The History of Extracorporeal Membrane Oxygenation and the Development of Extracorporeal Membrane Oxygenation Anticoagulation.

Extracorporeal membrane oxygenation (ECMO) was first started for humans in early 1970s by Robert Bartlett. Since its inception, there have been numerous challenges with extracorporeal circulation, such as coagulation and platelet activation, followed by consumption of coagulation factors and platelets, and biocompatibility of tubing, pump, and oxygenator. Unfractionated heparin (heparin hereafter) has historically been the defacto anticoagulant until recently. Also, coagulation monitoring was mainly based on bedside activated clotting time and activated partial thromboplastin time. In the past 50 years, the technology of ECMO has advanced tremendously, and thus, the survival rate has improved significantly. The indication for ECMO has also expanded. Among these are clinical conditions such as postcardiopulmonary bypass, sepsis, ECMO cardiopulmonary resuscitation, and even severe coronavirus disease 2019 (COVID-19). Not surprisingly, the number of ECMO cases has increased according to the Extracorporeal Life Support Organization Registry and prolonged ECMO support has become more prevalent. It is not uncommon for patients with COVID-19 to be on ECMO support for more than 1 year until recovery or lung transplant. With that being said, complications of bleeding, thrombosis, clot formation in the circuit, and intravascular hemolysis still remain and continue to be major challenges. Here, several clinical ECMO experts, including the "Father of ECMO"-Dr. Robert Bartlett, describe the history and advances of ECMO.

Cardiogenic shock trajectories: is the Society for Cardiovascular Angiography and Interventions definition the right one?

PURPOSE OF REVIEW: We review the current Society for Cardiovascular Angiography and Interventions (SCAI) cardiogenic shock classification system and consider alternatives or iterations that may enhance our current descriptions of cardiogenic shock trajectory. RECENT FINDINGS: Several studies have identified the potential prognostic value of serial SCAI stage re-assessment, usually within the first 24 h of shock onset, to predict deterioration and clinical outcomes across shock causes. In parallel, numerous registry-based analyses support the utility of a more precise assessment of the macrocirculation and microcirculation, leveraging invasive haemodynamics, imaging and additional laboratory and clinical markers. The emergence of machine learning and artificial intelligence capabilities offers the opportunity to integrate multimodal data into high fidelity, real-time metrics to more precisely define trajectory and inform our therapeutic decision making. SUMMARY: Whilst the SCAI staging system remains a pivotal tool in cardiogenic shock assessment, communication and reassessment, it is vital that the sophistication with which we measure and assess shock trajectory evolves in parallel our understanding of the complexity and variability of clinical course and clinical outcomes.

The management of heart failure cardiogenic shock: an international RAND appropriateness panel.

BACKGROUND: Observational data suggest that the subset of patients with heart failure related CS (HF-CS) now predominate critical care admissions for CS. There are no dedicated HF-CS randomised control trials completed to date which reliably inform clinical practice or clinical guidelines. We sought to identify aspects of HF-CS care where both consensus and uncertainty may exist to guide clinical practice and future clinical trial design, with a specific focus on HF-CS due to acute decompensated chronic HF. METHODS: A 16-person multi-disciplinary panel comprising of international experts was assembled. A modified RAND/University of California, Los Angeles, appropriateness methodology was used. A survey comprising of 34 statements was completed. Participants anonymously rated the appropriateness of each statement on a scale of 1 to 9 (1-3 as inappropriate, 4-6 as uncertain and as 7-9 appropriate). RESULTS: Of the 34 statements, 20 were rated as appropriate and 14 were rated as inappropriate. Uncertainty existed across all three domains: the initial assessment and management of HF-CS; escalation to temporary Mechanical Circulatory Support (tMCS); and weaning from tMCS in HF-CS. Significant disagreement between experts (deemed present when the disagreement index exceeded 1) was only identified when deliberating the utility of thoracic ultrasound in the immediate management of HF-CS. CONCLUSION: This study has highlighted several areas of practice where large-scale prospective registries and clinical trials in the HF-CS population are urgently needed to reliably inform clinical practice and the synthesis of future societal HF-CS guidelines.

Proportional pulmonary pulse pressure: A new index to assess response to veno-arterial extracorporeal membrane oxygenation.

