Mechanical Circulatory Support In Children Research Articles

Revived Role of Pulmonary Artery Band in Management of Heart Failure in Pediatric Dilated Cardiomyopathy.

Lack of appropriate durable Ventricular Assist Devices (VADs) that can be managed at home for very young children, and long wait times for transplant have led to search for alternate easily reproducible therapies. In the past decade or more, pulmonary artery banding (PAB), as a new indication of an old technology, has been gradually carried out worldwide as an alternative to mechanical circulatory support in children with end-stage left ventricular dilated cardiomyopathy (DCM) complicated with heart failure(HF), and has achieved encouraging early and mid-term outcomes. Technically, PAB is simple, safe, and effective. This is a promising therapeutic strategy, especially in developing countries where heart transplantation is difficult to implement. As a transition before transplantation, and even a potential treatment, PAB brings more options and hope for children with heart failure who are waiting for transplantation and are refractory to drug therapy. This article reviews the past and current situation, the mechanism, the surgical timing, and application prospect of PAB in the treatment of DCM complicated with heart failure.

Critical coarctation of the aorta in newborn - A case presentation

Background: Heart defects are the most popular congenital disease noticed among infants. Aortic Coarctation (CoA) forms 5 - 10 % of congenital heart diseases. The heart defect consist on aortic coarctation between inlet of the left subclavian artery and origin of the arterial ligament. In the during neonatal and early infantile period, in case of delayed diagnosis, it may lead to acute heart failure and the death of the child. 
 Case report: A female infant born at 37 weeks of gestation, by caesarean section, in good condition, was admitted to the Neonatal Department. There was a suspicion of CoA in the fetus in the pregnancy history. The Echocardiography showed a narrowing of the carpal tunel, prostin was included in the treatment. In the second day of life, the child was transferred to the Cardiology Department. Four-extremity blood pressures test showed higher values in the upper limbs than in the lower limbs. Echocardiography revealed hypoplasia of the aortic arch in the section below the exit of the second cephalic vessel with coarctation at the isthmus site. Laboratory tests showed a high level of pro-BNP. The control echocardiography showed the anatomy of the defect as before, an unobstructed wide arterial duct with a dominant R-L flow, a flow in the descending aorta of 2.7 m/s, with a coartable flow spectrum. The child was transported to the Department of Cardiac Surgery, Heart Transplantation and Mechanical Circulatory Support for Children in Zabrze for surgical treatment. 
 Conclusions: In neonates and infants with critical aortic stenosis, ensure the patency of the ductus arteriosus with continuous intravenous infusion of prostaglandin E1. Currently, echocardiography is the basic method in the diagnosis of aortic stenosis. 

Mechanical circulatory support in children

Mechanical circulatory support in children

Mechanical circulatory support in children: Strategies, challenges and future directions

IntroductionThe use of mechanical circulatory support (MCS) in the pediatric population has evolved significantly in the past 20 years, but its management still poses several challenges. We aim to describe patient characteristics, outcomes, and morbidity associated with different modalities of MCS, in a tertiary center. MethodsRetrospective analysis of data from all the children who underwent MCS between 2002 and 2018 at a pediatric cardiology unit. ResultsBetween 2002 and 2018, 22 devices were implanted in 20 patients. Patients were divided into three groups: Group A (n=11) extracorporeal membrane oxygenator (ECMO); Group B (n=8) pulsatile paracorporeal ventricular assist device (VAD) and group C (n=3) paracorporeal continuous flow VAD.The median age was similar in groups A and B (18 and 23 months, respectively), and higher in group C (13 years). ECMO patients were cannulated mainly as a bridge to recovery (post cardiotomy- 8) while group B and C patients were bridged to transplantation. The most frequent complications were bleeding (group A - 36%, group C - 66.6%) and thromboembolic events (group B - 50%, group C - 33.3%).As for outcomes, in group A the majority of patients (54.5%) were weaned and 27.3% died. Half of group B and all of group C patients underwent transplantation. ConclusionBleeding and thromboembolic events were the main complications observed. Group B showed the highest mortality, probably related to the low weight of the patients. Overall, outcomes and complications are related to the type of device and patient status and characteristics.

