Supporting pediatric patients with short-term continuous-flow devices

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1 Supporting pediatric patients with short-term continuous-flow devices Jennifer Conway, MD, a Mohammed Al-Aklabi, MD, b Don Granoski, RRT, c,d Sunjidatul Islam, MSc, a Lyndsey Ryerson, MD, c Vijay Anand, MD, c Gonzalo Guerra, MD, c Andrew S. Mackie, MD, a Ivan Rebeyka, MD, b and Holger Buchholz, MD b From the a Division of Cardiology, Division of Pediatric Cardiology, University of Alberta, Edmonton, Alberta, Canada; b Division of Pediatric Cardiac Surgery, Stollery Children s Hospital, Edmonton, Alberta, Canada; Divisions of c Division of Pediatric Critical Care, Cardiac Surgery; and the d Stollery Children s Hospital, Pediatric Cardiac Critical Care, University of Alberta, Edmonton, Alberta, Canada. KEYWORDS: short-term support; pediatric patients; continuous-flow; ventricular assist device; PediMag; CentriMag; RotaFlow BACKGROUND: Short-term continuous-flow ventricular assist devices (STCF-VADs) are increasingly being used in the pediatric population. However, little is known about the outcomes in patients supported with these devices. METHODS: All pediatric patients supported with a STCF-VAD, including the Thoratec PediMag or CentriMag, or the Maquet RotaFlow, between January 2005 and May 2014, were included in this retrospective single-center study. RESULTS: Twenty-seven patients (15 girls [56%]) underwent 33 STCF-VAD runs in 28 separate hospital admissions. The STCF-VAD was implanted 1 time in 23 patients (85%), 2 times in 2 patients (7%), and 3 times in 2 patients (7%). Implantation occurred most commonly in the context of congenital heart disease in 14 runs (42.2%), cardiomyopathy in 11 (33%), and after transplant in 6 (18%). The median age at implantation was 1.7 (interquartile range [IQR] 0.1, 4.1) years, and median weight was 8.9 kg (IQR 3.7, 18 kg). Patients were supported for a median duration of 12 days (IQR 6, 23 days) per run; the longest duration was 75 days. Before implantation, 15 runs (45%) were supported by extracorporeal membrane oxygenation (ECMO). After implantation, an oxygenator was required in 20 runs (61%) and continuous renal replacement therapy in 21 (64%). Overall, 7 runs (21%) resulted in weaning for recovery, 14 (42%) converted to a long-term VAD, 4 (12%) resulted in direct transplantation, 3 (9%) were converted to ECMO, and 5 (15%) runs resulted in death on the device or within 1 month after decannulation. The most common complication was bleeding requiring reoperation in 24% of runs. In addition, 18% of runs were associated with neurologic events and 15% with a culturepositive infection. Hospital discharge occurred in 19 of 28 STCF-VAD admissions (67%). In follow-up, with a median duration of 9.2 months (IQR 2.3, 38.3 months), 17 patients (63%) survived. CONCLUSIONS: STCF-VADs can successfully bridge most pediatric patients to recovery, long-term device, or transplant, with an acceptable complication profile. Although these devices are designed for short-term support, longer support is possible and may serve as an alternative approach to patients not suitable for the current long-term devices. J Heart Lung Transplant 2016;35: r 2016 International Society for Heart and Lung Transplantation. All rights reserved. Reprint requests: Jennifer Conway, MD, University of Alberta, Division of Pediatric Cardiology, St NW, Edmonton, AB T6G2B7, Canada. Telephone: þ address: jennifer.conway2@albertahealthservices.ca /$ - see front matter r 2016 International Society for Heart and Lung Transplantation. All rights reserved. There is growing interest in the use of short-term continuous-flow ventricular assist devices (STCF-VAD) in the pediatric population. These pumps, combined with various cannulation strategies, can be used in a left VAD

2 604 The Journal of Heart and Lung Transplantation, Vol 35, No 5, May 2016 configuration, with left atrial or left ventricular cannulation acting as the inflow and aortic cannulation as the outflow. Alternatively, right heart VAD (RVAD) support can be achieved with right atrial and pulmonary artery cannulation. Although this represents the classic configuration for these devices, alternative cannulation strategies may be required when implanting patients with congenital heart disease. Currently, there are a limited number of short-term devices that have been used in the pediatric population, with the CentriMag or PediMag (Thoratec Corporation) and the RotaFlow (Maquet) representing 3 possible options. The RotaFlow uses magnetic suspension around a single monopivot bearing, and the CentriMag is magnetically levitated, with no bearing or seals. 1 Although the 2 pumps are similar, the lack of bearings in the CentriMag has the added potential of less thrombus formation. 2 Although STCF-VAD configurations may improve outcomes compared with extracorporeal membrane oxygenation (ECMO) in certain populations of children, this is largely unproven. The published pediatric experience is limited to single case reports or small case series. 