Predicting Parameters for Successful Weaning from Veno-Arterial Extracorporeal Membrane Oxygenation in Cardiogenic Shock

Predictors of successful weaning from veno-arterial extracorporeal membrane oxygenation (V-A ECMO): A systematic review and meta-analysis

BACKGROUND

Venoarterial extracorporeal membrane oxygenation (V-A ECMO) use to support patients in cardiac failure is increasing. Despite this increased use, predicting successful weaning from ECMO can be challenging, no uniform guidelines on weaning exist. Therefore, we completed a systematic review to evaluate prognostic factors that predict successful weaning from V-A ECMO.

METHODS

Following the PRIMSA guidelines, a systematic literature search of Medline, Embase, SCOPUS and CENTRAL identified original research studies of patients requiring V-A ECMO where weaning was attempted. Data was collected on demographic factors and weaning protocol, biomarkers, haemodynamic, echocardiographic factors for the successfully weaned (SW) and not successfully weaned (NSW) groups. Two investigators reviewed studies for relevance, extracted data, and assessed risk of bias using the ROBINS-I tool. The study was registered on the international prospective register of systematic reviews (PROSPERO ID# CRD42022366153).

RESULTS

1219 records were screened, of which 20 studies were deemed sufficient to be included in the statistical analysis based on pre-specified criteria. Factors associated with successful weaning were higher left ventricular ejection fraction (LVEF) (MD 9.0, 95% CI 4.1-13.8; p < 0.001) and left ventricular outflow tract velocity time integral (LVOT VTI) at time of weaning, (MD 1.35, 95% CI 0.28-2.40 lactate at admission (MD -3.2, 95% CI -4.8 to -1.5, p < 0.001), and CK-MB at admission (MD -4.11, 95%CI -6.6 to -1.6, p = 0.001). Critical appraisal demonstrated moderate-high risk of bias owing to confounding and low sample sizes.

CONCLUSION

In patients on V-A ECMO support being assessed for weaning multi-parametric assessment is required. Moderate-high heterogeneity and low sample sizes warrant higher-quality studies to help guide decisions to wean patients from V-A ECMO.

Echography monitoring in patients with temporary mechanical circulatory support

PURPOSE OF REVIEW

To examine the role of echocardiography in managing patients with refractory cardiogenic shock supported by temporary mechanical circulatory support (t-MCS) and provide practical recommendations to improve clinical practice.

RECENT FINDINGS

t-MCS devices are increasingly used to stabilize patients with refractory cardiogenic shock. Echocardiography, due to its accessibility and ability to assess both structural and functional aspects of heart failure, is ideally suited for daily bedside evaluation of cardiac function and t-MCS-myocardial interactions.

SUMMARY

From t-MCS initiation to liberation, echocardiography is essential to guide clinical decision-making. It aids in selecting the most appropriate t-MCS device, ensuring optimal positioning, and fine-tuning flow parameters in real-time based on native cardiac function and patient needs. Additionally, echocardiography is critical for identifying intracardiac complications and directing unloading strategies in venoarterial extracorporeal membrane oxygenation, particularly with very low residual ejection or aortic valve closure. Finally, the weaning process should be informed by comprehensive echocardiographic evaluations, aligned with international guidelines. These steps are outlined in this review, accompanied by clear and practical recommendations to enhance clinical practice.

Clinical Prediction Score for Successful Liberation from Temporary Mechanical Circulatory Support in Cardiogenic Shock Patients

BACKGROUND

In cardiogenic shock (CS) patients requiring temporary mechanical circulatory support (tMCS), assessing cardiac recovery vs the need for heart replacement therapy is critical. We developed and validated a new clinical score aimed at predicting successful tMCS liberation.

METHODS

A cohort of 80 CS patients treated with Impella support between January 2018 and December 2020 was analyzed. Hemodynamic, echocardiographic, and laboratory data were collected at baseline, 24 hours, 48 hours, and 96 hours after device insertion. Patients were classified as successfully or unsuccessfully liberated from tMCS, based on recovery vs progression to death, left ventricular assist device implantation, or heart transplant. The W score, derived using independent predictors of successful liberation, was validated in 2 cohorts: 86 CS patients at our center and 23 patients from an external center.

RESULTS

Among the 80 patients (mean age 62.5 ± 11.8 years, 63.7% acute myocardial infarction CS), 47.5% achieved successful tMCS liberation. Independent predictors included left ventricular ejection fraction, N-terminal pro-brain natriuretic peptide, and inotropic score at 24 hours, along with creatinine and lactate at 96 hours (area under the curve [AUC] ≥ 0.7, P < 0.05). The W score, using a cutoff of ≥7, demonstrated good diagnostic accuracy (AUC 0.92, sensitivity 80%, specificity 85%, P < 0.001). In validation cohorts, a score ≥7 predicted successful liberation with AUCs of 0.80 (P < 0.001) and 0.72 (P < 0.015) at the internal and external centers, respectively.

