Predicting Stroke For Pediatric Patients Supported With Ventricular Assist Devices:A PEDIMACS Report.

BACKGROUND: PEDIMACS provides detailed understanding on pediatric patients supported with ventricular assist devices (VADs). We sought to identify important variables affecting the incidence of stroke in pediatric VADs. METHODS: Between 2012-2022, 1,463 devices in 1,219 patients were reported to PEDIMACS s from 40 Centers in patients<19yrs at their first VAD implantation. Multiphase parametric hazard modeling was used to identify risk factors for stroke among all device types. RESULTS: Of the 1,219 patients, the most common devices were implantable continuous (472 [39%]), followed by paracorporeal pulsatile (342 [28%]), paracorporeal continuous (327 [27%]). Overall freedom from stroke at 6 months was higher in the recent era (2012-2016; 80.2% [77.1%-82.9%] vs 2017-2023; 87.9% [86.2%-89.4%], p=0.009). Implantable Continuous had the highest freedom from stroke at 3 (92.7% [91.1%-93.9%]) and 6 (91.1% [89.3%-92.6%]) months, followed by Paracorporeal Pulsatile (87.0% [84.8%-88.9%] and 82.8% [79.8%-85.5%]), and Paracoporeal Continuous (76.0% [71.8%-79.5%] and 69.5% [63.4%-74.8%]). Parametric modeling identified risk factors for stoke early post implant and later. Overall, and particularly for Paracorporal Pulsatile devices, early stroke risk has decreased in the most recent era (HR 5.01). Among Implantable Continuous devices, cardiogenic shock was the major risk factor. For patients<10kg, early hazard was only seen in previous era. For congentail patients, early hazard was seen in non-implantable device use and use of ECMO. CONCLUSIONS: Overall stroke rate has decreased from 20% to 15% at 6 months, with particular improvement among PP devices. Risk factor analyses offer insights for identification of higher stroke risk subsets and further management refinements.

Modifiable risk factor reduction for pediatric ventricular assist devices and the influence of persistent modifiable risk factors at transplant.

OBJECTIVES: Ventricular assist devices (VADs) are associated with a mortality benefit in children. Database-driven analyses have associated VADs with reduction of modifiable risk factors (MRFs), but validation with institutional data is required. The authors studied MRF reduction on VAD and the influence of persistent MRFs on survival after heart transplant. METHODS: All patients at the authors' institution requiring a VAD at transplant (2011-2022) were retrospectively identified. MRFs included renal dysfunction (estimated glomerular filtration rate <60 mL/min/1.73 m2), hepatic dysfunction (total bilirubin ≥1.2 mg/dL), total parenteral nutrition dependence, sedatives, paralytics, inotropes, and mechanical ventilation. RESULTS: Thirty-nine patients were identified. At time of VAD implantation, 18 patients had ≥3 MRFs, 21 had 1 to 2 MRFs, and 0 had 0 MRFs. At time of transplant, 6 patients had ≥3 MRFs, 17 had 1 to 2 MRFs, and 16 had 0 MRFs. Hospital mortality occurred in 50% (3 out of 6) patients with ≥3 MRFs at transplant vs 0% of patients with 1 to 2 and 0 MRFs (P = .01 for ≥3 vs 1-2 and 0 MRFs). MRFs independently associated with hospital mortality included paralytics (1.76 [range, 1.32-2.30]), ventilator (1.59 [range, 1.28-1.97]), total parenteral nutrition dependence (1.49 [range, 1.07-2.07]), and renal dysfunction (1.31 [range, 1.02-1.67]). Two late mortalities occurred (3.6 and 5.7 y), both in patients with 1 to 2 MRFs at transplant. Overall posttransplant survival was significantly worse for ≥3 versus 0 MRFs (P = .006) but comparable between other cohorts (P > .1). CONCLUSIONS: VADs are associated with MRF reduction in children, yet those with persistent MRFs at transplant experience a high burden of mortality. Transplanting VAD patients with ≥3 MRFs may not be prudent. Time should be given on VAD support to achieve aggressive pre-transplant optimization of MRFs.

Outcomes after initial heart failure consultation in Fontan patients.