Recent Era Outcomes of Mechanical Circulatory Support in Children With Congenital Heart Disease as a Bridge to Heart Transplantation.

The objective of the study is to compare the clinical characteristics, risk factors, and overall survival (waitlist and posttransplant) outcomes in children with congenital heart disease (CHD) bridged to transplantation with either a ventricular assist device (VAD) versus extracorporeal membrane oxygenation (ECMO) versus no mechanical circulatory support (MCS) in the recent era. The study included 2,899 primary heart transplantations in patients <18 years with CHD between 2010 and 2019 from the United Network Organ Sharing database. Patients who had ECMO or VAD at listing or while listed were included, and their waitlist and posttransplant outcomes were compared with CHD patients who did not require MCS. Of all, 464 (16%) had ECMO and 200 (7%) VAD at the time of or during the listing. The VAD utilization increased over the last decade (4% in 2010 to 10% in 2019, p < 0.01). The 90 days post-MCS survival was better with VAD than ECMO (67 vs. 49%, p < 0.01). The transplantability rate at 90 days was decreased with younger age (odds ratio [OR], 0.91; 95% CI, 0.86-0.95), lower body mass index (BMI) (OR, 0.93; 95% CI, 0.89-0.98) and lower albumin <3g/dl (OR, 0.6; 95% CI, 0.53-0.7). The multivariate model predicted that lower BMI (OR, 1.12; 95% CI, 1.06-1.18), pretransplant ECMO (OR, 2.19; 95% CI, 1.39-3.45), and higher bilirubin (OR, 1.15; 95% CI, 0.97-1.36) decreased 1-year posttransplant survival. Patients transplanted with VAD had better 1-year survival than ECMO (88 vs. 70%, p = 0.01). Waiting list survival of children with CHD supported by VAD is better compared to ECMO. The 1-year posttransplantation outcome of CHD patients supported by VAD is similar to the no MCS patients and better than ECMO-supported patients. There is no significant difference in post-HT survival between patients transitioned from ECMO to VAD while listed and those with VAD-first.

Percutaneous Impella Device for Mechanical Circulatory Support in Children with Cardiogenic Shock: Long Term Outcomes

Use of temporary mechanical circulatory support (MCS) is an alternative to increase systemic blood flow avoiding the possible cardiotoxicity and long-term morbidity of inotropes and vasopressors. It is often the only option to achieve hemodynamic stability. Use of temporary MCS is increasing in frequency in children with evolution of new technologies. Recently, catheter deployed micro-axial percutaneous ventricular assist device (PC-VAD) has been approved for management of cardiogenic shock in adults. We present our experience and long-term outcomes associated with use of this device in a pediatric cardiac intensive care unit at a freestanding children's hospital. All patients treated for cardiogenic shock with PC-VAD alone between September 2014 and June 2019 were included in retrospective analysis. The device sizes used included CP device which provides up to 4.0 l/min of flow and 5.0 device which provides 5.0 l/min of flow. Demographic and support data were reviewed and reported using descriptive statistics. A total of 24 PC-VAD devices were implanted in 18 patients: CP (n=17), and 5.0 (n=7). Median patient age was 17 years (IQR 15,20), weight of 61 kg (IQR 54,75), and BSA of 1.72 m2(IQR 1.58,1.96). Median length of CP support was 5 days (IQR 4,7) and 5.0 was 12 days (IQR 11,22). The most common device related complications included site bleeding 9/24 (38%), ventricular arrhythmias 3/24 (17%) and extremity arterial thrombus 1/24 (4%), with no limb ischemia encountered. Acute renal failure requiring CRRT occurred in 5/18 (38%) patients. None of the patients sustained neurologic injury. Median ICU length of stay was 24 days (IQR 15,45) with median hospital length of stay of 35 days (26,80). The survival to ICU discharge was 89% (16/18) and survival to hospital discharge was 89% (16/18). Twelve out of eighteen (67%) patients were alive at one year. Temporary MCS for cardiogenic shock with PC-VAD shows favorable short and long-term outcomes in select pediatric patients. This type of circulatory support can be considered for management of older children with acute cardiogenic shock to achieve quicker hemodynamic stability, end-organ recovery and as a temporary bridge to recovery or clinical decision making. The risk profile in our population was low and only minor complications occurred during the treatment.

