The Society of Thoracic Surgeons Intermacs 2020 Annual Report

Left Ventricular Assist Device Implantation in Cancer-Therapy-Related Heart Failure

Objectives: Cancer-therapy-related heart failure (CTrHF) due to cardiotoxic drugs or radiation is a growing cause of end-stage heart failure. Limited knowledge is available concerning the use of continuous-flow left-ventricular-assist devices (cfLVAD) in this setting. Methods: The files of all 1334 patients who underwent cfLVAD implantation between December 2008 and December 2020 were screened for the cause of heart failure. All patients with CTrHF were included in the analysis. Results: A total of 32 patients with a median age of 58 years (IQR: 46–65) were included in the study; 15 (47%) were male. The median time from the first diagnosis of heart failure (HF) to cfLVAD implantation was 6 months (IQR 2–24), and from cancer treatment to cfLVAD implantation 40 months (IQR 5–144). Malignancies comprised non-Hodgkin lymphoma (n = 12, 37%), breast cancer (n = 9, 28%), sarcoma (n = 5, 16%), leukemia (n = 5, 16%), and others (n = 1, 3%). In 24 patients, chemotherapy included anthracyclines (others n = 2, unknown n = 6). Chest radiation was performed in 13 patients (39%). Moreover, 71% were classified as INTERMACS profile 1 or 2. The 30-day survival rate after LVAD implantation was 88%. Rethoracotomy was necessary in nine (29%), and a temporary right ventricular assist device in seven (21%) patients. The median survival was 29 months. There was no significant difference in survival or right HF between patients with CTrHF and a matched control group. Conclusions: CfLVAD implantation is feasible in high-risk patients with CTrHF with or without prior chest radiation.

Impact of preoperative Impella support on destination left ventricular assist device outcomes

BACKGROUND

Although left ventricular assist device (LVAD) implantation is associated with improved heart failure survival, the impact of pre-implantation Impella support on outcomes is unknown. We undertook this study to evaluate the impact of preoperative Impella support on LVAD outcomes.

METHODS

We conducted a retrospective review of all Heartmate 3 LVAD implants. Primary stratification was by the need for preoperative Impella support with the 5.0/5.5 device. Longitudinal survival was assessed by the Kaplan-Meier method. Multivariable Cox proportional hazards regression models were developed to evaluate mortality. Secondary outcomes included changes in laboratory values during Impella support.

RESULTS

From 2017 to 2021, 87 patients underwent LVAD implantation. Sixteen were supported with a single inotrope, 36 with dual inotropes, 27 with Impella, and 3 with extracorporeal membrane oxygenation (ECMO). When stratified by the need for Impella, there was no difference in survival at 30-days (98.3 [88.2-99.8]% vs. 96.3 [76.5-99.5]%, p = .59), 1-year (91.0 [79.8-96.2] vs. 74.9 [51.7-88.2], p = .10), or at 2 years (87.9 [74.3-94.5] vs. 74.9 [51.7-88.2], p = .15). On multivariable modeling, the need for preoperative Impella was not associated with an increased hazard of 1-year (1.24 [0.23-6.73], p = .81) or 2-year mortality (1.05 [0.21-5.19], p = .95). After 7 (5-10) days of Impella support, recipient creatinine (p < .01), creatinine clearance (p = .02), and total bilirubin (p = .053) improved and lactic acidosis resolved (p < .01).

CONCLUSIONS

Preoperative Impella support is not associated with increased short or long-term mortality but is associated with improved renal and hepatic function as well as total body perfusion before LVAD implantation.

Impact of psoas muscle evaluation on clinical outcomes in patients undergoing left ventricular assist device implantation

AIMS

The measurement of muscle mass reflects the physical components of frailty, which might affect postoperative outcomes in patients undergoing left ventricular assist device (LVAD) implantation. The aim of this study was to investigate the relationship between preoperative skeletal muscle evaluation and clinical outcomes in patients undergoing LVAD implantation.

METHODS

From January 2010 to December 2017, a total of 63 patients were enrolled in this single-centre study. A retrospective analysis of preoperative abdominal computed tomography (CT) for psoas muscle index (PSMI) and Hounsfield-Units of the Psoas Muscle (PSHU) at the level of the mid-L4 vertebra was performed.

RESULTS

Sixty-three patients (male; n = 49, 78%), with a mean age of 58.0 ± 11.8 years, were treated with LVAD due to dilated (32%) or ischemic cardiomyopathy (68%). Among them, 43 patients (68.3%) were categorized in the Interagency Registry for Mechanically Assisted Circulatory Support profile I. The survival rate was 73.0% at 30 days and 44.4% at 1 year. Receiver-operating characteristic (ROC) curve analyses revealed that PSMI was a significant numeric predictor of 1-year mortality (P = 0.04). In contrast, PSHU displayed a significant predictive potential for pericardial effusion (P = 0.03) and respiratory insufficiency (P = 0.01). In addition, comparative ROC curve analysis revealed no significant difference in the predictive potential of PSMI and PSHU.

CONCLUSION

Preoperative PSMI might be a predictor of 1-year mortality in patients undergoing LVAD implantation. In contrast, the PSHU seemed to potentially assume postoperative adverse events in this study. Thus, the evaluation of the preoperative psoas muscle using CT appears to be promising.

Lived experiences of patients implanted with left ventricular assist devices

BACKGROUND

Besides survival, improvement in quality of life (QoL) is a major aim of left ventricular assist device (LVAD) implantation. QoL assessment tools in current use are effective in the gathering of standardized metrics but are limited in their ability to elucidate everyday lived patient experiences that also affect overall patient wellbeing.

OBJECTIVE

To describe and understand the lived experiences of patients undergoing long-term circulatory support with LVAD.

METHODS

A phenomenological approach was used. Purposive sampling of consecutive willing inpatients and outpatients living with an LVAD for longer than 6 months was conducted until theme saturation. There were a total of 21 patients interviewed and this was then recorded and transcribed.

RESULTS

A total of eight themes emerged from the data. Overall, the patients' quality of life was affected by: (1) whether they had experienced improvements or setbacks in their recent health condition, (2) experiencing burdens from their device such as weight and handling, (3) limitations in their physical ability such as participating in sports, their inability to work; or reduced sleep, (4) reduced social interactions; (5) reduction in sexual activity and performance; (6) experiencing emotional and psychological problems and experiencing anxiety. Patients highlighted the value of obtaining (7) support from family and friends. The interviews also revealed that some patients experienced the feeling of (8) optimism and obtaining "a second chance" at life.

