Percutaneous left-heart decompression during extracorporeal membrane oxygenation: an alternative to surgical and transeptal venting in adult patients

Novel Left Ventricular Unloading Strategies in Patients on Peripheral Venoarterial Extracorporeal Membrane Oxygenation Support

The purpose of this study was to evaluate left ventricular (LV) unloading strategies in patients supported with peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO). A retrospective review was conducted of all consecutive patients requiring VA-ECMO support for any indication, who underwent novel LV unloading strategies with either direct left atrial venoarterial (LAVA) cannulation or pulmonary artery venoarterial (PAVA) venting, in comparison to Impella and intra-aortic balloon pump (IABP). The primary outcome was successful bridge to transplant, LV assist device, or myocardial recovery. Forty-six patients (63% male, mean age 52.8 ± 17.6 years) were included. Fourteen patients (30%) underwent novel unloading with either LAVA or PAVA, 11 patients (24%) underwent IABP placement, and 21 patients (46%) underwent Impella insertion. In the novel LV unloading cohort, 10 patients (71%) survived to hospital discharge. Four patients (29%) were weaned from ECMO and eight patients (57%) underwent cardiac transplantation. Although a trend favoring cannula-based unloading for the primary outcome was noted, the cohort was too small for statistical significance (79% LAVA/PAVA, 57% Impella, 45% IABP; p = 0.21). However, probability of survival was greater in the LAVA/PAVA cohort compared to Impella and IABP ( p < 0.05). Thus, we demonstrate the efficacy of LA and PA cannulation as an alternative LV unloading strategy for patients supported with peripheral VA-ECMO.

Unloading the Left Ventricle in Venoarterial ECMO: In Whom, When, and How?

Venoarterial extracorporeal membrane oxygenation provides cardiorespiratory support to patients in cardiogenic shock. This comes at the cost of increased left ventricle (LV) afterload that can be partly ascribed to retrograde aortic flow, causing LV distension, and leads to complications including cardiac thrombi, arrhythmias, and pulmonary edema. LV unloading can be achieved by using an additional circulatory support device to mitigate the adverse effects of mechanical overload that may increase the likelihood of myocardial recovery. Observational data suggest that these strategies may improve outcomes, but in whom, when, and how LV unloading should be employed is unclear; all techniques require balancing presumed benefits against known risks of device-related complications. This review summarizes the current evidence related to LV unloading with venoarterial extracorporeal membrane oxygenation.

Emerging concepts in heart failure management and treatment: circulatory support with extracorporeal membrane oxygenation (ECMO)

Circulatory support with extracorporeal membrane oxygenation (ECMO) is being increasingly used in several critical situations but evidence of its impact on outcomes is inconsistent. Understanding of the specific indications and appropriate timing of implantation of this technology might lead to improved results. Indeed, the line between success and futility may be sometimes very thin when facing a patient in critical condition. New techniques with lighter, simpler and effective devices are being developed. Hence, ECMO has become an accessible technology that is being increasingly used outside of the operating room by heart failure specialists, critical care cardiologists and intensivists. Proper timing of utilization and choice of device may lead to better outcomes. We herein aim to improve this knowledge gap by conducting a literature review to provide simple information, evidence-based indications and a practical approach for cardiologists who may encounter acutely ill adult patients that may be ECMO candidates. This article is part of the Emerging concepts in heart failure management and treatment Special Issue: https://www.drugsincontext.com/special_issues/emerging-concepts-in-heart-failure-management-and-treatment.

Role of percutaneous pulmonary artery cannulation in extracorporeal life support for acute cardiac failure: A single-center case series

BACKGROUND

Pulmonary artery (PA) cannulation is an effective extracorporeal life support (ECLS) management for left ventricular (LV) decompression or right ventricular (RV) support. This case series explores the results of PA cannulation during ECLS for acute cardiac failure.

METHODS

Patients receiving percutaneous PA cannulation between January 2017 and December 2020 in a single institution were retrospectively reviewed. Patients receiving PA cannulation by a surgical cutdown method were excluded. Based on the hemodynamic needs of the patients, percutaneous PA cannulation was applied with ECLS for LV unloading and/or RV support. The primary endpoint was the successful weaning from circulatory support. The secondary endpoints included 30-day or in-hospital mortality, significant periprocedural complications, and successful hospital discharge without major complications.

RESULTS

Fifteen patients (13 men, age range 11.2-70.8 years) presented acute heart failure and were initially managed by conventional ECLS mode. Percutaneous PA cannulation was performed for LV unloading in 13 patients (86.67%) and isolated RV circulatory support in two patients (13.33%). Weaning from circulatory support was achieved in 11 patients (73.33%). No significant periprocedural complication, including bleeding, infection, or vascular event requiring surgical exploration, was reported. The 30-day or in-hospital mortality rate was 33.33%. Eight cases (53.33%) were successfully discharged without major complications, including permanent stroke or the need for long-term hemodialysis.

CONCLUSIONS

PA cannulation, especially percutaneously performed, was effective and safe for LV unloading and/or RV support during ECLS. Further investigation is required to confirm the efficacy and safety of our approach and management in a larger patient population.

