Predicting outcomes following short-term ventricular assist device implant with the MELD-XI score.

BACKGROUND: Short-term continuous flow (STCF) ventricular assist devices (VADs) are utilized in adults with cardiogenic shock; however, mortality remains high. Previous studies have found that high pre-operative MELD-XI scores in durable VAD patients are associated with mortality. The use of the MELD-XI score to predict outcomes in STCF-VAD patients has not been explored. We sought to determine the relationship between MELD-XI and outcomes in adults with STCF-VADs. METHODS: This was a retrospective review of adults implanted with STCF-VADs between 2009 and 2019. Receiver operating characteristic (ROC) analysis was performed to predict outcomes and Kaplan-Meier analysis was done to assess survival. RESULTS: Seventy-nine patients were included with a median MELD-XI score of 21.2 (IQR 13.5, 27.0). Patients with an unsuccessful wean from support (p < 0.001) or major post-operative bleeding (p = 0.03) had significantly higher pre-implant MELD-XI scores. The optimal MELD-XI cut-point for mortality was 24.9 with 27.8 for major bleeding. Survival was worse among patients in the high-risk MELD-XI group, however, not statistically significant (p = 0.09). Prior ECMO support, but not MELD-XI, was an independent predictor of unsuccessful wean (p = 0.03). CONCLUSIONS: Pre-operative MELD-XI score was a moderate predictor of unsuccessful wean with limited utility in predicting bleeding in patients on STCF-VAD support. This scoring system may be useful in the clinical setting for pre-implant risk stratification and counseling among patients and outcomes.

Family perspectives of ex situ heart perfusion.

BACKGROUND: Pediatric patients awaiting a heart transplant have high waitlist mortality. Several strategies have been utilized to decrease waiting times, but a mortality risk still exists. New medical technologies may improve waiting times and associated mortality. Ex situ heart perfusion (ESHP) is one such technology, which can decrease the impact of cold ischemia on the donor heart and allow for a longer out-of-body time. Adoption of such technology in pediatric heart transplantation will require support from end users, including patient and families. The aim of this qualitative study was to report the perspectives of families with experience related to pediatric HTx toward ESHP. METHODS: Semistructured interviews were conducted with 12 parents or guardians of children who were awaiting or received heart transplantation. Interviews were transcribed, and data were analyzed using qualitative content analysis. RESULTS: Participants expressed varied awareness and knowledge of ESHP. Independent of their understanding of ESHP, all purported that ESHP was an excellent idea and that this technology should be implemented in the pediatric population. They did not identify fundamentally different ethical issues or concerns for ESHP being used relative to other medical technologies. Overall, most participants described consent processes for ESHP should be like any other procedure. All agreed that the surgeon should continue to describe the overall health of the donor heart, provide their medical recommendations, and allow families to have the final say. CONCLUSIONS: The concepts described by the parents and guardians are important in moving this novel technology forward. This information will serve the basis for knowledge translation that will provide educational resources to broaden the understanding and reach of ESHP.

Prospective examination of HLA sensitization after VAD implantation in children and adults.

BACKGROUND: Ventricular assist devices (VADs) have improved survival to heart transplantation (HTx). However, VADs have been associated with development of antibodies against human leukocyte antigen (HLA-Ab) which may limit the donor pool and decrease survival post-HTx. Since HLA-Ab development after VAD insertion is poorly understood, the purpose of this prospective single-center study was to quantify the incidence of and evaluate risk factors for HLA-Ab development across the age spectrum following VAD implantation. METHODS: Adult and pediatric patients undergoing VAD placement as bridge to transplant or transplant candidacy between 5/2016 and 7/2020 were enrolled. HLA-Ab were assessed pre-VAD and at 1-, 3-, and 12-months post-implant. Factors associated with HLA-Ab development post-VAD implant were explored using univariate and multivariate logistic regression. RESULTS: 15/41 (37%) adults and 7/17 (41%) children developed new HLA-Ab post-VAD. The majority of patients (19/22) developed HLA-Ab within two months of implant. New class I HLA-Ab were more common (87% adult, 86% pediatric). Prior pregnancy was strongly associated with HLA-Ab development in adults post-VAD (HR 16.7, 95% CI 1.8-158, p = 0.01). Of the patients who developed new HLA-Ab post-VAD, in 45% (10/22) the HLA-Ab resolved while in 55% (12/22) the HLA-Ab persisted. CONCLUSION: More than one-third of adult and pediatric VAD patients developed new HLA-Ab early after VAD implant with the majority having class I antibodies. Prior pregnancy was strongly associated with post-VAD HLA-Ab development. Further studies are needed to predict regression or persistence of HLA-Ab developed post-VAD, to understand modulation of individuals' immune responses to sensitizing events, and to determine whether transiently detected HLA-Ab post-VAD recur and have long-term clinical impact post-heart transplantation.