CONCLUSIONS

LVAD patients have unique concerns and lived experiences. Some themes emerging from this interview series such as having to give up work, having reduced social contact, reduced sexual activity and emotional problems, family support structures demand careful attention during the pre-implantation counselling and post implantation ongoing care. These aspects also deserve more attention in quality of life studies among LVAD patients. Patients with recent improvements in health reported a more positive outlook. Overall the majority of patients reported feeling that they obtained a second chance at life.

Sex Differences in Left Ventricular Assist Device-related Emergency Department Encounters in the United States

BACKGROUND

There is a paucity of data regarding sex differences in the profiles and outcomes of ambulatory patients on left ventricular assist device (LVAD) support who present to the emergency department (ED).

METHODS AND RESULTS

We performed a retrospective analysis of 57,200 LVAD-related ED patient encounters from the 2010 to 2018 Nationwide Emergency Department Sample. International Classification of Diseases Clinical Modification, Ninth Revision and Tenth Revision, codes identified patients aged 18 years or older with LVADs and associated primary and comorbidity diagnoses. Clinical characteristics and outcomes were stratified by sex and compared. Multivariable logistic regression was used to evaluate predictors of hospital admission and death. Female patient encounters comprised 27.2% of ED visits and occurred at younger ages and more frequently with obesity and depression (all P < .01). There were no sex differences in presentation for device complication, stroke, infection, or heart failure (all P > .05); however, female patient encounters were more often respiratory- and genitourinary or gynecological related (both P < .01). After adjustment for age group, diabetes, depression, and hypertension, male patient encounters had a 38% increased odds of hospital admission (95% confidence interval 1.20-1.58), but there was no sex difference in the adjusted odds of death (odds ratio 1.11, 95% confidence interval 0.86-1.45).

CONCLUSIONS

Patient encounters of females on LVAD support have significantly different comorbidities and outcomes compared with males. Further inquiry into these sex differences is imperative to improve long-term outcomes.

Comprehensive and Safe Decongestion in Acutely Decompensated Heart Failure

PURPOSE OF THE REVIEW

Progressive intravascular, interstitial, and alveolar fluid overload underlies the transition from compensated to acutely decompensated heart failure and loop diuretics are the mainstay of treatment. Adverse effects and resistance to loop diuretics received much attention while the contribution of a depressed cardiac output to diuretic resistance was downplayed.

RECENT FINDINGS

Analysis of experience with positive inotropic agents, especially dobutamine, indicates that enhancement of cardiac output is not consistently associated with increased renal blood flow. However, urinary output and renal sodium excretion increase likely due to dobutamine-mediated decrease in renal and systemic reduced activation of sympathetic nervous- and renin-angiotensin-aldosterone system. Mechanical circulatory support with left ventricular assist devices ascertained the contribution of low cardiac output to diuretic resistance and the pathogenesis and progression of kidney disease in acutely decompensated heart failure. Diuretic resistance commonly occurs in acutely decompensated heart failure. However, failure to resolve fluid overload despite high doses of loop diuretics should alert to the presence of a low cardiac output state.

An approach to quantify parameter uncertainty in early assessment of novel health technologies

Health economic modeling of novel technology at the early stages of a product lifecycle has been used to identify technologies that are likely to be cost-effective. Such early assessments are challenging due to the potentially limited amount of data. Modelers typically conduct uncertainty analyses to evaluate their effect on decision-relevant outcomes. Current approaches, however, are limited in their scope of application and imposes an unverifiable assumption, that is, uncertainty can be precisely represented by a probability distribution. In the absence of reliable data, an approach that uses the fewest number of assumptions is desirable. This study introduces a generalized approach for quantifying parameter uncertainty, that is, probability bound analysis (PBA), that does not require a precise specification of a probability distribution in the context of early-stage health economic modeling. We introduce the concept of a probability box (p-box) as a measure of uncertainty without necessitating a precise probability distribution. We provide formulas for a p-box given data on summary statistics of a parameter. We describe an approach to propagate p-boxes into a model and provide step-by-step guidance on how to implement PBA. We conduct a case and examine the differences between the status-quo and PBA approaches and their potential implications on decision-making.

Association Between Care Fragmentation and Total Spending After Durable Left Ventricular Device Implant: A Mediation Analysis of Health Care-Associated Infections Within a National Medicare-Society of Thoracic Surgeons Intermacs Linked Dataset

BACKGROUND

Care fragmentation is associated with higher rates of infection after durable left ventricular assist device (LVAD) implant. Less is known about the relationship between care fragmentation and total spending, and whether this relationship is mediated by infections.

METHODS

Total payments were captured from admission to 180 days post-discharge. Drawing on network theory, a measure of care fragmentation was developed based on the number of shared patients among providers (ie, anesthesiologists, cardiac surgeons, cardiologists, critical care specialists, nurse practitioners, physician assistants) caring for 4,987 Medicare beneficiaries undergoing LVAD implantation between July 2009 - April 2017. Care fragmentation was measured using average path length, which describes how efficiently information flows among network members; longer path length indicates greater fragmentation. Terciles based on the level of care fragmentation and multivariable regression were used to analyze the relationship between care fragmentation and LVAD payments and mediation analysis was used to evaluate the role of post-implant infections.

RESULTS

The patient cohort was 81% male, 73% white, 11% Intermacs Profile 1 with mean (SD) age of 63.1 years (11.1). The mean (SD) level of care fragmentation in provider networks was 1.7 (0.2) and mean (SD) payment from admission to 180 days post-discharge was $246,905 ($109,872). Mean (SD) total payments at the lower, middle, and upper terciles of care fragmentation were $250,135 ($111,924), $243,288 ($109,376), and $247,290 ($108,241), respectively. In mediation analysis, the indirect effect of care fragmentation on total payments, through infections, was positive and statistically significant (β=16032.5, p=0.008).

CONCLUSIONS

Greater care fragmentation in the delivery of care surrounding durable LVAD implantation is associated with a higher incidence of infections, and consequently, higher payments for Medicare beneficiaries. Interventions to reduce care fragmentation may reduce the incidence of infections and in turn enhance the value of care for patients undergoing durable LVAD implantation.