Venting during venoarterial extracorporeal membrane oxygenation

Cardiogenic shock and cardiac arrest contribute pre-dominantly to mortality in acute cardiovascular care. Here, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has emerged as an established therapeutic option for patients suffering from these life-threatening entities. VA-ECMO provides temporary circulatory support until causative treatments are effective and enables recovery or serves as a bridging strategy to surgical ventricular assist devices, heart transplantation or decision-making. However, in-hospital mortality rate in this treatment population is still around 60%. In the recently published ARREST trial, VA-ECMO treatment lowered mortality rate in patients with ongoing cardiac arrest due to therapy refractory ventricular fibrillation compared to standard advanced cardiac life support in selected patients. Whether VA-ECMO can reduce mortality compared to standard of care in cardiogenic shock has to be evaluated in the ongoing prospective randomized studies EURO-SHOCK (NCT03813134) and ECLS-SHOCK (NCT03637205). As an innate drawback of VA-ECMO treatment, the retrograde aortic flow could lead to an elevation of left ventricular (LV) afterload, increase in LV filling pressure, mitral regurgitation, and elevated left atrial pressure. This may compromise myocardial function and recovery, pulmonary hemodynamics—possibly with concomitant pulmonary congestion and even lung failure—and contribute to poor outcomes in a relevant proportion of treated patients. To overcome these detrimental effects, a multitude of venting strategies are currently engaged for both preventive and emergent unloading. This review aims to provide a comprehensive and structured synopsis of existing venting modalities and their specific hemodynamic characteristics. We discuss in detail the available data on outcome categories and complication rates related to the respective venting option.

Graphical abstract

Left ventricular venting in veno-arterial extracorporeal membrane oxygenation: A computer simulation study

INTRODUCTION

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is the fastest way to restore circulation in refractory cardiogenic shock, however it cannot unload the failing left ventricle. There is a lack of consensus regarding optimal approach to left ventricular venting in V-A ECMO patients with severely depressed or absent left ventricular function.

METHODS

A computer model was developed in Matlab Simulink R20016b (MathWorks, Inc., Natick, MA, USA) to analyze different venting options as well as atrial septostomy in the setting of cardiogenic shock and V-A ECMO.

RESULTS

The model has shown an inverse linear relationship between left atrial pressure and either vent, Impella or atrial septum defect flow rate. The minimum vent flow required to prevent pulmonary edema in complete loss of left ventricular function needed to be higher than the bronchial blood flow. Atrial septostomy restored normal pulmonary blood flow with low left atrial pressure but induced stasis in the left ventricle. Venting the pulmonary artery induced stasis in the entire pulmonary circulation as well as left atrium and left ventricle. Venting the left ventricle directly with a cannula or Impella device avoided blood stasis.

CONCLUSION

Our data suggest that reduction of left atrial pressure is linearly related to the vent, Impella or atrial septal defect flow rate. The preferred vent location is the left ventricle as it avoids stasis in the pulmonary circulation and cardiac chambers.

Novel method for left ventricular unloading utilizing percutaneous pulmonary artery drainage in cardiorespiratory failure due to COVID-19 infection

Left ventricular (LV) unloading is an important concept in patients undergoing peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO). We present a case of a 32-year-old male in acute cardiorespiratory collapse due to coronavirus disease (COVID-19) who underwent VA-ECMO cannulation in the setting of cardiogenic shock and acute respiratory distress syndrome. Due to inability to utilize percutaneous LV assist device (pLVAD) for LV unloading due to small end diastolic dimension, alternative strategies were explored. A traditionally utilized right ventricular support device, the ProTek Duo (TandemLife, Pittsburgh, PA), was utilized to drain the pulmonary artery, leading to improvement in parameters for cardiogenic shock. To our knowledge, this is the first case in which a ProTek Duo has been utilized in conjunction with VA-ECMO to provide LV unloading in support of a patient in cardiogenic shock. This method can be employed in future challenging situations where pLVAD is not feasible.

Use of Transcarotid IMPELLA 2.5 Axial-Flow Pump Device for Left Ventricle Unloading During VA-ECMO Support in Pediatric Acute Heart Failure

An alternative strategy for left ventricular (LV) venting during short-term mechanical circulatory support is use of Impella axial-flow pump. We present our transcarotid Impella 2.5 implantation technique using a polytetrafluoroethylene graft, in two children with acute heart failure treated primarily with venoarterial ECMO. The venoarterial extracorporeal membrane oxygenator and Impella support were maintained for 5 and 17 days, respectively. Transcarotid Impella implantation might be an alternative and feasible option in pediatrics patients affected by severe LV failure, as a bridge to decision or bridge to candidacy. Potentially, the Impella 2.5 device provides less invasive support for children with heart failure.

Comparison of Circulatory Unloading Techniques for Venoarterial Extracorporeal Membrane Oxygenation

Left ventricular (LV) distention and pulmonary congestion are major complications inherent to venoarterial extracorporeal membrane oxygenation (ECMO). This study aimed to quantitatively compare the hemodynamic differences between common circulatory unloading methods for ECMO. Ten circulatory unloading techniques were evaluated on a mock circulatory loop simulating acute LV failure supported by ECMO. Simulated unloading techniques included: surgical and percutaneous pulmonary artery (PA) venting, surgical left atrial venting, surgical and percutaneous LV venting, atrial septal defect, partial support ventricular assist device, intraaortic balloon pump, and temporary VAD with inline oxygenator (tVAD). The most LV unloading occurred with the surgically placed LV vent and tVAD, which reduced LV end-diastolic volume from 295 to 167 ml and 82 ml, respectively. Meanwhile, the PA surgical vent was the most effective at reducing mean PA pressure from 21.0 to 10.6 mm Hg, and the tVAD was most effective at reducing left atrial pressure from 13.3 to 4.4 mm Hg. The major limitation of this study was the use of a mock circulatory loop, which simulated lower left atrial pressure than is typically seen clinically. This study identified clinically significant hemodynamic variability between the different circulatory unloading techniques evaluated. However, the applicability of these techniques will vary with different patient disease etiology. Further studies on ECMO unloading will help to quantify hemodynamic benefits and establish treatment guidelines.

