Impella Versus Extracorporeal Membrane Oxygenation for Acute Myocardial Infarction Cardiogenic Shock

Impella - Current issues and future expectations for the percutaneous, microaxial flow left ventricular assist device

The importance of temporary mechanical circulatory support for treating acute heart failure with cardiogenic shock is increasingly recognized, and Impella (Abiomed, Danvers, MA, USA) has received particular attention in this regard. Impella is an axial flow left ventricular assist device (LVAD) built into the tip of a catheter. It is inserted via a peripheral artery and implanted into the left ventricle. Although the morphology of Impella is different from a typical LVAD, it has similar actions and effects as an LVAD in terms of left ventricular drainage and aortic blood delivery. Impella increases mean arterial pressure (MAP) and systemic blood flow, thereby improving peripheral organ perfusion and promoting recovery from multiple organ failure. In addition, left ventricular unloading with increased MAP increases coronary perfusion and decreases myocardial oxygen demand, thereby promoting myocardial recovery. Impella is also useful as a mechanical vent of the left ventricle in patients supported with veno-arterial extracorporeal membrane oxygenation. Indications for Impella include emergency use for cardiogenic shock and non-emergent use during high-risk percutaneous coronary intervention and ventricular tachycardia ablation. Its intended uses for cardiogenic shock include bridge to recovery, durable device, heart transplantation, and heart surgery. Prophylactic use of Impella in high-risk patients undergoing open heart surgery to prevent postcardiotomy cardiogenic shock is also gaining attention. While there have been many case reports and retrospective studies on the benefits of Impella, there is little evidence based on sufficiently large randomized controlled trials (RCTs). Currently, several RCTs are now ongoing, which are critical to determine when, for whom, and how these devices should be used. In this review, we summarize the principles, physiology, indications, and complications of the Impella support and discuss current issues and future expectations for the device.

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.

Changing Trends in Mechanical Circulatory Support Use and Outcomes in Patients Undergoing Percutaneous Coronary Interventions for Acute Coronary Syndrome Complicated With Cardiogenic Shock: Insights From a Nationwide Registry in Japan

BACKGROUND

Temporal trends in the management of acute coronary syndrome complicated with cardiogenic shock after the revision of guideline recommendations for intra-aortic balloon pump (IABP) use and the approval of the Impella require further investigation, because their impact remains uncertain.

METHODS AND RESULTS

Using the Japanese Percutaneous Coronary Intervention (J-PCI) registry database from 2019 to 2021, we identified 12 171 patients undergoing percutaneous coronary intervention for acute coronary syndrome complicated with cardiogenic shock under mechanical circulatory support. The patients were stratified into 3 groups: (1) IABP alone, (2) Impella, and (3) venoarterial extracorporeal membrane oxygenation (VA-ECMO); the VA-ECMO group was further stratified into (3a) VA-ECMO alone, (3b) VA-ECMO in combination with IABP, and (3c) VA-ECMO in combination with Impella. The quarterly prevalence and outcomes were reported. The use of IABP alone decreased significantly from 63.5% in the first quarter of 2019 to 58.3% in the fourth quarter of 2021 (P for trend=0.01). Among 4245 patients requiring VA-ECMO, the use of VA-ECMO in combination with IABP decreased significantly from 78.7% to 67.3%, whereas the use of VA-ECMO in combination with Impella increased significantly from 4.2% to 17.0% (P for trend <0.001 for both). After adjusting for the confounders, the risk difference in the fourth quarter of 2021 relative to the first quarter of 2019 for in-hospital mortality was not significant (adjusted odds ratio, 0.84 [95% CI, 0.69-1.01]).

CONCLUSIONS

Our study revealed substantial changes in the use of different mechanical circulatory support modalities in acute coronary syndrome complicated with cardiogenic shock, but they did not significantly improve the outcomes.

Acute coronary syndrome associated cardiogenic shock in the catheterization laboratory: peripheral veno-arterial extracorporeal membrane oxygenator management and recommendations

Cardiogenic shock (CS) in acute coronary syndrome (ACS) is a critical disease with high mortality rates requiring complex treatment to maximize patient survival chances. Emergent coronary revascularization along with circulatory support are keys to saving lives. Mechanical circulatory support may be instigated in severe, yet still reversible instances. Of these, the peripheral veno-arterial extracorporeal membrane oxygenator (pVA-ECMO) is the most widely used system for both circulatory and respiratory support. The aim of our work is to provide a review of our current understanding of the pVA-ECMO when used in the catheterization laboratory in a CS ACS setting. We detail the workings of a Shock Team: pVA-ECMO specifics, circumstances, and timing of implantations and discuss possible complications. We place emphasis on how to select the appropriate patients for potential pVA-ECMO support and what characteristics and parameters need to be assessed. A detailed, stepwise implantation algorithm indicating crucial steps is also featured for practitioners in the catheter laboratory. To provide an overall aspect of pVA-ECMO use in CS ACS we further gave pointers including relevant human resource, infrastructure, and consumables management to build an effective Shock Team to treat CS ACS via the pVA-ECMO method.

Impella and venoarterial extracorporeal membrane oxygenation in cardiogenic shock complicating acute myocardial infarction

AIMS

This study aimed to give contemporary insight into the use of Impella and venoarterial extracorporeal membrane oxygenation (VA-ECMO) in acute myocardial infarction-related cardiogenic shock (AMICS) and into associated outcomes, adverse events, and resource demands.