Novel Targets for a Combination of Mechanical Unloading with Pharmacotherapy in Advanced Heart Failure

LVAD therapy is an effective rescue in acute and especially chronic cardiac failure. In several scenarios, it provides a platform for regeneration and sustained myocardial recovery. While unloading seems to be a key element, pharmacotherapy may provide powerful tools to enhance effective cardiac regeneration. The synergy between LVAD support and medical agents may ensure satisfying outcomes on cardiomyocyte recovery followed by improved quality and quantity of patient life. This review summarizes the previous and contemporary strategies for combining LVAD with pharmacotherapy and proposes new therapeutic targets. Regulation of metabolic pathways, enhancing mitochondrial biogenesis and function, immunomodulating treatment, and stem-cell therapies represent therapeutic areas that require further experimental and clinical studies on their effectiveness in combination with mechanical unloading.

Impact of Ventricular Arrhythmia on LVAD Implantation Admission Outcomes

INTRODUCTION

Ventricular arrhythmias (VAs) are common after left ventricular assist device (LVAD) implantation though data are mixed on whether these events have an impact on mortality.

METHODS

The National Inpatient Sample (NIS) database from 2002 - 2019 was queried for LVAD implantation admissions. Secondary ICD codes were analyzed to assess for the occurrence of VAs during this admission. Propensity score matching (PSM) was used to control for confounding variables between those with versus without VAs.

RESULTS

The NIS database from 2002 - 2019 contained 43,936 admissions with LVAD implantation. VAs occurred in 19,985 (45.4%) patients. After PSM, the study cohort consisted of 39,989 patients, 19,985 (50.0%) of which had a secondary diagnosis of VA during the admission. When compared to those without VA, those with VA were at no higher risk for in-hospital mortality (adjusted odds ratio 1.011, 99.9% CI 0.956 - 1.069, p = 0.699). Those with a VA were at higher risk for cardiogenic shock and requiring mechanical ventilation, tracheostomy, and percutaneous endoscopic gastrostomy placement. Patients with a VA were also at lower risk for device thrombosis. Conversely, the VA group was at no higher risk for stroke. In comparing trends from 2002 to 2019, the incidence of VAs has increased, while the mortality rate of those with and without VAs has decreased during this same period.

CONCLUSION

In this retrospective study of the NIS database, VAs were common (45.4%) during the LVAD implantation admission. However, the occurrence of VAs during the implantation admission did not alter in-hospital mortality. More longitudinal studies are required to assess the long-term impact of VAs on mortality. In comparing trends from 2002 - 2019, the incidence of VAs has increased, while the mortality rate of those with and without VAs has decreased.

Muscle strength, aerobic capacity, and exercise tolerance are impaired in left ventricular assist devices recipients: A pilot study

Background: Left ventricular assist devices (LVAD) are increasingly being used as a therapy for advanced heart failure, both as a bridge to heart transplant and, given the rapid advances in the LVAD’s functionality and safety, and constant lack in availability of donor organs, as long-term destination therapy. With the diffusion of such therapy, it is crucial to assess patients’ muscle strength, aerobic capacity and exercise tolerance, to improve their functional capacity.

Methods: 38 LVAD recipients (33 men and five women) were included. Exercise testing including a maximal cardiopulmonary exercise test (CPET), handgrip, isometric and isokinetic strength testing of knee and ankle flexion/extension, and Romberg balance test in three conditions (eyes open, eyes closed, double task). Given the small and heterogeneous final sample size, a mostly descriptive statistical approach was chosen.

Results: 12 participants were classified as “Obese” (BMI>29.9). The most common comorbidities were type II diabetes and chronic kidney disease. Only 12 participants were able to successfully complete all the assessments. CPET and isokinetic strength trials were the least tolerated tests, and the handgrip test the best tolerated. Mean VO₂ peak was 12.38 ± 3.43 ml/kg/min, with 15 participants below 50% of predicted VO₂ max, of which 6 below 30% VO₂max. Mean handgrip strength was 30.05 ± 10.61 Kg; 25 participants were below the 25° percentile of their population’s normative reference values for handgrip strength, 10 of which were below the 5° percentile. Issues with the management of the external pack of the LVAD and its influence on the test limited the validity of the balance tests data, therefore, no solid conclusions could be drawn from them. VO₂ peak did not correlate with handgrip strength or with any of the lower limb strength measures.

Conclusion: LVAD recipients show greatly reduced functional capacity and tolerance to exercise and exercise testing, with low overall strength levels. As strength variables appear to be independent from VO₂ peak, different lower limbs strength tests should be explored to find a tolerable alternative in this population, which is subjected to muscle wasting due to old age, reduced tissue perfusion, side effects from the pharmacological therapies, and prolonged periods of bedrest.

Obesity and outcomes after left ventricular assist device implantation-insights from the EUROMACS registry

OBJECTIVES

The objective was to analyze associations between obesity and outcomes after left ventricular assist device implantation.

METHODS

A retrospective analysis of the EUROMACS Registry was performed. Adult patients undergoing primary implantation of a continuous-flow left ventricular assist device between 2006 and 2019 were included (Medtronic HeartWare® HVAD®, Abbott HeartMate II®, Abbott HeartMate 3™). Patients were classified in 4 different groups according to body mass index at the time of surgery (body mass index < 20 kg/m2: n = 254; 20-24.9 kg/m2: n = 1281; 25-29.9 kg/m2: n = 1238; ≥ 30 kg/m2: n = 691).

RESULTS

The study cohort was comprised of 3464 patients. Multivariable Cox proportional cause-specific hazards regression analysis demonstrated that obesity (body mass index ≥ 30 kg/m2) was independently associated with significantly increased risk of mortality (body mass index "≥ 30" vs "20-24.9" kg/m2: hazard ratio 1.36, 95% confidence interval 1.18 to 1.57, overall p < 0.001). Moreover, obesity was associated with significantly increased risk of infection and driveline infection. The probability to undergo heart transplantation was significantly decreased in obese patients (body mass index "≥ 30" vs "20-24.9" kg/m2: hazard ratio 0.59, 95% confidence interval 0.48 to 0.74, overall p < 0.001).

CONCLUSIONS

Obesity at the time of left ventricular assist device implantation is associated with significantly higher mortality and increased risk of infection as well as driveline infection. The probability to undergo heart transplantation is significantly decreased. These aspects should be considered when devising a treatment strategy before surgery.

Third-generation continuous-flow left ventricular assist devices: a comparative outcome analysis by device type

AIMS

Continuous-flow left ventricular assist devices (CF-LVADs) have become a standard of care in end-stage heart failure. Limited data exist comparing outcomes of HeartMate3 (HM3) and HeartWare HVAD (HW). We aimed to compare midterm outcomes of these devices.

