The Society of Thoracic Surgeons Intermacs 2022 Annual Report: Focus on the 2018 Heart Transplant Allocation System

Comparison of waitlist and post-transplant outcomes in patients supported with total artificial heart versus continuous biventricular assist devices

BACKGROUND

Durable biventricular support may be necessary to bridge patients with end-stage biventricular failure to heart transplantation. This study compares waitlist and post-transplant outcomes between patients supported with continuous flow, durable biventricular assist devices (BiVAD), and total artificial heart (TAH).

METHODS

Using the UNOS registry, we analyzed adult (≥18 years old), first-time transplant candidates with TAH or BiVAD at the time of listing or transplantation from 10/1/2010-10/31/2020, with follow-up through 3/31/2022. Multivariable proportional subdistribution hazards models and cause-specific Cox proportional hazards models were used to compare death/deterioration or heart transplantation on the waitlist between cohorts. Kaplan-Meier and multivariable Cox proportional hazards model were used to evaluate one-year post-transplant survival and evaluate difference in outcomes based on annual transplant center volume.

RESULTS

The waitlist cohort included a total of 228 patients (25% BiVAD). Waitlist outcomes between device types were similar. The transplanted cohort included a total of 352 patients (25% BiVAD). There was a trend towards worse one-year post-transplant survival in patients bridged with TAH versus BiVAD (log-rank p-value = 0.072) that persisted after adjusting for age, gender, policy, and removing dual-organ recipients (HR 1.94 (0.94, 3.98) p-value = 0.07). There was a difference in one-year post-transplant survival amongst TAH-bridged patients when stratified by annual transplant center volume (log-rank p-value = 0.013). One-year post-transplant survival between TAH-supported patients from high annual transplant volume centers and BiVAD-supported patients was similar (p-value = 0.815).

CONCLUSIONS

BiVAD and TAH are reasonable support strategies with TAH implantation at high-volume transplant centers (51+ transplants/year) having similar 1-year post-transplant survival to BiVAD-supported patients.

Outcomes after SynCardia® temporary total artificial heart implantation: A 20-year single-center experience in 196 patients

BACKGROUND

The SynCardia® temporary total artificial heart (TAH) serves as a mechanical circulatory support device for patients suffering from irreversible biventricular failure.

METHODS

This retrospective study analyzed 196 consecutive patients who underwent TAH implantation at our center from 2001 to 2021. We assessed survival rates and all-cause mortality during TAH support, including survival post-heart transplantation.

RESULTS

The median age of patients was 55 years, with 88% being male. The primary diagnoses included cardiomyopathy (43.9%), acute myocardial infarction (26.5%), and postcardiotomy heart failure (15.5%). At implantation, 87.2% of patients were classified as INTERMACS Profile 1. The median duration of support was 96 days (IQR: 23-227). Survival rates at 1, 6, and 12 months were 72%, 41%, and 34%, respectively. Postoperative rethoracotomy was necessary in 44.4% of patients; 39.3% experienced neurological events and 24.6% developed gastrointestinal bleeding. Overall, 64.8% of patients died while on support, primarily due to multiple organ failure (55.9%). Factors such as older age, higher bilirubin levels, postcardiotomy and specific underlying diagnoses were independent predictors of mortality during TAH support. On a positive note, 35.2% of patients underwent successful heart transplants, with 1-, 5-, and 10-year posttransplant survival rates of 65%, 58%, and 51%, respectively.

CONCLUSIONS

While high mortality rates persist among patients with biventricular failure, the SynCardia® TAH offers a viable interim solution for critically ill patients, particularly those who can be successfully bridged to heart transplantation.

Data presentation in industry-sponsored cardiac device trials

Industry's influence on clinical trials is well known and extends to various aspects beyond funding, including industry-affiliated authors and industry-affiliated analysts. An area of potential concern is presentation of analyzed data that does not appear favorable to the desired study outcome. Such important data are at times not accorded prominence in discussion. The present article analyses such concerns in data presentation in the landmark trials of two cardiac devices the use of which has increased markedly in recent years (DanGer Shock trial and COAPT trial). It is seen that important data that did not appear favorable to the intended study outcome were relegated mostly to Supplement Section, where they are likely to receive less attention, with little discussion allocated in the text.

Time-varying analyses of survival and outcomes in patients with HeartMate 3 left ventricular assist devices

AIMS

As patients experience longer survival on HeartMate 3 left ventricular assist devices, there is a need to characterize long-term risks of adverse outcomes more precisely. This study characterized temporal variations in risks of mortality and adverse outcomes in patients with a HeartMate 3.

METHODS AND RESULTS

From October 2015 to January 2023, 431 HeartMate 3 devices were implanted at Cleveland Clinic. Survival was estimated to 5 years post-implant. Time-varying risks of death, neurological events, gastrointestinal bleeding, device-related infections, and other adverse events were characterized using multiphase hazard modelling. Survival on HeartMate 3 at 1 and 5 years was 88% and 58%, respectively. Risk of death peaked in the first postoperative month before declining rapidly to a constant, lower hazard. Cumulative number of neurological events/patient at 1 year and 5 years was 0.13 and 0.29, respectively; risk was highest within the first postoperative week, then rapidly declined by 1 month. Cumulative number of gastrointestinal bleeding events/patient at 1 year and 5 years was 0.32 and 0.78, respectively; risk was highest within 1 week postoperatively and gradually declined to a constant risk over the first year. Device-related infections developed in 136 patients. One- and 5-year freedom from device-related infection was 77% and 45%, respectively; risk was initially low before peaking at 6 months postoperatively and then gradually declining to a steady hazard.

CONCLUSION

Long-term survival on HeartMate 3 support was favourable in a large single-centre cohort. Strategies to reduce early postoperative risk of neurological events and late risks of gastrointestinal bleeding, infections and other adverse events are needed.

Improving the Prioritization of Heart Transplantation Candidates for Optimal Clinical Outcomes: A Narrative Review

PURPOSE OF REVIEW

This narrative review evaluates the limitations of current heart transplantation allocation models, which prioritize medical urgency and waitlist time but fail to adequately predict long-term post-transplant outcomes. It aims to identify advanced metrics that can strengthen the prioritization framework while addressing persistent racial, geographic, and socioeconomic inequities in access to transplantation.

RECENT FINDINGS

Recent research indicates that incorporating frailty, nutritional status, immunological compatibility, and pulmonary hemodynamics into allocation frameworks can enhance the prediction of transplant outcomes. The growing use of mechanical circulatory support (MCS) as a bridge to transplantation provides stabilization for critically ill patients; however, disparities in access persist. Studies continue to emphasize the barriers faced by minority and pediatric populations, highlighting the need for expanded donor networks and improved matching criteria. This review highlights the necessity of shifting transplantation prioritization toward multidimensional candidate evaluations that consider both clinical complexity and long-term outcomes. Policy reforms aimed at addressing healthcare disparities and optimizing donor utilization are crucial for improving patient outcomes. Future research should focus on assessing the effectiveness of advanced allocation models, such as continuous distribution frameworks, to promote equitable and sustainable transplantation systems.