2020 EACTS/ELSO/STS/AATS Expert Consensus on Post-cardiotomy Extracorporeal Life Support in Adult Patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management and avoidance of complications, appraisal of new approaches and ethics, education and training.

Comparison of left ventricular unloading strategies on venoarterial extracorporeal life support

OBJECTIVES

Our goal was to compare the haemodynamic effects of different mechanical left ventricular (LV) unloading strategies and clinical outcomes in patients with refractory cardiogenic shock supported with venoarterial extracorporeal membrane oxygenation (VA-ECMO).

METHODS

A total of 448 patients supported with VA-ECMO for refractory cardiogenic shock between 1 March 2015 and 31 January 2020 were included and analysed in a single-centre, retrospective case-control study. Fifty-three patients (11.8%) on VA-ECMO required LV unloading. Percutaneous balloon atrial septostomy (PBAS), intra-aortic balloon pump (IABP) and transapical LV vent (TALVV) strategies were compared with regards to the composite rate of death, procedure-related complications and neurological complications. The secondary outcomes were reduced pulmonary capillary wedge pressure, pulmonary artery pressure, central venous pressure, left atrial diameter and resolution of pulmonary oedema on a chest X-ray within 48 h.

RESULTS

No death related to the LV unloading procedure was detected. Reduction in pulmonary capillary wedge pressure was highest with the TALVV technique (17.2 ± 2.1 mmHg; P < 0.001) and was higher in the PBAS than in the IABP group; the difference was significant (9.6 ± 2.5 and 3.9 ± 1.3, respectively; P = 0.001). Reduction in central venous pressure with TALVV was highest with the other procedures (7.4 ± 1.1 mmHg; P < 0.001). However, procedure-related complications were significantly higher with TALVV compared to the PBAS and IABP groups (50% vs 17.6% and 10%, respectively; P = 0.015). We observed no significant differences in mortality or neurological complications between the groups.

CONCLUSIONS

Our results suggest that TALVV was the most effective method for LV unloading compared with PBAS and IABP for VA-ECMO support but was associated with complications. Efficient LV unloading may not improve survival.

2020 EACTS/ELSO/STS/AATS expert consensus on post-cardiotomy extracorporeal life support in adult patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management, and avoidance of complications, appraisal of new approaches and ethics, education, and training.

Modalities of Left Ventricle Decompression during VA-ECMO Therapy

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is used to sustain circulatory and respiratory support in patients with severe cardiogenic shock or refractory cardiac arrest. Although VA-ECMO allows adequate perfusion of end-organs, it may have detrimental effects on myocardial recovery. Hemodynamic consequences on the left ventricle, such as the increase of afterload, end-diastolic pressure and volume, can lead to left ventricular (LV) distention, increase of myocardial oxygen consumption and delayed LV function recovery. LV distention occurs in almost 50% of patients supported with VA-ECMO and is associated with an increase in morbidity and mortality. Thus, recognizing, preventing and treating LV distention is key in the management of these patients. In this review, we aim to discuss the pathophysiology of LV distention and to describe the strategies to unload the LV in patients supported with VA-ECMO.

Extracorporeal Life Support and Mechanical Circulatory Support in Out-of-Hospital Cardiac Arrest and Refractory Cardiogenic Shock

The prevalence of extracorporeal cardiopulmonary resuscitation is increasing worldwide as more health care centers develop the necessary infrastructure, protocols, and technical expertise required to provide mobile extracorporeal life support with short notice. Strict adherence to patient selection guidelines in the setting of out-of-hospital cardiac arrest, as well as in-hospital cardiac arrest, allows for improved survival with neurologically favorable outcomes in a larger patient population. This review discusses the preferred approaches, cannulation techniques, and available support devices ideal for the various clinical situations encountered during the treatment of cardiac arrest and refractory cardiogenic shock.

A mini-thoracotomy approach for walking veno-arterial extracorporeal membranous oxygenation

Fulminant myocarditis is a rapidly progressive myocardial inflammation that commonly requires advanced circulatory support therapies. We report our management of a 36-year-old gentleman with fulminant myocarditis who we managed with extracorporeal membranous oxygenation (ECMO) and subsequently durable bi-ventricular assist devices as a bridge to heart transplantation. The patient was admitted after a 1-week history of malaise with severe lethargy, jugular venous distension to greater than 10 cm, and troponin elevation to greater than 27 K. He was taken immediately for a heart catheterization which showed no obstructive coronary disease, and hemodynamics consistent with bi-ventricular failure. We proceeded with ECMO for hemodynamic support, utilizing a mini-thoracotomy for cannulation. A Protek Duo Rapid Deployment (LivaNova) was inserted via a modified Seldinger technique through the left ventricular apex, terminating in the ascending aorta. Percutaneous right IJ bicaval via a y-ed Avalon Elite (Getinge) was employed for venous drainage. This case highlights an alternate strategy for central walking veno-arterial ECMO in a patient presenting with fulminant myocarditis with a platform that minimizes upper/lower extremity over/under perfusion complications, while providing sternal sparring antegrade arterial flow with simultaneous ventricular unloading/venting.