3 5 In pediatric patients, ECMO has traditionally been used for short-term mechanical support and durable VADs for longer-term support. The use of STCF-VADs may allow for evaluation of recovery, assessment of neurologic status, and better assessment of treatment options without the time constraints of ECMO. In addition, advantages of STCF- VADs compared with other forms of short-term support, such as ECMO, include the option of different cannulation strategies and the ability to connect the pumps to more secure cannulas such as those manufactured for the EXCOR (Berlin Heart). 6 This adaption allows for safe mobilization and rehabilitation in this patient population, which is difficult with ECMO. Despite these potential advantages, little information is available in the pediatric population with respect to complications and outcomes after STCF-VAD use. Therefore we sought to describe our single-center pediatric experience with the CentriMag and PediMag and the RotaFlow as STCF-VADs. Methods The local Research Ethics Board approved the study protocol, and the requirement for individual patient consent was waived. Patient population This was a retrospective study of all pediatric patients (aged 0 17 years) supported with the CentriMag/PediMag or RotaFlow who were cannulated in a VAD configuration (right ventriclepulmonary artery, left atrium/left ventricle aorta) from January 1, 2005, to May 30, 2014, at the Stollery Children s Hospital, Edmonton, Alberta, Canada. Patients were cannulated using bypass cannulas or Berlin Heart EXCOR cannulas, depending on the clinical situation and expected duration of therapy. Each trial of short-term device therapy was considered a separate event and was included as a separate VAD run. Patient demographic and clinical characteristics were collected. Outcome The primary outcome of this study was decannulation from the STCF-VAD due to transplantation, recovery, conversion to a longer-term VAD, and death or death within 1 month of weaning off the device. Complete follow-up data were available for all patients. Five types of VAD-related complications were explored in this cohort and included bleeding, neurologic events, infection, ischemic organ damage, and mechanical device failure. We defined significant bleeding as the requirement for reexploration for bleeding or hematoma. Neurologic events included intracranial bleeding or ischemic stroke diagnosed by computed tomography CT) scan. Infections were defined as the presence of an organism from the blood, urine, cannula site, or sputum with associated clinical symptoms. In the absence of a defined organism, antibiotic use alone was not considered as evidence of infection. We also sought to describe ischemic events in other organs, such as the gastrointestinal tract or spleen, diagnosed by imaging or pathologic specimen. Finally, mechanical device failure was defined as malfunction of one or more components rendering the system incapable of functioning and requiring a device exchange. This did not include exchanges for pump thrombosis or clots in the circuit. Statistical analysis Descriptive statistical methods were used. Continuous variables are described as median with interquartile range (IQR) due to nonnormality of the data, and absolute numbers are presented with proportions for categoric variables. The duration of support was calculated as the number of days between implant and removal of the device, regardless of the reason for decannulation. Patient management Device selection in our institution depends on the clinical situation and potential for recovery. For patients who acutely deteriorate, ECMO is first-line therapy, with conversion to a short- or longterm VAD within 5 to 10 days of ECMO initiation. Conversion to a short-term VAD usually occurs in the context of the potential for recovery, if further time is required for transplant assessment (e.g., neurologic assessment) or if renal replacement therapy or an oxygenator were needed in the system. If it was deemed a patient would move on to a long-term device or be bridged to transplant with a short-term device, a comprehensive transplant assessment did occur, including evaluation of neurologic function by clinical examination and imaging when deemed necessary. Patients were kept awake and as mobile as possible based on stability of the cannulas. Anti-coagulation with unfractionated heparin (UFH) was started within 12 to 24 hours of device implantation, depending on the degree of post-operative bleeding based on chest tube output. An acceptable chest tube output as a trigger for starting UFH was considered o 2 ml/kg/h. UFH was titrated to a target anti-xa level of 0.35 to 0.6 U/ml, with a goal activated clotting time range that correlated with the anti-xa target. Anti-coagulation goals and agents were adjusted individually depending on the circuit condition as well as on the patient s bleeding and thrombotic profile.

