Cardiac Support Research Articles

Awake VA-ECMO in cardiogenic shock, single centre experiences

Abstract Funding Acknowledgements None. Background/Introduction "Awake" V-A ECMO when the patient is fully awake, breathing spontaneously, without deep sedation. Advantages of awake VA-ECMO include reduced sedative side effects, early active movements, reduced muscle mass loss, increased interaction with the family and medical staff, description of their symptoms, and more exact information than sedative patients so that early detection of complications. Purpose and Methods Present a series of 15 patients with cardiac support by awake VA-ECMO, techniques, parameters, complications, and treatment results. Results Enrolled in this study, including 15 patients: 04 NSTEMI (very high-risk PCI), 09 Myocarditis, 02 electrical storm; Age 53,2 ± 19,5. The local anesthesia, mild sedation when the patient is anxious; performed vascular access with DSA system. The duration from the patient's admission to ECMO was 3,8 ± 2,9 (day) and awake VA-ECMO 3,1 ± 2,5 (day) (min to max: 1 – 6). The CO of ECMO: 1,6 ± 1,2 (l/ph); 03 patients with continuous renal replacement therapy. A patient with acute thrombosis of the lower extremity had successful percutaneous thrombectomy; fifteen patients were successfully weaned from ECMO (100%), no patient death in 7 days, and 02 patient deaths in 30 days. Conclusion Awake VA-ECMO can be performed safety on the cardiac patient when waiting for recovery or management.

Impella vs Veno-arterial extracorporeal membrane oxygenation in cardiogenic shock: a systematic review and meta-analysis of propensity score matched studies

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Abiomed Singapore PTE. Ltd. Background/Introduction Cardiogenic shock is a life-threatening condition associated with multi-organ failure and death. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is well-established in the management of cardiogenic shock; however, mortality rates have remained relatively consistent over the past two decades. Impella is a transluminal microaxial ventricular assist device that improves haemodynamics by unloading the left ventricle and represents an alternative to VA-ECMO. No randomised controlled trials exist to date comparing Impella versus VA-ECMO given difficulties in recruiting patients due to the acute nature of the condition. Whilst a plethora of non-randomised, comparative studies have been published, many are confounded by underlying differences in baseline disease characteristics. Propensity score matched / adjusted studies may mitigate confounding by accounting for differences in important covariates that impact outcomes. Purpose The objective of this study was to conduct a systematic review and meta-analysis of propensity score matched / adjusted studies to assess the clinical outcomes of Impella versus VA-ECMO in cardiogenic shock patients. Methods A systematic review was undertaken to identify all comparative studies of Impella and VA-ECMO in cardiogenic shock which performed propensity score matching / adjustment of outcomes to account for important covariates. The study limitations were assessed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) approach. In-hospital/30-day survival and bleedings requiring transfusion were meta-analysed using the random effects method. Results Six propensity score matched / adjusted studies comparing Impella versus VA-ECMO in cardiogenic shock were included in the meta-analysis. A statistically significant difference in in-hospital/30-day mortality was detected between patients treated with Impella (39.6%) versus VA-ECMO (53.8%) (odds ratio [OR] 95% confidence interval [95% CI]: 0.57 [0.44, 0.74]; p<0.0001). Similarly, Impella (19.9%) was associated with statistically significantly fewer bleeding events requiring transfusion compared with VA-ECMO (28.8%) (OR=0.61 [0.46, 0.80]; p=0.0004). Conclusion(s) This systematic review identified no randomised controlled trials of Impella versus VA-ECMO. The meta-analysis of propensity matched observational trials, represents the highest level of evidence available to date, and suggests that Impella may be associated with increased survival rates and decreased bleeding. Randomised controlled trials are urgently needed to assess cardiac support modalities in cardiogenic shock.