BACKGROUND: Based on theoretical physiology, the ratio of pulmonary artery pulse pressure to mean pulmonary pressure (PP-MPAP), termed proportional pulmonary pulse pressure, provides a measure of coupling between the right ventricle and the pulmonary circulation. This study tested the hypothesis that lower PP-MPAP ratio was associated with left ventricular (LV) distension in patients with cardiogenic shock who underwent extracorporeal life support (ECLS). METHODS: This is a retrospective observational single-centre study of 22 patients with cardiogenic shock who underwent ECLS as the primary support modality without and with LV distension and Impella unloading. The relationship between post-support PP-MPAP and 12-hour lactate clearance was also assessed. RESULTS: Of the 22 patients: 10 patients underwent additional Impella unloading due to LV distension (Group 1) and 12 patients on ECLS only without LV distension (Group 2). As predicted by the theoretical model, PP-MPAP on ECLS dropped in Group 1 (pre-Impella) from 0.473 ± 0.067 to 0.372 ± 0.087, p < 0.001; but increased in Group 2 patients without LV distension (0.518 ± 0.070 to 0.549 ± 0.072, p = 0.002). Impella support in Group 1 increased PP-MPAP (0.372 ± 0.087 to 0.615 ± 0.094, p < 0.001). On multiple regression analysis, post-support PP-MPAP was significantly associated with 12-hour lactate clearance. CONCLUSION: Changes in PP-MPAP is associated hemodynamic response to ECLS and 12-hour lactate clearance. This simple parameter may guide therapeutic optimization in cardiogenic shock and ECLS.

Pathophysiology of severe primary graft dysfunction in orthotopic heart transplantation.

BACKGROUND: A series of insults on the donor heart result in pathophysiological changes that manifest as primary graft dysfunction (PGD) post-orthotopic heart transplantation. The objectives of this study were: (i) describe the pathophysiology of severe PGD using an established cardiovascular model; and (ii) the evolution of the pathophysiology during recovery from severe PGD. METHODS: Hemodynamic data from 20 consecutive patients with severe PGD (need for mechanical circulatory support, MCS) at baseline (T0), 6 h (T6) and "recovery" (explant of support), and 20 consecutive patients without severe PGD were used to model the pathophysiology using the cardiovascular model described by Burkhoff and Dickstein. RESULTS: There was a progressive (from T0 to T6) up- and leftward shift in the diastolic pressure-volume relationship, especially of the right ventricle (RV), resulting in reduced capacitance. RV end-systolic elastance (Ees) was significantly elevated in severe PGD but preload-recruitable stroke work (PRSW) was significantly lower compared to patients without severe PGD. "Recovery" (after liberation from MCS) was associated with improvement in RV Ees, chamber capacitance and PRSW, although they remained significantly lower than patients without severe PGD. CONCLUSION: Severe PGD of the dominant right heart failure phenotype is characterized by reduced chamber capacitance, increased "stiffness" and impaired contractility. Complete normalization was not required for successful weaning of MCS.

Cardiac Power Output Index and Severe Primary Graft Dysfunction After Heart Transplantation.

OBJECTIVES: To evaluate the value of cardiac power output index (CPOi) in predicting severe primary graft dysfunction (PGD) after heart transplantation (defined as mechanical circulatory support [MCS] and/or mortality <30 days after transplant). DESIGN: Observational cohort study. SETTING: A heart transplant center in the United Kingdom. PARTICIPANTS: Consecutive patients who underwent heart transplantation from January 2014 to December 2019 (n = 160). Twenty patients were excluded, as MCS was instituted immediately after transplant. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Hemodynamic data on return to the intensive care unit (time 0, T0) and at 6 hours (T6) were collected to calculate CPOi at both points in 140 consecutive patients-22 patients developed severe PGD. The CPOi at T0 correlated with donor-recipient predicted heart mass and inversely with inotrope score. Patients who developed severe PGD had significantly lower CPOi at T0 and T6. The areas under the receiver operating characteristic curve for CPOi at T0 and T6 for the development of severe PGD were 0.90 and 0.92, respectively. Adjusting for vasoactive-inotrope score did not improve discrimination. The probability of severe PGD if CPOi at T0 <0.34 W/m2 and T6 <0.33 W/m2 was 79%, but was only 2% if both CPOi at T0 and T6 were >0.34 W/m2 and >0.33 W/m2, respectively. After adjusting for baseline differences, CPOi at T6 (odds ratio 0.78; 95% CI 0.67-0.91, p = .001) was significantly associated with severe PGD. CONCLUSION: Low CPOi at T0 is associated with severe PGD. Serial assessment of CPOi increases the diagnostic probability of severe PGD.