The Impact of Ex Situ Heart Perfusion in Pediatric Transplantation: An Analysis of the OPTN Database.

Ex situ heart perfusion (ESHP) has increased the pool of donors in adults. However, this is not true in pediatrics due to lack of devices. Therefore, we sought to understand organ refusal in pediatrics and estimate donor heart usage with ESHP. Donor hearts offered to pediatrics were identified from the Organ Procurement and Transplantation Network Database (2000-2019). A linear regression model was built to predict average travel speed, and the extended maximum permitted distance with ESHP was calculated. This extended distance was compared with the policy for maximum travel distance. There were 33,708 donor offers (n = 10,807 hearts) to pediatric programs [24.1% (n = 2,604) transplanted]. Six percent of the offers (n = 1,832) (n = 771 hearts) were turned down due to distance, with 676 of the hearts never transplanted. Based on the modeling and using an ESHP time of 5.5 hours, 84% (n = 570/676) of hearts turned down due to distance could be utilized by pediatric programs. This proportion increased to 100% with 10 hours of support time. By addressing prolonged ischemic time due to distance, ESHP has the potential to increase the number of donors utilized in pediatric candidates. Although no device exists for pediatrics, this analysis lends support to the importance of developing this technology.

Ex situ heart perfusion for optimization of pediatric donor organ utilization: Attitudes and perceptions.

BACKGROUND: Children with heart failure have the highest mortality while awaiting transplantation. Ex situ heart perfusion (ESHP), a method for continuous perfusion of the donor heart, has the potential to improve access to transplant by increasing travel distance between donor and recipient. An adult ESHP device is currently available, but as of yet there is no pediatric device. The aim of this study was to evaluate current knowledge of ESHP among pediatric heart transplant practitioners, define potential barriers, and identify uses of this novel technology. METHODS: An electronic survey was developed to assess perspectives of international pediatric heart transplant stakeholders (n = 68) on ESHP. Select questions were analyzed to evaluate for associations between groups of respondents and patterns of response. RESULTS: Most respondents were familiar but <10% had clinically utilized ESHP. There was optimism that ESHP could decrease waitlist mortality. Respondents were concerned about potential device malfunction and lack of long-term outcomes. There were no differences found in terms of ESHP familiarity among age groups, practitioner center volume, country of work, or discipline. CONCLUSIONS: ESHP has the potential to expand the pediatric heart donor pool and decrease waitlist mortality. More education on outcomes and risks/benefits is needed in order to promote widespread adoption.

The Impact of Ex Situ Heart Perfusion in Pediatric Transplantation: An Analysis of the United Network for Organ Sharing Registry.