Mechanical circulatory support in children: past, present and future.

Rapid advances in the field of mechanical circulatory support (MCS) have dramatically changed the management of pediatric patients with heart failure. There is now emphasis on timely implantation of ventricular assist devices (VADs) to preserve or recover end-organ function, and increased focus on post-implant management to improve the stroke rate. Transplant waitlist mortality has significantly decreased in the era of VAD use. Devices approved for adults are being used off-label in children with excellent outcomes, allowing chronic therapy and discharge home to become part of pediatric VAD therapy.

Patient size parameters to guide use of the Impella device in pediatric patients.

To define patient and ventricular size parameters to guide Impella device (Abiomed, Inc., Danvers, MA) placement for mechanical circulatory support (MCS) in small pediatric patients (10-30 kg). There are few options for MCS in children, and there are no data on minimum patient size requirements for placement of the Impella 2.5 device. This was a multicenter study of echocardiographic and magnetic resonance imaging (MRI) derived dimensions of the left ventricle (LV) length and ascending aorta used to define minimum size parameters that are necessary for the placement of the Impella catheter. Data were collected from 44 cardiac MRIs conducted in healthy pediatric patients and 39 echocardiograms performed in pediatric patients with cardiomyopathy prior to surgical ventricular assist device (VAD) placement. The Impella 2.5 catheter is 7.5 cm from the pigtail to the aortic annulus marker, thus requiring an LV apical length of 7.5 cm to allow the device to function in an unconstrained fashion. In the cohort of patients undergoing consideration for VAD placement, a minimum LV length of 7.5 cm corresponded to a height of 122 cm, weight of 23 kg, and body surface area (BSA) of 0.89 m2 . In the MRI cohort, this corresponded to a height of 121 cm, weight of 23.9 kg, and BSA of 0.89 m2 . MCS with Impella devices is feasible in pediatric patients. This study defines anthropomorphic and anatomic measurements to guide providers in patient selection for MCS using the Impella devices.

Chronic Ovine Studies Demonstrate Low Thromboembolic Risk in the Penn State Infant Ventricular Assist Device.

Mechanical circulatory support for children under 6 years of age remains a challenge. This article describes the preclinical status and the results of recent animal testing with the Penn State Infant Left Ventricular Assist Device (VAD). The objectives have been to 1) demonstrate acceptably low thromboembolic risk to support Food and Drug Administration approval, 2) challenge the device by using minimal to no anticoagulation in order to identify any design or manufacturing weaknesses, and 3) improve our understanding of device thrombogenicity in the ovine animal model, using multicomponent measurements of the coagulation system and renal ischemia quantification, in order to better correlate animal results with human results.The Infant VAD was implanted as a left VAD (LVAD) in 18-29 kg lambs. Twelve LVAD and five surgical sham animals were electively terminated after approximately 30 or 60 days. Anticoagulation was by unfractionated heparin targeting thromboelastography R times of 2x normal (n = 6) or 1x normal (n = 6) resulting in negligible heparin activity as measured by anti-Xa assay (<0.1 IU/ml). Platelet inhibitors were not used.There were no clinically evident strokes or evidence of end organ dysfunction in any of the 12 electively terminated LVAD studies. The degree of renal ischemic lesions in device animals was not significantly different than that found in five surgical sham studies, demonstrating minimal device thromboembolism.In summary, these results in a challenging animal test protocol support the conclusion that the Penn State Infant VAD has a low thromboembolic risk and may allow lower levels of anticoagulation.