CONCLUSIONS

The W score, based on key parameters at 24 and 96 hours post-tMCS, effectively supports clinicians in identifying CS patients likely to achieve successful tMCS liberation.

Sex Differences in Patients With Cardiogenic Shock Receiving Venoarterial Extracorporeal Membrane Oxygenation

BACKGROUND AND OBJECTIVES

Limited data are available on sex differences in clinical outcomes of patients with profound cardiogenic shock (CS) receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO). Therefore, our study sought to compare clinical pictures and outcomes between male and female patients treated with VA-ECMO.

METHODS

A total of 1,328 patients receiving VA-ECMO were selected from either the Samsung Medical Center or a multicenter CS registry named the SMART RESCUE study. The study population was divided into men (n=903) and women (n=425). The primary outcome was in-hospital mortality, and the secondary outcome was procedure-related complications, which included limb ischemia, extracorporeal membrane oxygenation (ECMO) site bleeding and infection, and wound dehiscence.

RESULTS

There was no significant difference in in-hospital mortality (men vs. women, 46.4% vs. 45.6%; adjusted odds ratio [OR], 0.78; 95% confidence interval [CI], 0.58-1.05; p=0.106) based on multivariable analysis. Women showed higher rates of procedure-related complication than men (18.7% vs. 25.9%; adjusted OR, 1.82; 95% CI, 1.29-2.57; p=0.001) mainly driven by higher incidence of limb ischemia (7.1% vs. 12.9%; adjusted OR, 2.32; 95% CI, 1.42-3.78; p=0.001) On multivariable logistic regression analysis, female sex was an independent predictor of procedure-related complications (adjusted OR, 1.68; 95% CI, 1.13-2.49; p=0.009).

CONCLUSIONS

Although no significant difference in either in-hospital or mid-term mortality was found between men and women, female sex is an independent factor for ECMO-related complications.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02985008.

Treatment time limit for successful weaning from veno-arterial extracorporeal membrane oxygenation in cardiogenic shock

AIMS

Knowing the upper time limit for successful weaning from temporary mechanical circulatory support in cardiogenic shock will help with decision-making regarding advanced heart failure (HF) therapy or considering withdrawal of care. The aim of this study was to investigate the association between the support duration and successful weaning from veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in patients with cardiogenic shock.

METHODS AND RESULTS

A retrospective single-centre cohort study was conducted between January 2013 and June 2023. It included 100 consecutive patients with cardiogenic shock who were treated with VA-ECMO. Patients with out-of-hospital cardiac arrest were excluded. The primary outcome was successful weaning from VA-ECMO (i.e., VA-ECMO decannulation and survival to discharge). The association between the length of support duration and the weaning success rate was analysed. Patients were divided into three groups according to ECMO support duration: Group A (≤7 days), Group B (8-14 days), and Group C (≥15 days). Multivariable logistic regression analysis was used to evaluate the impact of the length of support duration on successful weaning of VA-ECMO. The median age was 67 years, and 73% of study participants were male. The underlying aetiologies of cardiogenic shock were as follows: acute myocardial infarction, 50; fulminant myocarditis, 19; cardiomyopathy, 15; valvular heart disease, 8; and other, 8. Seventy-five patients (75%) were attempted to wean VA-ECMO, and 67 moved on to decannulation. In total, 43 (43%) patients were successfully weaned from VA-ECMO. The median length of ECMO support duration was 8 [3-15] days. Compared with those who underwent successful ECMO decannulation, those who did not had a significantly longer support duration of VA-ECMO (5 [3-9] days vs. 12 [3-22] days, P = 0.004). The weaning success rate was significantly higher in patients with short support duration; 58% (29/50), 40% (10/25), 16% (4/25) in Groups A, B, and C, respectively (P = 0.002). Overall, none of the patients supported for over 24 days (0/11) were successfully weaned from VA-ECMO. On multivariable logistic regression analysis, the length of support duration was independently associated with successful weaning after adjusting for age, sex, underlying aetiology, and left ventricular ejection fraction (odds ratio, 0.813 [per 3 days]; 95% confidence interval, 0.679-0.914; P = 0.025).

CONCLUSIONS

Long support duration of VA-ECMO was significantly associated with a low rate of successful weaning in patients with cardiogenic shock. Patients who require VA-ECMO for over 1 week should start considering advanced HF therapy or withdrawal of care.