Ex situ heart perfusion (ESHP) has increased the pool of donors in adults. However, this is not true in pediatrics due to lack of devices. Therefore, we sought to understand organ refusal in pediatrics and estimate donor heart usage with ESHP. Donor hearts offered to pediatrics were identified from the United Network for Organ Sharing (UNOS) Database (2000-2019). A linear regression model was built to predict average travel speed, and the extended maximum permitted distance with ESHP was calculated. This extended distance was compared with the policy for maximum travel distance. There were 33,708 donor offers (n = 10,807 hearts) to pediatric programs (24.1% [n = 2,604] transplanted). Six percent of the offers (n = 1,832) (n = 771 hearts) were turned down due to distance, with 676 of the hearts never transplanted. Based on the modeling and using an ESHP time of 5.5 hours, 84% (n = 570/676) of hearts turned down as distance could be utilized by pediatric programs. This proportion increased to 100% with 10 hours of support time. By addressing prolonged ischemic time due to distance, ESHP has the potential to increase the number of donors utilized in pediatric candidates. While no device exists for pediatrics, this analysis lends support to the importance of developing this technology.

Barriers and misconceptions of ex situ heart perfusion in pediatric donation.

BACKGROUND: Despite efforts, pediatric HTx candidates continue to have high waitlist mortality due to limited donor availability. However, there is a significant number of offered hearts not used due to concerns of viability. ESHP is a method for continuous perfusion of the donor heart that allows assessment and extended out-of-body time. It is imperative to understand healthcare stakeholders' perspectives on ESHP for implementation. Therefore, the aims of this qualitative study were to: (1) Explore pediatric stakeholders' perspectives toward ESHP; and (2) Identify barriers to widespread adoption of this technology. METHODS: Virtual focus groups were completed with pediatric HTx healthcare professional stakeholders. Following transcription of audio-recordings, the material was analyzed using content analysis. RESULTS: Four focus groups were completed with 17 participants, representing 12 institutions and three countries. Focus groups revealed varied understanding of both current and potential uses of ESHP. Participants did see the potential benefits of extending out-of-body time for and the ability to evaluate donor heart quality. However, concerns were expressed relating to patient selection, wait-list times, post-HTx outcomes, adverse events, and technical issues. These were felt to be important to understand in order to justify the costs of ESHP and impact on the healthcare system. CONCLUSIONS: This project represents the first qualitative formative evaluation of ESHP in pediatrics. The knowledge gained from stakeholders will form the basis for education initiatives, clinical trial design, and roll-out of new ESHP technologies designed for pediatrics.

Administrative Databases: Friend or Foe in Paediatric Cardiomyopathy.

Background: Cardiomyopathy (CM) is a rare childhood disease associated with morbidity and mortality. Limited data exist on paediatric CM in Canada. Given the rare nature, single-centre studies are not sufficiently powered to address important questions. Therefore, administrative health data may serve as a resource for the study of childhood CM. The goal of this study was to validate the accuracy of International Classification of Diseases (ICD)-based algorithms to identify paediatric CM in health databases using a clinical registry as the gold standard. Methods: The clinical registry was compiled from outpatient and inpatient records at the Stollery Children's Hospital (January 1, 2013, to December 31, 2021). Patients were categorized as having CM or screened without CM. Data were linked to administrative health databases using the patient's Unique Lifetime Identifier. Algorithms based on the presence of ICD, 10th Revision, codes for CM were then evaluated, and cross-tabulations against the clinical registry were generated. Accuracy, positive predictive value, negative predictive value, sensitivity, and specificity were calculated. Results: The clinical registry had 90 patients with CM and 249 screened without CM. The algorithms ruled out CM (high negative predictive value) but had variability in the ability to diagnose CM positive predictive value. The algorithm that performed the best was based on a diagnosis of CM in a hospitalization or 2 ambulatory visits. Conclusions: A combination of inpatient and outpatient databases can be used, with acceptable accuracy, to identify paediatric patients with CM. This finding allows for the use of the identified algorithm for the comprehensive study of paediatric CM in Canada.

