutely impaired perfusion has not been well explored.

METHODS

The International Liaison Committee on Resuscitation Advanced, Basic, and Pediatric Life Support Task Forces conducted a scoping review of the literature using a population, context, and concept framework.

RESULTS

A total of 32 publications that included patients who were receiving durable mechanical circulatory support and required acute resuscitation were identified. Most of the identified studies were case reports or small case series. Of these, 11 (34.4%) included patients who received chest compressions. A number of studies reported upon delays in the application of chest compressions resulting from complexity due to the expected pulselessness in some patients with continuous flow left-ventricular assist devices as well as from concern regarding potential dislodgement of the mechanical circulatory support device. Three observational studies identified worse outcomes in durable mechanical circulatory support receiving patients with cardiac arrest and acutely impaired perfusion who received chest compressions as compared to those who did not, however those studies were at high risk of bias. Of 226 patients across 11 studies and two published scientific abstracts who sustained cardiac arrest while supported by durable MCS and underwent chest compressions, there were no reported instances of device dislodgement and 71 (31.4%) patients had favorable outcomes.

CONCLUSIONS

There is a scarcity of evidence to inform the resuscitation of patients with durable mechanical circulatory support (MCS) experiencing acute impairment in perfusion and cardiac arrest. Reports indicate that delays in resuscitation often stem from rescuers' uncertainty about the safety of administering chest compressions. Notably, no instances of device dislodgement have been documented following chest compressions, suggesting that the risk of harm from timely CPR in these patients is minimal.

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

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

Peri-operative fever and LVAD: SIRS or impaired right ventricular strain?

BACKGROUND

An inflammatory milieu after left ventricular assist device (LVAD) implantation is associated with multi-organ dysfunction and pre-operative heightened inflammatory state is associated with right ventricular failure after LVAD implantation.

METHODS

We performed a retrospective analysis of 30 LVAD patients in our institution within the last 2 years for the development of fever and compared them to 30 non-LVAD open-heart surgery patients.

RESULTS

Our results suggest that patients undergoing LVAD implantation are more likely to develop fever in the immediate post-operative period compared to other open-heart surgeries. This is independent of pharmacological treatment, age, or ethnical background. Females and obese patients were more likely to develop fever.

CONCLUSION

Patients with right ventricular dysfunction, as demonstrated by elevated central venous pressure (CVP), had the strongest correlation with fever development. These results pose the question if there is a systemic inflammatory response-like phenomenon driven by increased right ventricular dysfunction.

Temporal Analysis in Outcomes of Long-Term Mechanical Circulatory Support: Retrospective Study

BACKGROUND

 Mechanical assist device indications have changed in recent years. Reduced incidence of complications, better survival, and the third generation of mechanical support devices contributed to this change. In this single-center study, we focused on two time periods that are characterized by the use of different types of mechanical support devices, different patient characteristics, and change in the indications.

METHODS

 The data were processed from the European Registry for Patients with Mechanical Circulatory Support (EUROMACS). We retrospectively defined two time intervals to reflect changes in ventricular assist device technology (period 1: 2007-2015; period 2: 2016-20222). A total of 181 patients underwent left ventricular assist device implantation. Device utilization was the following: HeartMate II = 52 (76.4%) and HeartWare = 16 (23.6%) in period 1 and HeartMate II = 2 (1.8%), HeartMate 3 = 70 (61:9%), HeartWare = 29 (25.7%), SynCardia TAH = 10 (8.8%), and BerlinHeart EXCOR = 2 (1.8%) in period 2. The outcomes of the time intervals were analyzed and evaluated.

RESULTS

 Survival was significantly higher during the second time period. Multivariate analysis revealed that age and bypass pump time are independent predictors of mortality. Idiopathic cardiomyopathy, bypass time, and the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) score are independent predictors of adverse events. Furthermore, the first period was noted to be at an increased risk of the following adverse events: pump thrombosis, gastrointestinal bleeding, and bleeding events.

CONCLUSION

 Despite the higher risk profile of the patients and persistent challenges, during the second period, there was a significant decrease in mortality and morbidity. The use of the HeartMate 3 device may have contributed to this result.

Propensity score-based comparison of high-risk coronary artery bypass grafting vs. left ventricular assist device implantation in patients with coronary artery disease and advanced heart failure

Objectives

Revascularization in patients with severely reduced left ventricular function and coronary artery disease (CAD) is associated with a high perioperative risk. In this setting, implantation of a durable left ventricular assist device (LVAD) might be an alternative.

Methods

We retrospectively compared the outcomes of adult patients with CAD and a left ventricular ejection fraction (LVEF) ≤ 25% who underwent coronary artery bypass grafting (CABG) vs. LVAD implantation. Propensity score (PS) matching was performed for statistical analysis, resulting in 168 pairs.