METHODS AND RESULTS

Investigator-initiated retrospective-observational comparative analysis of all patients who underwent primary LVAD implantation of either HM3 or HW at our centre between January 2010 and December 2020. Data were derived from a prospective registry. Primary endpoints were all-cause mortality and heart transplantation. Secondary endpoints included device-related major adverse cardiac and cerebrovascular events, which included major bleeding, major neurological dysfunction (defined as persisting neurological impairment for ≥24 h), device-related major infection (excluding driveline infections), major device malfunctions leading to re-intervention or partial device exchange (pump failure, outflow-graft twist or failure, controller failure, battery failure, patient cable failure, but excluding pump thrombosis), and pump thrombosis. Further secondary endpoints included right heart failure, gastrointestinal bleeding, driveline infections, and surgical re-interventions. The secondary outcomes were analysed not only for the first event but also for recurrent events. The analysis included competing risks analysis and recurrent event regression analysis, with adjustment for confounders age, gender, body mass index (BMI), and Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) level. Out of 106 primary CF-LVAD implantations, 36 (34%) received HM3 and 70 (66%) received HW. Median follow-up was 1.48 years [interquartile range 0.67, 2.41]. HM3 was more often implanted in men (91.7% vs. 72.9%, P = 0.024); patients were older (median 61 years [54, 66.5] vs. 52.5 years [43, 60], P < 0.001), had a higher BMI (median 26.7 kg/m² [23.4, 29.0] vs. 24.3 kg/m² [20.7, 27.4], P = 0.013), had more comorbidities, and were more likely targeted for destination therapy (36.1% vs. 14.3%, P = 0.010). Death occurred in 33.3% of HM3 patients, compared with 22.9% of HW patients, P = 0.247 (probability of survival at 4 years, 54.7% vs. 74.1%, P = 0.296). After adjustment for confounders, we observed a significant six-fold risk increase in device malfunctions for HW [hazard ratio (HR) 6.49, 95% confidence interval (CI) [1.89, 22.32], P = 0.003], but no significant differences in pump thrombosis (P = 0.173) or overall survival (P = 0.801).

CONCLUSIONS

Comparing midterm outcomes between HM3 and HW for LVAD support from a prospective registry, HW patients had a significantly higher risk of device malfunctions. No significant differences were evident between devices in overall survival and in respect to most outcomes.

In a large-volume multidisciplinary setting individual surgeon volume does not impact LVAD outcomes

Background

In complex operations surgeon volume may impact outcomes. We sought to understand if individual surgeon volume affects left ventricular assist device (LVAD) outcomes.

Methods

We reviewed primary LVAD implants at an experienced ventricular assist devices (VAD)/transplant center between 2013 and 2019. Cases were dichotomized into a high‐volume group (surgeons averaging 11 or more LVAD cases per year), and a low‐volume group (10 or less per year). Propensity score matching was performed. Survival to discharge, 1‐year survival, and incidence of major adverse events were compared between the low‐ and high‐volume groups. Predictors of survival were identified with multivariate analysis.

Results

There were 315 patients who met inclusion criteria‐45 in the low‐volume group, 270 in the high‐volume group. There was no difference in survival to hospital discharge between the low (91.9%) and high (83.3%) volume matched groups (p = .22). Survival at 1‐year was also similar (85.4% vs. 80.6%, p = .55). There was no difference in the incidence of major adverse events between the groups. Predictors of mortality in the first year included: age (hazards ratio [HR]: 1.061, p < .001), prior sternotomy (HR: 1.991, p = .01), increasing international normalized ratio (HR: 4.748, p < .001), increasing AST (HR: 1.001, p < .001), increasing bilirubin (HR: 1.081, p = .01), and preoperative mechanical ventilation (HR: 2.662, p = .005). Individual surgeon volume was not an independent predictor of discharge or 1‐year survival.

Conclusion

There was no difference in survival or adverse events between high and low volume surgeons suggesting that, in an experienced multidisciplinary setting, low‐volume VAD surgeons can achieve similar outcomes to their high‐volume colleagues.

Impact of surgical approach for left ventricular assist device implantation on postoperative invasive hemodynamics and right ventricular failure

BACKGROUND

Right ventricular failure (RVF) remains one of the major causes of morbidity and mortality after left ventricular assist device (LVAD) implantation. We sought to compare immediate postoperative invasive hemodynamics and the risk of RVF following two different surgical approaches: less invasive surgery (LIS) versus full sternotomy (FS).

METHODS

The study population comprised all 231 patients who underwent implantation of a HeartMate 3 (Abbott) LVAD at our institution from 2015 to 2020, utilizing an LIS (n = 161; 70%) versus FS (n = 70; 30%) surgical approach. Outcomes included postoperative invasive hemodynamic parameters, vasoactive-inotropic score (VIS), RVF during index hospitalization, and 6-month mortality.

RESULTS

Baseline clinical characteristics of the two groups were similar. Multivariate analysis showed that LIS, compared with FS, was associated with the improved cardiac index (CI) at the sixth postoperative hour (p = .036) and similar CI at 24 h, maintained by lower VIS at both timepoints (p = .002). The LIS versus FS approach was also associated with a three-fold lower incidence of in-hospital severe RVF (8.7% vs. 28.6%, p < .001) and need for RVAD support (5.0% vs. 17.1%, p = .003), and with 68% reduction in the risk of 6-month mortality after LVAD implantation (Hazard ratio, 0.32; CI, 0.13-0.78; p = .012).

CONCLUSION

Our findings suggest that LIS, compared with FS, is associated with a more favorable hemodynamic profile, as indicated by similar hemodynamic parameters maintained by lower vasoactive-inotropic support during the acute postoperative period. These findings were followed by a reduction in the risk of severe RVF and 6-month mortality in the LIS group.

Characteristics and Outcomes of Left Ventricular Assist Device Recipients Transplanted Before and After the New Donor Heart Allocation System

BACKGROUND

Concerns about the impact of the new donor heart allocation system on post-transplant outcomes have emerged after its implementation. We sought to evaluate the characteristics and outcomes of left ventricular assist device (LVAD) recipients transplanted before and after the implantation of the new policy on October 18, 2018.

METHODS

Data on bridge to transplantation adult LVAD patients January 2015 and October 2021, with durable LVAD as a (BTT), was queried from the United Network of Organ Sharing (UNOS) registry. The main outcomes were 30-day all-cause mortality, 30-day fatal graft failure, 1-year all-cause mortality, treated acute rejection at one year and renal replacement therapy (RRT) for acute renal failure.