Contexte: La cardiomyopathie (CM) est une maladie rare de l'enfance associée à des taux élevés de morbidité et de mortalité et sur laquelle les données sont limitées en contexte canadien. En raison de la rareté de cette maladie, les études monocentriques ne peuvent atteindre la puissance statistique nécessaire pour répondre à certaines questions importantes. Les données administratives sur la santé peuvent donc constituer une ressource intéressante pour examiner la CM chez les enfants. La présente étude visait à valider l'exactitude d'algorithmes fondés sur la Classification internationale des maladies (CIM) pour repérer les cas de CM pédiatrique dans des bases de données sur la santé, en utilisant un registre clinique comme référence. Méthodologie: Un registre clinique a été élaboré à partir des dossiers de clinique interne et externe du Stollery Children's Hospital (du 1er janvier 2013 au 31 décembre 2021). Les patients ont été classés en deux catégories : atteints de CM ou dépistés sans CM. Les données ont été liées aux bases de données administratives sur la santé en utilisant le numéro d'identification unique des patients (Unique Lifetime Identifier). Des algorithmes fondés sur les codes de la CIM-10 ont été évalués et des analyses croisées avec le registre clinique ont été réalisées. L'exactitude, la valeur prédictive positive (VPP), la valeur prédictive négative (VPN), la sensibilité et la spécificité des algorithmes ont été calculées. Résultats: Le registre clinique comprenait 90 patients atteints de CM et 249 patients dépistés sans CM. Les algorithmes permettaient d'exclure correctement la CM (VPN élevée), mais leur capacité à établir le diagnostic de CM variait (VPP). L'algorithme le plus performant était fondé sur l'attribution d'un code diagnostique de CM lors d'une hospitalisation ou de deux visites ambulatoires. Conclusions: La combinaison de bases de données sur les hospitalisations et sur les soins externes peut être utilisée pour identifier les enfants atteints de CM avec une exactitude acceptable. Cette observation corrobore l'utilisation de l'algorithme ciblé pour réaliser une étude exhaustive de la CM chez l'enfant au Canada.

The Assessment of Driving Fitness Using an On-Road Evaluation in Patients With Cirrhosis.

INTRODUCTION: The association between cirrhosis and driving performance is of particular clinical relevance because of the life-threatening safety issues both for the driver with cirrhosis and the general public. Study aims were to assess (i) driving competency through the use of an in-office computerized battery and on-road driving assessment (DriveABLE) and (ii) the association between minimal hepatic encephalopathy (MHE), in-office paper-pencil tools, and additional measures (e.g., frailty, depression, cognitive testing) with unsafe driving. METHODS: Patients were prospectively recruited from 2 tertiary care liver clinics. In-office tests and in-office and on-road assessments of driving competence were completed. The χ 2 test and 1-way analysis of variance were used to analyze differences among those with and without MHE. Logistic regression was used to evaluate predictors of an indeterminate/fail result on the in-office computerized driving assessment battery (DriveABLE Cognitive Assessment Tool [DCAT]). RESULTS: Eighty patients participated with a mean age of 57 years, 70% male, 75% Child-Pugh B/C, and 36% with a history of overt hepatic encephalopathy. Thirty percent met MHE criteria on both the psychometric hepatic encephalopathy score and the Stroop app tests. Only 2 patients (3%) were categorized as "unfit to drive" in the on-road driving test, one with MHE and the other without. Fifty-eight percent of the patients were scored as indeterminate/fail on the DCAT. This corresponded to a higher mean number of on-road driving errors (5.3 [SD 2.1] vs 4.2 [SD 1.6] in those who passed the DCAT, P = 0.01). Older age (odds ratio 1.3; confidence interval 1.1, 1.5; P = 0.001) and MHE by Stroop/psychometric hepatic encephalopathy score (odds ratio 11.0; confidence interval 2.3, 51.8; P = 0.002) were independently predictive of worse performance on the DCAT. DISCUSSION: Worse performance in in-office testing was associated with worse scores on a computerized driving assessment battery and more on-road driving errors, but in-office tools were insufficient to predict on-road driving failures. A diagnosis of MHE should not be used alone to restrict driving in patients with cirrhosis. At-risk patients require on-road driving tests under the supervision of driving regulatory agencies. Future studies should continue to refine and evaluate in-office or at-home testing to predict driving performance.

Ventricular assist device support following pediatric heart transplantation.