Results

In the PS-matched cohorts, the mean age was 62 years; one third had a history of myocardial infarction, 11% were resuscitated, half of the patients were on inotropic support, and 20% received preoperative mechanical circulatory support. LVAD patients required significantly longer ventilation (58 h [21, 256] vs. 16 h [9, 73], p < 0.001) and had a longer ICU stay (11d [7, 24] vs. 4d [2, 10], p ≤ 0.001) compared to CABG patients The incidence of postoperative renal replacement therapy (2 [1.2%] vs.15 [8.9%], p = 0.002) and temporary mechanical circulatory support was lower in the LVAD group (1 [0.6%] vs. 51 [30.4%], p ≤ 0.001). The in-hospital stroke rate was similar (LVAD 7 [5.4%] vs. CABG 8 [6.2%], p = 0.9). In-hospital survival, 1-year survival, and 3-year survival were 90.5% vs. 85.5% (p = 0.18), 77.4% vs. 68.9% (p = 0.10) and 69.6% vs. 45.9% (p < 0.001), for CABG and LVAD patients respectively.

Conclusion

Patients with CAD and advanced HF demonstrate better mid-term survival if they undergo CABG rather than LVAD implantation.

New Disease Trajectories of Heart Failure: Challenges in Determining the Ideal Timing of Palliative Care Implementation

Background: The disease trajectory of heart failure (HF), along with other organ failures, is still being elucidated. The trajectory is represented as a descending saw-tooth curve, indicating the frequent exacerbations and hospitalizations and slow progression to death. However, the clinical pattern of HF is no longer unique because of the definition of three distinct phenotypes, according to different values of ejection fraction (EF): HF with reduced EF (HFrEF), mildly reduced EF (HFmEF), and preserved EF (HFpEF). Patients with HFrEF have access to pharmacological and nonpharmacological treatments that have been shown to reduce mortality, unlike the other two classes for which no effective therapies are present. Therefore, their disease trajectories are markedly different. Methods: In this study, multiple new disease trajectories of HFrEF are being proposed, ranging from a complete and persistent recovery to rapid clinical deterioration and premature death. These new trajectories pose challenges to early implementation of palliative care (PC), as indicated in the guidelines. Results: From these considerations, we discuss how the improved prognosis of HFrEF because of effective treatment could paradoxically delay the initiation of early PC, especially with the insufficient palliative knowledge and training of cardiologists, who usually believe that PC is required only at the end of life. Conclusions: The novel therapeutic approaches for HF discussed in this study highlight the clinical specificity and peculiar needs of patients with HF. The changing model of disease trajectories of patients with HF will provide new opportunities for the early implementation of PC.

Case Report: Unmasking sustainable left ventricular recovery in chronic heart failure with axillary temporary mechanical circulatory support

Background

Mechanical circulatory support (MCS), temporary or durable, is essential in patients with acute heart failure presenting in cardiogenic shock (CS). MCS is fundamental in patients with advanced heart failure when used as a bridge to decision, transplant or left ventricular recovery. Limited data on acute-on-chronic heart failure (HF) patients exists in the era of axillary mechanical circulatory support with the Impella 5.5. We describe a case of chronic ischemic cardiomyopathy, HF-CS, in a patient who underwent Impella placement, medical optimization, and explant, now with sustained normalization in ejection fraction.

Case summary

A Caucasian female in her 50 s was referred to our center for evaluation for advanced therapies, including transplantation or durable left ventricular assist device placement. Her initial ejection fraction was 30% with comorbidities including multivessel coronary artery disease revascularized with 3 vessel bypass grafting ten years prior, type 2 diabetes (A1c 8.6%), and peripheral vascular disease. During her evaluation, she had acute decompensation leading to cardiogenic shock and required hospitalization with inotrope initiation, which was unable to be weaned. She was approved for organ transplant and listed; however, she required escalation of support and eventual placement of right axillary Impella 5.5. While on Impella support, her vasoactive needs reduced, and she was found to have left ventricular recovery and tolerated the initiation of guideline medical therapy. After three weeks of support, the Impella was weaned and explanted, and the patient was discharged. She remains stable with a sustained ejection fraction of greater than 50% with NYHA class 1 functional status at follow-up. One year later, the patient showed sustained myocardial recovery with guideline-directed medical therapy (GDMT).

Conclusion

Our case highlights a unique approach in patients with long-standing (>5 years) heart failure who may benefit from early consideration for axillary support and concomitant optimization with guideline-directed medical therapy to assess for explant and native heart recovery.

Socio-economic position, multimorbidity, and health care utilization among Danish left ventricular assist device patients

AIMS

Increasing numbers of patients with advanced heart failure and significant comorbidity and social barriers are considered for left ventricular assist devices (LVADs). We sought to examine health care utilization post-LVAD implantation, including the influence of individual-level socio-economic position and multimorbidity.