RESULTS

In our study, 7096 patients met the inclusion criteria including 2,435 in the new allocation system. The transplanted patients in the new allocation system era had older donor age, longer ischemic time and higher proportion of newer generation LVADs. Adjusted 30-day all-cause mortality was significantly lower for LVAD recipients in the new allocation system era (2.5% vs 3.6%; sub-hazard ratio [SHR] 0.36, 95% Confidence intervals [CI] 0.27-0.48, p<0.001) without differences in the risk of fatal graft failure and one-year mortality (7.8% vs 9.6%). Significantly lower adjusted 30-day mortality with HVAD and HM3 devices than HM2 in the new allocation system era was found, without differences in one-year mortality. Acute allograft rejection requiring treatment was significantly lower (Odds Ratio 0.78, 95% CI 0.65-0.94, p=0.01) whereas a trend towards higher risk of renal failure requiring RRT was identified.

CONCLUSIONS

Despite changing donor characteristics and longer ischemic times, post-transplant outcomes in LVAD recipients have not worsened with the implementation of the new allocation system and this finding is related to the use of newer generation continuous flow LVADs.

Physiologic Data-Driven Iterative Learning Control for Left Ventricular Assist Devices

Continuous flow ventricular assist devices (cfVADs) constitute a viable and increasingly used therapy for end-stage heart failure patients. However, they are still operating at a fixed-speed mode that precludes physiological cfVAD response and it is often related to adverse events of cfVAD therapy. To ameliorate this, various physiological controllers have been proposed, however, the majority of these controllers do not account for the lack of pulsatility in the cfVAD operation, which is supposed to be beneficial for the physiological function of the cardiovascular system. In this study, we present a physiological data-driven iterative learning controller (PDD-ILC) that accurately tracks predefined pump flow trajectories, aiming to achieve physiological, pulsatile, and treatment-driven response of cfVADs. The controller has been extensively tested in an in-silico environment under various physiological conditions, and compared with a physiologic pump flow proportional-integral-derivative controller (PF-PIDC) developed in this study as well as the constant speed (CS) control that is the current state of the art in clinical practice. Additionally, two treatment objectives were investigated to achieve pulsatility maximization and left ventricular stroke work (LVSW) minimization by implementing copulsation and counterpulsation pump modes, respectively. Under all experimental conditions, the PDD-ILC as well as the PF-PIDC demonstrated highly accurate tracking of the reference pump flow trajectories, outperforming existing model-based iterative learning control approaches. Additionally, the developed controllers achieved the predefined treatment objectives and resulted in improved hemodynamics and preload sensitivities compared to the CS support.

Racial and Sex Inequities in the Use of and Outcomes After Left Ventricular Assist Device Implantation Among Medicare Beneficiaries

Importance

While left ventricular assist devices (LVADs) increase survival for patients with advanced heart failure (HF), racial and sex access and outcome inequities remain and are poorly understood.

Objectives

To assess risk-adjusted inequities in access and outcomes for both Black and female patients and to examine heterogeneity in treatment decisions among patients for whom clinician discretion has a more prominent role.

Design, Setting, and Participants

This retrospective cohort study of 12 310 Medicare beneficiaries used 100% Medicare Fee-for-Service administrative claims. Included patients had been admitted for heart failure from 2008 to 2014. Data were collected from July 2007 to December 2015 and analyzed from August 23, 2020, to May 15, 2022.

Exposures

Beneficiary race and sex.

Main Outcomes and Measures

The propensity for LVAD implantation was based on clinical risk factors from the 6 months preceding HF admission using XGBoost and the synthetic minority oversampling technique. Beneficiaries with a 5% or greater probability of receiving an LVAD were included. Logistic regression models were estimated to measure associations of race and sex with LVAD receipt adjusting for clinical characteristics and social determinants of health (eg, distance from LVAD center, Medicare low-income subsidy, neighborhood deprivation). Next, 1-year mortality after LVAD was examined.

Results

The analytic sample included 12 310 beneficiaries, of whom 22.9% (n = 2819) were Black and 23.7% (n = 2920) were women. In multivariable models, Black beneficiaries were 3.0% (0.2% to 5.8%) less likely to receive LVAD than White beneficiaries, and women were 7.9% (5.6% to 10.2%) less likely to receive LVAD than men. Individual poverty and worse neighborhood deprivation were associated with reduced use, 2.9% (0.4% to 5.3%) and 6.7% (2.9% to 10.5%), respectively, but these measures did little to explain observed disparities. The racial disparity was concentrated among patients with a low propensity score (propensity score <0.52). One-year survival by race and sex were similar on average, but Black patients with a low propensity score experienced improved survival (7.2% [95% CI, 0.9% to 13.5%]).

Conclusions and Relevance

In this cohort study of Medicare beneficiaries hospitalized for HF, disparities in LVAD use by race and sex existed and were not explained by clinical characteristics or social determinants of health. The treatment and post-LVAD survival by race were equivalent among the most obvious LVAD candidates. However, there was differential use and outcomes among less clear-cut LVAD candidates, with lower use but improved survival among Black patients. Inequity in LVAD access may have resulted from differences in clinician decision-making because of systemic racism and discrimination, implicit bias, or patient preference.

Arterial Compliance and Continuous-Flow Left Ventricular Assist Device Pump Function

Durable continuous-flow left ventricular assist devices (cfLVADs) demonstrate superior survival, cardiac functional status, and overall quality of life compared to medical therapy alone in advanced heart failure. Previous studies have not considered the impact arterial compliance may have on pump performance or developed arterial pressure. This study assessed the impact of alterations in arterial compliance, preload, and afterload on continuous-flow pump function and measured hemodynamics using an in-vitro pulsatile mock circulatory loop. Decreased arterial compliance was associated with a significant increase in arterial pressure pulsatility which was not evident in the flow pulsatility, as displayed in pump flow waveforms. There were marked changes in the pump flow waveforms due to the significant alteration in the aortoventricular gradient during diastole according to the changes in compliance. This study demonstrates that changes in systemic blood pressure, afterload, and left ventricular contractility each significantly affects the flow waveform. The association of hypertension with lower aortic compliance results in markedly decreased diastolic flow rates which may be important in contributing to a greater risk of adverse events under cfLVAD support.