Imaging in acute percutaneous mechanical circulatory support in adults: a clinical consensus statement of the Association for Acute CardioVascular Care (ACVC) of the ESC, the European Association of Cardiovascular Imaging (EACVI) of the ESC and the European branch of the Extracorporeal Life Support Organization (EuroELSO)

The use of temporary mechanical circulatory support (tMCS) in cardiogenic shock patients has increased during the last decades with most management strategies relying on observational studies and expert opinion, including hemodynamic monitoring, device selection, and timing of support institution/duration. In this context, imaging has a pivotal role throughout the patient pathway, from identification to initiation, monitoring, and weaning. This manuscript summarizes the consensus of an expert panel from the European Society of Cardiology Association for Acute CardioVascular Care, the European Association of CardioVascular Imaging, and the European Extracorporeal Life Support Organization, providing the rationale for and practical guidance of imaging to tMCS based on existing evidence and consensus on best current practice.

Wavelet and time-based cerebral autoregulation analysis using diffuse correlation spectroscopy on adults undergoing extracorporeal membrane oxygenation therapy

INTRODUCTION

Adult patients who have suffered acute cardiac or pulmonary failure are increasingly being treated using extracorporeal membrane oxygenation (ECMO), a cardiopulmonary bypass technique. While ECMO has improved the long-term outcomes of these patients, neurological injuries can occur from underlying illness or ECMO itself. Cerebral autoregulation (CA) allows the brain to maintain steady perfusion during changes in systemic blood pressure. Dysfunctional CA is a marker of acute brain injury and can worsen neurologic damage. Monitoring CA using invasive modalities can be risky in ECMO patients due to the necessity of anticoagulation therapy. Diffuse correlation spectroscopy (DCS) measures cerebral blood flow continuously, noninvasively, at the bedside, and can monitor CA. In this study, we compare DCS-based markers of CA in veno-arterial ECMO patients with and without acute brain injury.

METHODS

Adults undergoing ECMO were prospectively enrolled at a single tertiary hospital and underwent DCS and arterial blood pressure monitoring during ECMO. Neurologic injuries were identified using brain computerized tomography (CT) scans obtained in all patients. CA was calculated over a twenty-minute window via wavelet coherence analysis (WCA) over 0.05 Hz to 0.1 Hz and a Pearson correlation (DCSx) between cerebral blood flow measured by DCS and mean arterial pressure.

RESULTS

Eleven ECMO patients who received CT neuroimaging were recruited. 5 (45%) patients were found to have neurologic injury. CA indices WCOH, the area under the curve of the WCA, were significantly higher for patients with neurological injuries compared to those without neurological injuries (right hemisphere p = 0.041, left hemisphere p = 0.041). %DCSx, percentage of time DCSx was above a threshold 0.4, were not significantly higher (right hemisphere p = 0.268, left hemisphere p = 0.073).

CONCLUSION

DCS can be used to detect differences in CA for ECMO patients with neurological injuries compared to uninjured patients using WCA.

Factors Influencing Successful Weaning From Venoarterial Extracorporeal Membrane Oxygenation: A Systematic Review

With advancements in extracorporeal life support (ECLS) technologies, venoarterial extracorporeal membrane oxygenation (VA-ECMO) has emerged as a crucial cardiopulmonary support mechanism. This review explores the significance of VA-ECMO system configuration, cannulation strategies, and timing of initiation. Through an analysis of medication management strategies, complication management, and comprehensive preweaning assessments, it aims to establish a multidimensional evaluation framework to assist clinicians in making informed decisions regarding weaning from VA-ECMO, thereby ensuring the safe and effective transition of patients.

A novel echocardiographic parameter considering left ventricular afterload during V-A ECMO support

BACKGROUND

Left ventricular stroke work index (LVSWI) and cardiac power index (CPI) account for the haemodynamic load of the left ventricle and are promising prognostic values in cardiogenic shock. However, accurately and non-invasively measuring these parameters during veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is challenging and potentially biased by the extracorporeal circulation. This study aimed to investigate, in an ovine model of cardiogenic shock, whether Pressure-Strain Product (PSP), a novel speckle-tracking echocardiography parameter, (1) can correlate with pressure-volume catheter-based LVSWI and CPI, and (2) can be load-independent during the flow modification of V-A ECMO.

METHODS

Nine Dorset-cross ewes (51 ± 4 kg) were included. After cardiogenic shock was induced, full support V-A ECMO (X L/min based on 60 mL/kg/min) commenced. At seven time points during 24-h observation, echocardiographic parameters as well as pressure-volume catheter-based LVSWI and CPI were simultaneously measured with X and following X-1 L/min of ECMO flow. PSP was calculated by multiplying global circumferential strain or global radial strain, and mean arterial pressure, for PSPcirc or PSPrad, respectively.