METHODS AND RESULTS

We conducted a Danish nationwide cohort study linking individual-level data from clinical LVAD databases, the Scandiatransplant Database, and Danish national medical and administrative registries. Socio-economic position included cohabitation status, educational level, and employment status. Multimorbidity was defined as two or more chronic conditions from at least two chronic disease groups. Health care utilization (hospital activity, general practice activity, and redeemed medical prescriptions) within 2 years post-discharge after LVAD implantation was evaluated using descriptive statistics at 0.5 year intervals. We identified 119 patients discharged alive with first-time LVAD implanted between 2006 and 2018. The median age of the patients was 56.1 years, and 88.2% were male. Patients were followed until heart transplantation, LVAD explantation, death, 31 December 2018, or for 2 years. The median follow-up was 0.8 years. The highest median use of health care services was observed 0-0.5 years post-LVAD discharge compared with the subsequent follow-up intervals: 0.5-1, 1-1.5, and 1.5-2 years, respectively. The median (interquartile range) number of hospitalizations was 10 (7-14), bed days 14 (9-28), outpatient visits 8 (5-12), telephone contacts with a general practitioner 4 (2-8), and total redeemed medical prescriptions 26 (19-37) within 0-0.5 years post-LVAD discharge compared with the median utilization within the consecutive follow-up periods [e.g. within 0.5-1 year: hospitalizations 5 (3-8), bed days 8 (4-14), outpatient visits 5 (3-8), telephone contacts 2 (0-5), and redeemed medical prescriptions 24 (18-30)]. The median use of health care services was stable from 0.5 years onwards. The median number of hospitalizations and bed days was slightly higher in patients living alone with a low educational level or low employment status within 0-0.5 years post-LVAD implantation. Finally, the median number of in-hospital days and redeemed prescriptions was higher among patients with pre-existing multimorbidity.

CONCLUSIONS

Among patients who underwent LVAD implantation, health care utilization was high in the early post-LVAD discharge phase and was influenced by socio-economic position. Multimorbidity influenced the number of in-hospital days and redeemed prescriptions during the 2 year follow-up.

Iron Deficiency in Patients with Left Ventricular Assist Devices

Iron deficiency is a common and independent predictor of adverse outcomes in patients with heart failure. The implications of iron deficiency in patients implanted with a left ventricular assist device (LVAD) are less established. This review recaps data on the prevalence, characteristics and impact of Iron deficiency in the LVAD population. A systematic search yielded eight studies involving 517 LVAD patients, with iron deficiency prevalence ranging from 40% to 82%. IV iron repletion was not associated with adverse events and effectively resolved iron deficiency in most patients. However, the effects of iron deficiency and iron repletion on post-implant survival and exercise capacity remain unknown. Although iron deficiency is highly prevalent in LVAD patients, its true prevalence and adverse effects may be misestimated due to inexact diagnostic criteria. Future randomised controlled trials on IV iron treatment in LVAD patients are warranted to clarify the significance of this common comorbidity.

Right Ventriculoarterial Coupling Surrogates and Long-Term Survival in LVAD Recipients: Results of the ASSIST-ICD Multicentric Registry

BACKGROUND

Prediction of outcomes remains an unmet need in candidates for LVADs. The development of right-heart failure portends an excess in mortality rates, but imaging parameters of right ventricular systolic function have failed to demonstrate a prognostic role. By integrating pulmonary pressure, right ventriculoarterial coupling could fill this gap.

METHODS

The ASSIST-ICD registry was used to test right ventriculoarterial coupling as a surrogate parameter at implantation for the prediction of all-cause mortality.

RESULTS

The ratio of the tricuspid annular-plane systolic excursion over the estimated systolic pulmonary pressure (TAPSE/sPAP) was not associated with long-term survival in univariate analysis (P = 0.89), nor was the pulmonary artery pulsatility index (PAPi) (P = 0.13). Conversely, the ratio of the right atrial pressure over the pulmonary capillary wedge pressure (RAP/PCWP) was associated with all-cause mortality (P < 0.01). After taking tricuspid regurgitation severity, LVAD indication, LVAD model, age, blood urea nitrogen levels, and pulmonary vascular resistance into account, RAP/PCWP remained associated with survival (HR 1.35 [1.10 - 1.65]; P < 0.01).

CONCLUSION

Among pre-implant RVAC surrogates, only RAP/PCWP was associated with long-term all-cause mortality in LVAD recipients. This association was independent of established risk factors.

Cardiac magnetic resonance in advanced heart failure

Heart failure (HF) is a chronic and progressive disease that often progresses to an advanced stage where conventional therapy is insufficient to relieve patients' symptoms. Despite the availability of advanced therapies such as mechanical circulatory support or heart transplantation, the complexity of defining advanced HF, which requires multiple parameters and multimodality assessment, often leads to delays in referral to dedicated specialists with the result of a worsening prognosis. In this review, we aim to explore the role of cardiac magnetic resonance (CMR) in advanced HF by showing how CMR is useful at every step in managing these patients: from diagnosis to prognostic stratification, hemodynamic evaluation, follow-up and advanced therapies such as heart transplantation. The technical challenges of scanning advanced HF patients, which often require troubleshooting of intracardiac devices and dedicated scans, will be also discussed.