BACKGROUND: VAD support for early graft failure after HTx is a rare event in pediatrics. METHODS: We retrospectively describe our single-center experience with post-HTx VAD support in a cohort of patients transplanted between 01/05 and 12/20. RESULTS: Nine patients underwent VAD insertion in the early post-HTx period [median age 6.1 years (Range 0.3-20.3), median weight 17.6 kg (Range 3.5-65.0), and congenital heart disease (67%)]. Of the nine patients with early graft failure, almost half (44%) were implanted after 2015 and all of these patients had a pre-HTx plan for possible post-transplant VAD insertion. Time to VAD implant was a median of 0 day (Range 0-11). Total time on VAD support was a median of 12 days (Range 3.0-478.0). Two-thirds (n = 6; 67%) of the patients were weaned from support, retransplanted (11%) and two patients died (22%). In all of the patients where post-HTx VAD was anticipated there was 100% survival. CONCLUSIONS: In this small patient series, post-HTx VAD was a useful measure in selected patients especially with pre-HTx planning. However, more shared experiences to verify these findings are needed.

Decreasing driveline infections in patients supported on ventricular assist devices: a care pathway approach.

BACKGROUND: Driveline infections (DLIs) are a common adverse event in patients on ventricular assist devices (VADs) with incidence ranging from 14% to 59%. DLIs have an impact on patients and the healthcare system with efforts to prevent DLIs being essential. Prior to our intervention, our program had no standard driveline management presurgery and postsurgery. The purpose of this Quality Improvement (QI) initiative was to reduce DLIs and related admissions among patients with VAD within the first year post implant. METHODS: In anticipation of the QI project, we undertook a review of the programs' current driveline management procedures and completed a survey with patients with VAD to identify current barriers to proper driveline management. Retrospective data were collected for a pre-QI intervention baseline comparison group, which included adult patients implanted with a durable VAD between 1 January 2017 and 31 July 2018. A three-pronged care pathway (CP) was initiated among patients implanted during August 2018 to July 2019. The CP included standardised intraoperative, postoperative and predischarge teaching initiatives and tracking. Using statistical process control methods, DLIs and readmissions in the first year post implant were compared between patients in the CP group and non-CP patients. P-charts were used to detect special cause variation. RESULTS: A higher proportion of CP group patients developed a DLI in the first year after implant (52% vs 32%). None developed a DLI during the index admission, which differed from the non-CP group and met criteria for special cause variation. There was a downward trend in cumulative DLI-related readmissions among CP group patients (55% vs 67%). There was no association between CP compliance and development of DLIs within 1 year post implant. CONCLUSION: The CP did not lead to a reduction in the incidence of DLIs but there was a decrease in the proportion of patients with DLIs during their index admission and those readmitted for DLIs within 1 year post implant. This suggests that the CP played a role in decreasing the impact of DLIs in this patient population. However, given the short time period of follow-up longer follow-up will be required to look for sustained effects.

Use of Photovoice to Explore Pediatric Patients with Hypertrophic Cardiomyopathy and their Parents' Perceptions of a Heart-Healthy Lifestyle.

Background Heart-healthy lifestyles promote lifelong cardiovascular health. However, patients with hypertrophic cardiomyopathy are often advised to avoid strenuous exercise because of the risk of sudden cardiac death. Given these restrictions, this study explored youth and parent perceptions of a heart-healthy lifestyle and the barriers and facilitators to this lifestyle. Methods and Results Youth and parents were purposefully recruited at 2 Canadian hospitals for this photovoice project. Participants were given cameras and took pictures of everyday heart-healthy or heart-unhealthy choices. Photos were discussed during one-on-one qualitative interviews with youth and parents separately to understand the photos' meaning and significance. Inductive descriptive thematic analysis was employed. A total of 16 youth (median age, 14.4 years [range, 10.5-17.7 years]; 63% boys) and 16 parents (100% women) participated. A total of 15 youth were activity restricted. Data analysis revealed 7 categories organized into perceptions of healthy living (health is holistic and individualized) and factors influencing engagement in healthy living (self-awareness, ownership and autonomy, feeling restricted and peer pressure, support from parents, and support from the cardiologist). Participants had a complex understanding of health and discussed the importance of physical, mental, and social well-being. Youth used self-awareness and taking responsibility as facilitators of healthy living. Healthy living was shaped by peers, parent role-modeling, and cardiologist recommendations. Conclusions This study depicts the realities for youth with hypertrophic cardiomyopathy and can be used to inform the development of responsive interventions. Holistic, patient-specific interventions may be more successful, and strategies such as shared decision making may be important to promote self-awareness and autonomy.