Effect of COVID-19 Pandemic on Complications and Mortality in the Early Postoperative Period After Heart Transplantation

IntroductionThe coronavirus disease 2019 (COVID-19) outbreak directly impacted heart transplantation (HT) surgery activity. Reallocating resources and converting surgical intensive care units to COVID‐19 facilities led to reduced accessibility and quality of health care facilities to heart recipient patients. AimTo study the effect of the COVID-19 pandemic on heart transplantation activity and outcomes in the early postoperative period. MethodsRetrospective data analysis of patients undergoing orthotopic heart transplantation in our institution from March 2018 to February 2022. The patient population (N = 281) included 223 (79.4%) men and 58 (20.6%) women. The perioperative data of the prepandemic group, March 2018 to February 2020 (N = 130), and the pandemic group, March 2020 to February 2022 (N = 151), were compared. ResultsWe found differences in preoperative inotropic support between the groups (N = 43 (33.1%) vs N = 72 (47.7%), P < .05), respectively). The number of urgent HTs increased during the COVID-19 pandemic (N = 51 (39.2%), vs N = 72 (47.7%), P = .155). Analyzed groups did not differ according to renal, pulmonary, or neurology complications. Intensive care unit (ICU) standing time was longer in the pandemic group (6 days [3-12] vs 11 days [5-12], P < .001). ConclusionWe found that during the COVID-19 pandemic, the number of end-stage heart failure recipients requiring cardiac support increased. Extended time of ICU standing in the pandemic group may be related to the COVID-19 pandemic. Although some efforts have been made to reduce the impact of the pandemic, more research is required.

Evolution of Cardiogenic Shock Management and Development of a Multidisciplinary Team-Based Approach: Ten Years Experience of a Single Center.

Background: The management of cardiogenic shock (CS) after ACS has evolved over time, and the development of a multidisciplinary team-based approach has been shown to improve outcomes, although mortality remains high. Methods: All consecutive patients with ACS-CS admitted at our CICU from March 2012 to July 2021 were included in this single-center retrospective study. In 2019, we established a "shock team" consisting of a cardiac intensivist, an interventional cardiologist, an anesthetist, and a cardiac surgeon. The primary outcome was in-hospital mortality. Results: We included 167 patients [males 67%; age 71 (61-80) years] with ischemic CS. The proportion of SCAI shock stages from A to E were 3.6%, 6.6%, 69.4%, 9.6%, and 10.8%, respectively, with a mean baseline serum lactate of 5.2 (3.1-8.8) mmol/L. Sixty-six percent of patients had severe LV dysfunction, and 76.1% needed ≥ 1 inotropic drug. Mechanical cardiac support (MCS) was pursued in 91.1% [65% IABP, 23% Impella CP, 4% VA-ECMO]. From March 2012 to July 2021, we observed a significative temporal trend in mortality reduction from 57% to 29% (OR = 0.90, p = 0.0015). Over time, CS management has changed, with a significant increase in Impella catheter use (p = 0.0005) and a greater use of dobutamine and levosimendan (p = 0.015 and p = 0.0001) as inotropic support. In-hospital mortality varied across SCAI shock stages, and the SCAI E profile was associated with a poor prognosis regardless of patient age (OR 28.50, p = 0.039). Conclusions: The temporal trend mortality reduction in CS patients is multifactorial, and it could be explained by the multidisciplinary care developed over the years.

Mechanical ventilation during extracorporeal membrane oxygenation support - New trends and continuing challenges.