Validation of the HeartMate 3 survival risk score in a large left ventricular assist device center

OBJECTIVE

The HeartMate 3 survival risk score was recently validated in the Multicenter study Of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3 to predict patient-specific survival in HeartMate 3 left ventricular assist device candidates. The HeartMate 3 survival risk score stratifies individuals into tertiles according to survival probability.

METHODS

We performed a single-center retrospective review of all HeartMate 3 left ventricular assist device recipients between September 2017 and August 2022. Baseline characteristics were collected from the electronic medical records. HeartMate 3 survival risk scores were calculated for all eligible patients. One- and 2-year Kaplan-Meier survival analyses were conducted. A univariate and multivariable Cox regression model was used to identify predictors.

RESULTS

A total of 181 patients were included in this final analysis. The median age was 62 years, 83% were male, and 26% were Interagency Registry for Mechanically Assisted Circulatory Support Profile 1. The mean HeartMate 3 survival risk score for the entire cohort was 2.66 ± 0.66. Two-year survivals in the high, average, and low survival groups were 93.5% ± 3.2%, 81.6% ± 7.4%, and 82.0% ± 6.6%, respectively. As a continuous variable, the unadjusted HeartMate 3 survival risk score was a significant predictor of mortality (hazard ratio, 2.20; 95% CI, 1.08-4.45; P = .029). The areas under the curve were 0.70 and 0.66 at 1 and 2 years, respectively. We were unable to demonstrate the discriminatory ability of the HeartMate 3 survival risk score using the original stratification, but we found significantly increased survival in the high survival group using a binary cutoff (hazard ratio, 4.8; 95% CI, 1.01-20.9; P = .038).

CONCLUSIONS

The unadjusted HeartMate 3 survival risk score was associated with postimplant survival in patients outside of the Multicenter study Of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3 but did not remain an independent predictor after adjusting for ischemic etiology and severe diabetes. The HeartMate 3 survival risk score was able to identify patients at high survival using a binary cutoff, but we were unable to demonstrate its discriminatory ability among the previously published risk tertiles.

Next-Generation Cardiac Interfacing Technologies Using Nanomaterial-Based Soft Bioelectronics

Cardiac interfacing devices are essential components for the management of cardiovascular diseases, particularly in terms of electrophysiological monitoring and implementation of therapies. However, conventional cardiac devices are typically composed of rigid and bulky materials and thus pose significant challenges for effective long-term interfacing with the curvilinear surface of a dynamically beating heart. In this regard, the recent development of intrinsically soft bioelectronic devices using nanocomposites, which are fabricated by blending conductive nanofillers in polymeric and elastomeric matrices, has shown great promise. The intrinsically soft bioelectronics not only endure the dynamic beating motion of the heart and maintain stable performance but also enable conformal, reliable, and large-area interfacing with the target cardiac tissue, allowing for high-quality electrophysiological mapping, feedback electrical stimulations, and even mechanical assistance. Here, we explore next-generation cardiac interfacing strategies based on soft bioelectronic devices that utilize elastic conductive nanocomposites. We first discuss the conventional cardiac devices used to manage cardiovascular diseases and explain their undesired limitations. Then, we introduce intrinsically soft polymeric materials and mechanical restraint devices utilizing soft polymeric materials. After the discussion of the fabrication and functionalization of conductive nanomaterials, the introduction of intrinsically soft bioelectronics using nanocomposites and their application to cardiac monitoring and feedback therapy follow. Finally, comments on the future prospects of soft bioelectronics for cardiac interfacing technologies are discussed.

Heart Transplantation in a Patient With Rheumatic Heart Disease and Severe Left Atrial Calcification

A 62-year-old woman who had undergone mitral valve replacement 24 years ago was admitted to the hospital with congestive heart failure. She needed heart transplantation for stage D heart failure. Preoperative cardiac computed tomographic scans showed a severely calcified left atrium and a large right atrium. Given that the left atrium's calcification was too severe to suture, the calcified left atrial wall was broadly resected, and the resected left atrial wall was reconstructed with a bovine pericardial patch for anastomosis with the donor's left atrial wall. The operation was completed without heavy bleeding, and the patient was discharged from the hospital with no complications.

Status 2 upgrade indication impacts posttransplant mortality in patients bridged with intraaortic balloon pump in the new heart allocation system

To evaluate outcomes of patients undergoing heart transplants (HTs) using an intra-aortic balloon pump (IABP) under exception status. Adult patients supported by an IABP who underwent HT between November 18, 2018, and December 31, 2020, as documented in the United Network for Organ Sharing, were included. Patients were stratified according to requests for exception status. Kaplan-Meier methodology was used to look for differences in survival between groups. A total of 1284 patients were included; 492 (38.3%) were transplanted with an IABP under exception status. Exception status patients had higher body mass index, were more likely to be Black, and had longer waitlist times. Exception status patients received organs from younger donors, had a shorter ischemic time, and had a higher frequency of sex mismatch. The 1-year posttransplant survival was 93% for the nonexception and 88% for the exception IABP patients (hazard ratio: 1.85 [95% confidence interval: 1.12-2.86, P = .006]). The most common reason for requesting an exception status was inability to meet blood pressure criteria for extension (37% of patients). The most common reason for an extension request for an exception status was right ventricular dysfunction (24%). IABP patients transplanted under exception status have an increased 1-year mortality rate posttransplant compared with those without exception status.