3 Conway et al. STCF-VAD Support in Pediatric Patients 605 Results Demographics and clinical outcomes From 2005 to 2014, 27 children (15 girls [56%]) were supported with a STCF-VAD with a total of 33 runs in 28 separate hospital admissions (Table 1), comprising 85% (n ¼ 23) with 1 run, 7% (n ¼ 2) experienced 2, and an additional 7% (n ¼ 2) were supported on three occasions. At the time of implant, the patients were a median age of 1.7 years (IQR 0.1, 4.1 years) with a median weight of 8.9 kg (IQR 3.7, 18 kg). The most common reason for implantation during the 33 runs was congenital heart disease in 14 (42%), followed by cardiomyopathy in 11 (33%) and post-heart transplantation in 6 (18%). At the time of implantation, 15 runs (45%) were preceded by ECMO. Of the 33 runs, ECMO was used before 5 for extracorporeal cardiopulmonary resuscitation, 4 for low cardiac output, 4 after cardiac surgery, and before 1 for acute respiratory distress syndrome associated with sepsis. ECMO duration before conversion to a STCF-VAD was a median of 6 days (IQR 1, 11 days), with a maximum duration of 17 days. Of the patients with congenital heart disease, there were 13 patients with 14 STCF-VAD runs. Ten patients had a biventricular circulation. This included 3 patients with transposition of the great arteries, 2 with anomalous left coronary artery from the pulmonary artery repair, and 2 with Ebstein anomaly. One patient had Shone complex, 1 neonate had biventricular outflow obstruction, and 1 child had a bicuspid aortic valve with endocarditis. All of the patients with Ebstein anomaly had an isolated RVAD; 2 of the patients were neonates. In addition, there were 3 patients with single-ventricle anatomy, including 2 children post-fontan, with one of them requiring 2 runs, and a neonate with right atrial isomerism, atrioventricular septal defect, and pulmonary stenosis. One of the patients with a Fontan required a total cardiectomy, with the details of the cannulation strategy previously reported, 7 whereas the other patient was cannulated from the left atrial appendage to the aorta. Five children were supported after heart transplantation, with 4 patients supported in the acute post-transplant period; 1 patient had 2 runs in longer-term follow-up for complications secondary to graft vasculopathy. In the 4 patients with acute ventricular failure immediately after transplant, 3 required an isolated RVAD and 1 a biventricular assist device (BiVAD). Of the 3 patients with acute RV failure, 2 were in the context of elevated pulmonary pressures. The patient with biventricular dysfunction had primary graft failure immediately after transplant, with no clear precipitating etiology. Fourteen (42%) of the implanted devices were LVADs, 4 (12%) were systemic devices for single-ventricle physiology, 8 (24%) were RVADs, and 7 (21%) were BiVADs. The pump types used for each run and duration of support is outlined in Table 2. The runs that required an RVAD were in the context of Ebstein anomaly in 2, early post-heart transplant in 3, and RV support after implantation of a longterm durable VAD in 3. Of the 33 runs, 14 (42%) occurred after cardiac surgery, with 10 of the runs (71%) in the context of congenital heart disease and 4 (29%) after heart transplant. Six of these Table 1 Demographic and Clinical Characteristics of Patients With Short-Term Continuous-Flow Ventricular Assist Device Implant