Platelet‐mapping assay for monitoring antiplatelet therapy during mechanical circulatory support in children: A retrospective observational study

Unlabelled Box IntroductionThe complex hemostatic changes associated with Berlin Heart (BH) implantation in children require a challenging antithrombotic treatment. The aim of this retrospective analysis was to evaluate the thromboelastography (TEG)‐platelet mapping (PM) assay to monitor antiplatelet therapy in children implanted with a BH. MethodsTEG‐PM was performed in 4 BH‐implanted patients receiving dipyridamole and aspirin, and 9 healthy volunteers. Patients’ antiplatelet therapy was adjusted to TEG‐PM results. Light transmission aggregometry (LTA) was also available for 2 of these patients. ResultsBetween 2009 and 2014, 4 BH‐implanted patients received a dual antiplatelet therapy monitored by TEG‐PM. In 2 patients, 18 of 34 tracings were atypical, because the maximum amplitude due to fibrin never stabilized, which made difficult antiplatelet therapy adjustment as recommended by BH's guidelines. To overcome this difficulty, TEG‐PM and LTA were next performed in parallel. However, both methods led to different decisions to adjust antiplatelet therapy in 57% of the cases. In order to better understand this atypical tracing, TEG‐PM was also performed in 9 volunteers and surprisingly 3 of them had the same atypical tracing. This atypical tracing was corrected by adding apyrase, suggesting that adenosine diphosphate (ADP) participates to spontaneous platelet activation in heparinized samples. In addition, we evidenced a high variability in the responses of TEG‐PM with ADP in volunteers. ConclusionsAntiplatelet therapy monitoring in BH‐implanted children remains challenging, as TEG‐PM is sensitive to several preanalytical and analytical conditions.

Monitoring and complications during neonatal/pediatric ECMO run

Extracorporeal membrane oxygenation (ECMO) is a commonly used form of mechanical circulatory support in children with congenital or acquired heart disease, and cardiac failure refractory to conventional medical treatments.1 The cardiac output is partially or completely provided by the ECMO machine. To assess how much support is needed at any given time, a constant balance of oxygen delivery and oxygen consumption is required. Permanent monitoring of flow, hemoglobin, arterial, and mixed venous saturations are key elements to provide the needed understanding and continuous guidance of body requirements, aiming at controlling and maintaining optimal management of the ECMO patient. Although ECMO is lifesaving in many circumstances, it bares challenges and certain risks of complications. Despite bioline-coated circuits, anticoagulation is required. Measurement of activated clotting time (ACT) and activated partial thromboplastin time (APTT) are both used to guide anticoagulation, but it is unclear which method is the best, and constant monitoring of the hemoglobin level allows the early detection of internal and external bleeding.2 For children, sedation and analgesia, most often in combination with paralysis, is unavoidable for a smooth ECMO run. On the other hand, with such treatment on board, it is almost impossible to assess the neurological status of the patient on ECMO. Different monitoring tools, such as cerebral near infrared spectroscopy (NIRS) and serial brain ultrasound studies, are used to estimate brain integrity and function, but further research is needed to show which methods are the most practical and useful to achieve a favorable outcome.3 Nutrition in critically ill children is known to be crucial but debated how to achieve as the gut perfusion can be impaired and therefore the risk of necrotizing enterocolitis (NEC) is increased. It is discussed if somatic perfusion by NIRS monitoring can help to avoid NEC.4 The kidney function is often impaired in these critically ill children and careful monitoring of kidney function and urine output leads the decision when to start which type of renal replacement therapy for renal clearance and/or fluid removal. Techniques available include peritoneal dialysis or continuous renal replacement therapy (CRRT) incorporated with the ECMO circuit. Medication dosing is under discussion in many centers as the circulatory volume is higher than normal. Adjustment of medication dosing could consequently be of great importance. Close monitoring of medications where toxic levels can be reached is crucial to avoid further damage to the patient's organ functions.