The impact of mechanical ventilation on the survival of patients supported with veno-venous extracorporeal membrane oxygenation (V-V ECMO) due to severe acute respiratory distress syndrome (ARDS) remains still a focus of research. Recent guidelines, randomized trials, and registry data underscore the importance of lung-protective ventilation during respiratory and cardiac support on ECMO. This approach includes decreasing mechanical power delivery by reducing tidal volume and driving pressure as much as possible, using low or very low respiratory rate, and a personalized approach to positive-end expiratory pressure (PEEP) setting. Notably, the use of ECMO in awake and spontaneously breathing patients is increasing, especially as a bridging strategy to lung transplantation. During respiratory support in V-V ECMO, native lung function is of highest importance and adjustments of blood flow on ECMO, or ventilator settings significantly impact the gas exchange. These interactions are more complex in veno-arterial (V-A) ECMO configuration and cardiac support. The fraction on delivered oxygen in the sweep gas and sweep gas flow rate, blood flow per minute, and oxygenator efficiency have an impact on gas exchange on device side. On the patient side, native cardiac output, native lung function, carbon dioxide production (VCO2), and oxygen consumption (VO2) play a role. Avoiding pulmonary oedema includes left ventricle (LV) distension monitoring and prevention, pulse pressure >10mm Hg and aortic valve opening assessment, higher PEEP adjustment, use of vasodilators, ECMO flow adjustment according to the ejection fraction, moderate use of inotropes, diuretics, or venting strategies as indicated and according to local expertise and resources. Understanding the physiological principles of gas exchange during cardiac support on femoro-femoral V-A ECMO configuration and the interactions with native gas exchange and haemodynamics are essential for the safe applications of these techniques in clinical practice. Proning during ECMO remains to be discussed until further data is available from prospective, randomized trials implementing individualized PEEP titration during proning.

Prevention of Acute Kidney Injury in People with Diabetes in the Intensive Care Unit

Prevention of acute kidney injury (AKI) in the intensive care unit (ICU) is a management strategy with a multidisciplinary approach. Sepsis being the most common cause requires immediate treatment with antimicrobials. Other causes such as cardiogenic shock, postoperative cause, and drug-induced injury are not infrequent in diabetic patients. Control of blood sugar and accompanying electrolyte abnormalities requires expertise. Contrast use is necessary in ICU patients which adds insult to the injury. A point-of-care ultrasound is a mandatory imaging for evaluation of the kidneys and to assess for inferior vena cava collapsibility. Nutrition plays an important component of the therapy, and fluid replacement and the use of vasopressors are necessary. Cardiac support with an intra-aortic balloon pump and extracorporeal membrane oxygenation with the ventricular-assisted device is necessary in maintaining hemodynamic status. Artificial intelligence and a new technological approach with a multidisciplinary team comprising a nephrologist, intensivist, cardiologist, hepatologist, infectious disease specialist, and nutritionist work as a team in preventing AKI in People with diabetes in the ICU.

Extra-Corporeal Membrane Oxygenation in Pregnancy.

Extracorporeal membrane oxygenation (ECMO) is a cardiac or pulmonary function support system that is used in cases of refractory organ failure in addition to conventional treatment. Currently, Level I evidence is not yet available, which reflects improved outcomes with ECMO in pregnant women, the use in pregnancy should be indicated in selected cases and only in specialized centers. We searched articles in the most important scientific databases from 2009 until 31 December 2023 consulting also the site ClinicalTrials.com to find out about studies that have been recently conducted or are currently ongoing. We matched the combination of the following keywords: "ECMO and pregnancy", "H1N1 and pregnancy", "COVID-19 and pregnancy", "ARDS and pregnancy", "ECMO and pregnancy AND (cardiac arrest)". We selected the following number of articles for each keyword combination: "ECMO and pregnancy" (665 articles); "ECMO and influenza H1N1" (384 articles); "pregnancy and influenza H1N1" (1006 articles); "pregnancy and ARDS" (2930 articles); "ECMO and pregnancy and ARDS and influenza H1N1" (24 articles); and "[ECMO and pregnancy AND (cardiac arrest)]" (74 articles). After careful inspection, only 43 papers fitted our scope. There are two types of ECMO: venous-venous (VV-ECMO) and venous-arterial (VA-ECMO). The first-one is necessary to cope with severe hypoxia: oxygen-depleted blood is taken from the venous circulation, oxygenated, and carbon dioxide removed from the extracorporeal circuit and returned to the same venous system. The VA-ECMO is a type of mechanical assistance to the circulatory system that allows to put the failing organ at rest by ensuring adequate oxygenation and systemic de-oxygenation, avoiding multi-organ failure. The main indications for ECMO support in pregnant women are cardiogenic shock, acute respiratory distress syndrome (ARDS), pulmonary embolism, and eclampsia. There are also fetal indications for ECMO, and they are fetal distress, hypoxic-ischemic encephalopathy (HIE), and twin-to-twin transfusion syndrome (TTTS). Until now, based on the outcomes of the numerous clinical studies conducted, ECMO has been shown to be a successful therapeutic strategy in cases where medical treatment has been unsuccessful. In well-selected pregnant patients, it appears to be safe and associated with a low risk of maternal and fetal complications. The aim of this review is to report the main properties of ECMO (VV and VA) and the indications for its use in pregnant women.