Paracorporeal Support in Pediatric Patients: The Role of the Patient-Device Interaction.

BACKGROUND: Ventricular assist devices are important in the treatment of pediatric heart failure. Although paracorporeal pulsatile (PP) devices have historically been used, there has been increased use of paracorporeal continuous (PC) devices. We sought to compare the outcomes of children supported with a PP or PC, or combination of devices. METHODS: A retrospective review (2005 to 2019) was made of patients less than 19 years of age from a single center who received a PC, PP, or combination of devices. Patient characteristics were compared between device strategies, and Kaplan-Meier survival analysis was performed. RESULTS: Sixty-six patients were included: 62% male; 62% non-congenital heart disease; median age 0.9 years (interquartile range, 0.2 to 4.9); and median weight 8.5 kg (interquartile range, 4.3 to 17.7 kg). The PC devices were used in 45% of patients, PP in 35%, and a combination in 20%. Patients on PC devices had a lower median weight (P = .02) and a higher proportion of congenital heart disease (P = .02), and more patients required pre-ventricular assist device dialysis (P = .01). There was no difference in pre-ventricular assist device extracorporeal membrane oxygenation use (P = .15). There was a difference in survival among the three device strategies (P = .02). CONCLUSIONS: Differences in survival were evident, with patients on PC support having worse outcomes. Transition from PC to a PP devices was associated with a survival advantage. These findings may be driven by differences in patient characteristics across device strategies. Further studies are required to confirm these findings and to better understand the interaction between patient characteristics and device options.

Video Capsule Endoscopy in a Pediatric Patient With Hematemesis While on Ventricular Assist Device Support.

We report the first case of video capsule endoscopy usage to diagnose gastrointestinal bleeding in a pediatric patient on a ventricular assist device. The outcomes of this case are consistent with the findings of reports in adult patients, showing no patient complications, no pacemaker or ventricular assist device interactions, and successful identification of a gastrointestinal source of bleeding. Use of video capsule endoscopy in this patient changed the management plan and eliminated the need for further invasive investigations highlighting the potential utility of this diagnostic method in this patient population.

Human Leukocyte Antigen Antibody Sampling in Ventricular Assist Device Recipients: Are We Talking?

BACKGROUND: Ventricular assist devices (VADs) are commonly used as a bridge to transplantation but may yield HLA sensitization. We evaluated the prevalence of HLA antibody (Ab) sampling pre- and post-VAD placement in pediatric and adult patients and notification of VAD status to the HLA laboratory. METHODS: All pediatric and adult patients who received a first-time VAD between 2005 and 2013 were included in this single-center retrospective review. Data were collected from the University of Alberta Hospital histocompatibility laboratory's information system and a local VAD database. RESULTS: In total, 106 patients were included (40 pediatric, median 3.0 years [interquartile range, 0.3-10.7]; 66 adult, 55.0 years [46.8-61.2]). HLA Ab sampling within 1-month pre-VAD occurred in 70% of pediatric and 79% of adult recipients (P = .215). Testing within 1 month of VAD placement occurred in 89% of pediatric and 67% of adult recipients (P = .012). For those with HLA Ab sampling within 30 days postimplant, notification to the HLA laboratory of VAD status occurred in 19 of 27 (70%) pediatric and 24 of 33 (73%) adult patients (P = .533). Of patients transplanted post VAD with HLA Ab samples collected, 12 of 28 (43%) and 13 of 38 (34%) adult recipients did not have notification of VAD status to the HLA laboratory (P = .322). CONCLUSIONS: There were inconsistencies in HLA Ab sampling and communication to the HLA laboratory surrounding VAD placement. Standardization of both HLA Ab assessment frequency after VAD implantation and communication regarding changes in clinical status and the occurrence of key sensitizing events such as VAD placement are imperative as patients await transplantation.