METHODS AND RESULTS

This nationwide observational cohort study describes all AMICS patients treated with Impella (ABIOMED, Danvers, MA, USA) and/or VA-ECMO in 2020-2021. Impella and/or VA-ECMO were used in 20% of all AMICS cases (n = 4088). Impella patients were older (34% vs. 13% >75 years, p < 0.001) and less frequently presented after an out-of-hospital cardiac arrest (18% vs. 40%, p < 0.001). In-hospital mortality was lower in the Impella versus VA-ECMO cohort (61% vs. 67%, p = 0.001). Adverse events occurred less frequently in Impella-supported patients: acute haemorrhagic anaemia (36% vs. 68%, p < 0.001), cerebrovascular accidents (4% vs. 11%, p < 0.001), thromboembolisms of the extremities (5% vs. 8%, p < 0.001), systemic inflammatory response syndrome (21% vs. 25%, p = 0.004), acute kidney injury (44% vs. 53%, p < 0.001), and acute liver failure (7% vs. 12%, p < 0.001). Impella patients were discharged home directly more often (20% vs. 11%, p < 0.001) whereas VA-ECMO patients were more often discharged to another care facility (22% vs. 19%, p = 0.031). Impella patients had shorter hospital stays and lower hospital costs.

CONCLUSION

This is the largest, most recent European cohort study describing outcomes, adverse events, and resource demands based on claims data in patients with Impella and/or VA-ECMO. Overall, adverse event rates and resource consumption were high. Given the current lack of beneficial evidence, our study reinforces the need for prospectively established, high-quality evidence to guide clinical decision-making.

Acute mechanical circulatory support for cardiogenic shock in India

Cardiogenic shock continues to have high morbidity and mortality, despite advances in the field. Temporary mechanical circulatory support (TMCS) devices, if instituted in a timely fashion, can help stabilize critically ill patients with cardiogenic shock from various aetiologies and cardiac arrest, and provide time for organ recovery or till durable support or transplantation can be achieved. Currently, several options for TMCS devices exist. In this review, we discuss indications, contraindications, characteristics of the various available devices, and important issues pertaining to their management.

Impella Versus VA-ECMO for Patients with Cardiogenic Shock: Comprehensive Systematic Literature Review and Meta-Analyses

Impella and VA-ECMO are two possible therapeutic courses for the treatment of patients with cardiogenic shock (CS). The study aims to perform a systematic literature review and meta-analyses of a comprehensive set of clinical and socio-economic outcomes observed when using Impella or VA-ECMO with patients under CS. A systematic literature review was performed in Medline, and Web of Science databases on 21 February 2022. Nonoverlapping studies with adult patients supported for CS with Impella or VA-ECMO were searched. Study designs including RCTs, observational studies, and economic evaluations were considered. Data on patient characteristics, type of support, and outcomes were extracted. Additionally, meta-analyses were performed on the most relevant and recurring outcomes, and results shown using forest plots. A total of 102 studies were included, 57% on Impella, 43% on VA-ECMO. The most common outcomes investigated were mortality/survival, duration of support, and bleeding. Ischemic stroke was lower in patients treated with Impella compared to the VA-ECMO population, with statistically significant difference. Socio-economic outcomes including quality of life or resource use were not reported in any study. The study highlighted areas where further data collection is needed to clarify the value of complex, new technologies in the treatment of CS that will enable comparative assessments focusing both on the health impact on patient outcomes and on the financial burden for government budgets. Future studies need to fill the gap to comply with recent regulatory updates at the European and national levels.

IABP versus Impella Support in Cardiogenic Shock: “In Silico” Study

Cardiogenic shock (CS) is part of a clinical syndrome consisting of acute left ventricular failure causing severe hypotension leading to inadequate organ and tissue perfusion. The most commonly used devices to support patients affected by CS are Intra-Aortic Balloon Pump (IABP), Impella 2.5 pump and Extracorporeal Membrane Oxygenation. The aim of this study is the comparison between Impella and IABP using CARDIOSIM© software simulator of the cardiovascular system. The results of the simulations included baseline conditions from a virtual patient in CS followed by IABP assistance in synchronised mode with different driving and vacuum pressures. Subsequently, the same baseline conditions were supported by the Impella 2.5 with different rotational speeds. The percentage variation with respect to baseline conditions was calculated for haemodynamic and energetic variables during IABP and Impella assistance. The Impella pump driven with a rotational speed of 50,000 rpm increased the total flow by 4.36% with a reduction in left ventricular end-diastolic volume (LVEDV) by ≅15% to ≅30%. A reduction in left ventricular end systolic volume (LVESV) by ≅10% to ≅18% (≅12% to ≅33%) was observed with IABP (Impella) assistance. The simulation outcome suggests that assistance with the Impella device leads to higher reduction in LVESV, LVEDV, left ventricular external work and left atrial pressure-volume loop area compared to IABP support.

Intervention in Cardiogenic Shock

Cardiogenic shock is characterized by hypotension along with signs of hypoperfusion. It has been defined by various societies and clinical trials in different manner. Acute myocardial infarction is the most common cause of cardiogenic shock. Despite early percutaneous coronary intervention, shock secondary to acute coronary syndrome carries mortality rates reaching up to 40–50%. Mechanical circulatory support has been designed to potentially improve outcomes in such patients, but data remains scarce on mortality benefits and long-term outcomes.