Aortic arch blood flow measurements as a predictor of successful ECMO weaning in cardiogenic shock

ObjectiveAcute cardiogenic shock is a life-threatening condition with mortality rates of up to 50%. If conventional therapy fails, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) therapy has emerged to a promising alternative for temporary cardiac and respiratory support in specialized centers. However, it is only a bridge to recovery, final decision, heart transplantation or the permanent implantation of a left ventricular assist device. Therefore, the identification of the optimum weaning time point is challenging, and standardized weaning protocols are rare. MethodsIn this explorative pilot study, we evaluated the potential benefit of blood flow measurements in the aortic arch using an ultrasonic cardiac output monitor (USCOM) for the primary endpoint of successful VA-ECMO weaning. 12 patients under VA-ECMO therapy for acute cardiogenic shock and a hemodynamic condition which qualified for a stepwise weaning process were included in this study. Main exclusion criterion was the presence of additional venting therapy for left ventricular unloading, e.g. Impella. Statistical comparisons were performed using the Mann-Whitney test and corrected for multiple testing by the Holm-Sidak method. ResultsPeak velocity of flow in the aortic arch showed a positive correlation with weaning success independent of ECMO flow (weaning success vs. failure: 0.75 vs. 0.35 m/s (low ECMO support), p = 0.049), whereas we identified only a trend for mean pressure gradient, minute distance and stroke volume index. ConclusionWe hypothesize, that USCOM might provide an additive benefit to conventional strategies in its ability to predict successful VA-ECMO weaning and prevent pulmonary congestion. Larger upcoming trials are required to address this relevant topic and provide standardized treatment protocols for optimized weaning in the future.

Mechanical Circulatory Support Systems in Fulminant Myocarditis: Recent Advances and Outlook.

Background: Fulminant myocarditis (FM) constitutes a severe and life-threatening form of acute cardiac injury associated with cardiogenic shock. The condition is characterised by rapidly progressing myocardial inflammation, leading to significant impairment of cardiac function. Due to the acute and severe nature of the disease, affected patients require urgent medical attention to mitigate adverse outcomes. Besides symptom-oriented treatment in specialised intensive care units (ICUs), the necessity for temporary mechanical cardiac support (MCS) may arise. Numerous patients depend on these treatment methods as a bridge to recovery or heart transplantation, while, in certain situations, permanent MCS systems can also be utilised as a long-term treatment option. Methods: This review consolidates the existing evidence concerning the currently available MCS options. Notably, data on venoarterial extracorporeal membrane oxygenation (VA-ECMO), microaxial flow pump, and ventricular assist device (VAD) implantation are highlighted within the landscape of FM. Results: Indications for the use of MCS, strategies for ventricular unloading, and suggested weaning approaches are assessed and systematically reviewed. Conclusions: Besides general recommendations, emphasis is put on the differences in underlying pathomechanisms in FM. Focusing on specific aetiologies, such as lymphocytic-, giant cell-, eosinophilic-, and COVID-19-associated myocarditis, this review delineates the indications and efficacy of MCS strategies in this context.

Veno-arterial extracorporeal membrane oxygenation for respiratory and cardiac support in neonates: a single center experience.