Clinical Outcomes of Cardiac Transplantation in Heart Failure Patients with Previous Mechanical Cardiocirculatory Support

Objectives: Heart failure (HF) remains a significant public health issue, with heart transplantation (HT) being the gold standard treatment for end-stage HF. The increasing use of mechanical circulatory support, particularly left ventricular assist devices (LVADs), as a bridge to transplant (BTT), presents new perspectives for increasingly complex clinical scenarios. This study aimed to compare long-term clinical outcomes in patients in heart failure with reduced ejection fraction (HFrEF) receiving an LVAD as BTT to those undergoing direct-to-transplant (DTT) without mechanical support, focusing on survival and post-transplant complications. Methods: A retrospective, single-center study included 105 patients who underwent HT from 2010. Patients were divided into two groups: BTT (n = 28) and DTT (n = 77). Primary endpoints included overall survival at 1 and 7 years post-HT. Secondary outcomes involved late complications, including organ rejection, renal failure, cardiac allograft vasculopathy (CAV), and cerebrovascular events. Results: At HT, the use of LVADs results in longer cardiopulmonary bypass and cross-clamping times in the BTT group; nevertheless, surgical complexity does not affect 30-day mortality. Survival at 1 year was 89.3% for BTT and 85.7% for DTT (p = 0.745), while at 7 years, it was 80.8% and 77.1%, respectively (p = 0.840). No significant differences were observed in the incidence of major complications, including permanent dialysis, organ rejection, and CAV. However, a higher incidence of cerebrovascular events was noted in the BTT group (10.7% vs. 2.6%). Conclusions: LVAD use as BTT does not negatively impact early post-transplant survival compared to DTT. At long-term follow-up, clinical outcomes remained similar across groups, supporting LVADs as a viable option for bridging patients to transplant.

Blood Volume Analysis of Total Artificial Heart Recipients: A Case Series

Blood volume analysis provides a quantitative volume assessment in patients with equivocal or discordant clinical findings. Reports on its use in mechanical circulatory support are limited and it has never been described in patients with a total artificial heart. Our series demonstrates that patients supported with total artificial heart as a bridge to transplant have significant reductions in red blood cell volume and heterogeneous adaptations in their total blood volume and plasma volume. Pathologic derangements in our patient's total blood volume were targeted to restore euvolemia.

The Society of Thoracic Surgeons Intermacs 2024 Annual Report: Focus on Outcomes in Younger Patients

The 15th Annual Report from The Society of Thoracic Surgeons Interagency Registry for Mechanically Assisted Circulatory Support includes 29,634 continuous-flow left ventricular assist devices from the 10-year period between 2014 and 2024. The outcomes reported here demonstrate continued improved survival in the current era of fully magnetically levitated devices, with a significantly higher 1-year (85.7% vs 78.4%) and 5-year (59.7% vs 43.7%) survival than those receiving non-magnetically levitated devices. Magnetically levitated device recipients are experiencing a lower incidence of adverse events, including freedom from gastrointestinal bleeding (72.6%), device malfunction (82.9%), and stroke (86.7%) at 5 years. Additionally, a focus on a subgroup of patients younger than 50 years of age has demonstrated both superior outcomes in survival (91.6% survival at 1 year and 72.6% survival at 5 years) and decreased incidence of adverse events compared with older recipients. This younger cohort also demonstrated more tolerance to the characteristics of sex, race, ethnicity, and psychosocial indicators that are associated with worse outcomes after heart transplantation. Based upon these data, a potential net prolongation of life may be realized by considering prolonged left ventricular assist device support prior to heart transplantation in this population. These analyses provide preliminary data that could positively influence adoption of left ventricular assist device technology in groups previously not seen as candidates for this therapy, while providing a more responsible donor allocation strategy for advanced heart failure patients.

Development and validation of a questionnaire on bodily experience in VAD patients (BE-S)

BACKGROUND

Little is known about the disturbance in bodily experience (BE) following ventricular assist device (VAD) implantation. The level of disturbance in BE serves as an indicator of the status of the patients' adaptation process to the device. This process encompasses coping with both the more affective, psychological conflicts and the more cognitive, practical challenges of living with the VAD. To provide an economical screening tool for everyday clinical practice, we refined and validated a questionnaire on BE in VAD patients.

METHODS

Seven specific items were derived from clinical experience and presented to 365 VAD patients (85% male; time since implantation: 3-36 months). The item structure was examined using factor analyses and probabilistic test theory. Discriminant validity and change sensitivity were determined in relation to associated psychometric instruments.

RESULTS

Four items were found to constitute the unidimensional bodily experience scale (BE-S). Besides a high internal consistency of the scale (ω = 0.86), the RMSEA of >0.01 indicates a very good model fit. The BE-S has high convergent validity with related constructs (Hospital Anxiety and Depression Scale, Kansas City Cardiomyopathy Questionnaire). Change sensitivity analyses proved the BE-S alone to be significantly sensitive to the temporal dynamics of psychological adaptation processes following VAD implantation.

CONCLUSION

The BE-S constitutes a valid and economical tool for clinical practice to assess patients' disturbance in BE after VAD implantation. It is a valuable tool for identifying patients with difficulties in adapting to the VAD. Subsequently, it enables early and focused therapeutic support for these patients at risk.

Cardiac replacement therapy: Critical issues and future perspectives of heart transplantation and artificial heart

Diagnostic and therapeutic advances in the cardiovascular field have caused a progressive reduction in mortality from acute causes, with an ever-increasing chronicity of cardiovascular pathologies. In recent years, mechanical supports have played a fundamental role, allowing the patient to be stabilized in the most critical phase of acute heart failure (AHF) and acting as a "bridge" for definitive therapies. Heart transplantation (HTx) is the gold-standard treatment for end-stage HF, but it is burdened by a series of critical issues that limit its use, first of all the shortage of grafts. It also requires the patient to take immunosuppressive therapy for life, which exposes him to a greater risk of infectious and oncological diseases. For these reasons, in the last years, mechanical supports are increasingly used as "destination therapy", alternatively to HTx. However, also mechanical supports are not free from critical issues that limit their use. In this review we aim to analyze critical issues and future perspectives of advanced HF therapies.

The burden of left ventricular assist device (LVAD) infections on costs, lengths of stay, antimicrobial consumption and resistance: a prospective case control approach

BACKGROUND

Congestive heart failure has reached pandemic levels, and left-ventricular assist devices (LVAD) are increasingly used to treat refractory heart failure. Infection is a leading complication of LVADs. Despite numerous reports (most being retrospective), several knowledge gaps pertaining to the epidemiology and burden of an LVAD-associated infection (LVADi) remain. We sought to address these gaps using a prospective, case-control design.

METHODS

All patients who received an LVAD from November 1, 2018 to August 31, 2023 (n = 110) were included and prospectively monitored until death. Data were extracted from clinical encounters and medical records in real-time or near real-time and imported to Excel and REDcap electronic data capture tools. An LVADi was ascertained using definitions from the mechanical circulatory support academic research consortium in conjunction with and the U.S. National Health Safety Network. All meeting those definitions were included as 'cases.' Patients with no LVADi were controls. Excess lengths-of-stays (LOS) and direct costs were calculated from billing records using a commercial cost accounting software platform (Strata®, Chicago, IL).

RESULTS

The amount of healthcare contact before implantation and discharge to a rehabilitation or skilled nursing facility instead of home were the primary risks for infection, resulting in mean excesses of 25 hospital and 60 antibiotic-days and $43,000 per event. One-third occurred > 1 year after implantation. 35% developed > 1 infection. Gram-negative, fungal, and antimicrobial-resistant organisms predominated deep or repeat infections. 7.2% developed ≥ 3 infections. Organisms became increasingly antimicrobial resistant with subsequent infections, leading to extensive or pan-drug resistance in 4.5% of patients. The burden of an LVADi was 1862 excess hospital days, 3960 excess antibiotic days, and $3.4 million.

CONCLUSIONS

Patients with LVADis had significant increases in costs, LOS, readmissions, and antibiotic usage. Antimicrobial resistance varied directly with the number of repeat infections and antibiotic exposure. Identification of factors associated with LVADi, and quantification of the burden of LVADi can inform prevention efforts and lead to reduced infection rates. As preventing infections in the first place is also important for limiting the emergence of antimicrobial resistance, we offer strategies to avoid LVADis.

TRIAL REGISTRY

Not applicable.

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.