Sex-Linked Differences in Cardiac Atrophy After Mechanical Unloading Induced by Heterotopic Heart Transplantation

No information is available about sex-related differences in unloading-induced cardiac atrophy. We aimed to compare the course of unloading-induced cardiac atrophy in intact (without gonadectomy) male and female rats, and in animals after gonadectomy, to obtain insight into the influence of sex hormones on this process. Heterotopic heart transplantation (HT((x)) was used as a model for heart unloading. Cardiac atrophy was assessed as the weight ratio of heterotopically transplanted heart weight (HW) to the native HW on days 7 and 14 after HTx in intact male and female rats. In separate experimental groups, gonadectomy was performed in male and female recipient animals 28 days before HT(x) and the course of cardiac atrophy was again evaluated on days 7 and 14 after HT(x). In intact male rats, HT(x) resulted in significantly greater decreases in whole HW when compared to intact female rats. The dynamics of the left ventricle (LV) and right ventricle (RV) atrophy after HT(x) was quite similar to that of whole hearts. Gonadectomy did not have any significant effect on the decreases in whole HW, LV, and RV weights, with similar results in male and female rats. Our results show that the development of unloading-induced cardiac atrophy is substantially reduced in female rats when compared to male rats. Since gonadectomy did not alter the course of cardiac atrophy after HTx, similarly in both male and female rats, we conclude that sex-linked differences in the development of unloading-induced cardiac atrophy are not caused by the activity of sex hormones.

The Role of Artificial Intelligence and Machine Learning in the Prediction of Right Heart Failure after Left Ventricular Assist Device Implantation: A Comprehensive Review

One of the most challenging and prevalent side effects of LVAD implantation is that of right heart failure (RHF) that may develop afterwards. The purpose of this study is to review and highlight recent advances in the uses of AI in evaluating RHF after LVAD implantation. The available literature was scanned using certain key words (artificial intelligence, machine learning, left ventricular assist device, prediction of right heart failure after LVAD) was scanned within Pubmed, Web of Science, and Google Scholar databases. Conventional risk scoring systems were also summarized, with their pros and cons being included in the results section of this study in order to provide a useful contrast with AI-based models. There are certain interesting and innovative ML approaches towards RHF prediction among the studies reviewed as well as more straightforward approaches that identified certain important predictive clinical parameters. Despite their accomplishments, the resulting AUC scores were far from ideal for these methods to be considered fully sufficient. The reasons for this include the low number of studies, standardized data availability, and lack of prospective studies. Another topic briefly discussed in this study is that relating to the ethical and legal considerations of using AI-based systems in healthcare. In the end, we believe that it would be beneficial for clinicians to not ignore these developments despite the current research indicating more time is needed for AI-based prediction models to achieve a better performance.

CTRP3 alleviates mitochondrial dysfunction and oxidative stress injury in pathological cardiac hypertrophy by activating UPRmt via the SIRT1/ATF5 axis

Pathological cardiac hypertrophy is an independent risk factor for heart failure. Disruption of mitochondrial protein homeostasis plays a key role in pathological cardiac hypertrophy; however, the mechanism of maintaining mitochondrial homeostasis in pathological cardiac hypertrophy remains unclear. In this study, we investigated the regulatory mechanisms of mitochondrial protein homeostasis in pathological cardiac hypertrophy. Wildtype (WT) mice, knockout mice, and mice transfected with lentivirus overexpressing mouse C1q-tumor necrosis factor-related protein-3 (CTRP3) underwent transverse aortic constriction or sham surgery. After 4 weeks, cardiac function, mitochondrial function, and oxidative stress injury were examined. For mechanistic studies, neonatal rat cardiomyocytes were treated with small interfering RNA or overexpression plasmids for the relevant genes. CTRP3 overexpression attenuated transverse aortic constriction (TAC) induced pathological cardiac hypertrophy, mitochondrial dysfunction, and oxidative stress injury compared to that in WT mice. TAC or Ang II resulted in compensatory activation of UPRmt, but this was not sufficient to counteract pathologic cardiac hypertrophy. CTRP3 overexpression further induced activation of UPRmt during pathologic cardiac hypertrophy and thereby alleviated pathologic cardiac hypertrophy, whereas CTRP3 knockout or knockdown inhibited UPRmt. ATF5 was a key regulatory molecule of UPRmt, as ATF5 knockout prevented the cardioprotective effect of CTRP3 in TAC mice. In vitro, SIRT1 was identified as a possible downstream CTRP3 effector molecule, and SIRT1 knockout blocked the cardioprotective effects of CTRP3. Our results also suggest that ATF5 may be regulated by SIRT1. Our study demonstrates that CTRP3 activates UPRmt via the SIRT1/ATF5 axis under pathological myocardial hypertrophy, thus attenuating mitochondrial dysfunction and oxidative stress injury.