Outcomes of left ventricular unloading with a transseptal cannula during extracorporeal membrane oxygenation in adults

We evaluated the benefit of left ventricular (LV) unloading using a percutaneous transseptal left atrial (LA) drain catheter via femoral vein incorporated into the ECMO venous circuit. This single-center retrospective observational study analyzed clinical outcomes of the LA venting group (N = 62) who underwent percutaneous transseptal LA drain placement comparing with the conventionally treated control group (N = 62) with an arterial pulse pressure below 10 mm Hg for at least 24 hours from December 2012 to August 2018. The ECMO weaning rate (61.3% vs. 38.7%, P = .012) and cardiac transplantation rate (29.0% vs. 11.3%, P = .014) were higher in the LA venting group than in the control group. Inhospital mortality was not significantly different (56.5% vs. 69.4%, P = .191). Pulmonary congestion mostly improved after LA decompression (61.3%, P = .003). A serum lactate level at 24 hours after LA venting of more than 2.2 mmol/L was associated with poor outcomes. LA venting via transseptal cannula reduced pulmonary venous congestion and achieved higher rates of successful ECMO weaning and cardiac transplantation. Placement of a transseptal venous drain cannula should be considered in patients with uncontrolled pulmonary edema secondary to severe LV loading undergoing VA-ECMO.

Hemodynamic adaptation of heart failure to percutaneous venoarterial extracorporeal circulatory supports

Extracorporeal life support (ECLS) is a treatment modality that provides prolonged blood circulation, gas exchange and can partially support or fully substitute functions of heart and lungs in patients with severe but potentially reversible cardiopulmonary failure refractory to conventional therapy. Due to high-volume bypass, the extracorporeal flow is interacting with native cardiac output. The pathophysiology of circulation and ECLS support reveals significant effects on arterial pressure waveforms, cardiac hemodynamics, and myocardial perfusion. Moreover, it is still subject of research, whether increasing stroke work caused by the extracorporeal flow is accompanied by adequate myocardial oxygen supply. The left ventricular (LV) pressure-volume mechanics are reflecting perfusion and loading conditions and these changes are dependent on the degree of the extracorporeal blood flow. By increasing the afterload, artificial circulation puts higher demands on heart work with increasing myocardial oxygen consumption. Further, this can lead to LV distention, pulmonary edema, and progression of heart failure. Multiple methods of LV decompression (atrial septostomy, active venting, intra-aortic balloon pump, pulsatility of flow) have been suggested to relieve LV overload but the main risk factors still remain unclear. In this context, it has been recommended to keep the rate of circulatory support as low as possible. Also, utilization of detailed hemodynamic monitoring has been suggested in order to avoid possible harm from excessive extracorporeal flow.

2020 EACTS/ELSO/STS/AATS expert consensus on post-cardiotomy extracorporeal life support in adult patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management and avoidance of complications, appraisal of new approaches and ethics, education and training.

2020 EACTS/ELSO/STS/AATS Expert Consensus on Post-Cardiotomy Extracorporeal Life Support in Adult Patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management and avoidance of complications, appraisal of new approaches and ethics, education and training.

Pulmonary artery cannulation to enhance extracorporeal membrane oxygenation management in acute cardiac failure

OBJECTIVES

Pulmonary artery (PA) cannulation during peripheral venoarterial extracorporeal membrane oxygenation (ECMO) has been shown to be effective either for indirect left ventricular (LV) unloading or to allow right ventricular (RV) bypass with associated gas-exchange support in case of acute RV with respiratory failure. This case series reports the results of such peculiar ECMO configurations with PA cannulation in different clinical conditions.

METHODS

All consecutive patients receiving PA cannulation (direct or percutaneous) from January 2015 to September 2018 in 3 institutions were retrospectively reviewed. Isolated LV unloading or RV support, as well as dynamic support including initial drainage followed by perfusion through the PA cannula, was used as part of the ECMO configuration according to the type of patient and the patient's haemodynamic/functional needs.

RESULTS

Fifteen patients (8 men, age range 45-73 years, EuroSCORE log range 14.45-91.60%) affected by acute LV, RV or biventricular failure of various aetiologies, were supported by this ECMO mode. Percutaneous PA cannulation was performed in 10 patients and direct PA cannulation, in 5 cases. Dynamic ECMO management (initially draining and then perfusing through the PA cannula) was carried out in 6 patients. Mean ECMO duration was 9.1 days (range 6-17 days). One patient exhibited pericardial fluid during the implant of a PA cannula (no lesion found when the chest was opened), and weaning from temporary circulatory support was achieved in 14 patients (1 who received a transplant). Three patients (20%) died in-hospital, and 12 patients were successfully discharged without major complications.

CONCLUSIONS

Effective indirect LV unloading in peripheral venoarterial ECMO as well as isolated RV support can be achieved by PA cannulation. Such an ECMO configuration may allow the counteraction of common venoarterial ECMO shortcomings or allow dynamic/adjustable management of ECMO according to specific ventricular dysfunction and haemodynamic needs. Percutaneous PA cannulation was shown to be safe and feasible without major complications. Additional investigation is needed to confirm the safety and efficacy of such an ECMO configuration and management in a larger patient population.

Left Ventricular Unloading During Veno-Arterial ECMO: A Simulation Study

Supplemental Digital Content is available in the text.