Berlin Heart EXCOR use in patients with congenital heart disease

Management of mechanical circulatory support in children with congenital heart disease (CHD) is challenging due to physiologic variations and anatomic limitations to device placement. In this study we examine the use of Berlin Heart EXCOR in CHD patients. CHD patients were identified from the EXCOR Pediatric Study data set (2007 to 2010). Mortality and serious adverse events were compared between CHD and non-CHD cohorts, and predictors of poor outcomes in the CHD cohort were identified. CHD was present in 29% (n = 59, 18 with 1-ventricle physiology) of all EXCOR patients (N = 204). Successful bridge (transplant or wean) was less likely in CHD patients compared with non-CHD patients (48% vs 80%; p < 0.01). Among CHD patients, no neonates, 25% of infants (30 days to 1 year) and 65% of children (>1 year) were successfully bridged. Pre-implant congenital heart surgery (CHS) and extracorporeal membrane oxygenation (ECMO) on the same admission occurred in 60% of children ≤1 year of age (83% of neonates, 50% of infants), with 8% survival. Regardless of age, patients who did not have CHS and ECMO had 61% survival. Smaller pump, pre-implant bilirubin >1.2 mg/dl and renal dysfunction were independently associated with mortality. End-organ function at implant reliably predicts adverse outcomes and should be considered when making implant decisions. EXCOR use in neonates and infants with CHD should be approached cautiously. If patients have undergone pre-implant CHS and ECMO, EXCOR support may not provide any survival benefit. EXCOR support in non-infants with CHD is challenging but can be consistently successful with appropriate patient selection.

Risk Factors for Cardiac Arrest or Mechanical Circulatory Support in Children with Fulminant Myocarditis.

In children with fulminant myocarditis (FM), we sought to describe presenting characteristics and clinical outcomes, and identify risk factors for cardiac arrest and mechanical circulatory support (MCS). A retrospective review of patients with FM admitted at our institution between January 1, 2004, and June 31, 2015, was performed. We compared characteristics and outcomes of FM patients who received cardiopulmonary resuscitation (CPR) and/or were placed on MCS (CPR/MCS group) to those who did not develop these outcomes (Control group). There were 28 patients who met criteria for FM. Median age was 1.2years (1day-17years). Recovery of myocardial function occurred in 13 patients (46%); 6 (21%) had chronic ventricular dysfunction, 6 (21%) underwent heart transplantation, and 3 (11%) died prior to hospital discharge (including one death following heart transplant). Of the 28 FM patients, 13 (46%) developed cardiac arrest (n=11) and/or received MCS (n=8). When compared to controls, patients in the CPR/MCS group had a higher peak b-type natriuretic peptide (BNP) levels (p=0.03) and peak inotropic scores (p=0.02). No significant differences were found between groups in demographics; chest radiograph, electrocardiogram, or echocardiogram findings; or initial laboratory values including BNP, troponin, C-reactive protein, lactate, and creatinine (p>0.05 for all). Children with FM are at high risk of cardiovascular collapse leading to the use of CPR or MCS. Aside from peak BNP levels and inotropic scores, the most presenting characteristics were not helpful for predicting these outcomes. FM patients should ideally receive care in centers that provide emergent MCS.

Asistencia mecánica circulatoria en el paciente pediátrico

Mechanical circulatory support (MCS) is the treatment of heart failure refractory to conventional pharmacological measures. MCS enables the blood to be pumped to the whole body while the heart recovers from the injury received, as well as the recovery of the secondary organs damaged by poor perfusion. In cases where the heart does not recover, it can give the patient to have more time on the waiting list for heart transplant, or can improve their quality and quantity of life in cases implanted as a final therapy.The use of MCS has become increasingly frequent in adults, as well as in the paediatric population, in recent years. In this section, a review is presented on the characteristics of MCS in paediatric patients with or without congenital heart disease. Firstly, a review of the indications is presented, as well as how to choose the most appropriate MCS for each patient. This is followed by an analysis of the short-term MCS in children, usually requiring lung support along with the heart, with an oxygenator in the circuit, which is given the name, extracorporeal circulation with membrane oxygenator. Thirdly, a look at the long-term MCS in paediatrics, which is almost exclusively reduced to the Berlin Heart implanted as a bridge to transplant. Finally, we present our experience with MCS, including both short and long-term follow up in paediatric patients, with the aim of contributing directly to improve the survival of our children.