BACKGROUND: Patients with Fontan failure are high-risk candidates for heart transplantation and other advanced therapies. Understanding the outcomes following initial heart failure consultation can help define appropriate timing of referral for advanced heart failure care. METHODS: This is a survey study of heart failure providers seeing any Fontan patient for initial heart failure care. Part 1 of the survey captured data on clinical characteristics at the time of heart failure consultation, and Part 2, completed 30 days later, captured outcomes (death, transplant evaluation outcome, and other interventions). Patients were classified as "too late" (death or declined for transplant due to being too sick) and/or "care escalation" (ventricular assist device implanted, inotrope initiated, and/or listed for transplant), within 30 days. "Late referral" was defined as those referred too late and/or had care escalation. RESULTS: Between 7/2020 and 7/2022, 77 Fontan patients (52% inpatient) had an initial heart failure consultation. Ten per cent were referred too late (6 were too sick for heart transplantation with one subsequent death, and two others died without heart transplantation evaluation, within 30 days), and 36% had care escalation (21 listed ± 5 ventricular assist device implanted ± 6 inotrope initiated). Overall, 42% were late referrals. Heart failure consultation < 1 year after Fontan surgery was strongly associated with late referral (OR 6.2, 95% CI 1.8-21.5, p=0.004). CONCLUSIONS: Over 40% of Fontan patients seen for an initial heart failure consultation were late referrals, with 10% dying or being declined for transplant within a month of consultation. Earlier referral, particularly for those with heart failure soon after Fontan surgery, should be encouraged.

Survival in Pediatric Patients With Ventricular Assist Devices: A Special Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs) Report.

BACKGROUND: The Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs) provides detailed understanding on pediatric patients supported with ventricular assist devices (VADs). We sought to identify important variables affecting mortality in pediatric VADs. METHODS: Patients aged <19 years, from 2012 to 2021, were included. Survival analyses were performed using Kaplan-Meier. Parametric hazard modeling was used to identify risk factors for death. RESULTS: Of the 1109 patients, the most common devices were implantable continuous (IC, 448 [40%]), followed by paracorporeal pulsatile (PP, 306 [28%]), paracorporeal continuous (PC, 293 [26%]), and percutaneous (58 [5%]). Patients with percutaneous device, infants, congenital heart disease, biventricular support, and Interagency Registry for Mechanically Assisted Circulatory Support profile 1 had worse overall survival at 6 months. Positive outcome was 83% at 6 months. Consistent with their cohort composition, device type positive outcomes at 6 months were IC, 92%; PP, 84%; and PC, 69%. Parametric hazard modeling for overall survival showed an early hazard for death with biventricular support, congenital heart disease (CHD), intubation before implantation, PC device, and renal impairment, whereas a constant hazard was associated with ascites. For patients <10 kg, parametric modeling showed an early hazard for CHD, intubation, and renal impairment. Modeling in CHD patients showed an early hazard for biventricular support, renal impairment, and use of PC/PP devices. CONCLUSIONS: This multivariable analysis of the complete Pedimacs database demonstrates that illness at VAD implantation, diagnosis, and strategy of support affect survival and differ by device type. We hope this is the first step in creating a predictive tool to help providers and families have informed expectations.

In the era of outpatient ventricular assist devices, is it time to reconsider the practice of bridging older children to transplant on outpatient inotropes?

OBJECTIVE: Ventricular assist devices (VADs) and inotropes are feasible modalities to bridge children to heart transplant (HT) in outpatient settings. However, it is unclear which modality yields superior clinical status at HT and posttransplant survival. METHODS: The United Network for Organ Sharing was used to identify patients aged 18 years or younger, weighing >25 kg, from 2012 to 2022 who were outpatients at HT (n = 835). Patients were grouped by bridging modality at HT: VAD (n = 235 [28%]), inotropes (n = 176 [21%]), or neither (no support) (n = 424 [50%]). RESULTS: VAD patients were of similar age (P = .260) but heavier (P = .007) and more likely to have dilated cardiomyopathy (P < .001) than their inotrope counterparts. VAD patients had similar clinical status at HT but superior functional status (performance scale >70%) (59% vs 31%) (P < .001). Overall posttransplant survival in VAD patients (1-year and 5-year survival, 97% and 88%, respectively) was comparable to patients with no support (93% and 87%, respectively) (P = .090) and those on inotropes (98% and 83%, respectively) (P = .089). One-year conditional survival was superior for VAD vs inotrope (2-year and 6-year survival, 96% and 91%, respectively vs 97% and 79%, respectively) (P = .030) and 5-year conditional survival for VAD patients was superior to inotrope (7-year and 10-year survival, 100% and 100%, respectively vs 100% and 88%, respectively) (P = .022) and no support (100% and 83%, respectively) (P = .011). CONCLUSIONS: Consistent with prior studies, short-term outcomes for pediatric patients bridged to HT in the outpatient setting with VAD or inotropes is excellent. However, compared with outpatients bridged to HT on inotropes, outpatient VAD support allowed for better functional status at HT and superior late posttransplant survival.