Characteristics and Outcomes of Early vs Late Initiation of Mechanical Circulatory Support in Non-Acute Myocardial Infarction related Cardiogenic Shock: An Analysis of the National Inpatient Sample Database

Cardiogenic shock (CS) is significant cause of mortality. The use of mechanical circulatory support (MCS) in patients with non-acute myocardial infarction (Non-AMI) CS is lacking. We inquired data regarding the trends and outcomes early vs late initiation of MCS in non-AMI CS. We investigated National Inpatient Sample database between October 2015-December 2018, identifying hospitalizations with CS, either complicated by AMI or Non-AMI. Patients were divided into 2 cohorts, early initiation of MCS (<48 hours) and late initiation of MCS (>48 hours). The primary analysis included death within first 24 hours. A secondary analysis was adjusted after excluding patients who died in first 24 hours. A total of 85,318 patients with non-AMI-related CS with MCS placement were identified. Among this cohort, 54.6% (n=46,579) underwent early initiation of MCS within 48 hours, and 45.4% (n=38,739) underwent late initiation of MCS after 48 hours. In primary analysis, early MCS initiation was associated with more in-hospital mortality in primary outcome of all-cause hospital mortality (35.72% vs 27.63%, P<0.0001, OR 1.44, 95% CI: 1.40-1.49, P<0.0001), however, adjusted secondary analysis showed a statistically significant decrease in all-cause hospital mortality (23.63% vs 27.63%, P<0.0001, OR 0.80, 95% CI: 0.78-0.83, P<0.0001). In non-AMI-related CS and based on survival to 24 hours after admission, early initiation of MCS had statistically significant decrease in all-cause hospital mortality, with less incidence of vascular and renal complications, and shorter hospital stay. Late initiation of MCS was associated with a higher incidence of advanced therapies, including LVAD and transplant.

Mechanical Assist Device-Assisted Percutaneous Coronary Intervention: The Use of Impella Versus Extracorporeal Membrane Oxygenation as an Emerging Frontier in Revascularization in Cardiogenic Shock

The extracorporeal membrane oxygenation (ECMO) procedure aids in the provision of prolonged cardiopulmonary support, whereas the Impella device (Abiomed, Danvers, MA) is a ventricular assist device that maintains circulation by pumping blood into the aorta from the left ventricle. Blood is circulated in parallel with the heart by Impella. It draws blood straight into the aorta from the left ventricle, hence preserving the physiological flow. ECMO bypasses the left atrium and the left ventricle, and the end consequence is a non-physiological flow. In this article, we conducted a detailed analysis of various publications in the literature and examined various modalities pertaining to the use of ECMO and Impella for cardiogenic shocks, such as efficacy, clinical outcomes, cost-effectiveness, device-related complications, and limitations. The Impella completely unloads the left ventricle, thereby significantly reducing the effort of the heart. Comparatively, ECMO only stabilizes a patient with cardiogenic shock for a short stretch of time and does not lessen the efforts of the left ventricle ("unload" it). In the acute setting, both devices reduced left ventricular end-diastolic pressure and provided adequate hemodynamic support. By comparing patients on Impella to those receiving ECMO, it was found that patients on Impella were associated with better clinical results, quicker recovery, limited complications, and reduced healthcare costs; however, there is a lack of conclusive studies performed demonstrating the reduction in long-term mortality rates. Considering the effectiveness of given modalities and taking into account the various studies described in the literature, Impella has reported better clinical outcomes although more clinical trials are needed for establishing the effectiveness of these interventional approaches in revascularization in cardiogenic shock.

Prophylactic Impella CP versus VA-ECMO in Patients Undergoing Complex High-Risk Indicated PCI

OBJECTIVES

To compare two different forms of mechanical circulatory support (MCS) in patients with complex high-risk indicated PCI (CHIP): the Impella CP system and veno-arterial extracorporeal membrane oxygenation (VA-ECMO).

BACKGROUND

To prevent hemodynamic instability in CHIP, various MCS systems are available. However, comparable data on different forms of MCS are not at hand.

METHODS

In this multicenter observational study, we retrospectively evaluated all CHIP procedures with the support of an Impella CP or VA-ECMO, who were declined surgery by the heart team. Major adverse cardiac events (MACE), mortality at discharge, and 30-day mortality were evaluated.

RESULTS

A total of 41 patients were included, of which 27 patients were supported with Impella CP and 14 patients with VA-ECMO. Baseline characteristics were well-balanced in both groups. No significant difference in periprocedural hemodynamic instability was observed between both groups (3.7% vs. 14.3%; p = 0.22). The composite outcome of MACE showed no significant difference (30.7% vs. 21.4%; p = 0.59). Bleeding complications were higher in the Impella CP group, but showed no significant difference (22.2% vs. 7.1%; p = 0.22) and occurred more at the non-Impella access site. In-hospital mortality was 7.4% in the Impella CP group versus 14.3% in the VA-ECMO group and showed no significant difference (p = 0.48). 30-Day mortality showed no significant difference (7.4% vs. 21.4%; p = 0.09).

CONCLUSIONS

In patients with CHIP, there were no significant differences in hemodynamic instability and overall MACE between VA-ECMO or Impella CP device as mechanical circulatory support. Based on this study, the choice of either VA-ECMO or Impella CP does not alter the outcome.