Veno-arterial extracorporeal membrane oxygenation (VA ECMO) is widely used in cardiogenic shock. It provides systemic perfusion, but left ventricular (LV) unloading is suboptimal. Using a closed-loop, real-time computer model of the human cardiovascular system, cardiogenic shock supported by peripheral VA ECMO was simulated, and effects of various adjunct LV unloading interventions were quantified. After VA ECMO initiation (4 L/min) in cardiogenic shock (baseline), hemodynamics improved (increased to 85 mm Hg), while LV overload occurred (10% increase in end-diastolic volume [EDV], and 5 mm Hg increase in pulmonary capillary wedge pressure [PCWP]). Decreasing afterload (65 mm Hg mean arterial pressure) and circulating volume (−800 mL) reduced LV overload (12% decrease in EDV and 37% decrease in PCWP) compared with baseline. Additional intra-aortic balloon pumping only marginally decreased cardiac loading. Instead, adjunct Impella™ enhanced LV unloading (23% decrease in EDV and 41% decrease in PCWP). Alternative interventions, for example, left atrial/ventricular venting, yielded substantial unloading. We conclude that real-time simulations may provide quantitative clinical measures of LV overload, depending on the degree of VA ECMO support and adjunct management. Simulations offer insights into individualized LV unloading interventions in cardiogenic shock supported by VA ECMO as a proof of concept for potential future applications in clinical decision support, which may help to improve individualized patient management in complex cardiovascular disease.

Veno-Arterial Extracorporeal Membrane Oxygenation for Cardiogenic Shock

Extracorporeal membrane oxygenation has evolved, from a therapy that was selectively applied in the pediatric population in tertiary centers, to more widespread use in diverse forms of cardiopulmonary failure in all ages. We provide a practical review for cardiovascular clinicians on the application of veno-arterial extracorporeal membrane oxygenation in adult patients with cardiogenic shock, including epidemiology of cardiogenic shock, indications, contraindications, and the extracorporeal membrane oxygenation circuit. We also summarize cannulation techniques, practical management and troubleshooting, prognosis, and weaning and exit strategies, with attention to end of life and ethical considerations.

Medical Optimization and Liberation of Adult Patients From VA-ECMO

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) can be an efficacious cardiopulmonary support for adults as rescue from refractory cardiogenic shock. It is best employed as a bridging strategy to recovery or alternative support rather than sustained, long-term mechanical circulatory support. The purpose of this paper is to discuss strategies to optimize patient management on VA-ECMO and approaches to promote successful separation from support. Rapid medical optimization will assist in reducing the time on VA-ECMO, thereby improving the likelihood of patient salvage. Suitably trained physicians and personnel, guided by structured protocols, can promote excellence in team care and provision of consistent management. Focusing on anticoagulation, careful neurologic monitoring, prevention of leg ischemia, awareness of differential hypoxemia, optimizing mechanical ventilation, identifying and timely intervention for left-ventricular distension (LVD), along with a strategic weaning algorithm, can prevent significant morbidity and mortality. LVD physiology, diagnosis, and risk factors are reviewed. Indications for LV decompression, along with medical and mechanical management options, are elucidated.

Contemporary Management of Out-of-hospital Cardiac Arrest in the Cardiac Catheterisation Laboratory: Current Status and Future Directions

Out-of-hospital cardiac arrest (OHCA) is an important cause of mortality and morbidity in developed countries and remains an important public health burden. A primary cardiac aetiology is common in OHCA patients, and so patients are increasingly brought to specialist cardiac centres for consideration of coronary angiography, percutaneous coronary intervention and mechanical circulatory support. This article focuses on the management of OHCA in the cardiac catheterisation laboratory. In particular, it addresses conveyance of the OHCA patient direct to a specialist centre, the role of targeted temperature management, pharmacological considerations, provision of early coronary angiography and mechanical circulatory support.

The Extracorporeal Life Support Organization Maastricht Treaty for Nomenclature in Extracorporeal Life Support. A Position Paper of the Extracorporeal Life Support Organization

Extracorporeal life support (ECLS) was developed more than 50 years ago, initially with venoarterial and subsequently with venovenous configurations. As the technique of ECLS significantly improved and newer skills developed, complexity in terminology and advances in cannula design led to some misunderstanding of and inconsistency in definitions, both in clinical practice and in scientific research. This document is a consensus of multispecialty international representatives of the Extracorporeal Life Support Organization, including the North America, Latin America, EuroELSO, South West Asia and Africa, and Asia-Pacific chapters, imparting a global perspective on ECLS. The goal is to provide a consistent and unambiguous nomenclature for ECLS and to overcome the inconsistent use of abbreviations for ECLS cannulation. Secondary benefits are ease of multicenter collaboration in research, improved registry data quality, and clear communication among practitioners and researchers in the field.

Relationship Between Time to Left Atrial Decompression and Outcomes in Patients Receiving Venoarterial Extracorporeal Membrane Oxygenation Support: A Multicenter Pediatric Interventional Cardiology Early-Career Society Study

OBJECTIVES

To assess the variation in timing of left atrial decompression and its association with clinical outcomes in pediatric patients supported with venoarterial extracorporeal membrane oxygenation across a multicenter cohort.

DESIGN

Multicenter retrospective study.

SETTING

Eleven pediatric hospitals within the United States.