Heart transplant offers are less likely to be accepted on weekends, holidays, and conferences.

BACKGROUND: The existence of a "weekend effect" in heart transplantation (HTx) is understudied. The present study sought to determine whether the odds of (HTx) offer acceptance differed for adult and pediatric candidates depending upon the day on which the offer occurred. METHODS: United Network for Organ Sharing data were used to identify all HTx offers to adult (listing age ≥18) and pediatric candidates from 2000-2019. Odds of offer acceptance were studied, comparing weekends, holidays, and conferences (Society of Thoracic Surgeons [STS], American Association for Thoracic Surgery [AATS], International Society for Heart and Lung Transplantation [ISHLT]) to "baseline" (all other days). Multivariable binary logistic regression analyses were performed to determine independent predictors of offer nonacceptance, controlling for the impacts of program transplant volume, region, and candidate characteristics. RESULTS: A total of 323,953 offers occurred - 298,405 to adults and 25,548 to pediatric candidates. Clinically significant differences did not exist in donor or candidate characteristics between baseline or other events. The number of offers per day was stable throughout the year for both adults (p = 0.191) and pediatrics (p = 0.976). In adults, independently lower odds of acceptance existed on weekends (OR 0.88 [95% CI 0.84-0.92]), conferences in aggregate (0.86 [0.77-0.95]), and holidays in aggregate (0.81 [0.72-0.91]). In children, independently lower odds of acceptance were seen on weekends (0.88 [0.79-0.98]), during STS (0.46 [0.25-0.83], and during Christmas (0.32 [0.14-0.76]). CONCLUSIONS: The day on which a HTx offer occurs significantly impacts its likelihood of acceptance. Further work can determine the impacts of human behavior or resource distribution, but knowledge of this phenomenon can inform efforts to ensure ideal organ allocation throughout the year.

Global best practices consensus: Long-term management of patients with hybrid centrifugal flow left ventricular assist device support.

OBJECTIVES: Six months after withdrawal of the HeartWare HVAD System (HVAD; Medtronic) from sale, approximately 4000 patients continue ongoing support with this device. In light of the diminishing experience, this global consensus document summarizes key management recommendations. METHODS: International experts with experience in the management of patients with ongoing HVAD support were invited to summarize key aspects of patient and pump management and highlight differences in the current HeartMate 3 (Abbott Laboratories) ventricular assist device. Clinicians from high-implanting HVAD sites reviewed current literature and reported experience to generate a consensus statement. RESULTS: Specific guidelines to assist in the management of ongoing HVAD patients are developed. Key management protocols and helpful techniques developed from experienced clinicians are combined into a short guideline document. As experience with HeartMate 3 increases, key differences in approach to management are highlighted, where appropriate. CONCLUSIONS: With decreasing worldwide experience in the ongoing management of HVAD-supported patients, this consensus guideline provides a summary of best practice techniques from international centers. Differences in HeartMate 3 management are highlighted.

HVAD to HeartMate 3 left ventricular assist device exchange: Best practices recommendations.