Extracorporeal membrane oxygenation (ECMO) is an advanced life support that has been utilized in the neonate for refractory respiratory and circulatory failure. Striving for the best outcomes and understanding optimal surgical techniques continue to be at the forefront of discussion and research. This study presents a single-center experience of cervically cannulated neonatal patients on V-A ECMO, a description of our cannulation/decannulation techniques and our patient outcomes. Single center retrospective review of neonates who received neck V-A ECMO support from January 2012 to December 2022. The data and outcomes of the patients were retrospectively analyzed. A total of 78 neonates received V-A ECMO support. There were 66 patients that received ECMO for respiratory support, the other 12 patients that received ECMO for cardiac support. The median duration of ECMO support was 109 (32-293) hours for all patients. During ECMO support, 20 patients died and 5 patients discontinued treatment due to poor outcome or the cost. A total of 53 (68%) patients were successfully weaned from ECMO, but 3 of them died in the subsequent treatment. Overall 50 (64%) patients survived to hospital discharge. In this study, 48 patients were cannulated using the vessel sparing technique, the other 30 patients were cannulated using the ligation technique. We found no significant difference in the rates of normal cranial MRI at discharge between survivors with and without common carotid artery ligation. We achieved satisfactory outcomes of neonatal ECMO in 11-year experience. This study found no significant difference in early neuroimaging between survivors with and without common carotid artery ligation. The long-term neurological function of ECMO survivors warranted further follow-up and study.

Recipient Pericardial Apolipoprotein Levels Might Be an Indicator of Worse Outcomes after Orthotopic Heart Transplantation.

End-stage heart failure (ESHF) leads to hypoperfusion and edema formation throughout the body and is accompanied by neurohormonal and immunological alterations. Orthotopic heart transplantation (HTX) has been used as a beneficial option for ESHF. Due to the shortage of donor hearts, the ideal matching and timing of donors and recipients has become more important. In this study, our aim was to explore the relationship between the clinical outcomes of HTX and the cytokine and apolipoprotein profiles of the recipient pericardial fluid obtained at heart transplantation after opening the pericardial sac. The clinical data and the interleukin, adipokine, and lipoprotein levels in the pericardial fluid of twenty HTX recipients were investigated. Outcome variables included primer graft dysfunction (PGD), the need for post-transplantation mechanical cardiac support (MCS), International Society for Heart and Lung Transplantation grade ≥2R rejection, and mortality. Recipient risk scores were also investigated. Leptin levels were significantly lower in patients with PGD than in those without PGD (median: 6.36 (IQR: 5.55-6.62) versus 7.54 (IQR = 6.71-10.44); p = 0.029). Higher ApoCII levels (median: 14.91 (IQR: 11.55-21.30) versus 10.31 (IQR = 10.02-13.07); p = 0.042) and ApoCIII levels (median: 60.32 (IQR: 43.00-81.66) versus 22.84 (IQR = 15.84-33.39); p = 0.005) were found in patients (n = 5) who died in the first 5 years after HTX. In patients who exhibited rejection (n = 4) in the first month after transplantation, the levels of adiponectin (median: 74.48 (IQR: 35.51-131.70) versus 29.96 (IQR: 19.86-42.28); p = 0.039), ApoCII (median: 20.11 (IQR: 13.06-23.54) versus 10.32 (IQR: 10.02-12.84); p = 0.007), and ApoCIII (median: 70.97 (IQR: 34.72-82.22) versus 26.33 (IQR: 17.18-40.17); p = 0.029) were higher than in the nonrejection group. Moreover, the pericardial thyroxine (T4) levels (median: 3.96 (IQR: 3.49-4.46) versus 4.69 (IQR: 4.23-5.77); p = 0.022) were lower in patients with rejection than in patients who did not develop rejection. Our results indicate that apolipoproteins can facilitate the monitoring of rejection and could be a useful tool in the forecasting of early and late complications.

High Rate of Kidney Graft Failure after Simultaneous Heart-Kidney Transplantation.