Durable left ventricular assist devices: a contemporary review of their benefits and drawbacks

INTRODUCTION

Heart transplantation, the gold standard for end-stage cardiomyopathy, is hindered by donor shortages and clinical deterioration. Left ventricular assist devices (LVADs) have emerged as crucial alternatives, stabilizing hemodynamics, reversing end-organ damage, and enabling patient discharge. Significant engineering advancements and iterative improvements have since produced devices capable of rivaling heart transplantation in early survival potential. This review serves to provide an overview of LVAD technology, an understanding of current device limitations, and preview new technologies being developed to address them.

AREAS COVERED

This manuscript reviews the evolution of LVAD technology, discussing its benefits, drawbacks, and contemporary outcomes. It will detail the progression, current state, and future directions of LVAD technology, emphasizing its pivotal role in managing advanced heart failure.

EXPERT OPINION

The modern day LVAD has significantly extended the lifespan of patients with end-stage heart failure. However, adverse events remain abound and will be the focus of the next generation of devices. A burgeoning pipline of new technologies abound and preview the possibilities of a sustainable solution to a devastating disease.

Normalcy Among Individuals Living With Long-Term Mechanical Circulatory Support: A Reflexive Thematic Analysis

AIM

To explore descriptions of normalcy among individuals who have lived with mechanical circulatory support for a long time.

DESIGN

Reflexive thematic analysis was used for this qualitative research.

METHODS

A parent study, utilising constructivist grounded theory, was conducted to explore the experiences of advance care planning among mechanical circulatory support individuals. Participants spontaneously shared their experiences of normalcy, which was outside the scope of the primary study. Thus, a secondary analysis using reflexive thematic analysis was performed to explore experiences of normalcy among individuals living with mechanical circulatory support for long-term use.

RESULTS

Twelve transcripts were purposively sampled and analysed. Three major themes were derived from the data: acquiescence, adapting to the device and restructuring family roles.

CONCLUSION

Normalcy continued to evolve years after device implantation because individuals were not prepared to face ongoing psychosocial challenges. Clinicians and researchers must address the complex emotional and social needs related to changes in goal therapy and unanticipated transplant delays. This includes the development of support groups that are aligned with the various stages of the MCS trajectory.

IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE

Clinicians need to engage patients in conversations about disruptions to their perceived 'normal' lifestyle and how they plan to adapt to complex changes. Future support groups can be organised according to individuals' duration of implantation and goal therapy to reduce social withdrawal. Additionally, clinicians should assess bridge to transplant individuals' attitudes before connecting them with transplanted volunteers. Finally, clinicians can support resilience by recognising and discussing the ongoing work required to adapt to the complex changes throughout the mechanical circulatory support trajectory.

IMPACT

Perceptions of normalcy among mechanical circulatory support individuals are subject to ongoing change. Findings will inform clinicians of the social, emotional and familial challenges that require ongoing support and resources for long-term mechanical circulatory support individuals.

REPORTING METHOD

Reporting adhered to the COREQ checklist.

PATIENT CONTRIBUTION

Participants contributed to this study by sharing their experiences of normalcy after living with mechanical circulatory support for 2 years or more.

Association between caseload volume and outcomes in left ventricular assist device implantations - a EUROMACS analysis

AIMS

This EUROMACS study was conducted with the primary aim of investigating the association between a centre's annual caseload and postoperative outcomes among patients undergoing left ventricular assist device (LVAD) implantation.

METHODS AND RESULTS

A total of 4802 patients identified between 2011 and 2020 from 35 participating centres were dichotomized based on the annual caseload of the treating centre at the time of device implant (≤30 vs. >30 LVAD implantations/year). The primary endpoint was 1-year survival. Secondary outcomes included overall survival analysis, device-related adverse events and readmissions. Cumulative follow-up was 10 003 patient-years, with a median follow-up of 1.54 years (interquartile range 0.52-3.15). Patients from higher volume centres more frequently presented in INTERMACS levels 1 and 2, suffered from right heart dysfunction and needed inotropic support. No difference was observed in adjusted 1-year survival. Adjusted overall survival probability was lower in higher volume centres (p = 0.002). In the subgroup analysis of HeartMate 3 devices only, higher volume centres were associated with decreased odds of 1-year survival (adjusted odds ratio 0.43, 95% confidence interval 0.20-0.97, p = 0.041). Similar findings were observed in the cumulative (i.e. learning curve) caseload analyses.

CONCLUSION

In patients undergoing LVAD implantation, centre volume was not associated with 1-year survival, but was related to device-related adverse events. Patient profiles differed with respect to centre size. These findings underscore the necessity for ongoing quality improvement initiatives in all centres, regardless of their annual caseload. Efforts are needed to standardize patient selection and preconditioning to further improve patient outcome.

Ventricular assist device using a thoracotomy-based implant technique: Multi-Center Implantation of the HeartMate 3 in Subjects With Heart Failure Using Surgical Techniques Other Than Full Median Sternotomy (HM3 SWIFT)

OBJECTIVES

The HeartMate 3 (Abbott) left ventricular assist device provides substantial improvement in long-term morbidity and mortality in patients with advanced heart failure. The Implantation of the HeartMate 3 in Subjects With Heart Failure Using Surgical Techniques Other Than Full Median Sternotomy study compares thoracotomy-based implantation clinical outcomes with standard median sternotomy.

METHODS

We conducted a prospective, multicenter, single-arm study in patients eligible for HeartMate 3 implantation with thoracotomy-based surgical technique (bilateral thoracotomy or partial upper sternotomy with left thoracotomy). The composite primary end point was survival free of disabling stroke (modified Rankin score >3), or reoperation to remove or replace a malfunctioning device, or conversion to median sternotomy at 6-months postimplant (elective transplants were treated as a success). The primary end point (noninferiority, -15% margin) was assessed with >90% power compared with a propensity score-matched cohort (ratio 1:2) derived from the Multi-Center Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3 continued access protocol.

RESULTS

The study enrolled 102 patients between December 2020 and July 2022 in the thoracotomy-based arm at 23 North American centers. Follow-up concluded in December 2022. In the Implantation of the HeartMate 3 in Subjects With Heart Failure Using Surgical Techniques Other Than Full Median Sternotomy study group, noninferiority criteria was met (absolute between-group difference, -1.2%; Farrington Manning lower 1-sided 95% CI, -9.3%; P < .0025) and event-free survival was not different (85.0% vs 86.2%; hazard ratio, 1.01; 95% CI, 0.58-2.10). Length of stay with thoracotomy-based implant was longer (median, 20 vs 17 days; P = .03). No differences were observed for blood product utilization, adverse events (including right heart failure), functional status, and quality of life between cohorts.

CONCLUSIONS

Thoracotomy-based implantation of the HeartMate 3 left ventricular assist device is noninferior to implantation via standard full sternotomy. This study supports thoracotomy-based implantation as an additional standard for surgical implantation of the HeartMate 3 left ventricular assist device.

Impact of Heart Transplant Allocation Change on Waitlist Mortality and Posttransplant Mortality in Patients With Left Ventricular Assist Devices

BACKGROUND

In October 2018, the US heart transplant (HT) allocation system was revised giving patients with left ventricular assist device (LVAD) intermediate priority status. Few studies have examined the impact of this policy change on outcomes among patients with LVAD. We sought to determine how the allocation change impacted waitlist and posttransplant mortality in patients with LVAD.

METHODS

We retrospectively assessed the United Network for Organ Sharing registry for patients with LVAD who were listed for or underwent HT between October 2016 and October 2021. We evaluated waitlist mortality using competing risks analysis and a multivariable Fine-Gray model, and posttransplant mortality using Kaplan-Meier survival analysis and a multivariate proportional hazards model.