RESULTS

PSPcirc showed a stronger correlation with LVSWI (correlation coefficient, CC = .360, p < .001) and CPI (CC = .283, p < .001) than other echocardiographic parameters. The predictability of PSPcirc for pressure-volume catheter-based LVSWI (AUC .82) and CPI (AUC .80) was also higher than other echocardiographic parameters. No statistically significant differences were identified between the two ECMO flow variations in PSPcirc (p = .558).

CONCLUSIONS

A novel echocardiographic parameter, PSP, may non-invasively predict pressure-volume catheter-based LVSWI and CPI in a load-independent manner in a cardiogenic shock supported by V-A ECMO.

Ultrasound vector flow imaging during veno-arterial extracorporeal membrane oxygenation in a thoracic aorta model

In veno-arterial extracorporeal membrane oxygenation (VA-ECMO) treatment, the mixing zone is a key hemodynamic factor that determines the efficacy of the treatment. This study aimed to evaluate the applicability of a novel ultrasound technique called vector flow imaging (VFI) for visualizing complex flow patterns in an aorta phantom under VA-ECMO settings. VFI experiments were performed to image aortic hemodynamics under VA-ECMO treatment simulated in an anthropomorphic thoracic aorta phantom using a pulsatile pump (cardiac output: 2.7 L/min) and an ECMO pump with two different flow rates, 0.35 L/min and 1.0 L/min. The cardiac cycle of hemodynamics in the ascending aorta, aortic arch, and descending aorta was visualized, and the spatio-temporal dynamics of flow vectors were analyzed. VFI successfully visualized dynamic flow patterns in the aorta phantom. When the flow rate of the ECMO pump increased, ECMO flow was more dominant than cardiac output in the diastole phase, and the speed of cardiac output was suppressed in the systole phase. Vortex flow patterns were also detected in the ascending aorta and the arch under both ECMO flow rate conditions. The VFI technique may provide new insights into aortic hemodynamics and facilitates effective and safe VA-ECMO treatment.

Assessment of cardiac load-responsiveness in veno-arterial extracorporeal life support: A case series

INTRODUCTION

Well-timed explant of veno-arterial extracorporeal life support (V-A ECLS) depends on adequate assessment of cardiac recovery. Often, evaluation of cardiac recovery consists of reducing support flow while visualizing cardiac response using transoesophageal echocardiography (TEE). This method, however, is time consuming and based on subjective findings. The dynamic filling index (DFI) may aid in the quantitative assessment of cardiac load-responsiveness. The dynamic filling index is based on the relationship of support flow and pump speed, which varies with varying hemodynamic conditions. This case series intends to investigate whether the DFI may support TEE in facilitating the assessment of cardiac load-responsiveness.

METHODS

Measurements for DFI-determination were performed in seven patients while simultaneously assessing ventricular function by measuring the aortic velocity time integral (VTI) using TEE. Measurements consisted of multiple consecutive transient speed manipulations (∼100 r/min) during weaning trials, both at full support and during cardiac reloading at reduced support.

RESULTS

The VTI increased between full and reduced support in six weaning trials. In five of these trials DFI decreased or remained equal, and in one case DFI increased. Of the three trials in which VTI decreased between full and reduced support, DFI increased in two cases and decreased in one case. Changes in DFI, however, are mostly smaller than the detection threshold of 0.4 mL/rotation.

CONCLUSION

Even though current level of accuracy of the parameter requires further investigation to increase reliability and possibly predictability, DFI seems likely to be a potential parameter in supporting TEE for the assessment of cardiac load-responsiveness.

A Novel Predictive Score Model for Successful Weaning From Mechanical Circulatory Support in Patients With Cardiogenic Shock

BACKGROUND

Clinical evidence regarding predictors of successful weaning from mechanical circulatory support (MCS) is lacking. This study aimed to create a simple risk score to predict successful weaning from MCS in patients with cardiogenic shock.