LVAD as a Bridge to Remission from Advanced Heart Failure: Current Data and Opportunities for Improvement

Left ventricular assist devices (LVADs) are an established treatment modality for advanced heart failure (HF). It has been shown that through volume and pressure unloading they can lead to significant functional and structural cardiac improvement, allowing LVAD support withdrawal in a subset of patients. In the first part of this review, we discuss the historical background, current evidence on the incidence and assessment of LVAD-mediated cardiac recovery, and out-comes including quality of life after LVAD support withdrawal. In the second part, we discuss current and future opportunities to promote LVAD-mediated reverse remodeling and improve our pathophysiological understanding of HF and recovery for the benefit of the greater HF population.

Does the distance between residency and implanting center affect the outcome of patients supported by left ventricular assist devices? A multicenter Italian study on radial mechanically assisted circulatory support (MIRAMACS) analysis

BACKGROUND

Patients with LVAD require continuous monitoring and care, and since Implanting Centers (ICs) are more experienced in managing LVAD patients than other healthcare facilities, the distance between patient residency and IC could negatively affect the outcomes.

METHODS

Data of patients discharged after receiving an LVAD implantation between 2010 and 2021 collected from the MIRAMACS database were retrospectively analyzed. The population was divided into two groups: A (n = 175) and B (n = 141), according to the distance between patient residency and IC ≤ or >90 miles. The primary endpoint was freedom from Adverse Events (AEs), a composite outcome composed of death, cerebrovascular accident, hospital admission because of GI bleeding, infection, pump thrombosis, and right ventricular failure. Secondary endpoints were incidences of mortality and complications. All patients were followed-up regularly, according to participating center protocols.

RESULTS

Baseline clinical characteristics and indications for LVAD did not differ between the two groups. The mean duration of support was 25.5 ± 21 months for Group A and 25.7 ± 20 months for Group B (p = 0.79). At 3 years, freedom from AEs was similar between Group A and Group B (p = 0.36), and there were no differences in rates of mortality and LVAD-related complications.

CONCLUSIONS

Distance from the IC does not represent a barrier to successful outcomes as long as regular and continuous follow-up is provided.

The Effect of Vocal Intonation Therapy on Vocal Dysfunction in Patients With Cervical Spinal Cord Injury: A Randomized Control Trial

In this study, the vocal intonation therapy (VIT) was compared with the standard respiratory therapy for people suffering from respiratory dysfunction as a result of cervical spinal cord injury (CSCI) to observe its effect on vocal quality. Thirty patients with vocal dysfunction after CSCI with the injury time of more than 3 months were screened for inclusion in the trial, and 18 patients completed the 12-weeks, each participant had 60 sessions in total in the clinical trial. All patients were allocated to the intervention group or the control group. The intervention group received VIT training and the control group received respiratory phonation therapy. Both groups were trained by professional therapists, and the training time was 30 min/day, 5 days/week, for 60 sessions for each group in a total of 12 weeks. In the Baseline (T0), mid-intervention period (after 6 weeks, T1), and after intervention (after 12 weeks, T2), the vocal quality of the two groups of patients was tested with a computer-aided real-time audio analyzer 2.1.6 (Adobe Systems, United States) for Sing-SPL (p &lt; 0.0001), Speech-SPL (p &lt; 0.0001), SNL (p &lt; 0.0001), and F0 (p &lt; 0.0001) of the intervention group were significantly improved compared with the control group. In comparing the spectrometry analysis of vocal quality for the 2 groups of participants, there was a significant difference in the results of Sing-SPL and Speech-SPL acoustic analysis in the intervention group of patients at T2 (after 12 weeks) compared to the control group. Vocal intonation therapy—music therapy can improve the speech sound quality of cervical CSCI patients and provide CSCI patients with a practical, highly operable treatment that has both functional training effects and can bring a pleasant experience that can be promoted in the medical field. This study was approved by the Ethics Committee of China Rehabilitation Research Center (CRRC) (approval No. 2019-83-1) on May 20th, 2019. It was registered with the National Health Security Information Platform, medical research registration, and filing information system (Registration No. MR-11-21-011802) on January 28th, 2021.

Is There a Sex Gap in Outcomes of Comparable Patients Supported with Left Ventricular Assist Devices?

OBJECTIVES

Historically, females were described as suffering from worse outcomes after left ventricular assist device (LVAD) implantation. However, females' preoperative conditions are unique, making direct comparisons with males challenging. This study aimed to select through propensity score (PS) matching two preoperatively comparable populations of females and males and test if any real sex-related difference exists regarding survival and adverse events after LVAD implantation.

METHODS

This retrospective single-center observational study investigated patients who received LVAD implantation between 2010 and 2018. PS matching was applied to balance preoperative heterogeneity between males and females. Primary endpoint was survival at follow-up. Secondary endpoints included perioperative outcomes and LVAD-related adverse events.

RESULTS

92 fully comparable females(n=46) and males(n=46) were selected after PS matching (median age:57 years, min-max:18-75). 26.1% of patients required preoperative mechanical circulatory support. Females needed more intraoperative fresh frozen plasma (p<0.001) and platelets transfusions (p=0.008) compared to males, but postoperative outcomes were comparable between groups. In-hospital, 1-year and 2-year survival were 78.3%, 69.6% and 65.2%, respectively, with no differences between groups. Survival probability remained comparable up to 8 years of follow-up(p=0.35). Overall, females showed a higher rate of strokes(p=0.039) compared to males in the follow-up time.

CONCLUSIONS

After reducing preoperative heterogeneity between females and males, survival after LVAD implantation does not differ based on sex. However, differences might exist in terms of higher transfusions and strokes in females. Reducing preoperative sex disparities and developing intraoperative and anticoagulation strategies which acknowledge sex-related variations might help abolishing differences in LVAD outcomes.

Extracorporeal membrane oxygenation as a bridge to durable mechanical circulatory support or heart transplantation

BACKGROUND

Patients with cardiogenic shock may require extracorporeal membrane oxygenation (ECMO) prior to durable mechanical circulatory support (dMCS) or heart transplantation (HTx).

METHODS

We investigated the clinical characteristics and outcomes of adult patients with ECMO support as bridge to dMCS or HTx between 1/1/13 and 12/31/20.

RESULTS

Of 57 patients who underwent bridging ECMO, 41 (72%) received dMCS (approximately half with biventricular support) and 16 (28%) underwent HTx, 13 (81%) after the 2018 UNOS allocation system change. ECMO → HTx patients had shorter ventilatory time (3.5 vs 7.5 days; p = 0.018), ICU stay (6 vs 18 days; p = 0.001), and less need for inpatient rehabilitation (18.8% vs 57.5%; p = 0.016). The 1-year survival post HTx was 81.3% in the ECMO → HTx group and 86.4% in the ECMO → dMCS group (p = 0.11). For those patients in the ECMO → dMCS group who did not undergo HTx, 1-year survival was significantly lower, 31.6% (p = 0.001).