The indications and outcomes of Simultaneous heart-kidney transplantation (SHKT) remain sub-optimally defined. Risk factors for renal graft failure after SHKT also remain poorly defined. We analyzed the renal graft outcomes among SHKT recipients using United Network for Organ Sharing database from 2015-2020. To evaluate for factors associated with poor renal outcomes, we compared SHKT and kidney transplantation alone (KTA) recipients using propensity score matching. Among SHKT recipients, rate of primary non-function (PNF) of kidney graft was 3%, 30-day kidney graft failure rate was 7.0%, and the 30-day post-transplant mortality rate was 4.1%. The incidence of delayed kidney graft function (KDGF) was 27.5%. Kidney graft failure was seen early post-SHKT with most common causes of patient death (43.9%) and PNF of kidney graft (41.5%). One-year and two-year patient survival was 89.2% and 86.5%, and one-year and two-year freedom from kidney graft failure was 85.4% and 82.7%, respectively. In subgroup analysis of SHKT recipients, use of pre-transplant mechanical cardiac support (adjusted Odds Ratio (aOR) 2.57, P=0.017), higher cPRA (aOR 1.76, P=0.016), and older donor age per 10 years (aOR 1.94, P=0.001) were associated with PNF. Pre-transplant extracorporeal membrane oxygenation support was associated with the increased risk of 30-day recipient mortality (aOR 5.55, P=0.002). Increased 30-day graft failure was seen in SHKT recipients with pre-transplant mechanical cardiac support (aOR 1.77, P=0.038) and dialysis at time of transplant (aOR 1.72, P=0.044). Multivariable Cox-Hazard analysis demonstrated that SHKT, when compared to KTA, is associated with increased kidney graft failure (Hazard Ratio, 2.56, P<0.001) and recipient mortality (Hazard Ratio: 2.65, P<0.001). SHKT is associated with high rates of kidney graft failure. Identification of risk factors for renal graft failure can help optimize recipient selection for SHKT vs Kidney after HT, especially after introduction of the new safety-net policy.

Cardiac Treatment and Monitoring Devices Encountered on Chest Radiography: From Radiologic Appearances to Potential Complications

Cardiac monitoring, support, and treatment devices are frequently seen on chest radiographs. As cardiac therapeutic interventions evolve, these devices grow in prevalence and diversity. New devices are introduced on a regular basis, and although knowing their specific names is not critical, it is imperative to recognize their radiologic appearances, understand their purpose, and be aware of potential complications associated with their use

State of the Art Review of Surgical Techniques for Microaxial Flow Pump Implantation.

Recently, temporary mechanical circulatory support (tMCS) has been increasingly used for cardiogenic shock therapy. Originally designed as a bail-out option for patients who could not be weaned from cardiopulmonary bypass, the indications for tMCS have been expended and now enable us to support a wide range of patients with various cardiac pathologies. Modern tMCS devices include microaxial flow pumps (mAFP) which are small, versatile systems that can provide both acute cardiac support and cardiac protection for high-risk interventions. In this paper, we review different surgical implantation techniques with modern mAFP as well as specific aspects of preoperative indications and patient evaluation.

Direct and continuous dosing of propofol can saturate Ex vivo ECMO circuit to improve propofol recovery

Background: Extracorporeal membrane oxygenation (ECMO) is a cardiopulmonary bypass device that provides life-saving complete respiratory and cardiac support in patients with cardiorespiratory failure. The majority of drugs prescribed to patients on ECMO lack a dosing strategy optimized for ECMO patients. Several studies demonstrated that dosing is different in this population because the ECMO circuit components can adsorb drugs and affect drug exposure substantially. Saturation of ECMO circuit components by drug disposition has been posited but has not been proven. In this study, we have attempted to determine if propofol adsorption is saturable in ex vivo ECMO circuits. Methods: We injected ex vivo ECMO circuits with propofol, a drug that is highly adsorbed to the ECMO circuit components. Propofol was injected as a bolus dose (50 μg/mL) and a continuous infusion dose (6 mg/h) to investigate the saturation of the ECMO circuit. Results: After the bolus dose, only 27% of propofol was recovered after 30 minutes which is as expected. However, &gt;80% propofol was recovered after the infusion dose which persisted even when the infusion dose was discontinued. Conclusion: Our results suggest that if ECMO circuits are dosed directly with propofol, drug adsorption can be eliminated as a cause for altered drug exposure. Field of Research: Artificial Lung/ECMO

Extracorporeal membrane oxygenation in South Africa: Experience from a single centre in the private sector.

