Step by step daily management of short-term mechanical circulatory support for cardiogenic shock in adults in the intensive cardiac care unit. A clinical consensus statement of the Association for Acute Cardio Vascular Care (ACVC) of the ESC, the European Society of Intensive Care Medicine (ESICM), the European branch of the Extracorporeal Life Support Organization (EuroELSO) and the European Association for Cardio-Thoracic Surgery (EACTS)

Beyond one-size-fits-all in cardiogenic shock: impella, extracorporeal membrane oxygenation or tailored use of mechanical circulatory support?

PURPOSE OF REVIEW

This article offers an overview of recent randomized controlled trials (RCTs) testing the efficacy of veno-arterial extracorporeal membrane oxygenation (VA ECMO) and microaxial flow pump (mAFP) in treating cardiogenic shock, including findings from the DanGer shock trial. It summarizes the clinical implications and limitations of these studies and key decision-making considerations for cardiogenic shock device use.

RECENT FINDINGS

Despite important limitations in all published RCTs, the routine use of VA ECMO for acute myocardial infarction related cardiogenic shock did not demonstrate benefit and should be reserved for selected patients with extreme forms of cardiogenic shock. Conversely, mAFP (Impella CP) appears promising for cardiogenic shock due to ST elevation myocardial infarction. A stepwise approach - initial mAFP use for cardiogenic shock with left ventricular failure, supplemented by VA ECMO if mAFP is inadequate or if severe right ventricular failure is present - may be preferable, but requires validation through RCTs. High complication rates in device arms underscore the need for careful patient selection, preventive strategies, education for centers and operators, and further research.

SUMMARY

Recent trials offer insights into mechanical circulatory support in cardiogenic shock, but their real-world applicability is limited. Despite potential benefits, the use of VA ECMO and mAFP is associated with significant complication rates, emphasizing the need for personalized use.

Differential Hypoxia Risk in Cardiopulmonary Arrest Patients Undergoing Veno-Arterial Extracorporeal Membrane Oxygenation and IMPELLA Support

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a therapeutic strategy for managing cardiogenic shock. However, it carries the risk of cardiogenic pulmonary edema, potentially leading to differential hypoxia. Although IMPELLA can mitigate pulmonary congestion, the combination of VA-ECMO and IMPELLA has frequently resulted in differential hypoxia, requiring a transition from VA-ECMO to veno-arteriovenous extracorporeal membrane oxygenation (VAV-ECMO). Therefore, this study aimed to examine the influence of IMPELLA on the incidence of differential hypoxia, necessitating a shift to VAV-ECMO. This single-center, retrospective, observational study included patients who experienced cardiopulmonary arrest and received treatment with VA-ECMO combined with an intra-aortic balloon pump (IABP) or IMPELLA between 2017 and 2022. The primary endpoint assessed the incidence of differential hypoxia, necessitating a switch to VAV-ECMO. Patients with cardiopulmonary arrest received treatment with VA-ECMO in combination with IABP (N = 28) or IMPELLA (N = 29). There was a significant increase in differential hypoxia 96 hours post-VA-ECMO initiation in the IMPELLA group, necessitating a transition to VAV-ECMO. The combination of VA-ECMO and IMPELLA in patients experiencing cardiopulmonary arrest may significantly increase the risk of differential hypoxia. A multidisciplinary approach employing mechanical circulatory support is crucial, with ongoing consideration of the potential risks associated with differential hypoxia.

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.

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

BACKGROUND

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.

METHODS

Recent guidelines, randomized trials, and registry data underscore the importance of lung-protective ventilation during respiratory and cardiac support on ECMO.

RESULTS

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 >10 mm 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.

CONCLUSION

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.

Mechanical circulatory support for cardiogenic shock: a network meta-analysis of randomized controlled trials and propensity score-matched studies

PURPOSE

Cardiogenic shock is associated with high mortality. In refractory shock, it is unclear if mechanical circulatory support (MCS) devices improve survival. We conducted a network meta-analysis to determine which MCS devices confers greatest benefit.