CONCLUSION

Patients on ECMO who undergo HTx, with or without dMCS bridge, have acceptable post-HTx survival. These findings suggest that HTx from ECMO is a viable option for carefully selected patients deemed acceptable to proceed with definitive advanced therapies, especially in the era of the new UNOS allocation system.

Prevalence, management, and outcomes of haemorrhagic events in left ventricular assist device recipients

AIMS

Left ventricular assist devices (LVADs) have reduced the mortality of patients with advanced heart failure both as bridge-to-transplant and as destination therapy. However, LVADs are associated with various complications, including bleedings, which affect the prognosis. The aim of the study was to explore the prevalence, management, and outcomes of haemorrhagic adverse events in LVAD recipients.

METHODS AND RESULTS

We conducted a retrospective, single-centre, cohort study including all patients who received an LVAD from January 2008 to December 2019 in our tertiary centre (Rangueil University Hospital, Toulouse, France). Bleeding events, death, and heart transplantation were collected from electronic medical files. Eighty-eight patients were included, and 43 (49%) presented at least one bleeding event. Gastrointestinal (GI) bleeding was the most frequent (n = 21, 24%), followed by epistaxis (n = 12, 14%) and intracranial haemorrhage (n = 9, 10%). Bleeding events were associated with increased mortality [hazard ratio (HR) 3.8, 95% confidence interval (CI) 1.5-9.3, P < 0.01], particularly in case of intracranial haemorrhage (HR 14.6, 95% CI 4.2-51.1, P < 0.0001). GI bleedings were associated with a trend towards increased mortality (HR 3.0, 95% CI 0.9-9.3, P = 0.05). Each bleeding episode multiplied the risk of death by 1.8 (95% CI 1.2-2.7, P < 0.01). Finally, only early bleedings (<9 months post-implantation) had an impact on mortality (HR 4.2, 95% CI 1.6-11.1, P < 0.01). Therapeutic management was mainly based on temporary interruption of anticoagulation and permanent interruption of antiplatelet therapy. Invasive management was rarely performed.

CONCLUSIONS

Haemorrhagic events in LVAD recipients are frequent and associated with increased mortality. GI bleedings are the most frequent, and intracranial haemorrhages the most associated with mortality. Management remains empirical requiring more research.

Mechanical Circulatory Support: Primer for Consultant Specialists

Mechanical life support therapies exist in many forms to temporarily replace the function of vital organs. Generally speaking, these tools are supportive therapy to allow for organ recovery but, at times, require transition to long-term mechanical support. This review will examine nonrenal extracorporeal life support for cardiac and pulmonary support as well as other mechanical circulatory support options. This is intended as a general primer and overview to assist nephrologist consultants participating in the care of these critically ill patients who often experience acute renal injury as a result of cardiopulmonary shock and from their exposure to mechanical circulatory support.

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

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

Concept, Design, and Early Prototyping of a Low-Cost, Minimally Invasive, Fully Implantable Left Ventricular Assist Device

Despite evidence associating the use of mechanical circulatory support (MCS) devices with increased survival and quality of life in patients with advanced heart failure (HF), significant complications and high costs limit their clinical use. We aimed to design an innovative MCS device to address three important needs: low cost, minimally invasive implantation techniques, and low risk of infection. We used mathematical modeling to calculate the pump characteristics to deliver variable flows at different pump diameters, turbomachinery design software CFturbo (2020 R2.4 CFturbo GmbH, Dresden, Germany) to create the conceptual design of the pump, computational fluid dynamics analysis with Solidworks Flow Simulation to in silico test pump performance, Solidworks (Dassault Systèmes SolidWorks Corporation, Waltham, MA, USA) to further refine the design, 3D printing with polycarbonate filament for the initial prototype, and a stereolithography printer (Form 2, Formlabs, Somerville, MA, USA) for the second variant materialization. We present the concept, design, and early prototyping of a low-cost, minimally invasive, fully implantable in a subcutaneous pocket MCS device for long-term use and partial support in patients with advanced HF which unloads the left heart into the arterial system containing a rim-driven, hubless axial-flow pump and the wireless transmission of energy. We describe a low-cost, fully implantable, low-invasive, wireless power transmission left ventricular assist device that has the potential to address patients with advanced HF with higher impact, especially in developing countries. In vitro testing will provide input for further optimization of the device before proceeding to a completely functional prototype that can be implanted in animals.

Improved survival of left ventricular assist device carriers in Europe according to implantation eras - results from the PCHF-VAD registry

BACKGROUND AND AIM

Temporal changes in patient selection and major technological developments in have occurred in the field of LVADs, yet analyses depicting this trend are lacking for Europe. We describe the advances of European LVAD programmes from the PCHF-VAD registry across device implantation eras.

METHODS

Of 583 patients from 13 European centres in the registry, 556 patients (mean age 53 ± 12 years, 82% male) were eligible for this analysis. Patients were divided to eras (E) by date of LVAD implantation: E1 from December 2006 to and including December 2012 (6 years), E2 from January 2013 to January 2020 (7 years).

RESULTS

Patients implanted more recently were older with more comorbidities, but less acutely ill. Receiving an LVAD in E2 was associated with improved 1-year survival in adjusted analysis (HR 0.58 [0.35-0.98] p = 0.043). LVAD implantation in E2 was associated with a significantly lower chance of heart transplantation (adjusted HR 0.40 [0.23-0.67], p = 0.001), and lower risk of LVAD-related infections (adjusted HR 0.64, [0.43-0.95], p = 0.027), both in unadjusted and adjusted analyses. The adjusted risk of haemocompatibility-related events decreased (HR 0.60 [0.39-0.91], p = 0.016), while the heart failure-related events increased in E2 (HR 1.67 [1.02-2.75], p = 0.043).

CONCLUSION

In an analysis depicting the evolving landscape of cf-LVAD carriers in Europe over 13 years, a trend towards better survival is seen in the recent years, despite older recipients with more comorbidities, potentially attributable to increasing expertise of LVAD centres, improved patient selection and pump technology. However, a smaller chance of undergoing heart transplantation was noted in the second era, underscoring the relevance of improved outcomes on LVAD support.