Developments and Challenges in Durable Ventricular Assist Device Technology: A Comprehensive Review with a Focus on Advancements in China

Heart transplantation is currently the most effective treatment for end-stage heart failure; however, the shortage in donor hearts constrains the undertaking of transplantation. Mechanical circulatory support (MCS) technology has made rapid progress in recent years, providing diverse therapeutic options and alleviating the dilemma of donor heart shortage. The ventricular assist device (VAD), as an important category of MCS, demonstrates promising applications in bridging heart transplantation, destination therapy, and bridge-to-decision. VADs can be categorized as durable VADs (dVADs) and temporary VADs (tVADs), according to the duration of assistance. With the technological advancement and clinical application experience accumulated, VADs have been developed in biocompatible, lightweight, bionic, and intelligent ways. In this review, we summarize the development history of VADs, focusing on the mechanism and application status of dVADs in detail, and further discuss the research progress and use of VADs in China.

Contemporary National Trends of Mechanical Circulatory Support Among Myocarditis Hospitalizations Before the Pandemic: A National In-patient Database (2005-2019) Study

According to the Global Burden of Disease Project, the morbidity and mortality of myocarditis continue to be a significant worldwide burden. On October 1, 2015, hospital administrative data started using the International Classification of Diseases (ICD)-10 codes instead of the ICD-9. To our knowledge, nationwide trends of myocarditis have not been studied after this update. The NIS database from 2005-2019 was analyzed using ICD-9 and 10 codes. Our search yielded 141,369 hospitalizations due to myocarditis, with 40.9% females. There were 6627 (4.68%) patients who required mechanical circulatory support (MCS) using left ventricular assisted devices (LVAD), intra-aortic balloon pump (IABP), or extracorporeal membrane oxygenation (ECMO). The use of LVAD and ECMO increased significantly during the study period (p-trend 0.003 and <0.001, respectively), whereas the use of IABP decreased during the same period (p-trend 0.025). Our study demonstrated an overall increase in the use of MCS overall in myocarditis, with increasing utilization of more advanced MCS in the forms of LVAD and ECMO.

Left Ventricular Assist Device Implantation with Concomitant Replacement of the Ascending Aorta

Dilated cardiomyopathy (DCM) is one of the main causes for end-stage heart failure. Until the transplantation, left ventricular assist devices (LVAD) have become an established treatment. We report a case of a 66-year-old patient with ischemic and DCM and suspected aortic ulcer formation. LVAD was implanted in the same session with a supracoronary aortic replacement. Bilateral cannulation of the subclavian arteries omitted the need of circulatory arrest and proximal aortic cross-clamping. Pneumonia-associated decarboxylation failure prolonged the postoperative intensive care period. The patient was finally discharged home on the 115 th postoperative day.

2-year outcomes of MitraClip as a bridge to heart transplantation: The international MitraBridge registry

BACKGROUND

In the first report from the MitraBridge registry, MitraClip as a bridge to heart transplantation (HTx) proved to be at 1-year an effective treatment strategy for 119 patients with advanced heart failure (HF) who were potential candidates for HTx. We aimed to determine if benefits of MitraClip procedure as a bridge-to-transplant persist up to 2-years.

METHODS

By the end of the enrollment period, a total of 153 advanced HF patients (median age 59 years, left ventricular ejection fraction 26.9 ± 7.7%) with significant secondary mitral regurgitation, who were potential candidates for HTx and were treated with MitraClip as a bridge-to-transplant strategy, were included in the MitraBridge registry. The primary endpoint was the 2-year composite adverse events rate of all-cause death, first hospitalization for HF, urgent HTx or LVAD implantation.

RESULTS

Procedural success was achieved in 89.5% of cases. Thirty-day mortality was 0%. At 2-year, Kaplan-Meier estimates of freedom from primary endpoint was 47%. Through 24 months, the annualized rate of HF rehospitalization per patient-year was 44%. After an overall median follow-up time of 26 (9-52) months, elective HTx was successfully performed in 30 cases (21%), 19 patients (13.5%) maintained or obtained the eligibility for transplant, and 32 patients (22.5%) no longer had an indication for HTx because of significant clinical improvement.

CONCLUSIONS

After 2-years of follow-up, the use of MitraClip as a bridge-to-transplant was confirmed as an effective strategy, allowing elective HTx or eligibility for transplant in one third of patients, and no more need for transplantation in 22.5% of cases.