METHODS

We searched MEDLINE, Embase, and Scopus databases through 27 August 2023 for relevant randomized controlled trials (RCTs) and propensity score-matched studies (PSMs). We conducted frequentist network meta-analysis, investigating mortality (either 30 days or in-hospital) as the primary outcome. We assessed risk of bias (Cochrane risk of bias 2.0 tool/Newcastle-Ottawa Scale) and as sensitivity analysis reconstructed survival data from published survival curves for a one-stage unadjusted individual patient data (IPD) meta-analysis using a stratified Cox model.

RESULTS

We included 38 studies (48,749 patients), mostly reporting on patients with Society for Cardiovascular Angiography and Intervention shock stages C-E cardiogenic shock. Compared with no MCS, extracorporeal membrane oxygenation with intra-aortic balloon pump (ECMO-IABP; network odds ratio [OR]: 0.54, 95% confidence interval (CI): 0.33-0.86, moderate certainty) was associated with lower mortality. There were no differences in mortality between ECMO, IABP, microaxial ventricular assist device (mVAD), ECMO-mVAD, centrifugal VAD, or mVAD-IABP and no MCS (all very low certainty). Our one-stage IPD survival meta-analysis based on the stratified Cox model found only ECMO-IABP was associated with lower mortality (hazard ratio, HR, 0.55, 95% CI 0.46-0.66).

CONCLUSION

In patients with cardiogenic shock, ECMO-IABP may reduce mortality, while other MCS devices did not reduce mortality. However, this must be interpreted within the context of inter-study heterogeneity and limited certainty of evidence.

Improvement of persistent anuria in severe myocardial infarction: the potential role of Impella 5.5 as a bridge to decision

A man in his 40s with ST-segment elevation myocardial infarction complicating cardiogenic shock was transferred to our hospital. Emergent percutaneous coronary intervention for the left anterior descending and left circumflex arteries supported with Impella CP was performed. However, his cardiac function was severely impaired, and anuria developed, necessitating continuous renal replacement therapy (CRRT). After Impella CP was removed on day 6, the patient remained dependent on inotropes and CRRT. Following volume reduction to manage pulmonary congestion, symptoms of low perfusion appeared. Then, Impella 5.5 was inserted on day 38 as a bridge to decision. On day 52, the urine volume reached >2000 mL/day, and CRRT was discontinued. On day 56, the patient was transferred to a certified facility for left ventricular assist device implantation or heart transplantation. This case suggests the potential of Impella 5.5 as a bridge to decision in patients with organ failure caused by low cardiac output.

Mechanical circulatory support in cardiogenic shock

Cardiogenic shock is a complex and diverse pathological condition characterized by reduced myocardial contractility. The goal of treatment of cardiogenic shock is to improve abnormal hemodynamics and maintain adequate tissue perfusion in organs. If hypotension and insufficient tissue perfusion persist despite initial therapy, temporary mechanical circulatory support (t-MCS) should be initiated. This decade sees the beginning of a new era of cardiogenic shock management using t-MCS through the accumulated experience with use of intra-aortic balloon pump (IABP) and venoarterial extracorporeal membrane oxygenation (VA-ECMO), as well as new revolutionary devices or systems such as transvalvular axial flow pump (Impella) and a combination of VA-ECMO and Impella (ECPELLA) based on the knowledge of circulatory physiology. In this transitional period, we outline the approach to the management of cardiogenic shock by t-MCS. The management strategy involves carefully selecting one or a combination of the t-MCS devices, taking into account the characteristics of each device and the specific pathological condition. This selection is guided by monitoring of hemodynamics, classification of shock stage, risk stratification, and coordinated management by the multidisciplinary shock team.

Modelling and Simulation of the Combined Use of IABP and Impella as a Rescue Procedure in Cardiogenic Shock: An Alternative for Non-Transplant Centres?