The HeartWare HVAD System (Medtronic) is a durable implantable left ventricular assist device that has been implanted in approximately 20,000 patients worldwide for bridge to transplant and destination therapy indications. In December 2020, Medtronic issued an Urgent Medical Device Communication informing clinicians of a critical device malfunction in which the HVAD may experience a delay or failure to restart after elective or accidental discontinuation of pump operation. Moreover, evolving retrospective comparative effectiveness studies of patients supported with the HVAD demonstrated a significantly higher risk of stroke and all-cause mortality when compared with a newer generation of a commercially available durable left ventricular assist device. Considering the totality of this new information on HVAD performance and the availability of an alternate commercially available device, Medtronic halted the sale and distribution of the HVAD System in June 2021. The decision to remove the HVAD from commercial distribution now requires the use of the HeartMate 3 left ventricular assist system (Abbott, Inc) if a patient previously implanted with an HVAD requires a pump exchange. The goal of this document is to review important differences in the design of the HVAD and HeartMate 3 that are relevant to the medical management of patients supported with these devices, and to assess the technical aspects of an HVAD-to-HeartMate 3 exchange. This document provides the best available evidence that supports best practices. (J Thorac Cardiovasc Surg 2022;-:1-8).

HVAD to HeartMate 3 left ventricular assist device exchange: Best practices recommendations.

The HeartWare HVAD System (Medtronic) is a durable implantable left ventricular assist device that has been implanted in approximately 20,000 patients worldwide for bridge to transplant and destination therapy indications. In December 2020, Medtronic issued an Urgent Medical Device Communication informing clinicians of a critical device malfunction in which the HVAD may experience a delay or failure to restart after elective or accidental discontinuation of pump operation. Moreover, evolving retrospective comparative effectiveness studies of patients supported with the HVAD demonstrated a significantly higher risk of stroke and all-cause mortality when compared with a newer generation of a commercially available durable left ventricular assist device. Considering the totality of this new information on HVAD performance and the availability of an alternate commercially available device, Medtronic halted the sale and distribution of the HVAD System in June 2021. The decision to remove the HVAD from commercial distribution now requires the use of the HeartMate 3 left ventricular assist system (Abbott, Inc) if a patient previously implanted with an HVAD requires a pump exchange. The goal of this document is to review important differences in the design of the HVAD and HeartMate 3 that are relevant to the medical management of patients supported with these devices, and to assess the technical aspects of an HVAD-to-HeartMate 3 exchange. This document provides the best available evidence that supports best practices.

HVAD to HeartMate 3 Left Ventricular Assist Device Exchange: Best Practices Recommendations.

The HeartWare HVAD System (Medtronic) is a durable implantable left ventricular assist device that has been implanted in approximately 20,000 patients worldwide for bridge to transplant and destination therapy indications. In December 2020, Medtronic issued an Urgent Medical Device Communication informing clinicians of a critical device malfunction in which the HVAD may experience a delay or failure to restart after elective or accidental discontinuation of pump operation. Moreover, evolving retrospective comparative effectiveness studies of patients supported with the HVAD demonstrated a significantly higher risk of stroke and all-cause mortality when compared with a newer generation of a commercially available durable left ventricular assist device. Considering the totality of this new information on HVAD performance and the availability of an alternate commercially available device, Medtronic halted the sale and distribution of the HVAD System in June 2021. The decision to remove the HVAD from commercial distribution now requires the use of the HeartMate 3 left ventricular assist system (Abbott, Inc) if a patient previously implanted with an HVAD requires a pump exchange. The goal of this document is to review important differences in the design of the HVAD and HeartMate 3 that are relevant to the medical management of patients supported with these devices, and to assess the technical aspects of an HVAD-to-HeartMate 3 exchange. This document provides the best available evidence that supports best practices.

Developing an adolescent and adult Fontan Management Programme.

Patients with single-ventricle CHD undergo a series of palliative surgeries that culminate in the Fontan procedure. While the Fontan procedure allows most patients to survive to adulthood, the Fontan circulation can eventually lead to multiple cardiac complications and multi-organ dysfunction. Care for adolescents and adults with a Fontan circulation has begun to transition from a primarily cardiac-focused model to care models, which are designed to monitor multiple organ systems, and using clues from this screening, identify patients who are at risk for adverse outcomes. The complexity of care required for these patients led our centre to develop a multidisciplinary Fontan Management Programme with the primary goals of earlier detection and treatment of complications through the development of a cohesive network of diverse medical subspecialists with Fontan expertise.