Discharge and Readmission to the Pediatric Cardiac ICU in Pediatric Patients With Durable Ventricular Assist Devices.

OBJECTIVES: Pediatric patients implanted with a durable ventricular assist device are initially managed in the pediatric cardiac ICU but are eligible for discharge to the ward. Our objectives were to characterize discharge and readmission of ventricular assist device patients to the pediatric cardiac ICU, identify risk factors for readmission, and determine whether discharge or readmission is associated with mortality. DESIGN: Retrospective study. SETTING: Stollery Children's Hospital. PATIENTS: Patients implanted with a durable ventricular assist device at less than 18 years old between 2005 and 2016. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 44 patients who underwent ventricular assist device implantation at a median age of 3.7 years (interquartile range, 0.6-9.0 yr), with the most common etiology being noncongenital heart disease (76.7%). Median time of total ventricular assist device support was 110.0 days (interquartile range, 42.3-212.3 d) with the median index pediatric cardiac ICU stay being 34.0 days (interquartile range, 19.8-81.0 d). Thirty patients (68.0%) were discharged to the ward with 18 (60.0%) having at least one readmission. The median time to first readmission was 18.0 days (interquartile range, 14.8-109.8 d) with a median of two readmissions per patient (interquartile range, 1.0-3.0). The most common reason for readmission was pump thrombosis (30.4%), followed by neurologic dysfunction (23.9%). There were no statistically significant pre- or post-implant factors associated with readmission, and readmission was not associated with mortality (p = 0.600). Univariate Kaplan-Meier survival analysis indicated that use of pre-implant extracorporeal membrane oxygenation, post-implant continuous renal replacement therapy, as well as failure to be discharged from the index pediatric cardiac ICU stay were associated with mortality. CONCLUSIONS: Readmissions to the pediatric cardiac ICU occurred in 60.0% of pediatric patients on durable ventricular assist devices with the first readmission occurring within a month of discharge from the index pediatric cardiac ICU stay. While readmission was not associated with mortality, lack of discharge from index pediatric cardiac ICU stay was likely due to a worse pre-implant clinical status.

End-Stage Liver Disease Models and Outcomes in Pediatric Patients Supported With Short-Term Continuous-Flow Ventricular Assist Devices.

Short-term continuous-flow ventricular assist devices (STCF-VADs) are increasingly being utilized in pediatrics. End-stage liver disease (ELD) models have been associated with outcomes in adult patients on mechanical circulatory support. We sought to determine the relationship between outcomes in children on STCF-VADs and three ELD models: model for end-stage liver disease-excluding international normalized ratio (MELD-XI; all) and MELD-XI (> 1 year), PELD, and a novel score, PedMELD-XI. All patients (< 19 years) supported with STCF-VADs, between June 2009 and December 2016 were included. The MELD-XI, PELD, and PedMELD-XI scores were calculated and their association with adverse events and a composite measure of death, major bleeding, and neurologic dysfunction was analyzed. Of 32 patients, median age was 0.57 years (interquartile range [IQR], 0.10-4.43), median weight was 7.15 kg (IQR, 3.68-16.53), 53.1% had congenital heart disease, and 53.1% were male. In total, 78.1% patients experienced an adverse event (78.1% a major bleed, 25.0% neurologic dysfunction, and 15.6% death). The median MELD-XI score was 11.17 (IQR, 9.44-30.01), MELD-XI (>1 year) 9.44 (IQR, 9.44-24.33), PELD 6.00 (IQR, 4.00-13.75), and PedMELD-XI -14.91 (IQR, -18.85 to -12.25). A higher MELD-XI for all ages (13.80 vs. 9.44, p = 0.037) and less negative PedMELD-XI (-14.16 vs. -19.34, p = 0.028) scores were significantly associated with bleeding and the composite outcome. PedMELD-XI was significantly associated with death (-12.87 vs. -16.84, p = 0.041) while a trend was seen for increased MELD-XI in all ages being associated with death (31.52 vs. 10.11, p = 0.051). Last, there was no association with the models and neurologic events. MELD-XI and PedMELD-XI were significantly associated with major bleeding and the composite endpoints with PedMELD-XI also being associated with death. These results suggest that ELD models can be used to predict outcomes in this specific patient population, however, further analysis in a larger population is required.