The treatment of critically ill patients remains an evolving and controversial issue. Mechanical circulatory support through a percutaneous approach for the management of cardiogenic shock has taken place in recent years. The combined use of IABP and the Impella 2.5 device may have a role to play for this group of patients. A simulation approach may help with a quantitative assessment of the achievable degree of assistance. In this paper, we analyse the interaction between the Impella 2.5 pump applied as the LVAD and IABP using the numerical simulator of the cardiovascular system developed in our laboratory. Starting with pathological conditions reproduced using research data, the simulations were performed by setting different rotational speeds for the LVAD and driving the IABP in full mode (1:1) or partial mode (1:2, 1:3 and 1:4). The effects induced by drug administration during the assistance were also simulated. The haemodynamic parameters under investigation were aa follows: mean aortic pressure, systolic and diastolic aortic pressure, mean pulmonary arterial pressure, mean left and right atrial pressure, cardiac output, cardiac index, left and right ventricular end-systolic volume, left ventricular end-diastolic volume and mean coronary blood flow. The energetic variables considered in this study were as follows: left and right ventricular external work and left and right atrial pressure-volume area. The outcome of our simulations shows that the combined use of IABP and Impella 2.5 achieves adequate support in the acute phase of cardiogenic shock compared to each standalone device. This would allow further stabilisation and transfer to a transplant centre should the escalation of treatment be required.

Monitoring MCS patients on the intensive care unit: integrating haemodynamic assessment, laboratory data, and imaging techniques for timely detection of deterioration and recovery

Monitoring of the patient supported with a temporary mechanical circulatory support (tMCS) is crucial in achieving the best possible outcome. Monitoring is a continuous and labour-intensive process, as cardiogenic shock (CS) patients can rapidly deteriorate and may require new interventions within a short time period. Echocardiography and invasive haemodynamic monitoring form the cornerstone of successful tMCS support. During monitoring, it is particularly important to ensure that adequate end-organ perfusion is achieved and maintained. Here, we provide a comprehensive overview of best practices for monitoring the CS patient supported by a micro-axial flow pump, veno-arterial extracorporeal membrane oxygenation, and both devices simultaneously (ECMELLA approach). It is a complex process that encompasses device control, haemodynamic control and stabilization, monitoring of interventions, and assessment of end-organ function. The combined, continuous, and preferably protocol-based approach of echocardiography, evaluation of biomarkers, end-organ assessment, and haemodynamic parameters is crucial in assessing this critically ill CS patient population.

[Place du ballon de contre pulsion intra aortique dans l'infarctus aigu du myocarde compliqué par état de choc cardiogénique]

BACKGROUND AND METHODS

Cardiogenic shock remains one of the leading causes of death in patients with myocardial infarction. The Intra-aortic balloon pump (IABP) has been widely used as a treatment for acute myocardial infarction (AMI), despite recommendations against its routine use. In this paper, our aim is to analyze and share our own experience with IABP in the setting of AMI. We retrospectively reviewed the files of patients admitted with AMI and cardiogenic shock and for whom IABP was inserted between June 2016 and December 2022.

RESULTS

300 patients with AMI and cardiogenic shock were admitted and benefited from IABP insertion and primary coronary revascularization. The overall mortality rate was 62.3%, the site related complication rate was 0.6%, and the overall complications rate (including site related and major bleeding) was 10.6%. There was a significantly higher mortality in the group of patients where the Left Anterior Descending artery (LAD) was the culprit lesion, in the group of patients who required dialysis, the group who had creatinine levels greater than 200 um/L compared to the group who had creatinine lower than 200 um/L, and in patients older than 70 years. Interestingly, no difference in mortality was observed between men and women, single versus multiple vessel disease, and between STEMI and non-STEMI patients.

CONCLUSION

Mortality of AMI complicated by cardiogenic shock and treated by IABP remains high. However, IABP usage is associated with a low complication rate. Better selection criteria for IABP usage versus other more powerful mechanical circulatory support devices in such patients might improve the outcome for the patient.