IMPELLA VERSUS EXTRACORPOREAL MEMBRANE OXYGENATION IN CARDIOGENIC SHOCK: A SYSTEMATIC REVIEW AND META-ANALYSIS

ABSTRACT

Background: Cardiogenic shock (CS) carries high mortality. The roles of specific mechanical circulatory support (MCS) systems are unclear. We compared the clinical outcomes of Impella versus extracorporal membrane oxygenation (ECMO) in patients with CS. Methods: This is a systematic review and meta-analysis that was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta Analyses guidelines. We searched PubMed, Cochrane Central Register, Embase, Web of Science, Google Scholar, and ClinicalTrials.gov (inception through May 10, 2022) for studies comparing the outcomes of Impella versus ECMO in CS. We used random-effects models to calculate risk ratios (RRs) with 95% confidence interval (CIs). End points included in-hospital, 30-day, and 12-month all-cause mortality, successful weaning from MCS, bridge to transplant, all reported bleeding, stroke, and acute kidney injury. Results: A total of 10 studies consisting of 1,827 CS patients treated with MCS were included in the analysis. The risk of in-hospital all-cause mortality was significantly lower with Impella compared with ECMO (RR, 0.80; 95% CI, 0.65-1.00; P = 0.05), whereas there was no statistically significant difference in 30-day (RR, 0.97, 95% CI, 0.82-1.16; P = 0.77) and 12-month mortality (RR, 0.90; 95% CI, 0.74-1.11; P = 0.32). There were no significant differences between the two groups in terms of successful weaning (RR, 0.97; 95% CI, 0.81-1.15; P = 0.70) and bridging to transplant (RR, 0.88; 95% CI, 0.58-1.35; P = 0.56). There was less risk of bleeding and stroke in the Impella group compared with the ECMO group. Conclusions: In patients with CS, the use of Impella is associated with lower rates of in-hospital mortality, bleeding, and stroke than ECMO. Future randomized studies with adequate sample sizes are needed to confirm these findings.

Microaxial Left Ventricular Assist Device in Cardiogenic Shock: A Systematic Review and Meta-Analysis

Microaxial left ventricular assist devices (LVAD) are increasingly used to support patients with cardiogenic shock; however, outcome results are limited to single-center studies, registry data and select reviews. We conducted a systematic review and meta-analysis, searching three databases for relevant studies reporting on microaxial LVAD use in adults with cardiogenic shock. We conducted a random-effects meta-analysis (DerSimonian and Laird) based on short-term mortality (primary outcome), long-term mortality and device complications (secondary outcomes). We assessed the risk of bias and certainty of evidence using the Joanna Briggs Institute and the GRADE approaches, respectively. A total of 63 observational studies (3896 patients), 6 propensity-score matched (PSM) studies and 2 randomized controlled trials (RCTs) were included (384 patients). The pooled short-term mortality from observational studies was 46.5% (95%-CI: 42.7–50.3%); this was 48.9% (95%-CI: 43.8–54.1%) amongst PSM studies and RCTs. The pooled mortality at 90 days, 6 months and 1 year was 41.8%, 51.1% and 54.3%, respectively. Hemolysis and access-site bleeding were the most common complications, each with a pooled incidence of around 20%. The reported mortality rate of microaxial LVADs was not significantly lower than extracorporeal membrane oxygenation (ECMO) or intra-aortic balloon pumps (IABP). Current evidence does not suggest any mortality benefit when compared to ECMO or IABP.

Impella versus extracorporeal membranous oxygenation (ECMO) for cardiogenic shock: a systematic review and meta-analysis

BACKGROUND

The use of mechanical circulatory support (MCS) in cardiogenic shock (CS) is increasing. We conducted a systematic review and meta-analysis to compare outcomes with the Impella device vs. ECMO in patients with CS.

METHODS

We searched the Medline, EMBASE, Cochrane, and Clinicaltrials.gov databases for observational studies comparing Impella to ECMO in patients with CS. Risk ratios (RRs) for categorical variables and standardized mean differences (SMDs) for continuous variables were calculated with 95% confidence intervals (CIs) using a random-effects model.

RESULTS

Twelve retrospective studies and one prospective study (Impella n=6652, ECMO n=1232) were identified. Impella use was associated with lower incidence of in-hospital mortality (RR 0.88 [95% CI 0.80-0.94], p=0.0004), stroke (RR 0.30 [0.21-0.42], p<0.00001), access-site bleeding (RR 0.50 [0.37-0.69], p<0.0001), major bleeding (RR 0.56 [0.39-0.80], p=0.002), and limb ischemia (RR 0.42 [0.27-0.65], p=0.0001). Baseline lactate levels were significantly lower in the Impella group (SMD -0.52 [-0.73- -0.31], p<0.00001). There was no significant difference in mortality at 6-12 months, MCS duration, need for MCS escalation, bridge-to-LVAD or heart transplant, and renal replacement therapy use between Impella and ECMO groups.

CONCLUSION

In patients with CS, Impella device use was associated with lower in-hospital mortality, stroke, and device-related complications than ECMO. However, patients in the ECMO group had higher baseline lactate levels.

Hemolysis during short-term mechanical circulatory support: from pathophysiology to diagnosis and treatment

INTRODUCTION

Despite advances in heart failure therapies and percutaneous coronary interventions, survival for cardiogenic shock remains poor. Percutaneous ventricular assist devices (pVAD) are increasingly used, but current evidence remains conflicting. The Impella is an example of such a device, based on a catheter mounted micro-axial continuous flow pump, that has been rapidly adopted in routine practice. An important aspect in the post implantation care is the prevention of complications. Hemolysis is one of the more frequent complications seen with this device.