PATIENTS

Patients less than 18 years on venoarterial extracorporeal membrane oxygenation who underwent left atrial decompression from 2004 to 2016.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 137 patients (median age, 4.7 yr) were included. Cardiomyopathy was the most common diagnosis (47%). Cardiac arrest (39%) and low cardiac output (50%) were the most common extracorporeal membrane oxygenation indications. Median time to left atrial decompression was 6.2 hours (interquartile range, 3.8-17.2 hr) with the optimal cut-point of greater than or equal to 18 hours for late decompression determined by receiver operating characteristic curve. In univariate analysis, late decompression was associated with longer extracorporeal membrane oxygenation duration (median 8.5 vs 5 d; p = 0.02). In multivariable analysis taking into account clinical confounder and center effects, late decompression remained significantly associated with prolonged extracorporeal membrane oxygenation duration (adjusted odds ratio, 4.4; p = 0.002). Late decompression was also associated with longer duration of mechanical ventilation (adjusted odds ratio, 4.8; p = 0.002). Timing of decompression was not associated with in-hospital survival (p = 0.36) or overall survival (p = 0.42) with median follow-up of 3.2 years.

CONCLUSIONS

In this multicenter study of pediatric patients receiving venoarterial extracorporeal membrane oxygenation, late left atrial decompression (≥ 18 hr) was associated with longer duration of extracorporeal membrane oxygenation support and mechanical ventilation. Although no survival benefit was demonstrated, the known morbidities associated with prolonged extracorporeal membrane oxygenation use may justify a recommendation for early left atrial decompression.

A simulation study of left ventricular decompression using a double lumen arterial cannula prototype during a veno-arterial extracorporeal membrane oxygenation

BACKGROUND

Veno-arterial extracorporeal membrane oxygenation can be vital to support patients in severe or rapidly progressing cardiogenic shock. In cases of left ventricular distension, left ventricular decompression during veno-arterial extracorporeal membrane oxygenation may be a crucial factor influencing the patient outcome. Application of a double lumen arterial cannula for a left ventricular unloading is an alternative, straightforward method for left ventricular decompression during extracorporeal membrane oxygenation in a veno-arterial configuration.

OBJECTIVES

The purpose of this article is to use a mathematical model of the human adult cardiovascular system to analyze the left ventricular function of a patient in cardiogenic shock supported by veno-arterial extracorporeal membrane oxygenation with and without the application of left ventricular unloading using a novel double lumen arterial cannula.

METHODS

A lumped model of cardiovascular system hydraulics has been coupled with models of non-pulsatile veno-arterial extracorporeal membrane oxygenation, a standard venous cannula, and a drainage lumen of a double lumen arterial cannula. Cardiogenic shock has been induced by decreasing left ventricular contractility to 10% of baseline normal value.

RESULTS

The simulation results indicate that applying double lumen arterial cannula during veno-arterial extracorporeal membrane oxygenation is associated with reduction of left ventricular end-systolic volume, end-diastolic volume, end-systolic pressure, and end-diastolic pressure.

CONCLUSIONS

A double lumen arterial cannula is a viable alternative less invasive method for left ventricular decompression during veno-arterial extracorporeal membrane oxygenation. However, to allow for satisfactory extracorporeal membrane oxygenation flow, the cannula design has to be revisited.

Effect of Mean Blood Pressure During Extracorporeal Life Support on Outcome After Out-of-Hospital Cardiac Arrest

Objective

Extracorporeal Life Support (ECLS) can help to improve the outcome of refractory cardiac arrest (CA). ECLS allows to maintain blood pressure and tissue perfusion until the cause of CA is treated. The aim of the present study was to describe the mean blood pressure (MBP) during the first 24 h of ECLS for out-of-hospital CA (OHCA).

Methods

We performed a retrospective analysis of consecutive refractory OHCA requiring ECLS admitted to the intensive care unit. MBP was examined after starting ECLS (H0) and every 6 h during the first 24 h (H6, H12, H18 and H24).

Results

Forty patients were analysed. MBP significantly differs between survivors and non-survivors since 6 h: 77 vs 44 mm Hg (p=0.002), 51 vs 87 mm Hg at H12 (p=0.008), 57 vs 75 mm Hg at H18 (p=0.015) and 79 vs 53 mm Hg at H24 (p=0.004), whereas no difference was observed at H0: 69 vs 55 mm Hg (p=0.06). An MBP lower than 65 mm Hg since 6 h is associated with a poor outcome (sensitivity and specificity of death of 87% and 66% at H6, 80% and 75% at H12, 100% and 75% at H18 and 70% and 80% at H24, respectively).

Conclusion

Despite high levels of catecholamine, the inability to maintain MBP higher than 60 mm Hg after starting ECLS for OHCA is associated with a poor outcome.

Transaortic Left Ventricular Unloading in VA-ECMO: The Transsubclavian Route

Left ventricular unloading during extracorporeal life support aims to minimize potential side effects of increased left ventricular afterload. A transaortic catheter vent implanted through a subclavian approach was used in 2 patients. Patient 1 was a 48-year-old man with a recent history of ST-elevation myocardial infarction who developed refractory cardiogenic shock due to severe biventricular dysfunction. Patient 2 was a 56-year-old man admitted for severe flu. The unloading procedure was successful in both patients, with bridge to heart transplantation in the first case and bridge to recovery in the other.

Efficacy of left heart decompression during extracorporeal membrane oxygenation: a case-control study

Background

Veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) is used in various cardiogenic shocks. In severe myocardial dysfunction, left heart (LH) distension may occur and aggravate pulmonary edema. Despite the recent case reports on various venting catheter insertion methods for LH decompression, the necessity and efficacy of LH venting procedure are still controversial. Therefore, we focused on evaluating efficacy of LH venting catheter insertion for LH decompression.