Transplantation and Arch Repair in Fontan 3 Years After HeartMate 3: Technical Considerations.

We previously reported the first successful implantation of the HeartMate 3 (Abbott Laboratories) in a Fontan patient. We now report his successful transplantation after 1104 days of support, the longest reported bridge to transplant of a Fontan patient. We describe our operative technique complicated by not only the Fontan anatomy and ventricular assist device but also by a >10-cm ascending and aortic arch aneurysm. Additionally the posttransplant hemodynamics of this patient appeared to demonstrate that effective ventricular assist device support may induce reversal of chronic effects of the failing Fontan circulation, which in this case was the elimination of his aortopulmonary collateral burden.

Relation of Liver Volume to Adverse Cardiovascular Events in Adolescents and Adults With Fontan Circulation.

Elevated central venous pressure in those with Fontan circulation causes liver congestion and hepatomegaly. We assessed if liver volume by magnetic resonance imaging (MRI) is associated with adverse cardiovascular outcomes. Retrospective study of 122 patients with Fontan circulation who were >10 years old and had a liver MRI with magnetic resonance elastography. Liver volume (ml) was measured by manual segmentation from axial T2-weighted images and was indexed to body surface area. The composite outcome included death, heart transplant, ventricular assist device placement, or nonelective cardiovascular hospitalization. The median age at the time of MRI was 18.9 (interquartile range 15.8 to 25.9) years, and 47% of the patients were women. The mean indexed liver volume was 1,133 ± 180 ml/m2. Indexed liver volume was not significantly associated with age, years since Fontan, or with liver stiffness (r = 0.15, p = 0.10), but was positively correlated with Fontan pressure (r = 0.32, p = 0.002). Over a median follow-up of 2.1 (0.8 to 4.2) years, 32 patients (26%) experienced the composite outcome. Higher indexed liver volume was associated with a greater hazard for the composite outcome (hazard ratio per 1 SD increase = 1.74, 95% confidence interval 1.27 to 2.35, p = 0.0004) but increased liver stiffness was not significantly associated with the composite outcome (hazard ratio per 1 SD increase 1.44, 95% confidence interval 0.90 to 2.21, p = 0.11). In conclusion, greater liver volume indexed to body surface area is associated with unfavorable hemodynamics and adverse outcomes in patients with Fontan circulation. Liver volume may be a useful, simple imaging biomarker in adolescents and adults with Fontan circulation.

Ventricular Assist Device Therapy in the Fontan Circulation.

The number of Fontan patients with circulatory failure and systolic dysfunction is growing rapidly. The last decade has demonstrated that ventricular assist device (VAD) is an effective therapy in properly selected patients. Herein, we discuss the current approach to patient selection, implantation, and patient management.

Fourth Annual Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs) Report.

BACKGROUND: The Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs), originally a National Institutes of Health-sponsored U.S. database, provides a platform to understand the population of children supported with ventricular assist devices (VADs) during this time of increasing numbers, new devices, expanding indications, and improved outcomes. METHODS: Between September 19, 2012, and December 31, 2019, 44 hospitals implanted 1031 devices in 856 patients under 19 years of age. RESULTS: Overall, diagnosis was cardiomyopathy in 497 (58%) patients, congenital heart disease (CHD) in 216 (25%), myocarditis in 85 (10%), and other in 58 (7%). Positive outcome (alive on device or bridge to transplantation and recovery) occurred in 82% at 6 months. The patient cohort for implantable continuous (IC) pumps (n = 365) (age 13.2 ± 3.9 years, 18% Interagency Registry for Mechanically Assisted Circulatory Support [Intermacs] profile 1, 23% intubated at implantation, 16% with CHD) was significantly different from the paracorporeal continuous (PC) pump cohort (n = 212) (age 3.6 ± 4.9 years, 46% Intermacs profile 1, 81% intubated, 42% CHD) and the paracorporeal pulsatile (PP) pump cohort (n = 230) (age 2.7 ± 3.5 years, 31% Intermacs profile 1, 76% intubated, 26% CHD). Consistent with their cohort composition, positive outcomes at 6 months based on device type were the following: IC, 92%; PC, 68%; and PP, 81%. The incidence of cerebrovascular accidents in the IC, PC, and PP cohorts was 7%, 14%, and 15%, respectively. CONCLUSIONS: IC VADs, the most common VAD type placed in children, are associated with improved outcomes compared with PP and PC devices, though PP and PC devices are limited to supporting our most challenging patients. Noteworthy, the incidence of cerebrovascular accidents for pediatric VADs has significantly decreased and is now 11% overall. This report demonstrates again that although often attributed to age, size, or device type, much of the burden in mortality and adverse events is correlated to the patient's overall state at VAD implantation.