AREAS COVERED

In this review we discuss the pathophysiology, diagnosis and treatment of hemolysis in patients supported with a pVAD. A practical algorithm for rapid identification of hemolysis and the underlying cause is presented, allowing for early treatment and prevention of further complications.

EXPERT OPINION

Hemolysis remains a threat to patients supported with any mechanical circulatory support device. Prevention as well as treatment demands for sufficient knowledge about the device, the optimal position and hemodynamics. Future studies should try to clarify some of the elements that are still unclear such as optimal anticoagulation, the place of pentoxyfilline or extracorporeal removal of free hemoglobin. This could help to optimize outcomes in clinical practice as well as future studies.

Impella versus Venoarterial Extracorporeal Membrane Oxygenation for Acute Myocardial Infarction Cardiogenic Shock: A Systematic Review and Meta-Analysis

Objectives: Despite an increase in the use of mechanical circulatory support (MCS) devices for acute myocardial infarction cardiogenic shock (AMI-CS), there is currently no randomised data directly comparing the use of Impella and veno-arterial extra-corporeal membrane oxygenation (VA-ECMO). Methods: Electronic databases of MEDLINE, EMBASE and CENTRAL were systematically searched in November 2021. Studies directly comparing the use of Impella (CP, 2.5 or 5.0) with VA-ECMO for AMI-CS were included. Studies examining other modalities of MCS, or other causes of cardiogenic shock, were excluded. The primary outcome was in-hospital mortality. Results: No randomised trials comparing VA-ECMO to Impella in patients with AMI-CS were identified. Six cohort studies (five retrospective and one prospective) were included for systematic review. All studies, including 7093 patients, were included in meta-analysis. Five studies reported in-hospital mortality, which, when pooled, was 42.4% in the Impella group versus 50.1% in the VA-ECMO group. Impella support for AMI-CS was associated with an 11% relative risk reduction in in-hospital mortality compared to VA-ECMO (risk ratio 0.89; 95% CI 0.83–0.96, I² 0%). Of the six studies, three studies also adjusted outcome measures via propensity-score matching with reported reductions in in-hospital mortality with Impella compared to VA-ECMO (risk ratio 0.72; 95% CI 0.59–0.86, I² 35%). Pooled analysis of five studies with 6- or 12-month mortality data reported a 14% risk reduction with Impella over the medium-to-long-term (risk ratio 0.86; 95% CI 0.76–0.97, I² 0%). Conclusions: There is no high-level evidence comparing VA-ECMO and Impella in AMI-CS. In available observation studies, MCS with Impella was associated with a reduced risk of in-hospital and medium-term mortality as compared to VA-ECMO.

When to Achieve Complete Revascularization in Infarct-Related Cardiogenic Shock

Acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) is a life-threatening condition frequently encountered in patients with multivessel coronary artery disease (CAD). Despite prompt revascularization, in particular, percutaneous coronary intervention (PCI), and therapeutic and technological advances, the mortality rate for patients with CS related to AMI remains unacceptably high. Differently form a hemodynamically stable setting, a culprit lesion-only (CLO) revascularization strategy is currently suggested for AMI–CS patients, based on the results of recent randomized evidence burdened by several limitations and conflicting results from non-randomized studies. Furthermore, mechanical circulatory support (MCS) devices have emerged as a key therapeutic option in CS, especially in the case of their early implantation without delaying revascularization and before irreversible organ damage has occurred. We provide an in-depth review of the current evidence on optimal revascularization strategies of multivessel CAD in infarct-related CS, assessing the role of different types of MCS devices and highlighting the importance of shock teams and medical care system networks to effectively impact on clinical outcomes.

Mechanical circulatory support in cardiogenic shock: a critical appraisal

INTRODUCTION

Acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) is a life-threatening condition frequently encounter in patients with multivessel coronary artery disease (MVD).

AREAS COVERED

Despite prompt revascularization, in particular percutaneous coronary intervention (PCI), and therapeutic and technological advances, the mortality rate for CS related to AMI remains high. Differently from hemodynamically stable setting, a culprit lesion-only (CLO) revascularization strategy is currently suggested in AMI-CS patients, based on the results of a recent randomized evidence burdened by several limitations and conflicting results from non-randomized studies. Furthermore, mechanical circulatory support (MCS) devices have raised as a key therapeutic option in CS, especially in case of an early implantation without delaying revascularization and before irreversible organ damage has occurred. We provide an in-depth review of current evidences on optimal revascularization strategies of multivessel CAD in infarct-related CS, assessing the role of MCS devices, and highlighting the importance of shock teams and medical care system networks to effectively impact on clinical outcomes.

EXPERT OPINION

Emerging observational experience suggested that an early implantation of MCS (prior to PCI), the performance of an extensive revascularization and the implementation of shock teams and networks are key factors for improving clinical outcomes.