Methods

In total, 373 patients received VA ECMO at our institution from May 2012 to January 2016. Of these, 25 patients underwent LH venting catheter insertion. Indication for the procedure included pulmonary congestion observed on chest radiogram, with arterial pulse pressure ≤10 mmHg. The control group comprised of 45 patients with peripheral VA ECMO having arterial pulse pressure ≤ for ≥24 hours during the same study period who did not undergo LH venting procedure. Finally, 70 patients were compared and analyzed.

Results

Mean age of the patients was 52.6±17.1 years. The ECMO running time in each group was 7.2±7.1 days in the vent (-) group and 9.2±8.5 days in the vent (+) group. Successful weaning rate was higher in the LH vent (+) group (P=0.08). Moreover, LH venting catheter insertion was identified as a predictor of weaning success with marginal significance (OR =2.47; 95% CI: 0.90-6.72; P=0.07).

Conclusions

LH decompression by venting catheter insertion in patients on VA ECMO may be more effective and helpful for successful ECMO weaning than conventional medical management without survival benefit.

The ELSO Maastricht Treaty for ECLS Nomenclature: abbreviations for cannulation configuration in extracorporeal life support - a position paper of the Extracorporeal Life Support Organization

Background

The Extracorporeal Life Support Organization (ELSO) Maastricht Treaty for Nomenclature in Extracorporeal Life Support (ECLS) established consensus nomenclature and abbreviations for ECLS to ensure accurate, concise communication.

Methods

We build on this consensus nomenclature by layering a framework of precise and efficient abbreviations for cannula configuration that describe flow direction, number of cannulae used, any additional ECLS-related catheters, and cannulation sites. This work is a consensus of international representatives of the ELSO, including those from the North American, Latin American, European, South and West Asian, and Asian-Pacific chapters of ELSO.

Results

The classification increases in descriptive capability by introducing a third (cannula tip position) and fourth (cannula dimension) level to those provided in the previous consensus on ECLS cannulation configuration nomenclature. This expansion offers the simplest level needed to convey cannulation information yet allows for more details when required.

Conclusions

A complete nomenclature for ECLS cannulation configurations accommodating future revisions was developed to facilitate ability to compare practices and results, to promote efficient communication, and to improve quality of registry data.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2334-8) contains supplementary material, which is available to authorized users.

Left ventricular decompression in veno-arterial extracorporeal membrane oxygenation

Background

Despite the survival benefit of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for treatment of refractory cardiogenic shock, it can also have potentially deleterious effects of left ventricular overload and pulmonary edema. The objective of this review was to investigate the current evidence on the incidence, diagnosis, risk factors, prevention, and interventions for left ventricular overload in adult and pediatric VA-ECMO patients.

Methods

Five electronic databases, including MEDLINE, EMBASE, PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Cochrane Database of Systematic Reviews, were searched for original published studies from their dates of inception to January 2018. All types of adult and pediatric studies that investigated LV overload in VA-ECMO and were published in the English language were reviewed. Exclusion criteria included abstracts and conference presentations.

Results

The reported incidence and sequelae of LV overload in VA-ECMO are highly variable, with presentations ranging from pulmonary arterial diastolic pressures of greater than 25 mmHg and LV distention on echocardiography, to severe pulmonary edema, LV thrombosis, and refractory ventricular arrhythmias. Currently, there are no standardized diagnostic criteria or guidelines for the type and timing of intervention for LV overload. Techniques for LV decompression have included direct surgical LV venting with catheter insertion via sternotomy or a minimally invasive incision; percutaneous catheterization via a transaortic, transseptal, or transpulmonary approach; ventricular assist devices; and intra-aortic balloon pumps.

Conclusions

Left ventricular volume distention is a significant problem in VA-ECMO patients, with sequelae including myocardial ischemia, severe pulmonary edema, and intracardiac thrombosis. Further research is required on its incidence, diagnostic criteria, and risk factors, as well as the optimal timing and method for LV decompression, given the diversity of surgical and percutaneous techniques that are available.

Clinical Pearls of Venoarterial Extracorporeal Membrane Oxygenation for Cardiogenic Shock

Extracorporeal membrane oxygenation (ECMO) is a technique that uses a pump to drain blood from a body, circulate blood through a membrane lung, and return the oxygenated blood back into the body. Venoarterial (VA) ECMO is a simplified version of the heart-lung machine that assists native pulmonary and/or cardiac function. VA ECMO is composed of a drainage cannula in the venous system and a return cannula in the arterial system. Because VA ECMO can increase tissue perfusion by increasing the arterial blood flow, it is used to treat medically refractory cardiogenic shock or cardiac arrest. VA ECMO has a distinct physiology that is referred to as differential flows. It can cause several complications such as left ventricular distension with pulmonary edema, distal limb ischemia, bleeding, and thromboembolism. Physicians who are using this technology should be knowledgeable on the prevention and management of these complications. We review the basic physiology of VA ECMO, the mechanism of complications, and the simple management of VA ECMO.

Additional unloading of the left ventricle using the Impella LP 2.5 during extracorporeal life support in cases of pulmonary congestion

Extracorporeal life support (ECLS) is used for the treatment of severe cardiogenic shock. However, pulmonary congestion can progress to a severe problem with ECLS therapy. We report our experience with the Impella system for severe pulmonary congestion with ECLS therapy. We used the Impella system for two patients, which led to successful unloading of the left ventricle. Impella implantation during ECLS support appears to be a promising concept. However, more evidence is required for further evaluation.