METHODS AND RESULTS

This retrospective single-center cohort study included 114 consecutive patients with cardiogenic shock treated with venoarterial extracorporeal membrane oxygenation or IMPELLA between January 2013 and June 2023. Patients with out-of-hospital cardiac arrest were excluded. The primary end point was successful weaning from MCS, defined as successful decannulation without the need for MCS reimplantation and survival to discharge. Multivariable logistic regression with a stepwise variable selection was performed to generate the prediction model. We first developed a general weaning score model, and then created a simple version of the score model using the same variables. Fifty-five patients were weaned from MCS successfully. The following variables measured during weaning evaluation were selected as the components of the weaning score model: acute myocardial infarction (AMI), mean blood pressure, left ventricular ejection fraction (LVEF), lactate level, and QRS duration. According to the results, we conducted a novel weaning score model to predict successful weaning from MCS: 1.774 - 2.090 × (AMI) + 0.062 × [mean blood pressure (mm Hg)] + 0.139 × [LVEF (%)] - 0.322 × [Lactate (mg/dL)] - 0.066 × [QRS (ms)]. The following variables were selected as the components of the simple version of the weaning score model: AMI, mean blood pressure of ≥80 mm Hg, lactate of <10 mg/dL, QRS duration of ≤95 ms, and LVEF of >35%.

CONCLUSIONS

We developed a simple model to predict successful weaning from MCS in patients with cardiogenic shock.

Current Use and Impact of Pulmonary Artery Catheters on the Short-Term Outcomes in Patients With Cardiogenic Shock Treated With an Impella: Findings From the Japan Registry for Percutaneous Ventricular Assist Device (J-PVAD)

OBJECTIVES

This study aimed to investigate the current use and impact of pulmonary artery catheters (PACs) in patients with cardiogenic shock (CS) who underwent Impella support.

DESIGN

This was a prospective multicenter observational study between January 2020 and December 2021 that registered all patients with drug-refractory acute heart failure and in whom the placement of an Impella 2.5, CP, or 5.0 pump was attempted or successful in Japan.

SETTING

Cardiac ICUs in Japan.

PATIENTS

Between January 2020 and December 2021, a total of 3112 patients treated with an Impella were prospectively enrolled in the Japan registry for percutaneous ventricular assist device (J-PVAD). Among them, 2063 patients with CS were divided into two groups according to the PAC use.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary endpoint was the 30-day mortality, and the secondary endpoints were hemolysis, acute kidney injury, sepsis, major bleeding unrelated to the Impella, and ventricular arrhythmias within 30 days. PACs were used in 1358 patients (65.8%) who underwent an Impella implantation. The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) was significantly higher in the patients with PACs than in those without. Factors associated with PAC use were the prevalence of hypertension, out-of-hospital cardiac arrest, New York Heart Association classification IV, the lesser prevalence of a heart rate less than 50, and the use of any catecholamine. The primary and secondary endpoints did not significantly differ according to the PAC use. Focusing on the patients with VA-ECMO use, the 30-day mortality and hemolysis were univariately lower in the patients with PACs.

CONCLUSIONS

The J-PVAD findings indicated that PAC use did not have a significant impact on the short-term outcomes in CS patients undergoing Impella support. Further prospective studies are required to explore the clinical implications of PAC-guided intensive treatment strategies in these patients.

Head-to-toe bedside ultrasound for adult patients on extracorporeal membrane oxygenation

Bedside ultrasound represents a well-suited diagnostic and monitoring tool for patients on extracorporeal membrane oxygenation (ECMO) who may be too unstable for transport to other hospital areas for diagnostic tests. The role of ultrasound, however, starts even before ECMO initiation. Every patient considered for ECMO should have a thorough ultrasonographic assessment of cardiac and valvular function, as well as vascular anatomy without delaying ECMO cannulation. The role of pre-ECMO ultrasound is to confirm the indication for ECMO, identify clinical situations for which ECMO is not indicated, rule out contraindications, and inform the choice of ECMO configuration. During ECMO cannulation, the use of vascular and cardiac ultrasound reduces the risk of complications and ensures adequate cannula positioning. Ultrasound remains key for monitoring during ECMO support and troubleshooting ECMO complications. For instance, ultrasound is helpful in the assessment of drainage insufficiency, hemodynamic instability, biventricular function, persistent hypoxemia, and recirculation on venovenous (VV) ECMO. Lung ultrasound can be used to monitor signs of recovery on VV ECMO. Brain ultrasound provides valuable diagnostic and prognostic information on ECMO. Echocardiography is essential in the assessment of readiness for liberation from venoarterial (VA) ECMO. Lastly, post decannulation ultrasound mainly aims at identifying post decannulation thrombosis and vascular complications. This review will cover the role of head-to-toe ultrasound for the management of adult ECMO patients from decision to initiate ECMO to the post decannulation phase.