Left Ventricular Assist Devices: A Primer for the Non-Mechanical Circulatory Support Provider

Survival after implant of a left ventricular assist device (LVAD) continues to improve for patients with end-stage heart failure. Meanwhile, more patients are implanted with a destination therapy, rather than bridge-to-transplant, indication, meaning the population of patients living long-term on LVADs will continue to grow. Non-LVAD healthcare providers will encounter such patients in their scope of practice, and familiarity and comfort with the physiology and operation of these devices and common problems is essential. This review article describes the history, development, and operation of the modern LVAD. Common LVAD-related complications such as bleeding, infection, stroke, and right heart failure are reviewed and an approach to the patient with an LVAD is suggested. Nominal operating parameters and device response to various physiologic conditions, including hypo- and hypervolemia, hypertension, and device failure, are reviewed.

2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure" replaces the "2013 ACCF/AHA Guideline for the Management of Heart Failure" and the "2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure." The 2022 guideline is intended to provide patient-centric recommendations for clinicians to prevent, diagnose, and manage patients with heart failure.

METHODS

A comprehensive literature search was conducted from May 2020 to December 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (PubMed), EMBASE, the Cochrane Collaboration, the Agency for Healthcare Research and Quality, and other relevant databases. Additional relevant clinical trials and research studies, published through September 2021, were also considered. This guideline was harmonized with other American Heart Association/American College of Cardiology guidelines published through December 2021. Structure: Heart failure remains a leading cause of morbidity and mortality globally. The 2022 heart failure guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with heart failure, with the intent to improve quality of care and align with patients' interests. Many recommendations from the earlier heart failure guidelines have been updated with new evidence, and new recommendations have been created when supported by published data. Value statements are provided for certain treatments with high-quality published economic analyses.

Time Spent Engaging in Health Care Among Patients With Left Ventricular Assist Devices

OBJECTIVES

This study aims to examine a novel patient-centered metric of time spent engaging in left ventricular assist device (LVAD)-related clinical care outside the home.

BACKGROUND

Although LVAD implantation can improve survival and functional capacity in patients with advanced heart failure, this may occur at the expense of significant time spent engaging in LVAD-related health care activities.

METHODS

The authors retrospectively assessed consecutive patients at a single center who received a continuous-flow LVAD between May 9, 2008, and December 31, 2019, and queried health care encounters after implantation, including all inpatient encounters and LVAD-related ambulatory encounters. Patient-level time metrics were determined, including the total number of days with any health care encounter, and the total estimated time spent receiving care. The primary outcome was the proportion (%) of days alive with an LVAD spent engaged in at least 1 health care encounter. The secondary outcome was the proportion (%) of total time alive with an LVAD spent receiving care.

RESULTS

Among 373 patients, the median number of days alive with LVAD was 390 (IQR: 158-840 days). Patients had a median number of 88 (IQR: 45-161) days with ≥1 health care encounter, accounting for 23.2% (IQR: 16.3%-32.4%) of their days alive with an LVAD. A median 6.0% (IQR: 2.1%-14.1%) and 15.0% (IQR: 10.7%-20.0%) of total days alive were spent in inpatient and ambulatory encounters, respectively. Patients spent a median of 592 (IQR: 197-1,257) hours receiving care, accounting for 5.6% (IQR: 2.2%-12.7%) of their total time alive with an LVAD.

CONCLUSIONS

LVAD patients spent more than 1 of every 5 days engaging in health care. Our findings may inform strategies to improve efficiency of postdischarge care delivery and expectations for post-treatment care.

Advancing Quality Metrics for Durable Left Ventricular Assist Device Implant: Analysis of the Society of Thoracic Surgeons Intermacs Database

BACKGROUND

Patients undergoing left ventricular assist device (LVAD) implantation are at risk for death and postoperative adverse outcomes. Interhospital variability and concordance of quality metrics were assessed using the Society of Thoracic Surgeons Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs).

METHODS

A total of 22 173 patients underwent primary, durable LVAD implantation across 160 hospitals from 2012 to 2020, excluding hospitals performing <10 implant procedures. Observed and risk-adjusted operative mortality rates were calculated for each hospital. Outcomes included operative and 90-day mortality, a composite of adverse events (operative mortality, bleeding, stroke, device malfunction, renal dysfunction, respiratory failure), and secondarily failure to rescue. Rates are presented as median (interquartile range [IQR]). Hospital performance was evaluated using observed-to-expected (O/E) ratios for mortality and the composite outcome.

RESULTS

Interhospital variability existed in observed (median, 7.2% [IQR, 5.1%-9.6%]) mortality. The rates of adverse events varied across hospitals: major bleeding, 15.6% (IQR, 11.4%-22.4%); stroke, 3.1% (IQR, 1.6%-4.7%); device malfunction, 2.4% (IQR, 0.8%-3.7%); respiratory failure, 10.5% (IQR, 4.6%-15.7%); and renal dysfunction, 6.4% (IQR, 3.2%-9.6%). The O/E ratio for operative mortality varied from 0.0 to 6.1, whereas the O/E ratio for the composite outcome varied from 0.28 to 1.99. Hospital operative mortality O/E ratios were more closely correlated with the 90-day mortality O/E ratio (r = 0.74) than with the composite O/E ratio (r = 0.12).

CONCLUSIONS

This study reported substantial interhospital variability in performance for hospitals implanting durable LVADs. These findings support the need to (1) report hospital-level performance (mortality, composite) and (2) undertake benchmarking activities to reduce unwarranted variability in outcomes.

Bring it on: Top five antimicrobial stewardship challenges in transplant infectious diseases and practical strategies to address them

Antimicrobial therapies are essential tools for transplant recipients who are at high risk for infectious complications. However, judicious use of antimicrobials is critical to preventing the development of antimicrobial resistance. Treatment of multidrug-resistant organisms is challenging and potentially leads to therapies with higher toxicities, intravenous access, and intensive drug monitoring for interactions. Antimicrobial stewardship programs are crucial in the prevention of antimicrobial resistance, though balancing these strategies with the need for early and frequent antibiotic therapy in these immunocompromised patients can be challenging. In this review, we summarize 5 frequently encountered transplant infectious disease stewardship challenges, and we suggest strategies to improve practices for each clinical syndrome. These 5 challenging areas are: asymptomatic bacteriuria in kidney transplant recipients, febrile neutropenia in hematopoietic stem cell transplantation, antifungal prophylaxis in liver and lung transplantation, treatment of left-ventricular assist device infections, and Clostridioides difficile infection in solid-organ and hematopoietic stem-cell transplant recipients. Common themes contributing to these challenges include limited data specific to transplant patients, shortcomings in diagnostic testing, and uncertainties in pharmacotherapy.