Bivalirudin Experience in a Heterogeneous Ventricular Assist Device Population.

Ventricular assist devices (VADs) are an increasingly common therapy for end-stage heart failure across all ages as a bridge to recovery or transplant and more recently as destination therapy. With increasing experience and difficulties with establishing therapeutic heparin levels, we have begun to explore the effectiveness of direct thrombin inhibitors in this patient population. This is a retrospective review of all long-term VAD patients, both adult and pediatric, who were anticoagulated with bivalirudin between January 2009 and January 2016. The starting dose was 0.3 mg/kg/hr, and dose was titrated for a goal partial thromboplastin time (PTT) of 70-100. There were 14 patients (13 males, 5 ≤18 years) with 17 episodes of bivalirudin therapy. The median age on initiation was 45 years (range, 15 days-67 years) with 10 episodes associated with a HeartWare HVAD, five a HeartMate II, and two with a Berlin Heart EXCOR. The predominant indication of bivalirudin therapy was suspected pump thrombosis (13/17). The median time from VAD insertion to initiation of bivalirudin was 116 days (range, 3-1,870) with the median duration of therapy being 21 days (range, 3-113). In patients with pump thrombosis, the mean baseline lactate dehydrogenase (LDH) was 229 ± 64 U/L, peak 690 ± 380 U/L, and decreased to 330 ± 243 U/L when bivalirudin was stopped. The outcomes following suspected pump thrombosis included: transitioned to warfarin (n = 7), death in two destination therapy patients who did not undergo pump exchange, transplantation (n = 2), and pump exchange (n = 2). A major bleeding complication occurred in only one patient. Our experience highlights the potential use of bivalirudin in a heterogenous VAD population. Although these initial results suggest some potential role for direct thrombin inhibitors for use in long-term VADs, larger prospective studies are required to support these preliminary observations and to determine who may benefit from direct thrombin inhibitors (DTIs) and the side effect profile in this patient population.

Preoperative Predictors of Mortality in Short-Term Continuous-Flow Ventricular Assist Devices.

Short-term continuous-flow ventricular assist devices (STCF-VADs) are increasingly being utilized to support critically ill patients, despite limited information regarding overall outcomes. All adult patients supported with an STCF-VAD between June 2009 and December 2015 were included in this retrospective single-center study. Associations between preoperative characteristics and unsuccessful bridge (death on device or within 30 days postdecannulation) were assessed using logistic regression. A total of 61 patients (77% male) were identified with a median age at implant of 54.6 years. Left VADs were implanted in 51%, right VADs in 21%, and both VADs in 28%, and patients were supported for a median of 11 days. Overall, 23% were weaned to recovery, 13% underwent heart transplantation, 16% converted to long-term VADs, and 48% had an unsuccessful bridge. In multivariable analysis, only renal insufficiency or dialysis (odds ratio = 7.53; p = 0.002) remained a significant independent predictor of an unsuccessful bridge. Short-term continuous-flow VADs can successfully bridge adult patients with mortality around 50%. Preimplant renal insufficiency or dialysis is correlated with an unsuccessful bridge in our patient population, likely reflecting the severity of illness preimplant. Further studies are required to determine whether this factor remains significant in a larger patient population.