The Physiology of Continuous-Flow Left Ventricular Assist Devices.

The use of left ventricular assist devices (LVADs) has increased significantly over the past few years, in part because heart transplant activity has plateaued, but also because of the improving clinical outcomes with contemporary continuous-flow LVAD. As such, there is now a growing population of patients with continuous-flow LVADs. Management of these patients is complicated by the altered circulatory physiology, because continuous-flow LVADs provide a parallel circulation from the heart to the aorta, which interacts with the native left heart (systemic) circulation with consequent effects on the right heart circulation. In addition, the displayed pump parameters can mislead the unwary clinician. An understanding of LVAD physiology can guide clinicians in the management of patients with LVADs. This review describes the basic design of axial and centrifugal continuous-flow LVADs, the functional anatomy and physiology of continuous-flow LVADs, and the interaction between the heart and the LVAD. leading to a discussion about the interpretation of the pump parameters in clinical practice.

Extracorporeal Life Support: Physiological Concepts and Clinical Outcomes.

Extracorporeal life support (ECLS) describes a system that involves drainage from the venous circulation and return via an oxygenator into the arterial circulation (veno-arterial extracorporeal membrane oxygenation). ECLS provides effective cardiopulmonary support, but the parallel circulation has complex effects on the systemic and pulmonary circulatory physiology. An understanding of the physiological changes is fundamental to the management of ECLS. In this review, the key physiological concepts and the implications on the clinical management of ECLS are discussed. In addition, the clinical outcomes associated with ECLS in cardiogenic shock are systematically reviewed. The paucity of clinical trials on ECLS highlights the need for randomized trials to guide the selection of patients.

The Effect of Impella CP on Cardiopulmonary Physiology During Venoarterial Extracorporeal Membrane Oxygenation Support.

Left ventricle (LV) distension is a complication of venoarterial extracorporeal membrane oxygenation (VA-ECMO) support. The effects of Impella on the pulmonary circulatory physiology were studied in a single-center study of six consecutive patients on VA-ECMO support who had LV unloading with Impella. Right ventricular stroke volume, pulmonary hemodynamics, and partial pressure of end-tidal CO2 (PETCO2 ) were measured on echocardiogram, pulmonary artery catheter, and capnography, respectively. The addition of Impella CP increased total blood flow and reduced pulmonary artery wedge pressure. There was a small reduction in arterial oxygen saturation as Impella increased LV output. The increase in pulmonary artery capacitance (PCap) exceeded the reduction in pulmonary vascular resistance (PVR), thereby increasing the pulmonary artery time constant (product of PCap and PVR). The right ventricular stroke volume increased and the improvement in pulmonary hemodynamics and blood flow were associated with reduced arterial-PETCO2 gradient. The Impella CP unloads the LV during VA-ECMO support, increasing total flow, reducing RV afterload, and facilitating RV output and pulmonary blood flow with improvement in gas exchange.

Mechanical Circulatory Support for Decompensated Heart Failure.

PURPOSE OF REVIEW: Cardiogenic shock from decompensated heart failure is associated with significant morbidity and mortality. Mechanical circulatory support (MCS) improves haemodynamics and reverses organ dysfunction in critically ill patients with cardiogenic shock. This paper summarises the main modalities of mechanical support and their physiological impact, practical considerations, advantages and disadvantages to facilitate a holistic approach in managing a potentially lethal pathology. RECENT FINDINGS: To date, there remains a lack of large randomised controlled trials to support the use of any mechanical support strategy. Consequently, meta-analyses, registry data and expert consensus in the form of society guidelines are relied upon. Currently, randomised trials are in progress to assess the efficacy of a percutaneous assist device (Impella) and extracorporeal membrane oxygenation. Mechanical support options are centred around the use of counter pulsation and percutaneous assist devices and the use of an extracorporeal pump and are hence varied in means of application, degree of haemodynamic benefit and potential complications. Regardless of future innovations, a timely multidisciplinary approach that incorporates both patient and institutional considerations will always be crucial to a successful outcome.

Sodium Nitroprusside in Patients With Mixed Pulmonary Hypertension and Left Heart Disease: Hemodynamic Predictors of Response and Prognostic Implications.