Extracorporeal membrane oxygenation (ECMO) is an advanced, resource-intensive technology used in a limited capacity in South Africa (SA). Minimal data on the use of ECMO in SA are available. To describe the indications, early outcome and comorbidities of patients placed on ECMO in the highest-volume ECMO centre in SA. We performed a single-centre retrospective review of all adult patients supported with any form of ECMO from August 2016 to December 2018. Operative and clinical records were reviewed. The primary objective of this study was to review the outcome of patients placed on ECMO in the form of survival to hospital discharge. The secondary objectives were to identify population-specific comorbidities and indications for ECMO that could be associated with non-survival and to compare outcome with known risk scores in the form of the Respiratory ECMO Survival Prediction (RESP) and Survival After Venoarterial ECMO (SAVE) scores. One hundred and seven patients were identified. The primary indication for ECMO was respiratory support in 78 patients and cardiac support in 29 patients. Forty-seven patients were discharged from hospital, with a 44.0% overall survival rate. Gender (p=0.039), age (p=0.019) and hypertension (p=0.022) were associated with death in univariate logistic regression analysis. However, after adjusting for potential confounding in multivariate logistic regression analysis, the association was no longer significant. In the all respiratory support group, patients in risk class IV had better than predicted survival according to the RESP score, while risk classes I, II and III had worse than predicted survival. In the circulatory support group, all risk classes had worse than predicted survival according to the SAVE score. We report ECMO outcomes in SA for the first time. We identified very high mortality rates for patients transferred on ECMO from other facilities and for patients converted from venovenous ECMO to venoarterial ECMO. Although our outcomes were comparable in some of the risk classes, further external validation of the SAVE and RESP scores will be needed to compare our outcomes with these scores. What the study adds. We report on extracorporeal membrane oxygenation (ECMO) outcomes in South Africa for the first time. We identified a high mortality rate in patients transferred on ECMO from other facilities, and in patients converted from venovenous ECMO to venoarterial ECMO.Implications of the findings. Transferred patients had a high mortality rate. The reason for this should be further investigated and may highlight the need for possible protocols to assist with appropriate timing of patient transfers and possible earlier intervention or transfer.

Addition by Subtraction in Mechanical Cardiac Support

Addition by Subtraction in Mechanical Cardiac Support

Abstract 18575: Impact of Mechanical Circulatory Support on In-Hospital Mortality in Ventricular Tachycardia Ablation: A United States Nationwide Analysis

Background: Mechanical circulatory support (MCS) devices have emerged as a valuable tool in ventricular tachycardia (VT) ablation procedures, offering potential benefits such as improved hemodynamic stability, preserved organ perfusion, and optimized coronary perfusion during prolonged VT induction and mapping. However, the impact of different MCS modalities on in-hospital mortality following VT ablation remains unclear. Objective: This study aimed to investigate the impact of various MCS modalities on in-hospital mortality in those undergoing VT ablation during hospitalization. Method: We analyzed data from the National Inpatient Sample to identify patients who underwent VT ablation and received transient mechanical cardiac support between 2019 and 2020. The primary endpoint was in-hospital mortality, stratified by different MCS modalities. Additionally, we explored independent predictors of in-hospital mortality. Result: A total of 850 patients underwent VT ablation and required MCS from January 2019 to December 2020. Among these patients, extracorporeal membrane oxygenation (ECMO), percutaneous left ventricular assist device (PLVAD), intra-aortic balloon pump (IABP), and a combination of more than one MCS modality were utilized in 5.8%, 64.7%, 18.8%, and 10.5% of cases, respectively. The in-hospital mortality rates for these groups were 40%, 16%, 22%, and 61%, respectively (p&lt;0.01). Notably, the use of multiple MCS modalities, female sex, other races, and self-payment were independent predictors of mortality, with adjusted odds ratios (aOR) of 21.9 (p=0.008; 95% confidence interval [CI]: 2.2-217.1), 9.27 (p=0.045; 95% CI: 1.1-82.1), 27 (p=0.038; 95% CI: 1.1-29.4), and 27.6 (p=0.041; 95% CI: 1.2-660.8), respectively. Conclusion: Our study highlights that the use of multiple MCS modalities, female sex, other races, and self-payment are independent predictors of in-hospital mortality, highlighting the need for careful consideration and selection of MCS for VT ablation patients.