Percutaneous Transvalvular Microaxial Flow Pump Support in Cardiology

The Impella device (Impella, Abiomed, Danvers, MA) is a percutaneous transvalvular microaxial flow pump that is currently used for (1) cardiogenic shock, (2) left ventricular unloading (combination of venoarterial extracorporeal membrane oxygenation and Impella concept), (3) high-risk percutaneous coronary interventions, (4) ablation of ventricular tachycardia, and (5) treatment of right ventricular failure. Impella-assisted forward blood flow increased mean arterial pressure and cardiac output, peripheral tissue perfusion, and coronary blood flow in observational studies and some randomized trials. However, because of the need for large-bore femoral access (14 F for the commonly used Impella CP device) and anticoagulation, the incidences of bleeding and ischemic complications are as much as 44% and 18%, respectively. Hemolysis is reported in as many as 32% of patients and stroke in as many as 13%. Despite the rapidly growing use of the Impella device, there are still insufficient data on its effect on outcome and complications on the basis of large, adequately powered randomized controlled trials. The only 2 small and also underpowered randomized controlled trials in cardiogenic shock comparing Impella versus intra-aortic balloon pump did not show improved mortality. Several larger randomized controlled trials are currently recruiting patients or are in preparation in cardiogenic shock (DanGer Shock [Danish-German Cardiogenic Shock Trial; NCT01633502]), left ventricular unloading (DTU-STEMI [Door-To-Unload in ST-Segment-Elevation Myocardial Infarction; NCT03947619], UNLOAD ECMO [Left Ventricular Unloading to Improve Outcome in Cardiogenic Shock Patients on VA-ECMO], and REVERSE [A Prospective Randomised Trial of Early LV Venting Using Impella CP for Recovery in Patients With Cardiogenic Shock Managed With VA ECMO; NCT03431467]) and high-risk percutaneous coronary intervention (PROTECT IV [Impella-Supported PCI in High-Risk Patients With Complex Coronary Artery Disease and Reduced Left Ventricular Function; NCT04763200]).

Rates and impact of vascular complications in mechanical circulatory support

BACKGROUND

Mechanical circulatory support (MCS) devices are increasingly used for hemodynamic support in cardiogenic shock or high-risk percutaneous coronary interventions. Vascular complications remain a major source of morbidity and mortality despite technological advances with percutaneous techniques. Little is known about the rates and predictors of vascular complications with large-bore access MCS in the contemporary era.

METHODS

The study cohort was derived from National Inpatient Sample using data from 2015 to 2019 for cardiac hospitalizations with the use of: intra-aortic balloon pump (IABP) Impella, and/or extracorporeal membrane oxygenation (ECMO). The rates of vascular complications and in-hospital outcomes were analyzed using multivariable logistic regression.

RESULTS

Of 221,700 hospitalizations with MCS use, the majority had only IABP (68%). The rates of vascular complications were greatest with ECMO (15.8%) when compared with IABP (3.0%) and Impella (5.6%). Among patients with vascular complications, in-hospital mortality was higher with ECMO (56.3%) when compared with IABP (26.2%) and Impella (33.8%). Peripheral arterial disease (PAD) was the strongest predictor of vascular complications, with 10 times higher odds when present (adjusted odds ratio [aOR] 10.96, p < 0.001). In risk-adjusted models, when compared with IABP, the use of Impella (aOR: 1.73, p < 0.001), ECMO (aOR: 5.35, p < 0.001), or a combination of MCS devices (aOR: 3.47, p < 0.001) was associated with higher odds of vascular complications.

CONCLUSIONS

In contemporary practice, the use of MCS is associated with significant vascular complications and in-hospital mortality. Predictors of vascular complications include larger arteriotomy size, female gender, and peripheral arterial disease. Vascular access management remains essential to prevent major complications.

A Comprehensive Review of Mechanical Circulatory Support Devices

Treatment strategies to combat cardiogenic shock (CS) have remained stagnant over the past decade. Mortality rates among patients who suffer CS after acute myocardial infarction (AMI) remain high at 50%. Mechanical circulatory support (MCS) devices have evolved as novel treatment strategies to restore systemic perfusion to allow cardiac recovery in the short term, or as durable support devices in refractory heart failure in the long term. Haemodynamic parameters derived from right heart catheterization assist in the selection of an appropriate MCS device and escalation of mechanical support where needed. Evidence favouring the use of one MCS device over another is scant. An intra-aortic balloon pump is the most commonly used short-term MCS device, despite providing only modest haemodynamic support. Impella CP® has been increasingly used for CS in recent times and remains an important focus of research for patients with AMI-CS. Among durable devices, Heartmate® 3 is the most widely used in the USA. Adequately powered randomized controlled trials are needed to compare these MCS devices and to guide the operator for their use in CS. This article provides a brief overview of the types of currently available MCS devices and the indications for their use.

Budget Impact Analysis of Impella CP® Utilization in the Management of Cardiogenic Shock in France: A Health Economic Analysis

Introduction

Early detection and treatment of cardiogenic shock (CS) is crucial to avoid irreparable multiorgan damage and mortality. Impella CP^® is a novel temporary mechanical circulatory support (MCS) device associated with greater hemodynamic support and significantly fewer device-related complications compared with other MCS devices, e.g., intra-aortic balloon pumps (IABP) and venoarterial extracorporeal membrane oxygenation (VA-ECMO). The present study evaluated the budget impact of introducing Impella CP versus IABP and VA-ECMO in patients with CS following an acute myocardial infarction (MI) in France.

Methods

A budget impact model was developed to compare the cost of introducing Impella CP with continuing IABP and VA-ECMO treatment from a Mandatory Health Insurance (MHI) perspective in France over a 5-year time horizon, with 700 patients with refractory CS assumed to be eligible for treatment per year. Costs associated with Impella CP and device-related complications for all interventions were captured and clinical input data were based on published sources. Scenario analyses were performed around key parameters.