BACKGROUND: Mixed pulmonary hypertension (PH) in heart failure (HF) is defined by transpulmonary gradient ≥ 12 and/or pulmonary vascular resistance (PVR) ≥ 240 dyne/s/cm(-5), but diastolic pressure gradient (DPG) ≥ 7 mmHg has been proposed more recently. We evaluated the acute hemodynamic response to sodium nitroprusside (SNP) specifically in relation to the proposed DPG criterion ≥7 mmHg and the prognostic significance of response to SNP in patients with mixed PH and advanced HF. METHODS: Ninety-eight consecutive patients with advanced HF and mixed PH underwent cardiac catheterization and acute SNP infusion. Baseline hemodynamic parameters included transpulmonary gradient, PVR, DPG, and pulmonary capacitance (PCap). Hemodynamic response to SNP was defined as a reduction in PVR of at least 20%. The composite endpoint was death/heart transplantation/mechanical circulatory support. RESULTS: Sixty of the 98 patients were SNP responders. SNP resulted in significant reductions in filling pressures and PVR and increase in stroke volume and PCap. DPG (not baseline PVR) was significantly associated with hemodynamic response to SNP on logistic regression analysis. The sensitivity and specificity of a DPG ≥7 mmHg to identify nonresponders to SNP were 74% and 97%, respectively. At median follow-up of 218 (148-324) days, 13 and 19 patients of the SNP responders and nonresponders, respectively, met the composite endpoint (P = .021 by log-rank test). Hemodynamic response to SNP and PCap were independently associated with the composite outcome of survival free from transplantation/mechanical circulatory support. CONCLUSION: Baseline DPG ≥ 7 mmHg is associated with poor PVR response to SNP. PVR response to SNP and PCap are associated with a more favorable prognosis in patients with advanced HF and mixed PH.

Exercise ventilatory parameters for the diagnosis of reactive pulmonary hypertension in patients with heart failure.

BACKGROUND: Reactive pulmonary hypertension (PH) in left heart disease is associated with poor prognosis. This study aimed to evaluate the diagnostic utility of exercise ventilatory parameters on cardiopulmonary exercise testing for the diagnosis of reactive PH in patients with heart failure (HF) and reduced ejection fraction. METHODS: This was a single-center, retrospective analysis of a prospectively collected database of 131 patients with HF who underwent in-hospital assessment for heart transplantation. Pulmonary hemodynamics was assessed by direct cardiac catheterization. Minute ventilation/carbon dioxide production (VE/VCO2) slope, partial pressure of end-tidal carbon dioxide (ETCO2) changes on exercise, oxygen pulse, and exercise oscillatory ventilation were determined from cardiopulmonary exercise testing. RESULTS: Sixty-one of 131 consecutive patients had reactive PH. VE/VCO2 slope (>41), change in ETCO2 on exercise (<1.2 mm Hg) and exercise oscillatory ventilation were independently associated with reactive PH. These 3 parameters in combination produced 3 possible diagnostic scenarios: (1) if all 3 criteria ("if all") were present, (2) if any 2 of the 3 criteria ("2 of 3") were present, and (3) if any of the criteria ("if any") were present. The corresponding positive/negative likelihood ratios for reactive PH if all 3 criteria were present were 3.73/0.83, if 2 of the 3 criteria were present were 2.19/0.45, and if any of the 3 criteria were present were 1.75/0.11. The posttest probability increased from 46% to 76% ("if all" present) and reduced to 9% (if none of the criteria was present). CONCLUSION: Ventilatory parameters on cardiopulmonary exercise test are associated with reactive PH in patients with HF. The absence of abnormalities in these 3 ventilatory parameters can effectively exclude reactive PH in patients with HF and poor ejection fraction.

A novel 'shunt fraction' method to derive native cardiac output during liberation from central VA ECMO.

The Fick principle is an established method to quantify intracardiac shunts. The Fick principle has also found utility in the practice of extracorporeal membrane oxygenation (ECMO). This report describes a novel 'shunt fraction' method to calculate intrinsic cardiac output in central (right atrial-to-aorta) ECMO. The physiological basis of this 'shunt fraction' method is described, followed by the case presentation that details the clinical application of this method of quantifying intrinsic cardiac output to guide weaning and liberation from central VA ECMO.

Antifungal prophylaxis against invasive Candida and Aspergillus infection in adult heart transplant recipients: protocol for a systematic review and meta-analysis.