The role of innovative modeling and imaging techniques in improving outcomes in patients with LVAD

Heart failure remains a significant cause of mortality in the United States and around the world. While organ transplantation is acknowledged as the gold standard treatment for end stage heart failure, supply is limited, and many patients are treated with left ventricular assist devices (LVADs). LVADs extend and improve patients' lives, but they are not without their own complications, particularly the hemocompatibility related adverse events (HRAE) including stroke, bleeding and pump thrombosis. Mainstream imaging techniques currently in use to assess appropriate device function and troubleshoot complications, such as echocardiography and cardiac computed tomography, provide some insight but do not provide a holistic understanding of pump induced flow alterations that leads to HRAEs. In contrast, there are technologies restricted to the benchtop-such as computational fluid dynamics and mock circulatory loops paired with methods like particle image velocimetry-that can assess flow metrics but have not been optimized for clinical care. In this review, we outline the potential role and current limitations of converging available technologies to produce novel imaging techniques, and the potential utility in evaluating hemodynamic flow to determine whether LVAD patients may be at higher risk of HRAEs. This addition to diagnostic and monitoring capabilities could improve prevention and treatment of LVAD-induced complications in heart failure patients.

Management of hypertension in patients supported with continuous flow left ventricular assist devices

PURPOSE OF REVIEW

Hypertension remains one of the most common clinical problems leading to devastating postleft ventricular assist device (LVAD) implant complications. This study reviews the pathophysiology of hypertension in the setting of continuous flow LVAD support and provides an update on currently available antihypertensive therapies for LVAD patients.

RECENT FINDINGS

The true prevalence of hypertension in the LVAD population remains unknown. Effective blood pressure (BP) control and standardization of BP measurement are key to prevent suboptimal left ventricular unloading, pump malfunction and worsening aortic regurgitation. Angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARB), beta blockers and mineralocorticoid receptor antagonists (MRA) are the preferred antihypertensive agents because of their additional potential benefits, including optimization of haemodynamics, prevention of stroke, gastrointestinal bleed and in some patients myocardial recovery. Angiotensin receptor-neprilysin inhibition (ARNI) may be a well tolerated and effective therapy for BP control especially among CF-LVAD patients with resistant hypertension. Similarly, sodium glucose co-transporter 2 inhibitors (SGLT2i) should be considered in the absence of contraindications.

SUMMARY

Hypertension is very common post-LVAD implant. Heart failure guideline directed medical therapies, including ACEI, ARB, beta blockers and MRA, are the preferred antihypertensive agents to improve post-LVAD outcomes.

Bridging the gap in the symptomatic heart failure patient journey: insights from the Italian scenario

BACKGROUND

The prognosis for heart failure (HF) patients remains poor, with a high mortality rate, and a marked reduction in quality of life (QOL) and functional status. This study aims to explore the ongoing needs of HF management and the epidemiology of patients followed by Italian HF clinics, with a specific focus on cardiac contractility modulation (CCM).

RESEARCH DESIGN AND METHODS

Data from patients admitted to 14 HF outpatients clinics over 4 weeks were collected and compared to the results of a survey open to physicians involved in HF management operating in Italian centers.

RESULTS

One hundred and five physicians took part in the survey. Despite 94% of patients receive a regular follow-up every 3-6 months, available therapies are considered insufficient in 30% of cases. Physicians reported a lack of treatment options for 23% of symptomatic patients with reduced ejection fraction (EF) and for 66% of those without reduced EF. Approximately 3% of HF population (two patients per month per HF clinic) meets the criteria for immediate CCM treatment, which is considered a useful option by 15% of survey respondents.

CONCLUSIONS

Despite this relatively small percentage, considering total HF population, CCM could potentially benefit numerous HF patients, particularly the elderly, by reducing hospitalizations, improving functional capacity and QOL.

Right heart failure after left ventricular assist device implantation: a persistent problem

Left ventricular assist device (LVAD) is an option for bridge-to-transplant or destination therapy for patients with end-stage heart failure. Right heart failure (RHF) remains a complication after LVAD implantation that portends high morbidity and mortality, despite advances in LVAD technology. Definitions of RHF vary, but generally include the need for inotropic or pulmonary vasodilator support, or potential right ventricular (RV) mechanical circulatory support. This review covers the complex pathophysiology of RHF related to underlying myocardial dysfunction, interventricular dependence, and RV afterload, as well as treatment strategies to curtail this challenging problem.

Sex-Associated Differences in the Clinical Outcomes of Left Ventricular Assist Device Recipients: Insights From Interagency Registry for Mechanically Assisted Circulatory Support

BACKGROUND

Sex-associated differences in clinical outcomes among left ventricular assist device recipients in the United States have been recognized. However, an investigation of the social and clinical determinants of sex-associated differences is lacking.

METHODS

Left ventricular assist device receiving patients enrolled in Interagency Registry for Mechanically Assisted Circulatory Support between 2005 and 2017 were included. The primary outcome was all-cause mortality. Secondary outcomes included heart transplantation and postimplantation adverse event rates. The cohort was stratified by the social subgroup of race and ethnicity (non-Hispanic White, non-Hispanic Black, non-Hispanic Asian, and Hispanic), and clinical subgroups of device strategy (destination therapy, bridge to transplant, and bridge to candidacy), and implantation center volume (low [≤20 implants/y], medium [21-30 implants/y], and high [>30 implants/y]). A multivariable-adjusted Cox proportional hazard model was used to assess the risk of death and heart transplantation with prespecified interaction testing. Poisson regression was used to estimate adverse events by sex across the various subgroups.