Based on Implantation Strategy Site of implantation of VAD Variables a All patients Left and systemic ventricle Right ventricle Biventricle Patients (56) 5 (19) 7 (26) Total STCF-VAD runs Age at implant, years 1.7 (0.1, 4.1) 0.7 (0.1, 3.6) 1.4 (0.2, 10.8) 3.5 (0.6, 16.5) Weight at implant, kg 8.9 (3.7, 18.0) 7.2 (3.6, 14.8) 10.9 (3.8, 29.5) 14 (8.4, 41.0) Female sex 15 (56) 9 (60) 2 (40) 4 (57) VAD implantations, No (85) 13 (86) 4 (66) 6 (100) 2 2 (7) 1 (7) 1 (17) 3 2 (7) 1 (7) 1 (17) - Duration of support per run, days 12 (6, 23) 11.5 (7, 37) 12.5 (2, 28) 12 (9, 22) Diagnosis at implantation 33 Cardiomyopathy/myocarditis 11 (33) 5 (28) 3 (43) 3 (38) Congenital heart disease b 14 (42) 10 (56) 2 (29) 2 (25) Post-transplantation 6 (18) 2 (11) 1 (14) 3 (38) Other 2 (6) 1 (6) 1 (14) Pre-implant ECMO 15 (45) 8 (44) 2 (25) 5 (71) Oxygenator added to the circuit 20 (61) 9 (50) 5 (63) 6 (86) Renal replacement therapy 21 (64) 11 (61) 4 (50) 6 (86) ECMO, extracorporeal membrane oxygenator; STCF, short-term continuous-flow; VAD, ventricular assist device. a Continuous data are presented as the median and interquartile range (25th quartile, 75th quartile) and categoric data as number (%). b Congenital heart lesions (13 patients/14 runs): transposition of great arteries (n ¼ 3), anomalous left coronary artery from the pulmonary artery (n ¼ 2), Ebstein anomaly (n ¼ 2), Shone complex (n ¼ 1), bicuspid valve (n ¼ 1), biventricular outflow tract obstruction (n ¼ 1), Fontan (n ¼ 2), and right atrial isomerism with unbalanced atrioventricular septal defect (n ¼ 1).

4 606 Table 2 Number of Runs and Duration of Support by Type of Device The Journal of Heart and Lung Transplantation, Vol 35, No 5, May 2016 Duration of support Runs (N ¼ 33) Median (IQR) days Min Max days Type of device No. (%) CentriMag/PediMag 19 (58) 11 (6, 33) 2 75 RotaFlow 8 (24) 9 (3, 19.5) 1 37 CentriMag/PediMag and RotaFlow 6 (18) 20 (12, 33) 9 70 IQR, interquartile range (25 th,75 th quartile). implants (43%) occurred in the first 24 hours after surgery, and 1 patient with congenital heart disease had 2 runs after surgery. After implantation, 20 of the runs (61%) were associated with the need for an oxygenator, and continuous renal replacement therapy (CRRT) was added to the circuit in 21 (64%). Of the 20 patients requiring an oxygenator, 14 (70%) had been supported by ECMO before VAD implantation. Twenty-one percent of the runs did not require ECMO before implant or an oxygenator after. Of 33 VAD runs, 10 runs (30%) required the chest to be left open after implantation. There was no difference in deaths or complications between runs with an open vs closed chest (70% vs 61%, p ¼ 0.71). Patients were supported with a STCF-VAD for a median duration of 12 days (IQR 6, 23 days), with the longest run being 75 days. Fourteen runs (42%) resulted in conversion to a long-term VAD (Berlin Heart EXCOR, HeartWare HVAD, or Thoratec HeartMate II). Seven runs (21%) were weaned for recovery, and 4 runs (12%) resulted in direct transplant. Of the patients weaned from device, 6 weans occurred after cardiac surgery, 3 weans after surgery occurred in the first week after implant but beyond 72 hours, and the 3 additional weans after surgery occurred between 10 and 61 days after implant. Three runs (9%) required conversion to ECMO cannulation for additional cardiopulmonary support, and 5 runs (15%) ended in death on the