Results

Introducing Impella CP was associated with cumulative cost savings of EUR 2.7 million over 5 years, versus continuing current clinical practice with IABP and VA-ECMO. Cost savings were achieved in every year of the analysis and driven by the lower incidence of device-related complications with Impella CP, with estimated 5-year cost savings of EUR 22.4 million due to avoidance of complications. Total cost savings of more than EUR 250,000 were projected in the first year of the analysis, which increased as the market share of Impella CP was increased. Scenario analyses indicated that the findings of the analysis were robust.

Conclusion

Treatment with Impella CP in adult patients aged less than 75 years in a state of refractory CS following an MI was projected to lead to substantial cost savings from an MHI perspective in France, compared with continuing current clinical practice.

Mortality in cardiogenic shock patients receiving mechanical circulatory support: a network meta-analysis

Objective

Mechanical circulatory support (MCS) devices are widely used for cardiogenic shock (CS). This network meta-analysis aims to evaluate which MCS strategy offers advantages.

Methods

A systemic search of PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials was performed. Studies included double-blind, randomized controlled, and observational trials, with 30-day follow-ups. Paired independent researchers conducted the screening, data extraction, quality assessment, and consistency and heterogeneity assessment.

Results

We included 39 studies (1 report). No significant difference in 30-day mortality was noted between venoarterial extracorporeal membrane oxygenation (VA-ECMO) and VA-ECMO plus Impella, Impella, and medical therapy. According to the surface under the cumulative ranking curve, the optimal ranking of the interventions was surgical venting plus VA-ECMO, medical therapy, VA-ECMO plus Impella, intra-aortic balloon pump (IABP), Impella, Tandem Heart, VA-ECMO, and Impella plus IABP. Regarding in-hospital mortality and 30-day mortality, the forest plot showed low heterogeneity. The results of the node-splitting approach showed that direct and indirect comparisons had a relatively high consistency.

Conclusions

IABP more effectively reduce the incidence of 30-day mortality compared with VA-ECMO and Impella for the treatment of CS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02493-0.

Cardiogenic Shock Management and Research: Past, Present, and Future Outlook

Although great strides have been made in the pathophysiological understanding, diagnosis and management of cardiogenic shock (CS), morbidity and mortality in patients presenting with the condition remain high. Acute MI is the commonest cause of CS; consequently, most existing literature concerns MI-associated CS. However, there are many more phenotypes of patients with acute heart failure. Medical treatment and mechanical circulatory support are well-established therapeutic options, but evidence for many current treatment regimens is limited. The issue is further complicated by the fact that implementing adequately powered, randomized controlled trials are challenging for many reasons. In this review, the authors discuss the history, landmark trials, current topics of medical therapy and mechanical circulatory support regimens, and future perspectives of CS management.

Cardiac Surgery in Advanced Heart Failure

Mechanical circulatory support and heart transplantation are established surgical options for treatment of advanced heart failure. Since the prevalence of advanced heart failure is progressively increasing, there is a clear need to treat more patients with mechanical circulatory support and to increase the number of heart transplantations. This narrative review summarizes recent progress in surgical treatment options of advanced heart failure and proposes an algorithm for treatment of the advanced heart failure patient at >65 years of age.

Impella mechanical circulatory support for Takotsubo syndrome with shock: A retrospective multicenter analysis

OBJECTIVES

To analyze the characteristics and outcome of Impella mechanical circulatory support (MCS) for Takotsubo syndrome (TS) with cardiogenic shock.

BACKGROUND

TS is an acute heart failure syndrome characterized by transient severe reduction of left ventricular (LV) systolic function, with cardiogenic shock occurring in around 10% of patients. Since inotropes should be avoided due to their role in TS pathogenesis and aggravation of LV outflow tract obstruction, the use of MCS as treatment is a viable treatment option, however, studies are lacking.

METHODS

The catheter-based ventricular assist device (cVAD) registry and local MCS databases were screened for TS patients with cardiogenic shock (TS-CS) supported with an Impella percutaneous ventricular assist device (pVAD). Patient and treatment characteristics and in-hospital outcomes were retrospectively analyzed.

RESULTS

At 10 US and European centers, 16 TS-CS patients supported with an Impella pVAD were identified between December 2013 and May 2018 (mean age, 61.8 ± 15.5 years; 87.5% women). LV ejection fraction (LVEF) at presentation was severely reduced (mean, 19.4 ± 8.3%). Prior to MCS, 13 patients (81.3%) were mechanically ventilated, 4 patients (25.0%) had been resuscitated, and mean serum lactate was 4.7 ± 3.5 mmol/L. Mean duration of Impella support was 1.9 ± 1.0 days (range, 1-4 days). Thirteen patients (81.3%) survived to discharge, and all survivors experienced cardiac recovery with significant improvement of LVEF at discharge compared to baseline (20.4 ± 8.8 vs. 52.9 ± 12.0, P < 0.001).

CONCLUSIONS

This is the first series of TS-CS patients supported with an Impella pVAD. Mortality was low, and LV systolic function recovered in all survivors. Prospective studies of Impella support in this special condition are warranted.

Current Landscape of Temporary Percutaneous Mechanical Circulatory Support Technology

Mechanical circulatory support devices provide hemodynamic support to patients who present with cardiogenic shock. These devices work using different mechanisms to provide univentricular or biventricular support. There is a growing body of evidence supporting use of these devices as a goal for cardiac recovery or as a bridge to definitive therapy, but definitive, well-powered studies are still needed. Mechanical circulatory support devices are increasingly used using shock team and protocols, which can help clinicians in decision making, balancing operator and institutional experience and expertise. The aim of this article is to review commercially available mechanical circulatory support devices, their profiles and mechanisms of action, and the evidence available regarding their use.