RESULTS

We analyzed data from 3835 patients with LVAD listed for HT and 3486 patients with LVAD who underwent HT during the study period. Listing for HT preallocation change was significantly associated with an increased risk of waitlist mortality (Gray P=0.0058) compared with postallocation change. After adjustment for covariates, mortality differences by listing era were attenuated, but LVAD brand was significantly associated with waitlist mortality (HM3 versus HMII; hazard ratio, 0.38 [95% CI, 0.21-0.69]; P=0.002; HVAD versus HMII; hazard ratio, 0.79 [95% CI, 0.48-1.30]; P=0.36; overall P=0.004). In contrast, HT postallocation change was associated with increased posttransplant mortality (log-rank P=0.0172) compared with preallocation change. In a multivariable analysis, the association with posttransplant mortality between transplant eras was attenuated, but ischemic time (hazard ratio, 1.16 [95% CI, 1.07-1.26]; P<0.001) and status at time of HT (Status 1-3 versus 4; hazard ratio, 1.29 [95% CI, 1.04-1.61]; P=0.02) were significantly associated with posttransplant mortality.

CONCLUSIONS

Among patients with LVAD, lower waitlist mortality postallocation change was likely driven by improved LVAD technology. Higher posttransplant mortality following the allocation change was largely attributable to longer ischemic times and patient acuity.

[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.

Optimizing Triage of Ambulatory Patients With Advanced Heart Failure: 2-Year Outcomes From REVIVAL

BACKGROUND

Left ventricular assist device (LVAD) use remains uncommon in advanced heart failure (HF) patients not dependent on inotropes.

OBJECTIVES

Before considering a randomized trial comparing a strategy of earlier use of LVAD to continued medical therapy, a better understanding is needed of the clinical trajectory of ambulatory patients with advanced systolic HF on optimal guideline-directed medical therapy (GDMT).

METHODS

REVIVAL enrolled 400 patients with advanced ambulatory systolic HF, ≥1 HF mortality risk marker (≥2 HF hospitalizations past year; or HF hospitalization and high natriuretic peptide; or no HF hospitalizations but low peak oxygen consumption, 6-minute walk, serum sodium, HF survival score or Seattle HF model predicted survival), and no LVAD contraindication at 21 LVAD centers from July 2015 to June 2016. Patients were followed for 2 years or until a primary outcome (death, durable ventricular assist device, or urgent transplant). Clinical outcomes and health-related quality of life were evaluated.

RESULTS

Mean baseline left ventricular ejection fraction was 21%, median 6-minute walk was 341 m, and 92% were Interagency Registry for Mechanically Assisted Circulatory Support profiles 5 to 7. Adherence to GDMT and electrical device therapies was robust. Composite primary outcome occurred in 22% and 37% at 1 and 2 years, with death alone in 8% and 16%, respectively. Patients surviving for 2 years maintained GDMT intensity and had no decline in health-related quality of life.

CONCLUSIONS

Structured, serial follow-up at programs with expertise in caring for advanced ambulatory systolic HF patients facilitates triage for advanced therapies. Better strategies are still needed to avoid deaths in a small but significant group of patients who die without advanced therapies. REVIVAL patients not selected for VAD or transplant have robust survival and patient-reported outcomes, which challenges advocacy for earlier VAD implantation. (Registry Evaluation of Vital Information for VADs in Ambulatory Life [REVIVAL]; NCT01369407).

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.

Influence of implant strategy on the transition from temporary left ventricular assist device to durable mechanical circulatory support

OBJECTIVES

Bridging from a temporary microaxial left ventricular assist device (tLVAD) to a durable left ventricular assist device (dLVAD) is playing an increasing role in the treatment of terminally ill patients with heart failure. Scant data exist about the best implant strategy. The goal of this study was to analyse differences in the dLVAD implant technique and effects on patient outcomes.

METHODS

Data from 341 patients (19 European centres) who underwent a bridge-to-bridge implant from tLVAD to dLVAD between January 2017 and October 2022 were retrospectively analysed. The outcomes of the different implant techniques with the patient on cardiopulmonary bypass, extracorporeal life support or tLVAD were compared.

RESULTS

A durable LVAD implant was performed employing cardiopulmonary bypass in 70% of cases (n = 238, group 1), extracorporeal life support in 11% (n = 38, group 2) and tLVAD in 19% (n = 65, group 3). Baseline characteristics showed no significant differences in age (P = 0.140), body mass index (P = 0.388), creatinine level (P = 0.659), the Model for End-Stage Liver Disease (MELD) score (P = 0.190) and rate of dialysis (P = 0.110). Group 3 had significantly fewer patients with preoperatively invasive ventilation and cardiopulmonary resuscitation before the tLVAD was implanted (P = 0.009 and P < 0.001 respectively). Concomitant procedures were performed more often in groups 1 and 2 compared to group 3 (24%, 37% and 5%, respectively, P < 0.001). The 30-day mortality data showed significantly better survival after an inverse probability of treatment weighting in group 3, but the 1-year mortality showed no significant differences among the groups (P = 0.012 and 0.581, respectively). Postoperative complications like the rate of right ventricular assist device (RVAD) implants or re-thoracotomy due to bleeding, postoperative respiratory failure and renal replacement therapy showed no significant differences among the groups. Freedom from the first adverse event like stroke, driveline infection or pump thrombosis during follow-up was not significantly different among the groups. Postoperative blood transfusions within 24 h were significantly higher in groups 1 and 2 compared to surgery on tLVAD support (P < 0.001 and P = 0.003, respectively).

CONCLUSIONS

In our analysis, the transition from tLVAD to dLVAD without further circulatory support did not show a difference in postoperative long-term survival, but a better 30-day survival was reported. The implant using only tLVAD showed a reduction in postoperative transfusion rates, without increasing the risk of postoperative stroke or pump thrombosis. In this small cohort study, our data support the hypothesis that a dLVAD implant on a tLVAD is a safe and feasible technique in selected patients.

Turbulent flow field in maglev centrifugal blood pumps of CH-VAD and HeartMate III: secondary flow and its effects on pump performance

Secondary flow path is one of the crucial aspects during the design of centrifugal blood pumps. Small clearance size increases stress level and blood damage, while large clearance size can improve blood washout and reduce stress level. Nonetheless, large clearance also leads to strong secondary flows, causing further blood damage. Maglev blood pumps rely on magnetic force to achieve rotor suspension and allow more design freedom of clearance size. This study aims to characterize turbulent flow field and secondary flow as well as its effects on the primary flow and pump performance, in two representative commercial maglev blood pumps of CH-VAD and HeartMate III, which feature distinct designs of secondary flow path. The narrow and long secondary flow path of CH-VAD resulted in low secondary flow rates and low disturbance to the primary flow. The flow loss and blood damage potential of the CH-VAD mainly occurred at the secondary flow path, as well as the blade clearances. By contrast, the wide clearances in HeartMate III induced significant disturbance to the primary flow, resulting in large incidence angle, strong secondary flows and high flow loss. At higher flow rates, the incidence angle was even larger, causing larger separation, leading to a significant decrease of efficiency and steeper performance curve compared with CH-VAD. This study shows that maglev bearings do not guarantee good blood compatibility, and more attention should be paid to the influence of secondary flows on pump performance when designing centrifugal blood pumps.

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.

Stroke outcomes following durable left ventricular assist device implant in patients bridged with micro-axial flow pump: Insights from a large registry

BACKGROUND

Stroke after durable left ventricular assist device (d-LVAD) implantation portends high mortality. The incidence of ischemic and hemorrhagic stroke and the impact on stroke outcomes of temporary mechanical circulatory support (tMCS) management among patients requiring bridge to d-LVAD with micro-axial flow-pump (mAFP, Abiomed) is unsettled.

METHODS

Consecutive patients, who underwent d-LVAD implantation after being bridged with mAFP at 19 institutions, were retrospectively included. The incidence of early ischemic and hemorrhagic stroke after d-LVAD implantation (<60 days) and association of pre-d-LVAD characteristics and peri-procedural management with a specific focus on tMCS strategies were studied.