Clinical decision making for VA ECMO weaning in patients with cardiogenic shock A formative qualitative study

Weaning and liberation from VA ECMO in cardiogenic shock patients comprises a complex process requiring a continuous trade off between multiple clinical parameters. In the absence of dedicated international guidelines, we hypothesized a great heterogeneity in weaning practices among ECMO centers due to a variety in local preferences, logistics, case load and individual professional experience. This qualitative study focused on the appraisal of clinicians' preferences in decision processes towards liberation from VA ECMO after cardiogenic shock while using focus group interviews in 4 large hospitals. The goal was to provide novel and unique insights in daily clinical weaning practices. As expected, we found we a great heterogeneity of weaning strategies among centers and professionals, although participants appeared to find common ground in a clinically straightforward approach to assess the feasibility of ECMO liberation at the bedside. This was shown in a preference for robust, easily accessible parameters such as arterial pulse pressure, stable cardiac index ≥2.1 L/min, VTI LVOT and 'eyeballing' LVEF.

Patient-centered weaning from venoarterial extracorporeal membrane oxygenation: "A practice-oriented narrative review of literature"

Venoarterial extracorporeal membrane oxygenation (V-A ECMO) is increasingly used in cardiogenic shock for rapid stabilization and bridging towards recovery, long-term mechanical circulatory support or transplant. Although technological advances have instigated its widespread use, the complex, long-lasting ECMO care creates a significant strain on hospital staff and resources. Therefore, optimal clinical management including timely decisions on ECMO removal and further therapy are pivotal, yet require a well-structured weaning approach. Although dedicated guidelines are lacking, a variety of weaning protocols have distillated echocardiographic and hemodynamic predictors for successful weaning. Nevertheless, a strikingly high mortality up to 70% after initial successful weaning raises concerns about the validity of current weaning strategies. Here, we plead for a patient-tailored approach including a bailout strategy when weaning fails. This should account not only for left- but also right ventricular function and interdependence, as well as the temporal course of cardiac recovery in function of extracorporeal support. Patients with a high risk of weaning failure should be identified early, enabling timely transportation to an advanced heart failure center. This review summarizes predictors of successful weaning and discusses all relevant elements for a structured weaning approach with a central role for patient-specific clinical considerations and echocardiography.

Extracorporeal Membrane Oxygenation in Postcardiotomy Cardiogenic Shock

Postcardiotomy extracorporeal membrane oxygenation (PC-ECMO), the most frequent indication for ECMO in the United States, is increasingly used as the first-line mechanical circulatory support in patients who are refractory to conventional treatment. Despite increasing use of PC-ECMO, limited evidence is available regarding its safety, efficacy, and optimal timing for initiation and weaning. The decision to use PC-ECMO often is made in the absence of robust clinical data, leading to variability in patient selection, management, and outcomes across different institutions. This article summarizes current evidence on ECMO use in postcardiotomy cardiogenic shock and discusses its potential benefits, management, complications, and outcomes.

Parameters associated with successful weaning of veno-arterial extracorporeal membrane oxygenation: a systematic review

PURPOSE

Veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) can be used to restore organ perfusion in patients with cardiogenic shock until native heart recovery occurs. It may be challenging, however, to determine when patients can be weaned successfully from ECMO-surviving without requiring further mechanical support or heart transplant. We aimed to systematically review the medical literature to determine the biomarkers, hemodynamic and echocardiographic parameters associated with successful weaning of VA-ECMO in adults with cardiogenic shock and to present an evidence-based weaning algorithm incorporating key findings.

METHOD

We systematically searched PubMed, Embase, ProQuest, Google Scholars, Web of Science and the Grey literature for pertinent original research reports. We excluded studies limited to extracorporeal cardiopulmonary resuscitation (ECPR) as the neurological prognosis may significantly alter the decision-making process surrounding the device removal in this patient population. Studies with a mixed population of VA-ECMO for cardiogenic shock or cardiac arrest were included. We excluded studies limited to patients in which ECMO was only used as a bridge to VAD or heart transplant, as such patients are, by definition, never "successfully weaned." We used the Risk of Bias Assessment tool for Non-Randomized Studies. The study was registered on the International prospective register of systematic reviews (PROSPERO CRD42020178641).

RESULTS

We screened 14,578 records and included 47 that met our pre-specified criteria. Signs of lower initial severity of shock and myocardial injury, early recovery of systemic perfusion, left and right ventricular recovery, hemodynamic and echocardiographic stability during flow reduction trial and/or pump-controlled retrograde trial off predicted successful weaning. The most widely used parameter was the left ventricular outflow tract velocity time integral, an indicator of stroke volume. Most studies had a moderate or high risk of bias. Heterogeneity in methods, timing, and conditions of measurements precluded any meta-analysis.