Comparison of Mechanical Support with Impella or Extracorporeal Life Support in Post-Cardiac Arrest Cardiogenic Shock: A Propensity Scoring Matching Analysis

Our aim was to compare the outcomes of Impella with extracorporeal life support (ECLS) in patients with post-cardiac arrest cardiogenic shock (CS) complicating acute myocardial infarction (AMI). This was a retrospective study of patients resuscitated from out of hospital cardiac arrest (OHCA) with post-cardiac arrest CS following AMI (May 2015 to May 2020). Patients were supported either with Impella 2.5/CP or ECLS. Outcomes were compared using propensity score-matched analysis to account for differences in baseline characteristics between groups. 159 patients were included (Impella, n = 105; ECLS, n = 54). Hospital and 12-month survival rates were comparable in the Impella and the ECLS groups (p = 0.16 and p = 0.3, respectively). After adjustment for baseline differences, both groups demonstrated comparable hospital and 12-month survival (p = 0.36 and p = 0.64, respectively). Impella patients had a significantly greater left ventricle ejection-fraction (LVEF) improvement at 96 h (p < 0.01 vs. p = 0.44 in ECLS) and significantly fewer device-associated complications than ECLS patients (15.2% versus 35.2%, p < 0.01 for relevant access site bleeding, 7.6% versus 20.4%, p = 0.04 for limb ischemia needing intervention). In subgroup analyses, Impella was associated with better survival in patients with lower-risk features (lactate < 8.6 mmol/L, time from collapse to return of spontaneous circulation < 28 min, vasoactive score < 46 and Horowitz index > 182). In conclusion, the use of Impella 2.5/CP or ECLS in post-cardiac arrest CS after AMI was associated with comparable adjusted hospital and 12-month survival. Impella patients had a greater LVEF improvement than ECLS patients. Device-related access-site complications occurred more frequently in patients with ECLS than Impella support.

Temporary mechanical circulatory support devices: updates from recent studies

PURPOSE OF REVIEW

Over the past several years, the role of short-term mechanical circulatory support (MCS) devices has become the dominant focus in efforts to improve outcomes in patients with cardiogenic shock (CS). Alongside these efforts, temporary MCS devices have been increasingly used to support patients prior to cardiac surgery, during high-risk percutaneous coronary intervention, awaiting cardiac transplantation, and in the setting of refractory cardiac arrest. The present review aims to provide an update on the recent literature evaluating the evolving role of temporary MCS devices, and to provide insights into the current challenges and future directions of MCS research.

RECENT FINDINGS

Recent observational data have demonstrated potential roles for intra-aortic balloon pump preoperatively in high-risk patients awaiting coronary artery bypass grafting, and advanced heart failure patients awaiting transplantation. Impella continues to demonstrate promising results as part of an early MCS strategy in CS, as a temporary bridge to transplantation, and as a mechanism for left ventricular unloading in patients on venoarterial extracorporeal membrane oxygenation (ECMO). Finally, the first randomized trial of ECMO facilitated resuscitation in the United States demonstrated improved survival in patients with refractory out of hospital cardiac arrest.

SUMMARY

Though randomized data remains limited, observational data continue to support the role of temporary MCS devices in a variety of clinical settings.

Recent insights into pathophysiology and management of mechanical complications of myocardial infarction

PURPOSE OF REVIEW

Mechanical complications of myocardial infarction are a group of postischemic events and include papillary muscle rupture resulting in ischemic mitral regurgitation, ventricular septal defect, left ventricle free wall rupture, pseudoaneurysm, and true aneurysm. Advances made in management strategies, such as the institution of 'Code STEMI' and percutaneous interventions, have lowered the incidence of these complications. However, their presentation is still associated with increased morbidity and mortality. Early diagnosis and appropriate management is crucial for facilitating better clinical outcomes.

RECENT FINDINGS

Although the exact timing of a curative intervention is not known, emerging percutaneous and transcatheter approaches and improving mechanical circulatory support (MCS) devices have greatly enhanced our ability to manage and treat some of the complications postinfarct.

SUMMARY

Although the incidence of mechanical complications of myocardial infarction has decreased over the past few decades, these complications are still associated with high rates of morbidity and mortality. The combination of early and accurate diagnosis and subsequent appropriate management are imperative for optimizing clinical outcomes. Although more randomized clinical trials are needed, mechanical circulatory support devices and emerging therapeutic strategies can be offered to carefully selected patients.

Currently Available Options for Mechanical Circulatory Support for the Management of Cardiogenic Shock

Cardiogenic shock (CS) is a complex condition with a high risk for morbidity and mortality. Mechanical circulatory support (MCS) devices were developed to support patients with CS in cases refractory to treatment with vasoactive medications. Current devices include intra-aortic balloon pumps, intravascular microaxial pumps, percutaneous LVAD, percutaneous RVAD, and VA ECMO. Data from limited observational studies and clinical trials show a clear difference in the level of hemodynamic support offered by each device. However, at this point, there are insufficient clinical trial data to guide MCS selection and, until ongoing clinical trials are completed, use of the right device for the right patient depends largely on clinical judgment.