RESULTS

Among 341 patients, who underwent d-LVAD implantation after mAFP implantation (male gender 83.6%, age 58 [48-65] years, mAFP 5.0/5.5 72.4%), the early ischemic stroke incidence was 10.8% and early hemorrhagic stroke 2.9%. The tMCS characteristics (type of mAFP device and access, support duration, upgrade from intra-aortic balloon pump, ECMELLA, ECMELLA at d-LVAD implantation, hemolysis, and bleeding) were not associated with ischemic stroke after d-LVAD implant. Conversely, the device model (mAFP 2.5/CP vs. mAFP 5.0/5.5: HR 5.6, 95%CI 1.4-22.7, p = 0.015), hemolysis on mAFP support (HR 10.5, 95% CI 1.3-85.3, p = 0.028) and ECMELLA at d-LVAD implantation (HR 5.0, 95% CI 1.4-18.7, p = 0.016) were associated with increased risk of hemorrhagic stroke after d-LVAD implantation. Both early ischemic (HR 2.7, 95% CI 1.9-4.5, p < 0.001) and hemorrhagic (HR 3.43, 95% CI 1.49-7.88, p = 0.004) stroke were associated with increased 1-year mortality.

CONCLUSIONS

Among patients undergoing d-LVAD implantation following mAFP support, tMCS characteristics do not impact ischemic stroke occurrence, while several factors are associated with hemorrhagic stroke suggesting a proactive treatment target to reduce this complication.

Exercise and weight loss with a left ventricular assist device: A case report and review of the literature

With changes in the heart transplant allocation system in the United States, the use of left ventricular device therapy (LVAD) as a bridge to transplant has decreased. Currently, one of the primary reasons to implant a device is for patient support until they can lose weight to qualify for transplant. This paper reviews the outcomes of various weight loss strategies for patients with LVADs including weight reduction surgery and cardiac rehab. Additionally, results of the use of GLP1 agonists on weight loss in general and in heart failure patients is reviewed. Finally, because of the unique issues involving exercise for patients with LVADs, we review safe exercise techniques with instructions for patients.

Understanding Embolus Transport And Source To Destination Mapping Of Thromboemboli In Hemodynamics Driven By Left Ventricular Assist Device

Left Ventricular Assist Devices (LVADs) are a key treatment option for patients with advanced heart failure, but they carry a significant risk of thromboembolic complications. While improved LVAD design, and systemic anticoagulation regimen, have helped mitigate thromboembolic risks, ischemic stroke due to adverse thromboembolic events remains a major concern with current LVAD therapies. Improved understanding of embolic events, and embolus movement to the brain, is critical to develop techniques to minimize risks of occlusive embolic events such as a stroke after LVAD implantation. Here, we address this need, and devise a quantitative in silico framework to characterize thromboembolus transport and distrbution in hemodynamics driven by an operating LVAD. We conduct systematic numerical experiments to quantify the source-to-destination transport patterns of thromboemboli as a function of: LVAD outflow graft anastomosis, LVAD operating pulse modulation, thromboembolus sizes, and origin locations of emboli. Additionally, we demonstrate how the resulting embolus distribution patterns compare and correlate with descriptors based solely on hemodynamic patterns such as helicity, vorticity, and wall shear stress. Using the concepts of size-dependent embolus-hemodynamics interactions, and two jet flow model for hemodynamics under LVAD operation as established in our prior works, we gain valuable insights on departure of thromboembolus distribution from flow distribution, and establish that our in silico model can generate deep insights into embolus dynamics which is not otherwise available from standard of care imaging and clinical data.

Discontinuation of Cardiac Devices at or Near an Adult Patient's End of Life

Advances in medical technology have begun to blur the lines between life and death as well as the lines between appropriate and inappropriate therapy. This review addresses the charged issue of the management of cardiac devices at or near the end of a patient's life, provides a summary of prior and current opinion with some historical context, and attempts to provide some modest guidance as to how to approach the various options to the patient's best advantage. Modalities to be addressed include indwelling electronic devices, the left ventricular assistance device, and extracorporeal mechanical oxygenation, and includes available outcome data as well as ethical analysis from a number of commentators. The expected further increase in technical sophistication of these devices is expected to render the various aspects of device deactivation more and more complex over the course of the next few years such that careful attention to and knowledge about this issue will continue to be more and more necessary.

Current issues of destination therapy in Japan: to achieve 5-year or even longer survival

In April 2021, destination therapy (DT) was finally approved in Japan. Since DT does not aim at heart transplantation (HT), our goal is to have a patient safely remain on an implantable ventricular assist device (VAD) for the rest of his/her life. To achieve this goal, similarly to bridge-to-transplant (BTT) patients, the authors believe the following six aspects are even more crucial in DT patients: (1) to appropriately assess risks before implantation, (2) to carefully determine the ability to manage the device by multidisciplinary discussions, (3) to prevent complications by improving the quality of care, (4) to expand the number of facilities that can take care of DT patients by improving collaboration among the facilities, (5) to reduce the burden of caregivers by utilizing social resources, and (6) to establish a home palliative care system based on advance care planning. In addition, for elderly DT patients to live happy and long lives, it is essential to help them to find a purpose of life and to keep activities of daily living, such as employment, schooling, and participation in social activities, just like the general elderly population. Our goals are not only to do our best for the patients just in front of us, but also to establish a system to follow up our DT cohort, same as BTT one, by all-Japan manner. In the present review, we discuss the current state of DT in Japan and what we need to focus on to maintain or improve its long-term performance.

Three-Year Left Ventricular Assist Device Outcomes and Strategy After Heart Transplant Allocation Score Change

The United Network for Organ Sharing (UNOS) adopted new criteria for the heart allocation score on October 18, 2018 to reflect the changing trends of candidates' mortality while awaiting transplant. We examined the impact of these policy changes on rates of left ventricular assist device (LVAD) implantation and outcomes after transplant from a relatively newer UNOS database. The UNOS registry was used to identify first-time adult heart recipients with LVAD at listing or transplant who underwent transplantation between January 1, 2016 and March 10, 2020. Survival data were collected through March 30, 2023. Those listed before October 18, 2018 but transplanted after were excluded. Patients were divided into before or after change groups. Demographics and clinical parameters were compared. Survival was analyzed with Kaplan-Meier curves and log-rank tests. A p <0.05 was considered significant. We identified 4,387 heart recipients with LVAD in the before (n = 3,606) and after (n = 781) score change eras. The after group had a lower rate of LVAD implantation while listed than the before group (20.4% vs 34.9%, p <0.0001), and were more likely to be female (25.1% vs 20.2%, p = 0.002); in both groups, most recipients (62.8%) were white. There was significantly farther distance from the donor hospital to transplant center in the after group (264.4 NM vs 144.2 NM, p <0.0001) and decreased waitlist days (84.9 ± 105.1 vs 369.2 ± 459.5, p <0.0001). Recipients in the after group were more likely to use extracorporeal membrane oxygenation (3.7% vs 0.5%, p <0.0001) and intravenous inotropes (19.1% vs 7.5%, p <0.0001) and receive a Centers for Disease Control and Prevention increased risk donor organ (37.9% vs 30.5%, p <0.0001). Survival at 3 years was comparable between the 2 groups. The allocation score change in 2018 yielded considerable changes in mechanical circulatory support device implantation strategy and outcomes. The rate of LVAD implantation decreased with increased utilization of temporary mechanical circulatory support devices.

Assessment of Temporary Warfarin Reversal in Patients With Left Ventricular Assist Devices: the KVAD Study

BACKGROUND

Patients with left ventricular assist devices (LVADs) require interruption of warfarin for invasive procedures, but parenteral bridging is associated with many complications. Four-factor prothrombin complex concentrate (4F-PCC) can temporarily restore hemostasis in patients undergoing anticoagulation with warfarin.