device or within 1 month after decannulation (Table 3). The 3 patients converted to ECMO died during ECMO support. Conversion to ECMO occurred in 2 patients due to overwhelming sepsis with poor cardiac output and the third patient from loss of RVAD flow thought to be secondary to a pulmonary hypertensive crisis or clot in the pulmonary artery cannula. ECMO preceded 15 of the STCF-VAD runs, with 9 patients (60%) surviving to hospital discharge. For those runs that required ongoing or newly initiated renal replacement therapy after implantation, the survival was 62% (13 of 21). There were 13 VAD runs where patients were supported by ECMO before implant and after implant were on CRRT, and 8 of these children (62%) survived. The causes of in-hospital death varied and are outlined in Table 3, with multiorgan failure being the final common pathway in 66% of the patients. For those patients with congenital heart disease, 64% survived to hospital discharge. One of the 3 patients with single-ventricle physiology survived to transplant after conversion to a Berlin Heart EXCOR. Of the 4 patients supported acutely after heart transplantation, 2 of the 3 patients who required an isolated RVAD survived to hospital discharge. The remaining patient required a BiVAD and was supported to retransplantation but died of multiorgan failure after retransplantation. Sixty-seven percent (19 of 28) of all STCF-VAD hospital admissions led to hospital discharge, with a median total hospital length of stay in 27 patients of 116 days (range, days). The median length of stay in the intensive care unit (ICU) in 29 patients before discharge was 38.5 days (IQR 5, 101 days), with a median duration of 21 days (IQR 0, 243 days) on ventilatory support in 28 patients during their entire ICU stay. With a median follow-up duration of 9.2 months (IQR 2.3, 38.3 months), 63% (17 of 27) of all patients were alive. Device performance and complications There were no device-related mechanical failures. A number of patients required circuit changes or removal of a section of the circuit for evolving thrombus. Of the 33 runs, 15 (45%) were free from neurologic complications, bleeding, infection, or ischemic events. Eight runs required reexploration for bleeding early after surgery (median 4 days [IQR 0.5, 9.5 days]), with 75% of these patients on ECMO in the 24 hours before conversion to a VAD. Six runs were associated with a neurologic event, with 2 of the events being an ischemic stroke and the other 4 a sub-dural bleed. The median days from implantation of a device to a neurologic event was 12.5 days (IQR 4.75, days). Five of these patients survived to hospital discharge. Six runs were complicated by infection; 2 of these infections were a fungal septicemia. The interval after implant to an infection was a median of 14.5 days (IQR 5, days). An associated non-neurologic ischemic event occurred in 3 runs: 1 patient had a splenic infarct and gut ischemia, 1 patient required a colectomy for bowel ischemia, and 1 patient had an isolated splenic infarct. A comparison between the 2 devices was not performed due to the various combination of devices and the small numbers. Discussion Acute heart failure occurs in a number of different settings in pediatrics. STCF-VAD support permits time for decisions to be made about the potential for myocardial recovery and allows for a detailed assessment of end-organ function.