HeartWare HVAD for Biventricular Support in Children and Adolescents: The Stanford Experience.

Despite increasing use of mechanical circulatory support in children, experience with biventricular device implantation remains limited. We describe our experience using the HeartWare HVAD to provide biventricular support to three patients and compare these patients with five patients supported with HeartWare left ventricular assist device (LVAD). At the end of the study period, all three biventricular assist device (BiVAD) patients had been transplanted and were alive. LVAD patients were out of bed and ambulating a median of 10.5 days postimplantation. The BiVAD patients were out of bed a median of 31 days postimplantation. Pediatric patients with both left ventricular and biventricular heart failure can be successfully bridged to transplantation with the HeartWare HVAD. Rapid improvement in functional status following HVAD implantation for isolated left ventricular support is seen. Patients supported with BiVAD also demonstrate functional recovery, albeit more modestly. In the absence of infection, systemic inflammatory response raises concern for inadequate support.

Short-term waitlist survival without mechanical circulatory support in children

Short-term waitlist survival without mechanical circulatory support in children

Mechanical Circulatory Support in Children

The field of pediatric mechanical circulatory support has undergone a significant evolution with the advent of devices designed for children and the implementation of new strategies for deployment. With the ongoing shortage of organs the demand for new devices specifically designed for children will only increase. This review discusses the evolution of mechanical circulatory support, available devices, and the implementation of new strategies for their deployment.

Outcomes of children implanted with ventricular assist devices in the United States: First analysis of the Pediatric Interagency Registry for Mechanical Circulatory Support (PediMACS)

Use of mechanical circulatory support in children has increased as more options have become available. A national account of the use of mechanical support in children and adolescents is essential to understanding outcomes, refining patient selection and improving quality of care. The Pediatric Interagency Registry for Mechanical Circulatory Support (PediMACS) is a National Heart, Lung, and Blood Institute-supported nationwide registry for temporary and durable ventricular assist device (VAD) use in patients <19 years of age. Between the launch in September 2012 and June 2015, 37 hospitals in the USA have enrolled patients. This first report of data from PediMACS analyzed pre-implant patient characteristics, survival using competing outcomes, and adverse events. Two hundred pediatric patients underwent 222 durable VAD implants. Patients' characteristics and outcomes of children supported with a temporary device (n = 41) were not analyzed in this report. The etiology of heart disease included 146 (73%) patients with cardiomyopathy and 35 (18%) with congenital heart disease. Thirty patients (15%) transitioned from extracorporeal membrane oxygenation (ECMO) and 76 (38%) had previous cardiac surgery. Most patients were Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) Level 1 (27%) or Level 2 (56%) at implant, with 13% at Level 3. Of the 200 patients supported with a durable device, 91 (46%) were supported with a pulsatile-flow device and 109 (55%) with a continuous-flow (CF) device. Patient age at first implant included 30 patients (15%) <1 year of age, 37 (19%) 1 to 5 years, 32 (16%) 6 to 10 years and 101 (51%) 10 to 18 years. Patients were supported with left ventricular assist device alone in 161 (81%), biventricular ventricular assist device in 29 (15%), right ventricular assist device in 4 (2.0%) and total artificial heart in 6 (3%), together comprising 783 months of follow-up. The 200 patients receiving primary durable devices had an actuarial survival of 81% at 6 months. Competing risk analysis at 6 months revealed that 58% of patients had been transplanted, 28% were alive on support, 14% had died and 0.6% recovered. In the overall cohort, there were 28 deaths. Reported serious adverse events included infection (n = 78), bleeding (n = 68), device malfunction (n = 79) and neurologic dysfunction (n = 52). PediMACS constitutes the largest single data repository with detailed information of pediatric patients implanted with VADs. The first PediMACS report reveals favorable outcomes despite the varying patient characteristics and pump types. However, the rate of adverse events remains high. With further data collection, analysis of patient risk factors critical to improving outcomes will be possible.