OBJECTIVES

This pilot study evaluated the strategy of using variable-dose 4F-PCC to immediately and temporarily reverse warfarin before invasive procedures without holding warfarin in patients with LVADs. The duration of effect of 4F-PCC on factor levels and time to reestablish therapeutic anticoagulation post procedure were assessed.

METHODS

Adult patients with LVADs and planned invasive procedures were enrolled from a single center. Warfarin was continued uninterrupted. The 4F-PCC dose administered immediately pre-procedure was based on study protocol. International normalized ratio (INR)- and vitamin K-dependent factor levels were collected before and during the 48 hours after 4F-PCC administration. The use of parenteral bridging, International Society for Thrombosis and Haemostasis major and clinically relevant nonmajor bleeding (CRNMB) and thromboembolic events at 7 and 30 days were collected.

RESULTS

In 21 episodes of 4F-PCC reversal, median baseline INR was 2.7 (IQR 2.2-3.2). The median dosage of 4F-PCC administered was 1794 units (IQR 1536-2130). At 24 and 48 hours post 4F-PCC administration, median INRs were 1.8 (IQR 1.7-2.0) and 2.0 (IQR 1.9-2.4). Two patients required postoperative bridging. One patient experienced major bleeding within 72 hours, and 2 experienced CRNMB within 30 days. There were no thromboembolic events. Baseline and post 4F-PCC vitamin K-dependent factor levels corresponded with changes in INR values. The median time to achieve therapeutic INR post-procedure was 2.5 days (IQR, 1-4).

CONCLUSION

Administration of 4F-PCC for temporary reversal of warfarin for invasive procedures in patients with LVADs allowed for continued warfarin dosing with minimal use of post-intervention bridging, limited bleeding and no thromboembolic events.

Durable left ventricular assist devices as a bridge to transplantation: what to expect along the way?

INTRODUCTION

The scarcity of donors coupled with the improvements in left ventricular assist devices (LVAD) technology has led to the use of LVAD as a bridge to transplantation (BTT).

AREAS COVERED

The authors provide an overview of the current status of LVAD BTT implantation with special focus ranging from patient selection and pre-implantation optimization to post-transplant outcomes.

EXPERT OPINION

The United Network for Organ Sharing 2018 policy amendment resulted in a significant reduction in the number of LVADs used for BTT in the US. To overcome this issue, modifications in the US allocation policy to consider factors such as days on device support, age, and type of complications may be necessary to potentially increase implantation rates.

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.

Therapeutic potential of human induced pluripotent stem cell-derived cardiac tissue in an ischemic model with unloaded condition mimicking left ventricular assist device

OBJECTIVE

This study aimed to explore the therapeutic potential of human induced pluripotent stem cell (hiPSC)-derived cardiac tissues (HiCTs) in the emerging approach of bridge to recovery for severe heart failure with ventricular assist devices. We used a rat model of heterotopic heart transplantation (HTx) to mimic ventricular assist device support and heart unloading.

METHODS

HiCTs were created by inserting gelatin hydrogel microspheres between cell sheets made from hiPSC-derived cardiovascular cells. Male athymic nude rats underwent myocardial infarction (MI) and were divided into the following groups: MI (loaded, untreated control), MI + HTx (unloaded, untreated control), MI + HTx + HiCT (unloaded, treated), and MI + HiCT (loaded, treated). HiCTs were placed on the epicardium of the heart in treated groups. We evaluated HiCT engraftment, fibrosis, and neovascularization using histologic analysis.

RESULTS

After 4 weeks, HiCTs successfully engrafted in 5 of 6 rats in the MI + HTx + HiCT group (83.3%). The engrafted HiCT area was greater under unloaded conditions (MI + HTx + HiCT) than loaded conditions (MI + HiCT) (P < .05). MI + HTx + HiCT had a significantly smaller infarct area compared with MI and MI + HTx. The MI + HTx + MiCT group exhibited greater vascular density in the border zone than MI and MI + HTx. HiCT treatment suppressed cardiomyocyte atrophy due to left ventricular unloading (P = .001). The protein level of muscle-specific RING finger 1, an atrophy-related ubiquitin ligase, was lower in the MI + HTx + HiCT group than in MI + HTx (P = .036).

CONCLUSIONS

Transplanting HiCTs into ischemic hearts under unloaded conditions promoted engraftment, neovascularization, attenuated infarct remodeling, and suppressed myocyte atrophy. These results suggest that HiCT treatment could contribute to future advancements in bridge to recovery.

Evaluation of the Hemocompatibility of the Direct Oral Anticoagulant Apixaban in Left Ventricular Assist Devices: The DOAC LVAD Study

BACKGROUND

Patients receiving left ventricular assist device (LVAD) support require long-term anticoagulation to reduce the risk of thromboembolic complications. Apixaban is a direct oral anticoagulant that has become first-line therapy; however, its safety in LVAD recipients has not been well described.

OBJECTIVES

This study sought to investigate whether, in patients with a fully magnetically levitated LVAD, treatment with apixaban would be feasible and comparable with respect to safety and freedom from the primary composite outcome of death or major hemocompatibility-related adverse events (HRAEs) (stroke, device thrombosis, major bleeding, aortic root thrombus, and arterial non-central nervous system thromboembolism) as compared with treatment with warfarin.

METHODS

The DOAC LVAD (Evaluation of the Hemocompatibility of the Direct Oral Anti-Coagulant Apixaban in Left Ventricular Assist Devices) trial was a phase 2, open label trial of LVAD recipients randomized 1:1 to either apixaban 5 mg twice daily or warfarin therapy. All patients were required to take low-dose aspirin. Patients were followed up for 24 weeks to evaluate the primary composite outcome.

RESULTS

A total of 30 patients were randomized: 14 patients to warfarin and 16 patients to apixaban. The median patient age was 60 years (Q1-Q3: 52-71 years), and 47% were Black patients. The median time from LVAD implantation to randomization was 115 days (Q1-Q3: 56-859 days). At 24 weeks, the primary composite outcome occurred in no patients receiving apixaban and in 2 patients (14%) receiving warfarin (P = 0.12); these 2 patients experienced major bleeding from gastrointestinal sources.

CONCLUSIONS

Anticoagulation with apixaban was feasible in patients with an LVAD without an excess of HRAEs or deaths. This study informs future pivotal clinical trials evaluating the safety and efficacy of apixaban in LVAD recipients. (Evaluation of the Hemocompatibility of the Direct Oral Anti-Coagulant Apixaban in Left Ventricular Assist Devices [DOAC LVAD]; NCT04865978).

Bridge to Transplantation: Policies Impact Practices

Since the development of the first heart allocation system in 1988 to the most recent heart allocation system in 2018, the road to heart transplantation has continued to evolve. Policies were shaped with advances in temporary and durable left ventricular assist devices as well as prioritization of patients based on degree of illness. Herein, we review the changes in the heart allocation system over the past several decades and the impact of practice patterns across the United States.

HeartMate 3 driveline damage by gradual corrosion due to liquid infiltration: a case report

A 31-year-old man with a HeartMate 3 was admitted with a "Driveline Communication Fault" alarm due to liquid infiltration. Eleven months earlier, the connector between the modular and pump cables had gotten wet when he was taking a shower. The cable connector was dried immediately, and no alarm had been observed during follow-up. Subsequently, the modular cable and system controller were replaced, with corrosion found on the modular cable connector. The "Communication Fault" alarm recurred, and complete damage to the communication cables was discovered. The pump was replaced, and the removed pump cable connector showed corrosion as well. If the driveline connector gets wet, the multidisciplinary team should discuss if it should be immediately disconnected and dried, averting the need for future pump replacements due to corrosion.