Left ventricular unloading during veno-arterial ECMO: a review of percutaneous and surgical unloading interventions

Short-term mechanical support by veno-arterial extracorporeal membrane oxygenation (VA ECMO) is more and more applied in patients with severe cardiogenic shock. A major shortcoming of VA ECMO is its variable, but inherent increase of left ventricular (LV) mechanical load, which may aggravate pulmonary edema and hamper cardiac recovery. In order to mitigate these negative sequelae of VA ECMO, different adjunct LV unloading interventions have gained a broad interest in recent years. Here, we review the whole spectrum of percutaneous and surgical techniques combined with VA ECMO reported to date.

Monitoring during extracorporeal membrane oxygenation

PURPOSE OF REVIEW

An increasing number of patients are placed on extracorporeal membrane oxygenation (ECMO) for respiratory or cardiac failure. Sound understanding of physiology and configuration of ECMO is essential for proper management. This review covers different monitoring parameters and tools for patients supported with different types of ECMO.

RECENT FINDINGS

Emphasis is placed on monitoring saturations at different sites depending on type of ECMO support. The main monitoring tools detailed in this review are echocardiography and pulmonary artery catheters.

SUMMARY

The review will help physicians better assess adequate ECMO support by using the appropriate parameters for each type of configuration.

Modalities and Effects of Left Ventricle Unloading on Extracorporeal Life support: a Review of the Current Literature

INTRODUCTION/AIM

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) support is increasingly used in refractory cardiogenic shock and cardiac arrest, but is characterized by a rise in afterload of the left ventricle (LV) which may ultimately either further impair or delay cardiac contractility improvement. The aim of this study was to provide a comprehensive overview regarding the different LV venting techniques and results currently available in the literature.

METHODS

A systematic literature search was performed in the PubMed database: 207 articles published between 1993 and 2016 were included. Papers dealing with pre-clinical studies, overlapping series, and association with other assist devices were excluded from the review, with 45 published papers finally selected. Heterogeneous indications for LV unloading were reported. The selected literature was divided into subgroups, according to the location or the performed procedure for LV venting.

RESULTS

Case reports or case series accounted for 60% of the papers, while retrospective study represented 29% of them. Adult series were present in 67%, paediatric patients in 29%, and a mixed population in 4%. LV unloading was performed percutaneously in 84% of the cases. The most common locations of unloading was the left atrium (31%), followed by indirect unloading (intra-aortic balloon pump) (27%), trans-aortic (27%), LV (11%), and pulmonary artery (4%). Percutaneous trans-septal approach was reported in 22%. Finally, the unloading was conducted surgically in 16%,with open chest surgery in 71%, and minimally invasive surgery in 29% of surgical cases.

CONCLUSION

Nowadays, only a few data are available about left heart unloading in V-A ECMO support. Despite the well-known controversy, IABP remains widely used in combination with V-A ECMO. Percutaneous approaches utilizing unloading devices is becoming an increasingly used option. However, further studies are required to establish the optimal LV unloading method.

Hybrid extracorporeal membrane oxygenation

Veno-venous (VV) and veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) therapy is widely used in critically ill patients with refractory cardiogenic shock and cardiac arrest or suffering from severe respiratory failure. Besides traditional ECMO cannulation, changes in patients' conditions or the occurrence of specific complications (i.e., cerebral hypoxia or left ventricular dilation) may require modifications in cannulation strategies or the combination of ECMO with additional invasive or minimally invasive procedures, to improve organ function and ECMO efficiency. In this review, we described all these "hybrid" approaches, such as the addition of a third or fourth ECMO cannula to improve venous drainage and/or optimize systemic hemodynamics/oxygenation, or the implementation of surgical or percutaneous unloading of the left ventricle (LV), to reduce cardiac dilation and pulmonary edema. Although few data are still available about the effectiveness of such interventions, clinicians should be aware of these advances in ECMO management to improve the management of more complex cases.

Intra-aortic balloon pump protects against hydrostatic pulmonary oedema during peripheral venoarterial-extracorporeal membrane oxygenation

Background:

Increased left ventricular afterload during peripheral venoarterial-extracorporeal membrane oxygenation (VA-ECMO) support frequently causes hydrostatic pulmonary oedema. Because physiological studies demonstrated left ventricular afterload decrease during VA-ECMO assistance combined with the intra-aortic balloon pump (IABP), we progressively changed our standard practice systematically to associate an IABP with VA-ECMO. This study aimed to evaluate IABP efficacy in preventing pulmonary oedema in VA-ECMO-assisted patients.

Methods:

A retrospective single-centre study.

Results:

Among 259 VA-ECMO patients included, 104 received IABP. Weinberg radiological score-assessed pulmonary oedema was significantly lower in IABP+ than IABP– patients at all times after ECMO implantation. This protection against pulmonary oedema persisted when death and switching to central ECMO were used as competing risks (subhazard ratio 0.49, 95% confidence interval (CI) 0.33–0.75; P<0.001). Multivariable analysis retained IABP as being independently associated with a lower risk of radiological pulmonary oedema (odds ratio (OR) 0.4, 95% CI 0.2–0.7; P=0.001) and a trend towards lower mortality (OR 0.54, 95% CI 0.29–1.01; P=0.06). Finally, the time on ECMO free from mechanical ventilation increased in IABP+ patients (2.2±4.3 vs. 0.7±2.0 days; P=0.0003). Less frequent pulmonary oedema and more days off mechanical ventilation were also confirmed in 126 highly comparable IABP+ and IABP– patients, propensity score matched for receiving an IABP.

Conclusions:

Associating an IABP with peripheral VA-ECMO was independently associated with a lower frequency of hydrostatic pulmonary oedema and more days off mechanical ventilation under ECMO.