5 Conway et al. STCF-VAD Support in Pediatric Patients 607 Table 3 Cause of Death During Hospital Admission for Short-Term Continuous-Flow Ventricular Assist Device Run Patient Diagnosis Duration of ST-CF VAD support (days) Death on device a Cause of death Comments 1 HTx and RV failure 75 days pre-htx; 6 days post-htx Yes MOD post-htx CentriMag pre-htx for myocarditis and post-htx for RV failure 2 Allograft vasculopathy 37 No Ischemic bowel Converted to ECMO for sepsis before death 3 Primary HTx and BiV failure 6 No MOD post-second HTx On ST-CF VAD till re-htx, died after 2 nd HTx after support withdrawn 4 RAI, AVSD PS and BiV 68 Yes Heart failure One-way wean due to MOD dysfunction 5 Post-Fontan operation 2 runs: 10 days and 45 days Yes MOD Native heart excised due to intramyocardial hematoma 6 Transposition of the great arteries 7 Yes Renal failure, with severe uncontrollable fluid Therapy withdrawn 7 BiV outflow tract obstruction with LV dysfunction 8 Bicuspid aortic valve and endocarditis overload 4 No Died post-htx from MOD Was converted to ECMO pre-htx and received HTx from ECMO 22 Yes MOD 9 Neonatal Ebstein anomaly 2 No Sepsis with MOD Converted to ECMO before death AVSD, atrioventricular septal defect; BiV, biventricular; ECMO, extracorporeal membrane oxygenation; HTx, heart transplant; MOD, multiorgan dysfunction; PS, pulmonary stenosis; RAI, right atrial isomerism; RV, right ventricle; ST-CF, short-term continuous-flow; VAD, ventricular assist device. a Death on device or within 1 month of weaning. ECMO is another option for short-term support for acute cardiopulmonary failure, but survival to hospital discharge remains a challenge, with reports of 32% to 73% in single centers studies 8 13 and 40% to 50% for pediatric cardiac ECMO from the Extracorporeal Life Support Organization (ELSO) registry. 14 We have shown from our experience that STCF-VADs are able to support 67% of children to hospital discharge, with successful long-term outcomes. These results are similar to an analysis of the United Network Organ Sharing database that examined children bridged to transplant with a temporary assist device. Children in this study were supported for a median duration of support of 11 days, with 58% achieving transplant, 14% achieving recovery, and death occurring in 28%. 15 Although patient characteristics likely differ between children supported in the ECMO literature compared with those supported on ST-CF VADs, our results occurred in the context of a high-risk patient population with more than 50% of the children being supported by ECMO before STCF-VAD and most of them requiring CRRT or an oxygenator at some point after implantation. Because there are limited reports on ST-CF VADs in pediatrics, it is difficult for us to comment on the requirements for additional supportive measures, such as CRRT and oxygenators, in our patient population. It is possible that the use of oxygenators is higher than would be expected in our patient population. This occurred in 2 scenarios.the first was in patients transitioned from ECMO, where the goal was to wean the oxygenator during their time on support. The second scenario was the addition of an oxygenator to the circuit during support due to a complication such as pneumonia. STCF-VADs are marketed and approved for short-term use in the United States. However, there is a group of patients in whom long-term support may be provided, with our longest patient being supported for 75 days. Haj-Yahia et al 16 reported 4 adults with severe cardiogenic shock and associated end-organ dysfunction who underwent Thoratec CentriMag BiVAD implantation who were supported to transplant. The support duration was between 26 and 105 days, with a low complication profile. As part of the longterm strategy to preserve circuit integrity, they changed the circuit and pump every 4 to 6 weeks. 16 We do not perform routine circuit changes in patients supported for longer periods, but we have a low threshold for cutting out pieces of the circuit or changing the entire setup based on the development of clot or rising plasma free hemoglobin, an indicator of inadequate circuit mechanics. In addition to longer-term support, STCF-VADs, unlike ECMO, can provide isolated right heart support thereby decreasing the risk of ischemic stroke. In adults, RVAD placement has been predominantly reported after long-term LVAD implantation or cardiac transplant associated with acute right heart failure. 17 These studies have demonstrated a 50% to 60% chance of right heart recovery and subsequent decannulation. 