Gender and Race Differences in HeartMate3 Left Ventricular Assist Device as a Bridge to Transplantation

BACKGROUND

Gender and racial disparities exist after left ventricular assist device (LVAD) implantation. Compared with older devices, the HeartMate 3 (HM3) (Abbott Cardiovascular) has demonstrated improved survival. Whether HM3 differentially improves outcomes by gender or race and ethnic groups is unknown.

OBJECTIVES

The purpose of this study is to examine differences by gender and race in the use of HM3 among patients listed for heart transplantation (HT) and associated waitlist and post-transplant outcomes.

METHODS

The authors examined all patients (20% women, 33% Black) who received LVADs as bridge to transplantation (BTT) between January 2018 and June 2020, in the OPTN (Organ Procurement and Transplantation Network) database. Trends in use of HM3 were evaluated by gender and race. Competing events of death/delisting and transplantation were evaluated using subdistribution hazard models. Post-transplant outcomes were evaluated using multivariate logistic regression adjusted for demographic, clinical, and donor characteristics.

RESULTS

Of 11,524 patients listed for HT during the study period, 955 (8.3%) had HM3 implanted as BTT. Use of HM3 increased for all patients, with no difference in use by gender (P = 0.4) or by race (P = 0.2). Competing risk analysis did not demonstrate differences in transplantation or death/delisting in men compared with women (HT: adjusted HR [aHR]: 0.92 [95% CI: 0.70-1.21]; death/delisting: aHR: 0.91 [95% CI: 0.59-1.42]), although Black patients were transplanted fewer times than White patients (HT: aHR: 0.72 [95% CI: 0.57-0.91], death/delisting: aHR: 1.36 [95% CI: 0.98-1.89]). One-year post-transplant survival was comparable by gender (aHR: 0.52 [95% CI: 0.21-1.70]) and race (aHR: 0.76 [95% CI: 0.34-1.70]), with no differences in rates of stroke, acute rejection, or graft failure.

CONCLUSIONS

Use of HM3 among patients listed for HT has increased over time and by gender and race. Black patients with HM3 were less likely to be transplanted compared with White patients, but there were no differences in post-transplant outcomes between these groups or between men and women.

The safety of sodium glucose transporter 2 inhibitors and trends in clinical and hemodynamic parameters in patients with left ventricular assist devices

BACKGROUND

The safety and impact of sodium glucose transporter 2 inhibitors (SGLT2-I) in patients with left ventricular assist devices (LVAD) are unknown.

METHODS

A retrospective analysis of all consecutive patients who underwent LVAD Heart Mate 3 (HM3) implantation at a single medical center and received SGLT2-I therapy following surgery was conducted. LVAD parameters, medical therapy, laboratory tests, echocardiography, and right heart catheterization (RHC) study results were recorded and compared before and after initiation of SGLT2-I.

RESULTS

SGLT2-I medications were initiated in 29 (21%) of 138 patients following HM3 implantation (23 (79%) received Empagliflozin and 6 (21%) Dapagliflozin). The mean age at the time of LVAD implantation was 62 ± 6.7 years, 25 (86%) were male, and 23 (79%) had diabetes mellitus. The median time from HM3 implantation to SGLT2-I initiation was 108 days, IQR (26-477). Following SGLT2-I therapy, the daily dose of furosemide decreased from 47 to 23.5 mg/day (mean difference = 23.5 mg/d, 95% CI 8.2-38.7, p = 0.004) and significant weight reduction was observed (mean difference 2.5 kg, 95% CI 0.7-4.3, p = 0.008). Moreover, a significant 5.6 mm Hg reduction in systolic pulmonary artery pressure (sPAP) was measured during RHC (95% CI 0.23-11, p = 0.042) in a subgroup of 11 (38%) patients. LVAD parameters were similar before and after SGLT2-I initiation (p > 0.2 for all). No adverse events were recorded during median follow-up of 354 days, IQR (206-786).

CONCLUSION

SGLT2-I treatment is safe in LVAD patients and might contribute to reduction in patients sPAP.

Disturbance in bodily experience following ventricular assist device implantation

BACKGROUND

Disturbance in bodily experience (BE) is a potential adverse consequence of ventricular assist device (VAD) implantation. The concept BE encompasses all cognitive and affective processes related to the subjective experience of one's own body.

METHODS

A cross-sectional, multicenter study was performed, involving 365 VAD patients (85% male; time postimplant: 3-36 months). Patients completed a BE questionnaire (BE-S, 5-point Likert scale), and the disturbance in BE was analyzed based on sex, time since implantation (in the first, second, or third years postimplant), and patient acuity (elective vs emergent implantation). Subsidiary, patients' gratitude was surveyed.

RESULTS

Disturbance in BE was not particularly pronounced (mean = 2.69, standard deviation = 1.17). Eighty-five percent of patients expressed high levels of gratitude. Disturbance in BE decreased (p = 0.04), while gratitude increased (p = 0.02) with time since implantation. Female patients showed more disturbance in BE (p = 0.01) and less gratitude (p = 0.01) compared to male patients. Among patients who underwent emergency implantation, the decrease in disturbance occurred predominantly in the third year, exceeding the level observed in elective implanted patients (p = 0.03).

CONCLUSIONS

Disturbance in BE following VAD implantation does generally not reach excessive levels and tends to decrease over time. Our data indicate more disturbance and less gratitude in female patients. In emergently implanted patients, disturbance in BE is prolonged. Screening for disturbance in BE is recommended during follow-up, especially for these at-risk groups, to ensure early and focused psychological support.

Association between pulmonary artery pulsatility and mortality after implantation of left ventricular assist device

AIMS

Right ventricular failure after left ventricular assist device (LVAD) implantation is a major concern that remains challenging to predict. We sought to investigate the relationship between preoperative pulmonary artery pulsatility index (PAPi) and mortality after LVAD implantation.

METHODS AND RESULTS

A retrospective analysis of the ASSIST-ICD multicentre registry allowed the assessment of PAPi before LVAD according to the formula [(systolic pulmonary artery pressure - diastolic pulmonary artery pressure)/central venous pressure]. The primary endpoint was survival at 3 months, according to the threshold value of PAPi determined by the receiver operating characteristic (ROC) curve. A multivariate analysis including demographic, echographic, haemodynamic, and biological variables was performed to identify predictive factors for 2 year mortality. One hundred seventeen patients were included from 2007 to 2021. The mean age was 58.45 years (±13.16), with 15.4% of women (sex ratio 5.5). A total of 53.4% were implanted as bridge to transplant and 43.1% as destination therapy. Post-operative right ventricular failure was observed in 57 patients (48.7%), with no significant difference between survivors and non-survivors at 1 month (odds ratio 1.59, P = 0.30). The median PAPi for the whole study population was 2.83 [interquartile range 1.63-4.69]. The threshold value of PAPi determined by the ROC curve was 2.84. Patients with PAPi ≥ 2.84 had a higher survival rate at 3 months [PAPi < 2.84: 58.1% [46.3-72.8%] vs. PAPi ≥ 2.84: 89.1% [81.1-97.7%], hazard ratio (HR) 0.08 [0.02-0.28], P < 0.01], with no significant difference after 3 months (HR 0.67 [0.17-2.67], P = 0.57). Other predictors of 2 year mortality were systemic hypertension (HR 4.22 [1.49-11.97], P < 0.01) and diabetes mellitus (HR 4.90 [1.83-13.14], P < 0.01). LVAD implantation as bridge to transplant (HR 0.18 [0.04-0.74], P = 0.02) and heart transplantation (HR 0.02 [0.00-0.18], P < 0.01) were associated with a higher survival rate at 2 years.

CONCLUSIONS

Preoperative PAPi < 2.84 was associated with a higher risk of early mortality after LVAD implantation without impacting 2 year outcomes among survivors.

Multicenter evaluation of left ventricular assist device implantation with or without ECMO bridge in cardiogenic shock

BACKGROUND

The efficacy of extracorporeal membrane oxygenation (ECMO) as a bridge to left ventricular assist device (LVAD) remains unclear, and recipients of the more contemporary HeartMate 3 (HM3) LVAD are not well represented in previous studies. We therefore undertook a multicenter, retrospective study of this population.