Abstract 18864: A Novel Technique to Improve Vector Uptake for Cardiac Gene Therapy

Introduction: Cardiac gene therapy with adeno-associated virus (AAV) has promise. However, clinical trials with intracoronary (IC) delivery have been challenged by low efficacy. Hypothesis: We predicted that AAV uptake could be enhanced using a catheter-based mechanical cardiac support device (MCS) to facilitate IC delivery with brief coronary balloon occlusions in a pig model of myocardial infarction (MI). Aims: We aimed to: 1) confirm that MCS could support hemodynamics during coronary balloon occlusions, and 2) determine whether this technique could improve vector uptake and cardiac gene expression after HF onset. Methods: A week after MI, 12 Yorkshire pigs (36.6±1.45 kg, male n=6) received AAV6 encoding for luciferase by one of four delivery methods (n=3/group) (Figure 1). Tissues were harvested 1 mo later for analysis. A similar experiment was conducted with gold nanoparticles (GNPs) in place of AAV by either continuous or CAO+CSO delivery (n=4) with same-day cardiac harvest. GNP presence was seen by electron microscopy. Results: MCS maintained blood pressure and prevented arrhythmias during coronary balloon occlusions. Application of MCS during continuous infusion did not significantly alter AAV genome uptake (vg) or luciferase expression (luc). CAO+CSO delivery increased both vg and luc across heart regions, with notable significance at the infarct-border region vs continuous delivery (vg: p=0.027; luc: p=0.032). Vg was also positively associated with luc (Figure 2). Improved uptake was further supported by greater GNP presence with CAO+CSO delivery. Conclusion: MCS can be utilized to optimize IC gene delivery in a safe and clinically-applicable way.

Effects of genetic selection for fast growth on the development of wooden breast myopathy in broilers

ABSTRACT 1. This study investigated the physiological and molecular mechanisms leading to wooden breast (WB) by comparing growth parameters, oxygen consumption rate, thyroid hormone and gene expression patterns in fast- versus slow-growing broiler lines (Cobb500 and L1986, respectively). 2. WB was observed in Cobb500 broilers only and was first diagnosed on d 21 post-hatch. Compared to the slow-growing L1986, Cobb500 showed a significantly higher growth rate, relative breast weight, breast thickness, meat pH and water-retention capacity (drip loss). Correspondingly, there was significantly lower relative heart weight, relative right ventricular weight, triiodothyronine and thyroxine concentrations and oxygen consumption rate. 3. Compared to No-WB Cobb500, the WB-affected samples exhibited higher relative breast weight, breast thickness and drip loss and lower plasma total thyroxine (T4) concentrations. 4. Selection for fast growth was associated with differential expression of genes involved in hypoxia (PLOD2), energy metabolism (FABP3, FABP4, CD36, and LPL), endoplasmic reticulum stress, muscle regeneration (CSRP3) and fibre-type switching (ANKRD1). WB-affected samples exhibited an upregulation of CSRP3, PLOD2 and ANKRD1, while CD36 was downregulated. Taken together, selection for fast growth and muscle gain is not matched by adequate cardiac and metabolic support systems.