INTRODUCTION: Invasive fungal infections (IFI) can contribute to increased mortality and morbidity rates after heart transplant in adults. The most common causes are Aspergillus and Candida species. There is uncertainty on how effective antifungal prophylaxis is against Candida spp infections and limited guidance on the prevention of Aspergillus spp infections. This systematic review and meta-analysis will assess the literature to see if antifungal prophylaxis reduces the incidence of IFI after heart transplant in adults. METHODS AND ANALYSIS: This systematic review protocol follows the Preferred Reporting Items for Systematic reviews and Meta Analysis guidelines. A systematic search of the Cochrane Library, Web of Science, Scopus, Embase, MEDLINE, and Proquest databases will be undertaken. Reference lists of retrieved publications and conference abstracts will also be searched. Title, abstract and full-text screening will be undertaken by two reviewers. Discrepancies will be resolved by a third reviewer. Studies with paediatric patients, multi-organ transplants, or patients with a second heart transplant will be excluded, along with those who do not have clear definitions and diagnostic criteria for IFI. Risk of bias will be assessed using the Cochrane Risk of Bias 2 tool and the Risk of Bias in Non-randomised Studies of Interventions tool. A meta-analysis will be carried out, but if studies are not deemed to be sufficiently similar, only a narrative synthesis will be undertaken. ETHICS AND DISSEMINATION: Ethical approval is not required for this systematic review as primary data will not be collected. The results of the review will be disseminated through publication in an academic journal and scientific conferences. PROSPERO REGISTRATION NUMBER: CRD42024516588.

Derivation of Stroke Volume from Pulmonary Artery Pressures.

INTRODUCTION: Intermittent cardiac output (CO) studies using thermodilution are considered the gold standard. We have developed a stroke volume (SV) calculator from pulmonary pulse pressure (PP) to allow continuous monitoring of SV and CO from PP. METHODS: Hemodynamic data on 169 patients following orthotopic heart transplantation were used to compare our calculator-derived SV (and SV index, or SVi) against thermodilution-derived SV on admission into intensive care unit immediately following heart transplantation (T0) and 6 h after admission (T6). RESULTS: The calculated SV correlated with thermodilution-derived SV T0 (r = 0.920, p < 0.001, coefficient of 0.539 and the constant of 2.06). The median calculator SV, adjusted for coefficient and constant, was 48.4 ml (37.7, 60.7), comparable to the median thermodilution-derived SV 47.9 ml (37.5, 61.0), p = 0.737 with acceptable agreement on Bland-Altman plots. The thermodilution-derived SVi was 28.1 ml (19.7, 38.7) and adjusted calculator-derived SVi 28.9 ml (19.7, 39.9), p = 0.781. At T6, median thermodilution-derived SVi was 27.7 ml (19.5, 35.9) compared to the calculator-derived SVi median of 26.1 ml (17.7, 37.7), p = 0.203. CONCLUSIONS: Changes in PP can be used to track changes in SV using this calculator. Changes in PP may be used to assess response to treatment in the early post-operative period.

Hemodynamic management of cardiogenic shock in the intensive care unit.

Hemodynamic derangements are defining features of cardiogenic shock. Randomized clinical trials have examined the efficacy of various therapeutic interventions, from percutaneous coronary intervention to inotropes and mechanical circulatory support (MCS). However, hemodynamic management in cardiogenic shock has not been well-studied. This State-of-the-Art review will provide a framework for hemodynamic management in cardiogenic shock, including a description of the 4 therapeutic phases from initial 'Rescue' to 'Optimization', 'Stabilization' and 'de-Escalation or Exit therapy' (R-O-S-E), phenotyping and phenotype-guided tailoring of pharmacological and MCS support, to achieve hemodynamic and therapeutic goals. Finally, the premises that form the basis for clinical management and the hypotheses for randomized controlled trials will be discussed, with a view to the future direction of cardiogenic shock.

Pulmonary artery wave intensity analysis in pulmonary hypertension associated with heart failure and reduced left ventricular ejection fraction.