CONCLUSIONS

In adult patients on VA-ECMO for cardiogenic shock, multiple biomarkers, hemodynamic and echocardiographic parameters may be used to track resolution of systemic hypoperfusion and myocardial recovery in order to identify patients that can be successfully weaned.

The ABCDE approach to difficult weaning from venoarterial extracorporeal membrane oxygenation

Venoarterial extracorporeal membrane oxygenation (VA ECMO) has been increasingly applied in patients with cardiogenic shock in recent years. Nevertheless, many patients cannot be successfully weaned from VA ECMO support and 1-year mortality remains high. A systematic approach could help to optimize clinical management in favor of weaning by identifying important factors in individual patients. Here, we provide an overview of pivotal factors that potentially prevent successful weaning of VA ECMO. We present this through a rigorous approach following the relatable acronym ABCDE, in order to facilitate widespread use in daily practice.

Predictors of weaning failure in case of VA ECMO implantation

The use of veno-arterial extracorporeal membrane oxygenation (VA ECMO) for the treatment of refractory cardiogenic shock has increased significantly. Nevertheless, early weaning may be advisable to reduce the potential for severe complications. Only a few studies focusing on ECMO weaning predictors are currently available. Our objective was to evaluate factors that may help predict failure during VA ECMO weaning. We included 57 patients on VA ECMO support previously considered suitable for weaning based on specific criteria. Clinical, haemato-chemical and echocardiographic assessment was considered before and after a "weaning test" (ECMO flow < 2 L/min for at least 60 min). ECMO removal was left to the discretion of the medical team blinded to the results. Weaning failure was defined as a patient who died or required a new VA ECMO, heart transplant or LVAD 30 days after ECMO removal. Thirty-six patients (63.2%) were successfully weaned off VA ECMO, of whom 31 (54.4%) after the first weaning test. In case of first test failure, 3 out of 7 patients could be weaned after a 2nd test and 3 out of 4 patients after a 3rd test. Pre-existing ischemic heart disease (OR 9.6 [1.1-83]), pre-test left ventricular ejection fraction (LVEF) ≤ 25% and/or post-test LVEF ≤ 40% (OR 11 [0.98-115]), post-test systolic blood pressure ≤ 120 mmHg (OR 33 [3-385]), or length of ECMO support > 7 days (OR 24 [2-269]) were predictors of weaning failure. The VA ECMO weaning test failed in less than 40% of patients considered suitable for weaning. Clinical and echocardiographic criteria, which are easily accessible by a non-expert intensivist, may help increase the probability of successful weaning.

Continuous improvement of both hepatic and cardiac dysfunction by sequential plasma exchange in a patient with thyrotoxicosis and cardiogenic shock: a case report indicating the potential role of cardiohepatic interactions during thyroid storm

Background

Thyroid storm (TS) complicated by cardiogenic shock is associated with high mortality due to the high incidence of multiple organ failure. It is recommended that TS patients with hepatic failure undergo plasma exchange (PE) and receive optimal anti-hyperthyroid medications. However, the effect of PE on cardiac dysfunction in TS patients has been unclear.

Case summary

A 46-year-old woman was admitted to our hospital for dyspnoea and tachycardia. She was diagnosed with TS pursuant to Graves' disease complicated by acute decompensated heart failure (ADHF). Cardiac function was remarkably impaired [left ventricular ejection fraction (LVEF) = 15-20%], with rapid atrial fibrillation. Despite the management of both ADHF and hyperthyroidism, cardiogenic shock developed; therefore, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and intra-aortic balloon pumping (IABP) were initiated. Plasma exchange was performed after severe hepatic failure manifested on Day 2. After the first three PE treatments, cardiac and hepatic function improved immediately but deteriorated the next day. The improvement persisted after the fourth PE, and the patient was weaned from VA-ECMO and IABP on Days 10 and 11, respectively. She was discharged on Day 37, and her cardiac function was still normal 1.5 years later.

Discussion

In hyperthyroidism, severe hepatic dysfunction is more likely to occur in patients with acute ADHF than in those without it. Plasma exchange has the potential to improve not only hepatic but also cardiac dysfunction under optimal antithyroid treatment, especially in patients with TS complicated by severe hepatic dysfunction.

Cause of In-Hospital Death After Weaning from Venoarterial-Extracorporeal Membrane Oxygenation

PURPOSE

A survival gap between weaning from venoarterial-extracorporeal membrane oxygenation (VA-ECMO) and the hospital discharge has been consistently reported. The aim of this study is to investigate the clinical features of patients who underwent successful VA-ECMO decannulation at our institution and to identify the major contributors responsible for adverse outcomes.