The total artificial heart in pediatrics: outcomes in an evolving field.

BACKGROUND: The use of the SynCardia temporary total artificial heart (TAH-t) in adults has increased with time. The development of the smaller, 50 cc TAH-t has expanded the potential applications of the device in children. We sought to describe the evolving use of the TAH-t over time and describe outcomes in the current era. METHODS: The SynCardia database was queried to identify all pediatric patients ≤18 years of age implanted with the device between December 1985 and October 2019. Patient demographics, clinical outcome and support characteristics collected. RESULTS: Fifty-one children were supported, 36 with the 70 cc TAH-t and 15 with the 50 cc TAH-t with a total support time of 6,243 days. The number of implants has increased with time (19 between 2015 and 2019). A total of 13 patients have been converted to Freedom Driver support, seven 50 cc TAH-t and six 70 cc TAH-t. The majority of implants in the last 5 years (15/19, 79%) have been with the 50 cc TAH-t. The most common diagnosis was dilated cardiomyopathy [24 (47%)] and the average age at the time of implant was 16±2 years old. Overall survival for the patient cohort was 71%. CONCLUSIONS: The use of the SynCardia TAH-t to support children with end-stage heart failure has increased over time. Clinical outcomes with both the 50 cc and 70 cc TAH-t are similar to reported outcomes in adults who require TAH-t or other methods of biventricular support.

The reality of limping to pediatric heart transplantation.

OBJECTIVE: Improvements in surgical technique, critical care, and early repair for congenital heart disease (CHD) have led to improved outcomes with heart transplantation, often used as a salvage procedure after failed palliation, especially in infants. These patients, however, often have several risk factors for poor posttransplant survival. We aimed to identify the reality of survival after heart transplantation in patients "limping to transplant" with common risk factors. METHODS: All heart transplant recipients younger than 18 years were identified from the UNOS data set from 2000 to 2017. Modifiable risk factors (MRFs) of mechanical ventilation, renal dysfunction, and liver dysfunction at transplant and nonmodifiable risk factors of infancy at listing or CHD were examined. One-year posttransplant survival was analyzed with logistic regression. RESULTS: Of 4101 transplants, 1459 patients (36%) had 1 or more MRFs. There was a decrease in 1-year survival with additional MRFs up to a 9.1-times increased risk of death in an infant with CHD. A noninfant without CHD and no MRFs had a 95% 1-year survival, in contrast to an intubated patient with CHD without other end-organ dysfunction, who had 1-year survival of 76%, which decreased to 58% if they were an infant and also had renal dysfunction. CONCLUSIONS: Patients "limping to transplant" with multiple risk factors demonstrates decreasing early survival relative to those without other end-organ dysfunction. It is imperative that we have transparent discussions about expected outcomes with these families and identify ways to optimize patients' conditions through other supportive avenues to improve posttransplant outcomes.

Profound Iron Deficiency Anemia and Irreversible Dilated Cardiomyopathy in a Child.

Iron deficiency anemia has been associated with a secondary and potentially reversible cardiomyopathy. The pathophysiologic paradigm has been that the hematologic disease begets cardiac dysfunction. There may be, however, a point at which myocardial injury is irreversible in susceptible individuals. We present the case of a 4-year-old, developmentally normal, child who presented with iron deficiency anemia and a dilated cardiomyopathy with congestive heart failure. Despite appropriate correction of the anemia, the patient developed decompensated heart failure requiring milrinone therapy and eventual heart transplantation. This report will alert clinicians to the potential for irreversible adverse cardiac remodeling and the importance of close pediatric cardiology consultation and serial assessment in order to implement appropriate heart failure therapy.