METHODS AND RESULTS

INTERMACS 1 LVAD recipients from five U.S. centers were included. In-hospital and one-year outcomes were recorded. The primary outcome was the overall mortality hazard comparing ECMO versus non-ECMO patients by propensity-weighted survival analysis. Secondary outcomes included survival by LVAD type, as well as postoperative and one-year outcomes. One hundred and twenty-seven patients were included; 24 received ECMO as a bridge to LVAD. Mortality was higher in patients bridged with ECMO in the primary analysis (HR 3.22 [95%CI 1.06-9.77], p = 0.039). Right ventricular assist device was more common in the ECMO group (ECMO: 54.2% vs non-ECMO: 11.7%, p < 0.001). Ischemic stroke was higher at one year in the ECMO group (ECMO: 25.0% vs non-ECMO: 4.9%, p = 0.006). Among the study cohort, one-year mortality was lower in HM3 than in HeartMate II (HMII) or HeartWare HVAD (10.5% vs 46.9% vs 31.6%, respectively; p < 0.001) recipients. Pump thrombosis at one year was lower in HM3 than in HMII or HVAD (1.8% vs 16.1% vs 16.2%, respectively; p = 0.026) recipients.

CONCLUSIONS

Higher mortality was observed with ECMO as a bridge to LVAD, likely due to higher acuity illness, yet acceptable one-year survival was seen compared with historical rates. The receipt of the HM3 was associated with improved survival compared with older generation devices.

An ISHLT consensus statement on strategies to prevent and manage hemocompatibility related adverse events in patients with a durable, continuous-flow ventricular assist device

Life expectancy of patients with a durable, continuous-flow left ventricular assist device (CF-LVAD) continues to increase. Despite significant improvements in the delivery of care for patients with these devices, hemocompatability-related adverse events (HRAEs) are still a concern and contribute to significant morbility and mortality when they occur. As such, dissemination of current best evidence and practices is of critical importance. This ISHLT Consensus Statement is a summative assessment of the current literature on prevention and management of HRAEs through optimal management of oral anticoagulant and antiplatelet medications, parenteral anticoagulant medications, management of patients at high risk for HRAEs and those experiencing thrombotic or bleeding events, and device management outside of antithrombotic medications. This document is intended to assist clinicians caring for patients with a CF-LVAD provide the best care possible with respect to prevention and management of these events.

Impact of Cardiac Resynchronization Therapy on Ventricular Arrhythmias and Survival After Durable Left Ventricular Assist Device Implantation

The impact of cardiac resynchronization therapy (CRT) in patients receiving durable left ventricular assist device (LVAD) implantation remains unclear and there is no consensus regarding postoperative management. We sought to determine the impact of postoperative management of CRT on clinical outcomes following LVAD implantation. A total of 789 patients underwent LVAD implantation at our institution from 2007 to 2022 including 195 patients (24.7%) with preoperative CRT. Patients with preoperative CRT were significantly older and more frequently received an LVAD as destination therapy compared to patients without preoperative CRT. After LVAD implantation, 85 patients had CRT programmed "off" and 74 patients had CRT programmed "on." The risk of mortality was significantly increased amongst patients with preoperative CRT that was turned "on" following LVAD implantation compared to patients with preoperative CRT turned "off" following implant (subdistribution hazard ratio [sdHR] = 1.54; 1.06-2.37 95% confidence interval [CI]; p = 0.036). There was no significant difference between incidence of ventricular arrhythmias in patients with and without postoperative CRT "on" (35.1% vs. 48.2%; p = 0.095). Additional clinical trials are warranted to determine the best CRT programming strategy following LVAD implantation.

Impact of Diabetes Mellitus on Outcomes in Patients with Left Ventricular Assist Devices

Heart failure (HF) represents a significant health burden in the United States, resulting in substantial mortality and healthcare costs. Through the array of treatment options available, including lifestyle modifications, medications, and implantable devices, HF management has evolved. Left ventricular assist devices (LVADs) have emerged as a crucial intervention, particularly in patients with advanced HF. However, the prevalence of comorbidities such as diabetes mellitus (DM) complicates treatment outcomes. By elucidating the impact of DM on LVAD outcomes, this review aims to inform clinical practice and enhance patient care strategies for individuals undergoing LVAD therapy. Patients with DM have higher rates of hypertension, dyslipidemia, peripheral vascular disease, and renal dysfunction, posing challenges to LVAD management. The macro/microvascular changes that occur in DM can lead to cardiomyopathy and HF. Glycemic control post LVAD implantation is a critical factor affecting patient outcomes. The recent literature has shown significant decreases in hemoglobin A1c following LVAD implantation, representing a possible bidirectional relationship between DM and LVADs; however, the clinical significance of this decrease is unclear. Furthermore, while some studies show increased short- and long-term mortality in patients with DM after LVAD implantation, there still is no literature consensus regarding either mortality or major adverse outcomes in DM patients.

Impact of prolonged cardiopulmonary resuscitation on outcomes in heart transplantation with higher risk donor heart

OBJECTIVES

To evaluate the influence of prolonged cardiopulmonary resuscitation (CPR) on outcomes in heart transplantation with higher risk donor hearts (HRDHs).

METHODS

Patients transplanted in our hospital between May 2006 and December 2019 were divided into 2 groups, HRDH recipients and non HRDH recipients. HRDH was defined as meeting at least one of the following criteria: (1) donor left ventricular ejection fraction ≤ 50%, (2) donor-recipient predicted heart mass ratio < 0.8 or > 1.2, (3) donor age ≥ 55 years, (4) ischemic time > 4 h and (5) catecholamine index > 20. Recipients of HRDHs were divided into 3 groups according to the time of CPR (Group1: non-CPR, Group 2: less than 30 min-CPR, and Group 3: longer than 30 min CPR).

RESULTS

A total of 125 recipients were enrolled in this study, composing of HRDH recipients (n = 97, 78%) and non HRDH recipients (n = 28, 22%). Overall survival and the rate of freedom from cardiac events at 10 years after heart transplantation were comparable between two groups. Of 97 HRDH recipients, 54 (56%) without CPR, 22 (23%) with CPR < 30 min, and 21 (22%) with CPR ≥ 30 min were identified. One-year survival rates were not significantly different among three groups. The 1-year rate of freedom from cardiac events was not also statistically different, excluding the patients with coronary artery disease found in early postoperative period, which was thought to be donor-transmitted disease. Multivariate logistics regression for cardiac events identified that the CPR duration was not a risk factor even in HRDH-recipients.

CONCLUSION

The CPR duration did not affect the outcomes after heart transplantation in HRDH recipients.

Current status and future directions in pediatric ventricular assist device

A ventricular assist device (VAD) is a form of mechanical circulatory support that uses a mechanical pump to partially or fully take over the function of a failed heart. In recent decades, the VAD has become a crucial option in the treatment of end-stage heart failure in adult patients. However, due to the lack of suitable devices and more complicated patient profiles, this therapeutic approach is still not widely used for pediatric populations. This article reviews the clinically available devices, adverse events, and future directions of design and implementation in pediatric VADs.

The International Society for Heart and Lung Transplantation (ISHLT): 2024 infection definitions for durable and acute mechanical circulatory support devices

Infections remain a significant concern in patients receiving mechanical circulatory support (MCS), encompassing both durable and acute devices. This consensus manuscript provides updated definitions for infections associated with durable MCS devices and new definitions for infections in acute MCS, integrating a comprehensive review of existing literature and collaborative discussions among multidisciplinary specialists. By establishing consensus definitions, we seek to enhance clinical care, facilitate consistent reporting in research studies, and ultimately improve outcomes for patients receiving MCS.