RESULTS

Among 18 525 patients, there were 3968 (21.4%) females. Compared with their male counterparts, Hispanic (adjusted hazard ratio [HRadj], 1.75 [1.23-2.47]) females had the highest risk of death followed by non-Hispanic White females (HRadj, 1.15 [1.07-1.25]; Pinteraction=0.02). Hispanic (HRadj, 0.60 [0.40-0.89]) females had the lowest cumulative incidence of heart transplantation followed by non-Hispanic Black females (HRadj, 0.76 [0.67-0.86]), and non-Hispanic White females (HRadj, 0.88 [0.80-0.96]) compared with their male counterparts (Pinteraction<0.001). Compared with their male counterparts, females on the bridge to candidacy strategy (HRadj, 1.32 [1.18-1.48]) had the highest risk of death (Pinteraction=0.01). The risk of death (Pinteraction=0.44) and cumulative incidence of heart transplantation (Pinteraction=0.40) did not vary by sex in the center volume subgroup. A higher incidence rate of adverse events after left ventricular assist device implantation was also seen in females compared with the males, overall, and across all subgroups.

CONCLUSIONS

Among left ventricular assist device recipients, the risk of death, the cumulative incidence of heart transplantation, and adverse events differ by sex across the social and clinical subgroups.

Successful Bacteriophage-Antibiotic Combination Therapy against Multidrug-Resistant Pseudomonas aeruginosa Left Ventricular Assist Device Driveline Infection

There is considerable interest in the use of bacteriophages (phages) to treat Pseudomonas aeruginosa infections associated with left ventricular assist devices (LVADs). These infections are often challenging to manage due to high rates of multidrug resistance and biofilm formation, which could potentially be overcome with the use of phages. We report a case of a 54-year-old man with relapsing multidrug-resistant P. aeruginosa LVAD driveline infection, who was treated with a combination of two lytic antipseudomonal phages administered intravenously and locally. Treatment was combined with LVAD driveline repositioning and systemic antibiotic administration, resulting in a successful outcome with clinical cure and eradication of the targeted bacteria. However, laboratory in vitro models showed that phages alone could not eradicate biofilms but could prevent biofilm formation. Phage-resistant bacterial strains evolved in biofilm models and showed decreased susceptibility to the phages used. Further studies are needed to understand the complexity of phage resistance and the interaction of phages and antibiotics. Our results indicate that the combination of phages, antibiotics, and surgical intervention can have great potential in treating LVAD-associated infections. More than 21 months post-treatment, our patient remains cured of the infection.

Racial disparity exists in the utilization and post-transplant survival benefit of ventricular assist device support in children

PURPOSE

Children of minority race and ethnicity experience inferior outcomes postheart transplantation (HTx). Studies have associated ventricular assist device (VAD) bridge-to-transplant (BTT) with similar-to-superior post-transplant-survival (PTS) compared to no mechanical circulatory support. It is unclear whether racial and ethnic discrepancies exist in VAD utilization and outcomes.

METHODS

The United Network for Organ Sharing (UNOS) database was used to identify 6,121 children (<18 years) listed for HTx between 2006 and 2021: black (B-22% of cohort), Hispanic (H-21%), and white (W-57%). VAD utilization, outcomes, and PTS were compared between race/ethnicity groups. Multivariable Cox proportional analyses were used to study the association of race and ethnicity on PTS with VAD BTT, using backward selection for covariates.

RESULTS

Black children were most ill at listing, with greater proportions of UNOS status 1A/1 (p < 0.001 vs H & W), severe functional limitation (p < 0.001 vs H & W), and greater inotrope requirements (p < 0.05 vs H). Non-white children had higher proportions of public insurance. VAD utilization at listing was: B-11%, H-8%, W-8% (p = 0.001 for B vs H & W). VAD at transplant was: B-24%, H-21%, W-19% (p = 0.001 for B vs H). At transplant, all VAD patients had comparable clinical status (functional limitation, renal/hepatic dysfunction, inotropes, mechanical ventilation; all p > 0.05 between groups). Following VAD, hospital outcomes and one-year PTS were equivalent but long-term PTS was significantly worse among non-whites-(p < 0.01 for W vs B & H). On multivariable analysis, black race independently predicted mortality (hazard ratio 1.67 [95% confidence interval 1.22-2.28]) while white race was protective (0.54 [0.40-0.74]).

CONCLUSIONS

Pediatric VAD use is, seemingly, equitable; the most ill patients receive the most VADs. Despite similar pretransplant and early post-transplant benefits, non-white children experience inferior overall PTS after VAD BTT.