Wave intensity analysis (WIA) uses simultaneous changes in pressure and flow velocity to determine wave energy, type, and timing of traveling waves in the circulation. In this study, we characterized wave propagation in the pulmonary artery in patients with pulmonary hypertension associated with left-sided heart disease (PHLHD) and the effects of dobutamine. During right heart catheterization, pressure and velocity data were acquired using a dual-tipped pressure and Doppler flow sensor wire (Combowire; Phillips Volcano), and processed offline using customized Matlab software (MathWorks). Patients with low cardiac output underwent dobutamine challenge. Twenty patients with PHLHD (all heart failure with reduced left ventricular ejection fraction) were studied. Right ventricular systole produced a forward compression wave (FCW), followed by a forward decompression wave (FDW) during diastole. Wave reflection manifesting as backward compression wave (BCW) following the FCW was observed in 14 patients. Compared to patients without BCW, patients with BCW had higher mean pulmonary artery pressure (28.7 ± 6.12 vs. 38.6 ± 6.5 mmHg, p = 0.005), and lower pulmonary arterial capacitance (PAC: 2.88 ± 1.75 vs. 1.73 ± 1.16, p = 0.002). Pulmonary vascular resistance was comparable. Mean pulmonary artery pressure of 34.5 mmHg (area under the curve [AUC]: 0.881) and PAC of 2.29 mL/mmHg (AUC: 0.833) predicted BCW. The magnitude of the FCW increased with dobutamine (n = 11) and correlated with pulmonary artery wedge pressure. Wave reflection in PHLHD is more likely at higher pulmonary artery pressures and lower PAC and the magnitude of reflected waves correlated with pulmonary artery wedge pressure. Dobutamine increased FCW but did not affect wave reflection.

Development of a quality of life measure for left ventricular assist device recipients using a mixed methods approach.

BACKGROUND: Left ventricular assist device (LVAD) recipients report symptom improvement but find adjusting to life with the LVAD challenging. These challenges are unique, and existing patient-reported outcome measures (PROMs) do not reflect their experiences. This study aimed to develop a culturally relevant quality of life PROM for use with LVAD recipients in future research, design evolutions and clinical practice. METHODS: A three-stage mixed-methods approach was used to develop a PROM: stage 1 included group concept mapping (GCM); stage 2 semi-structured qualitative interviews were conducted with 11 LVAD recipients and 10 clinicians, and a questionnaire was developed using a conceptual framework; and stage 3 used exploratory psychometric analysis of the PROM data using Rasch measurement theory. This paper presents stages 2 and 3. RESULTS: The conceptual framework consisted of four key concepts, including general health, life with the LVAD, equipment and clothing and emotional impact. Statements from interviews and GCM were used to create items for the LVAD quality of life (LVAD-QoL). Cognitive interviews tested face validity and participant comprehension. Forty-nine participants were recruited from three UK transplant centres. PROM data were collected and analysed using Rasch analysis. Four items displayed misfit; dependency between item sets was the biggest issue (57/485 pairwise differences). After restructuring and dealing with item misfit, the LVAD-QoL conformed to the Rasch model, supporting the psychometric properties and quality of the LVAD-QoL. CONCLUSIONS: Using a mixed-methods approach ensured the development of a robust and psychometrically sound tool for research, design evolution and clinical practice with LVAD recipients.

Consensus statements from the International Society for Heart and Lung Transplantation consensus conference: Heart failure-related cardiogenic shock.

The last decade has brought tremendous interest in the problem of cardiogenic shock. However, the mortality rate of this syndrome approaches 50%, and other than prompt myocardial revascularization, there have been no treatments proven to improve the survival of these patients. The bulk of studies have been in patients with acute myocardial infarction, and there is little evidence to guide the clinician in those patients with heart failure cardiogenic shock (HF-CS). An International Society for Heart and Lung Transplant consensus conference was organized to better define, diagnose, and manage HF-CS. There were 54 participants (advanced heart failure and interventional cardiologists, cardiothoracic surgeons, critical care cardiologists, intensivists, pharmacists, and allied health professionals) with vast clinical and published experience in CS, representing 42 centers worldwide. This consensus report summarizes the results of a premeeting survey answered by participants and the breakout sessions where predefined clinical issues were discussed to achieve consensus in the absence of robust data. Key issues discussed include systems for CS management, including the "hub-and-spoke" model vs a tier-based network, minimum levels of data to communicate when considering transfer, disciplines that should be involved in a "shock team," goals for mechanical circulatory support device selection, and optimal flow on such devices. Overall, the document provides expert consensus on some important issues facing practitioners managing HF-CS. It is hoped that this will clarify areas where consensus has been reached and stimulate future research and registries to provide insight regarding other crucial knowledge gaps.