METHODS

We retrospectively reviewed all patients supported with VA-ECMO in our institution between January 2013 and June 2020. Only patients that survived VA-ECMO and underwent successful decannulation were included and dichotomized based on survival to hospital discharge: non-survivors versus survivors. The primary study outcome was the cause of death after successful VA-ECMO decannulation.

RESULTS

Of the 262 adult patients who underwent VA-ECMO decannulation, 72 (27.5%) patients did not survive to hospital discharge. Non-survivors were older (62 vs. 54 years, p < 0.001) and suffering from many pre-existing comorbidities. Pneumonia and sepsis were the most frequent infectious complication and almost twice as likely in non-survivors. Major causes of death were: cardiovascular (31.9%), infections (25.0%) and neurological (20.8%). The survival curve demonstrated that 51.4% of our patients died within 8 days after decannulation. Multivariate analysis identified older age, central venous cannulation, pulmonary bleeding and infection, dialysis after VA-ECMO, sepsis, and ischemic stroke (OR = 7.86, 95% CI: 2.76-2.43, p < 0.001) as factors significantly predisposing to patients' death.

CONCLUSION

In our study, one-third of patients decannulated off VA-ECMO did not survive to hospital discharge due to end-stage heart failure, infections or neurological injury. The first 8 post-decannulation days were recognized as a critical period where thorough strategies to prevent acquired infections and cautious support of end-organ function should be warranted. Future large-scale trials are needed to confirm our results.

Hemodynamic assessment and risk classification for successful weaning of Impella in patients with cardiogenic shock

BACKGROUND

Clinical predictors for successful weaning of patients from Impella heart pump have not been clarified. We aimed to elucidate the relationship between pulmonary artery catheter (PAC) parameters at the time of Impella weaning and subsequent outcomes.

METHODS

We enrolled consecutive patients who had received Impella for cardiogenic shock. PAC data were collected immediately before Impella weaning. Patients were classified as non-survivors if they died or required any mechanical circulatory support reintroduction within 30 days of weaning.

RESULTS

Of 81 patients enrolled, 61 underwent Impella weaning. Of these, 16 were non-survivors. Predictive indicators of non-survival were high pulmonary artery wedge pressure (PAWP; hazard ratio [HR] per 5 mmHg 1.97, 95% CI 1.35-2.80; p < 0.001), high mean pulmonary artery pressure (MPAP; HR per 5 mmHg 1.90, 1.38-2.58; p < 0.001), and low cardiac power output (CPO; HR per 0.1 Watts 0.71, 0.52-0.92; p = 0.006). Cutoff values of PAWP 20 mmHg, MPAP 22 mmHg, and CPO 0.59 Watts showed strong associations with 30-day non-survival risk (low risk 8% in patients with low PAWP and high CPO or 4% in patients with low MPAP and high CPO; high risk 100% in patients with high PAWP and low CPO or 82% in patients with high MPAP and low CPO).

CONCLUSIONS

PAWP or MPAP higher than the cutoff with CPO below the cutoff at Impella weaning were associated with worse outcomes. We proposed a risk classification model for successful Impella weaning using PAC.

Ultrasound Assessment in Cardiogenic Shock Weaning: A Review of the State of the Art

Cardiogenic shock (CS) is associated with a high in-hospital mortality despite the achieved advances in diagnosis and management. Invasive mechanical ventilation and circulatory support constitute the highest step in cardiogenic shock therapy. Once established, taking the decision of weaning from such support is challenging. Intensive care unit (ICU) bedside echocardiography provides noninvasive, immediate, and low-cost monitoring of hemodynamic parameters such as cardiac output, filling pressure, structural disease, congestion status, and device functioning. Supplemented by an ultrasound of the lung and diaphragm, it is able to provide valuable information about signs suggesting a weaning failure. The aim of this article was to review the state of the art taking into account current evidence and knowledge on ICU bedside ultrasound for the evaluation of weaning from mechanical ventilation and circulatory support in cardiogenic shock.

Hemodynamic monitoring in cardiogenic shock

PURPOSE OF REVIEW

Cardiogenic shock remains a major cause of mortality today. With recent advancements in invasive mechanical support strategies, reperfusion practice, and a new classification scheme is proposed for cardiogenic shock, an updated review of the latest hemodynamic monitoring techniques is important.

RECENT FINDINGS

Multiple recent studies have emerged supporting the use of pulmonary artery catheters in the cardiogenic shock population. Data likewise continues to emerge on the use of echocardiography and biomarker measurement in the care of these patients.

SUMMARY

The integration of multiple forms of hemodynamic monitoring, spanning noninvasive and invasive modalities, is important in the diagnosis, staging, initial treatment, and subsequent management of the cardiogenic shock patient.