Pediatric mechanical circulatory support: available devices and outcomes as bridge-to-transplant therapy.

The use of mechanical circulatory support in children has increased dramatically over the current decade. A review of the pediatric ventricular assist device (VAD) literature is timely and relevant in order to improve outcomes and refine patient selection as new devices become available and current VADs are used in smaller patients. Outcomes of pediatric patients bridged to transplant with VAD therapy continue to improve. Patient selection in children continues to be complex as size and anatomy make decision-making unique from the adult practice. In addition, device selection and surgical planning are evolving in children. The use of temporary devices for long-term use is an example of an innovative application of current technology. Sensitization and adverse events are important issues that are necessary to understand in order to improve outcomes. The importance of a national registry to help monitor patient outcomes is critical to assessing this highly technological therapy. There are many implications of improving and expanding durable device use in children. VAD therapy is evolving as a standard of care as a bridge to transplant in children. Continued surveillance of outcomes is critical to improving patient selection and decreasing adverse events in children with advanced heart failure.

Abstract 15650: Nutritional Support With Medium Chain Fatty Acids During Extracorporeal Membrane Oxygenation in Infant Swine Model

Background: Extracorporeal membrane oxygenation (ECMO) is the most frequently used mechanical circulatory support in children with cardiopulmonary failure. Nutritional energy support as well as inotropic support is important to recover cardiac function during ECMO. Fatty acids (FAs) are major myocardial energy source for citric acid cycle (CAC). Medium-chain FAs (MCFAs) are easily uptaken into cell and mitochondria without membrane transporters. Our previous animal study suggested that MCFAs can potentially use for myocardial energy metabolism as the best accessible substrates during ECMO. Even-numbered MCFAs enter into CAC via acetyl-CoA, while odd-numbered MCFAs are anaplerotic for the CAC as propionyl-CoA in addition to acetyl-CoA. This study assessed whether odd- or even-numbered MCFAs product efficient energy during a short-term ECMO. Methods: Fifteen male Yorkshire pigs (26-45 days old) with 8-hour ECMO were received either normal saline, heptanoate (odd-numbered MCFA) or octanoate (even-numbered MCFA) at 2.3 μmol/kg body wt/min as MCFAs systemically during ECMO (n = 5 per group). The 13-Carbon ( 13 C) labeled substrates ([2- 13 C]lactate, [5,6,7- 13 C 3 ]heptanoate and [U- 13 C 6 ]leucine) as metabolic markers were infused into coronary artery for the final hour before left ventricular tissue extraction. Extracted left ventricular tissues were analyzed for the 13 C-labeled and absolute concentrations of metabolites by nuclear magnetic resonance and gas chromatography-mass spectrometry. Results: There were no adverse events in any groups during experiments. Octanoate produced markedly high citrate concentration, indicating the conjugation of CAC, and led to high [ATP]/[ADP] ratio compared with other groups (6.2 ± 0.6, 6.0 ± 0.6 and 7.8 ± 0.5 in normal saline, heptanoate and octanoate, P &lt; 0.05). Octanoate strongly increased the CAC metabolism through anaplerotic pathway from propionyl-CoA, but not heptanoate. Lactate oxidation and protein synthesis ratio from leucine were not different among 3 groups. Conclusions: Even-numbered MCFAs was superior energy source for CAC than odd-numbered MCFAs in normal heart supported with ECMO. These results support that nutritional therapy with even-numbered MCFAs facilitates weaning from ECMO.