17,18 In our series, 8 runs were isolated RVADs. Three of these runs occurred after heart transplant, with 2 of the 3 patients weaned from support and decannulated. Another 2 of runs occurred in the same patients with biventricular failure secondary to β-thalassemia major. The first was for ongoing right heart support after conversion to a long- term LVAD (Thoratec HeartMate II), and the second run occurred after the development of acute respiratory distress syndrome/pulmonary edema when an attempt was made to support the patient with a right-sided Berlin Heart EXCOR and a left sided Thoratec HeartMate II. 19 An additional patient had a right-sided

6 608 The Journal of Heart and Lung Transplantation, Vol 35, No 5, May 2016 RotaFlow combined with a left Berlin Heart after mitral valve repair for dilated cardiomyopathy. The last 2 patients were neonates with Ebstein anomaly with severe right-heart failure. In our series, 75% of patients supported with a RVAD survived to hospital discharge. One death occurred on RVAD support after transplant, and the second patient had neonatal Ebstein, requiring conversion to ECMO, and later died of sepsis and multiorgan failure. The most common complication in our series was bleeding requiring reoperation in 24% of the runs. In addition, 18% of the runs were associated with neurologic events and 15% with a culture-positive infection. These reported rates are less than those seen with long-term pulsatile VADs in children and are less than those on ECMO. Reports generated from the ELSO registry have suggested hemorrhagic complications occur in approximately 50% children supported with ECMO for cardiac reasons, with neurologic events ranging from 14% to 20%, depending on the patient population studied The 2 pumps used in this analysis were reliable, with no pump failures and rare development of clots in the pump. Most clots in our experience have occurred in the cannulas or circuit tubing, requiring cleaning, removal of a piece of circuit, or a circuit change. Because bleeding accounted for most of the complications in our cohort, reevaluation of the timing of initiation of anti-coagulation and the type of anticoagulation required for these devices in children requires further assessment. Study limitations This is one of the larger series of pediatric patients supported with an STCF-VAD, but there are a number of limitations inherent to the retrospective nature and small sample size. In addition, although this analysis concentrated on a few specific complications, it was not meant to imply that these are the only complications that may arise during support of these patients, and ongoing and careful monitoring is required. Conclusions STCF-VADs can successfully bridge pediatric patients to recovery, a long-term device, or transplant in most cases, with an acceptable complication rate. Although these devices are designed for short-term support, longer support is possible and may be an alternative support strategy for patients who are not suitable for the current long-term devices. Further studies are required to better understand the complication profile and the ideal management strategy, including anti-coagulation, for children supported with these pumps. Disclosure statement None of the authors has a financial relationship with a commercial entity that has an interest in the subject of the presented manuscript or other conflicts of interest to disclose. 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7 Conway et al. STCF-VAD Support in Pediatric Patients Paden ML, Rycus PT, Thiagarajan RR. Update and outcomes in extracorporeal life support. Semin Perinatol 2014;38: Werho D, Pasquali S, Yu S, et al. Stroke in pediatric cardiac surgical patients on extracorporeal membrane oxygenation: an analysis of the Extracorporeal. Life Support Organization database. J Am Coll Cardiol 2014;63(12 Suppl):A Polito A, Barrett CS, Wypij D, et al. Neurologic complications in neonates supported with extracorporeal membrane oxygenation. An analysis of ELSO registry data. Intensive Care Med 2013;39: Polito A, Barrett CS, Rycus PT, Favia I, Cogo PE, Thiagarajan RR. Neurologic injury in neonates with congenital heart disease during extracorporeal membrane oxygenation: an analysis of Extracorporeal Life Support Organization Registry data. ASAIO J 2015;61: Hervey-Jumper SL, Annich GM, Yancon AR, Garton HJ, Muraszko KM, Maher CO. Neurological complications of extracorporeal membrane oxygenation in children. J Neurosurg Pediatr 2011;7: