Device profile of the Impella 5.0 and 5.5 system for mechanical circulatory support for patients with cardiogenic shock: overview of its safety and efficacy

Clinical outcomes among cardiogenic shock patients supported with high-capacity Impella axial flow pumps: A report from the Cardiogenic Shock Working Group

BACKGROUND

The Impella 5.0 and 5.5 pumps (Abiomed, Danvers, MA) are large-bore transvalvular micro-axial assist devices used in cardiogenic shock (CS) for patients requiring high-capacity flow. Despite their increasing use, real-world data regarding indications, rates of utilization and clinical outcomes with this therapy are limited. The objective of our study was to examine clinical profiles and outcomes of patients in a contemporary, real-world CS registry of patients who received an Impella 5.0/5.5 alone or in combination with other temporary mechanical circulatory support (tMCS) devices.

METHODS

The CS Working Group (CSWG) Registry includes patients from 34 US hospitals. For this analysis, data from patients who received an Impella 5.0/5.5 between 2020-2023 were analyzed. Use of Impella 5.0/5.5 with or without additional tMCS therapies, duration of support, adverse events and outcomes at hospital discharge were studied. Adverse events including stroke, limb ischemia, bleeding and hemolysis were not standardized by the registry but reported per individual CSWG Primary Investigator discretion. For those who survived, rates of native heart recovery (NHR) or heart replacement therapy (HRT) including heart transplant (HT), or durable ventricular assist device (VAD) were recorded. We also assessed outcomes based on shock etiology (acute myocardial infarction or MI-CS vs. heart failure-related CS or HF-CS).

RESULTS

Among 6,205 patients, 754 received an Impella 5.0/5.5 (12.1%), including 210 MI-CS (27.8%) and 484 HF-CS (64.1%) patients. Impella 5.0/5.5 was used as the sole tMCS device in 32% of patients, while 68% of patients received a combination of tMCS devices. Impella cannulation sites were available for 524/754 (69.4%) of patients, with 93.5% axillary configuration. Survival to hospital discharge for those supported with an Impella 5.0/5.5 was 67%, with 20.4% NHR and 45.5% HRT. Compared to HF-CS, patients with MI-CS supported on Impella 5.0/5.5 had higher in-hospital mortality (45.2% vs 26.2%, p < 0.001) and were less likely to receive HRT (22.4% vs 56.6%, p < 0.001. For patients receiving a combination of tMCS during hospitalization, this was associated with higher rates of limb ischemia (9% vs. 3%, p < 0.01), bleeding (52% vs 33%, p < 0.01), and mortality (38% vs 25%; p < 0.001) compared to Impella 5.0/5.5 alone. Among Impella 5.0/5.5 recipients, the median duration of pump support was 12.9 days (IQR: 6.8-22.9) and longer in patients bridged to HRT (14 days; IQR: 7.7-28.4).

CONCLUSIONS

In this multi-center cohort of patients with CS, use of Impella 5.0/5.5 was associated with an overall survival of 67.1% and high rates of HRT. Lower adverse event rates were observed when Impella 5.0/5.5 was the sole support device used. Further study is required to determine whether a strategy of early Impella 5.0/5.5 use for CS improves survival.

CONDENSED ABSTRACT

High capacity Impella heart pumps are capable of provide up to 5.5 liter/min of flow while upper body surgical placement allows for ambulation. Patients with advanced cardiogenic shock from acute myocardial infarction or heart failure requiring temporary mechanical circulatory support may benefit from upfront use of Impella 5.5 to improve overall survival, including native heart recovery or successful bridge to durable left ventricular assist device surgery or heart transplantation.

Extended Duration of Impella 5.5 Support Does Not Adversely Impact Outcomes Following Heart Transplantation: A National Registry Analysis

Prior studies assessing the effects of Impella 5.5 support duration on posttransplant outcomes have been limited to single-center case reports and series. This study evaluates the impact of Impella 5.5 support duration on outcomes following heart transplantation using the United Network for Organ Sharing database. Adult heart transplant recipients who were directly bridged to primary isolated heart transplantation with Impella 5.5 were included. The cohort was stratified into two groups based on the duration of Impella support: less than or equal to 14 and greater than 14 days. The primary outcome was 90 day posttransplant survival. Propensity score matching was performed. Sub-analysis was conducted to evaluate the impact of greater than 30 days of Impella support on 90 day survival. Three hundred thirty-two recipients were analyzed. Of these, 212 recipients (63.9%) were directly bridged to heart transplantation with an Impella support duration of greater than 14 days. The two groups had comparable 90 day posttransplant survival and complication rates. The comparable posttransplant survival persisted in a propensity score-matched comparison. In the sub-analysis, Impella support duration of greater than or equal to 30 days did not adversely impact 90 day survival. This study demonstrates that extended duration of support with Impella 5.5 as a bridge to transplantation does not adversely impact posttransplant outcomes. Impella 5.5 is a safe and effective bridging modality to heart transplantation.

Prolonged Impella 5.0/5.5 support within different pathways of care for cardiogenic shock: the experience of a referral center

Aims

Impella 5.0 and 5.5 are promising low-invasive left ventricle (LV) temporary mechanical circulatory supports (tMCS) for cardiogenic shock due to LV mechanical unloading and are paired with powerful hemodynamic support. This study aimed to analyze data and destinies of patients supported with Impella 5.0/5.5 at a national referral center for cardiogenic shock and to assess the parameters associated with myocardial recovery and successful weaning.

Methods

A single-center observational study was conducted on all patients treated with Impella 5.0 or 5.5 from March 2018 to July 2023.

Results

A total of 59 patients underwent Impella 5.0/5.5 implantation due to profound cardiogenic shock, with acute myocardial infarction being the most frequent cause of shock (42 patients, 71%). The median duration of Impella support was 13 days (maximum duration of 52 days). Axillary cannulation was feasible in almost all patients, and 36% were mobilized during support. A total of 44 patients (75%) survived to the next therapy/recovery: 21 patients experienced recovery and 15 and 8 were bridged to long-term LVAD and heart transplantation, respectively. The global survival rate was 66%. The predictors of native heart recovery at multivariate analysis were the number of days on tMCS before upgrade to Impella 5.0/5.5 [hazard ratio (HR) 0.68 (0.51-9) p = 0.0068] and improvement of LVEF within the first 7-10 days of support [HR 4.72 (1.34-16.7), p = 0.016].

Conclusions

Transcatheter systems such as Impella 5.0/5.5 revolutionized the field of tMCS. Myocardial recovery is the primary clinical target. Its prognostication and promotion are key to ensure the most proficuous course for each patient from cardiogenic shock to long-term event-free survival.

Impella versus VA-ECMO for the treatment of patients with cardiogenic shock: the Impella Network Project - observational study protocol for cost-effectiveness and budget impact analyses

INTRODUCTION

The treatment of patients with cardiogenic shock (CS) encompasses several health technologies including Impella pumps and venoarterial extracorporeal membrane oxygenation (VA-ECMO). However, while they are widely used in clinical practice, information on resource use and quality of life (QoL) associated with these devices is scarce. The aim of this study is, therefore, to collect and comparatively assess clinical and socioeconomic data of Impella versus VA-ECMO for the treatment of patients with severe CS, to ultimately conduct both a cost-effectiveness (CEA) and budget impact (BIA) analyses.

METHODS AND ANALYSIS

This is a prospective plus retrospective, multicentre study conducted under the scientific coordination of the Center for Research on Health and Social Care Management of SDA Bocconi School of Management and clinical coordination of Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute in Milan. The Impella Network stemmed for the purposes of this study and comprises 17 Italian clinical centres from Northern to Southern Regions in Italy. The Italian network qualifies as a subgroup of the international Impella Cardiac Surgery Registry. Patients with CS treated with Impella pumps (CP, 5.0 or 5.5) will be prospectively recruited, and information on clinical outcomes, resource use and QoL collected. Economic data will be retrospectively matched with data from comparable patients treated with VA-ECMO. Both CEA and BIA will be conducted adopting the societal perspective in Italy. This study will contribute to generate new socioeconomic evidence to inform future coverage decisions.

ETHICS AND DISSEMINATION

As of May 2024, most of the clinical centres submitted the documentation to their ethical committee (N=13; 76%), six centres received ethical approval and two centres started to enrol patients. Study results will be published in peer-reviewed publications and disseminated through conference presentations.

Predictors of long-term success after successful explantation of continuous flow left ventricular assist device support

OBJECTIVES

Predictors and evaluations of continuous flow left ventricular assist device (cf-LVAD) explantation in recovered patients remain under discussion due to lack of evidence on long-term safety and efficacy. This study summarized our experiences regarding cf-LVAD explantation in non-ischaemic dilated cardiomyopathy patients and estimated a predictor for sufficient myocardial recovery allowing left ventricular assist device explant.

METHODS

We retrospectively identified 135 adult patients with cf-LVAD therapy as bridge to heart transplant due to non-ischaemic dilated cardiomyopathy. Of those, 13 patients underwent device explantation (recovery group) after myocardial recovery. Twelve (92%) of the explanted patients were evaluated using our weaning protocol and underwent surgical explantation. Meanwhile, the remaining 122 continued with cf-LVAD therapy (non-recovery group).

RESULTS

Multivariate logistic regression analysis revealed time interval between the first heart failure event and cf-LVAD implantation as an independent predictor for successful explantation. The optimal time interval cutoff value to predict cf-LVAD explantation was 7 months, with a sensitivity of 91.0% and specificity of 84.6%. Echocardiography in patients with successful cf-LVAD explantation showed significant improvement of left ventricular function and dimensions at 6 months postoperatively. The 13 explanted patients are currently alive at a median of 30 (interquartile range; 18-58) months after explantation. The survival rate free from rehospitalization due to heart failure following explantation was 100%. Left ventricular function and remodelling after explantation were also preserved.

CONCLUSIONS

In non-ischaemic dilated cardiomyopathy patients with a short interval between the first heart failure event and cf-LVAD therapy, left ventricular myocardium may recover in an early phase after device implantation.

Left ventricular unloading via percutaneous assist device during extracorporeal membrane oxygenation in acute myocardial infarction and cardiac arrest

INTRODUCTION

A feared complication of an acute myocardial infarction (AMI) is cardiac arrest (CA). Even if return of spontaneous circulation is achieved, cardiogenic shock (CS) is common. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) supports patients with CS and is often used in conjunction with an Impella device (2.5 and CP) to off-load the left ventricle, although limited evidence supports this approach.

METHODS

The goal of this study was to determine whether a mortality difference was observed in VA-ECMO alone versus VA-ECMO with Impella (ECPELLA) in patients with CS from AMI and CA. A retrospective chart review of 50 patients with AMI-CS and CA and were supported with VA-ECMO (n = 34) or ECPELLA (n = 16) was performed. The primary outcome was all-cause mortality at 6-months from VA-ECMO or Impella implantation. Secondary outcomes included in-hospital mortality and complication rates between both cohorts and intensive care unit data.

RESULTS

Baseline characteristics were similar, except patients with ST-elevation myocardial infarction were more likely to be in the VA-ECMO group (p = 0.044). The ECPELLA cohort had significantly worse survival after VA-ECMO (SAVE) score (p = 0.032). Six-month all-cause mortality was not significantly different between the cohorts, even when adjusting for SAVE score. Secondary outcomes were notable for an increased rate of minor complications without an increased rate of major complications in the ECPELLA group.

CONCLUSIONS

Randomized trials are needed to determine if a mortality difference exists between VA-ECMO and ECPELLA platforms in patients with AMI complicated by CA and CS.

Percutaneous Mechanical Circulatory Support in Acute Heart Failure Complicated with Cardiogenic Shock

Despite advancements in algorithms concerning the management of cardiogenic shock, current guidelines still lack the adequate integration of mechanical circulatory support devices. In recent years, more and more devices have been developed to provide circulatory with or without respiratory support, when conservative treatment with inotropic agents and vasopressors has failed. Mechanical circulatory support can be contemplated for patients with severe, refractory, or acute-coronary-syndrome-related cardiogenic shock. Through this narrative review, we delve into the differences among the types of currently used devices by presenting their notable advantages and inconveniences. We address the technical issues emerging while choosing the best possible device, temporarily as a bridge to another treatment plan or as a destination therapy, in the optimal timing for each type of patient. We also highlight the diverse implantation and removal techniques to avoid major complications such as bleeding and limb ischemia. Ultimately, we hope to shed some light in the gaps of evidence and the importance of conducting further organized studies around the topic of mechanical circulatory support when dealing with such a high mortality rate.

Cardiac Devices and Kidney Disease

A growing variety of cardiac devices are available to monitor or support cardiovascular function. The entwined nature of cardiovascular disease and kidney disease makes the relationship of these devices with kidney disease a multifaceted question relating to the use of these devices in individuals with kidney disease and to the effects of the devices and device placement on kidney health. Cardiac devices can be categorized broadly into cardiac implantable electronic devices, structural devices, and circulatory assist devices. Cardiac implantable electronic devices include devices for monitoring and managing cardiac electrical activity and devices for monitoring hemodynamics. Structural devices modify cardiac structure and include valve prostheses, valve repair clips, devices for treating atrial septal abnormalities, left atrial appendage closure devices, and interatrial shunt devices. Circulatory assist devices support the failing heart or support cardiac function during high-risk cardiac procedures. Evidence for the use of these devices in individuals with kidney disease, effects of the devices on kidney health and function, specific considerations with devices in kidney disease, and important knowledge gaps are surveyed in this article. With the growing prevalence of combined cardiorenal disease and the increasing variety of cardiac devices, kidney disease considerations are an important aspect of device therapy.

The Year in Cardiothoracic and Vascular Anesthesia: Selected Highlights From 2023

This special article is the 16th in an annual series for the Journal of Cardiothoracic and Vascular Anesthesia. The authors thank the editor-in-chief, Dr. Kaplan, and the editorial board for the opportunity to continue this series, namely the research highlights of the past year in the specialty of cardiothoracic and vascular anesthesiology. The major themes selected for 2023 are outlined in this introduction, and each highlight is reviewed in detail in the main article. The literature highlights in the specialty for 2023 begin with an update on perioperative rehabilitation in cardiothoracic surgery, with a focus on novel methods to best assess patients in the preoperative and postoperative periods, and the impact of rehabilitation on outcomes. The second major theme is focused on cardiac surgery, with the authors discussing new insights into inhaled pulmonary vasodilators, coronary revascularization surgery, and discussion of causes of coronary graft failure after surgery. The third theme is focused on cardiothoracic transplantation, with discussions focusing on bridge-to-transplantation strategies. The fourth theme is focused on mechanical circulatory support, with discussions focusing on both temporary and durable support. The fifth and final theme is an update on medical cardiology, with a focus on outcomes of invasive approaches to heart disease. The themes selected for this article are only a few of the diverse advances in the specialty during 2023. These highlights will inform the reader of key updates on various topics, leading to improved perioperative outcomes for patients with cardiothoracic and vascular disease.

Cardiogenic shock etiology and exit strategy impact survival in patients with Impella 5.5

BACKGROUND

Despite historical differences in cardiogenic shock (CS) outcomes by etiology, outcomes by CS etiology have yet to be described in patients supported by temporary mechanical circulatory support (MCS) with Impella 5.5.

OBJECTIVES

This study aims to identify differences in survival and post-support destination for these patients in acute myocardial infarction (AMI) and acute decompensated heart failure (ADHF) CS at a high-volume, tertiary, transplant center.

METHODS

A retrospective review of patients who received Impella 5.5 at our center from November 2020 to June 2022 was conducted.

RESULTS

Sixty-seven patients underwent Impella 5.5 implantation for CS; 23 (34%) for AMI and 44 (66%) for ADHF. AMI patients presented with higher SCAI stage, pre-implant lactate, and rate of prior MCS devices, and fewer days from admission to implantation. Survival was lower for AMI patients at 30 days, 90 days, and discharge. No difference in time to all-cause mortality was found when excluding patients receiving transplant. There was no significant difference in complication rates between groups.

CONCLUSIONS

ADHF-CS patients with Impella 5.5 support have a significantly higher rate of survival than patients with AMI-CS. ADHF patients were successfully bridged to heart transplant more often than AMI patients, contributing to increased survival.

Reconsidering FDA Guidelines: A Single-Center Experience of Prolonged Impella 5.5 Support

OBJECTIVE

Impella 5.5 (Abiomed, Danvers, MA, USA) is approved by the US Food and Drug Administration (FDA) for mechanical circulatory support for ≤14 days. It is unknown whether prolonged support is associated with worse outcomes. We sought to review our single-center experience with Impella 5.5 and compare outcomes based on support duration.

METHODS

We retrospectively reviewed adult patients (≥18 years old) supported with Impella 5.5 at our institution (May 2020 to April 2023). Patients on prolonged support (>14 days) were compared with those supported for ≤14 days.

RESULTS

There were 31 patients supported with Impella 5.5 including 14 (45.2%) supported >14 days. Median support duration for those on prolonged support was 43.5 (interquartile range [IQR] 25 to 63.5) days versus 8 (IQR 6, 13) days for those who were not (P < 0.001). Overall, the device-related complication rate was 9.7% and did not differ between groups (P = 0.08). Overall, 30-day postimplant survival was 71% and did not differ by support duration (P = 0.2). In-hospital mortality was 32% and did not differ between cohorts (P > 0.99). Among those surviving to explant (n = 22), long-term strategy included bridge to durable ventricular assist device (18%, n = 4), cardiac transplant (55%, n = 12), and cardiac recovery (27%, n = 6).

CONCLUSIONS

High-risk patients with cardiogenic shock may be supported with Impella 5.5 beyond the FDA-approved duration without increased risk of complications or mortality.

Utilization of the percutaneous left ventricular support as bridge to heart transplantation across the United States: In-depth UNOS database analysis

BACKGROUND

Intra-aortic balloon pump (IABP) and Impella device utilization as a bridge to heart transplantation (HTx) have risen exponentially. We aimed to explore the influence of device selection on HTx outcomes, considering regional practice variation.

METHODS

A retrospective longitudinal study was performed on a United Network for Organ Sharing (UNOS) registry dataset. We included adult patients listed for HTx between October 2018 and April 2022 as status 2, as justified by requiring IABP or Impella support. The primary end-point was successful bridging to HTx as status 2.

RESULTS

Of 32,806 HTx during the study period, 4178 met inclusion criteria (Impella n = 650, IABP n = 3528). Waitlist mortality increased from a nadir of 16 (in 2019) to a peak of 36 (in 2022) per thousand status 2 listed patients. Impella annual use increased from 8% in 2019 to 19% in 2021. Compared to IABP, Impella patients demonstrated higher medical acuity and lower success rate of transplantation as status 2 (92.1% vs 88.9%, p < 0.001). The IABP:Impella utilization ratio varied widely between regions, ranging from 1.77 to 21.31, with high Impella use in Southern and Western states. However, this difference was not justified by medical acuity, regional transplant volume, or waitlist time and did not correlate with waitlist mortality.

CONCLUSIONS

The shift in utilizing Impella as opposed to IABP did not improve waitlist outcomes. Our results suggest that clinical practice patterns beyond mere device selection determine successful bridging to HTx. There is a critical need for objective evidence to guide tMCS utilization and a paradigm shift in the UNOS allocation system to achieve equitable HTx practice across the United States.

Impella 5.5 as a bridge to heart transplantation: Waitlist outcomes in the United States

OBJECTIVES

The 2018 United Network for Organ Sharing allocation policy change has led to a significant increase in the use of mechanical circulatory support devices in patients listed for orthotopic heart transplantation. However, there has been a paucity of data regarding the newest generation Impella 5.5, which received FDA approval in 2019.

METHODS

The United Network for Organ Sharing registry was queried for all adults awaiting orthotopic heart transplantation who received Impella 5.5 support during their listing period. Waitlist, device, and early post-transplant outcomes were assessed.

RESULTS

A total of 464 patients received Impella 5.5 support during their listing period with a median waitlist time of 19 days. Among them, 402 (87%) patients were ultimately transplanted, with 378 (81%) being directly bridged to transplant with the device. Waitlist death (7%) and clinical deterioration (5%) were the most common reasons for waitlist removal. Device complications and failure were uncommon (<5%). The most common post-transplant complication was acute kidney injury requiring dialysis (16%). Survival at 1-year post-transplant survival was 89.5%.

CONCLUSION

Since its approval, the Impella 5.5 has been increasingly used as a bridge to transplant. This analysis demonstrates robust waitlist and post-transplant outcomes with minimal device-related and postoperative complications.

Modification of a Transvalvular Microaxial Flow Pump for Instantaneous Determination of Native Cardiac Output and Volume

BACKGROUND

The current Impella cardiopulmonary (CP) pump, used for mechanical circulatory support in patients with cardiogenic shock (CS), cannot assess native cardiac output (CO) and left ventricular (LV) volumes. These data are valuable in facilitating device management and weaning. Admittance technology allows for accurate assessment of cardiac chamber volumes.

OBJECTIVES

This study tested the ability to engineer admittance electrodes onto an existing Impella CP pump to assess total and native CO as well as LV chamber volumes in an instantaneous manner.

METHODS

Impella CP pumps were fitted with 4 admittance electrodes and were placed in the LVs of adult swine (n = 9) that were subjected to 3 different hemodynamic conditions, including Impella CP speed adjustments, administration of escalating doses of dobutamine and microsphere injections into the left main artery to result in cardiac injury. CO, according to admittance electrodes, was calculated from LV volumes and heart rate. In addition, CO was calculated in each instance via thermodilution, continuous CO measurement, the Fick principle, and aortic velocity-time integral by means of echocardiography.

RESULTS

Modified Impella CP pumps were placed in swine LVs successfully. CO, as determined by admittance electrodes, was similar by trend to other methods of CO assessment. It was corrected for pump speed to calculate native CO, and calculated LV chamber volumes trended as expected in each experimental protocol.

CONCLUSIONS

We report, for the first time, that an Impella CP pump can be fitted with admittance electrodes and used to determine total and native CO in various hemodynamic situations.

CONDENSED ABSTRACT

Transvalvular mechanical circulatory support devices such as the Impella CP do not have the ability to provide real-time information on native cardiac output (CO) and left ventricular (LV) volumes. This information is critical in device management and in weaning in patients with cardiogenic shock. We demonstrate, for the first time, that Impella CP pumps coupled with admittance electrodes are able to determine native CO and LV chamber volumes in multiple hemodynamic situations such as Impella pump speed adjustments, escalating dobutamine administration and cardiac injury from microsphere injection.

Temporary circulatory support with surgically implanted microaxial pumps in postcardiotomy cardiogenic shock following coronary artery bypass surgery

Objectives

Patients with ischemic cardiomyopathy undergoing coronary artery bypass grafting (CABG) surgery may develop postcardiotomy cardiogenic shock. In these cases, implantation of an Impella 5.0 or 5.5 microaxial pump offers full hemodynamic support while simultaneously unloading of the left ventricle.

Methods

Preoperative, perioperative, and postoperative data of all patients receiving postoperative support with an Impella 5.0 or 5.5 after CABG surgery between September 2017 and October 2022 were retrospectively collected. Cohort built-up was performed according to the timing of Impella implantation, either simultaneous during CABG surgery or delayed.

Results

A total of n = 42 patients received postoperative Impella support, of whom 27 patients underwent simultaneous Impella implantation during CABG surgery and 15 patients underwent delayed Impella therapy. Preoperative left ventricular ejection fraction was similarly low in both groups (26.7 ± 0.7% vs 24.8 ± 11.3%; P = .32). In the delayed cohort, Impella implantation was performed after a median of 1 (1; 2) days after CABG surgery. Survival after 30 days (75.6% vs 47.6%, P = .04) and 1 year (69.4% vs 29.8%, P = .03) was better in the cohort receiving simultaneous Impella implantation.

Conclusions

The combined advantages of hemodynamic support and LV unloading with microaxial pumps may lead to a favorable survival in patients with left ventricular failure following CABG surgery. Early implantation during the initial surgery shows a trend toward a more favorable survival as compared with patients receiving delayed support.

Evolution of concomitant use of veno-arterial extracorporeal membrane oxygenation support with Impella in cardiogenic shock: From percutaneous femoral Impella to axillary Impella 5.5

BACKGROUND

Little is known about safety and efficacy of the use of Impella 5.5 compared to previous iterations in the setting of Impella with Veno-Arterial Extracorporeal Membrane Oxygenation Support as ECPELLA.

METHODS

Consecutive patients who were treated by ECPELLA with surgically implanted axillary Impella 5.5 (N = 13) were compared with patients supported by ECPELLA with percutaneous femoral Impella CP or 2.5 (Control, N = 13).

RESULTS

The total ECPELLA flow was higher in ECPELLA 5.5 group (6.9 vs. 5.4 L/min, p = 0.019). Actual hospital survival was higher than predicted and comparable in both groups (ECPELLA 5.5, 61.5% vs. Control, 53.8%, p = 0.691). Both total device complications (ECPELLA 5.5, 7.7% vs. Control, 46.1%, p = 0.021) and Impella-specific complications (ECPELLA 5.5, 0% vs. Control, 30.8%, p = 0.012) were significantly lower in the ECPELLA 5.5 group.

CONCLUSIONS

Utilization of Impella 5.5 in the setting of ECPELLA provides greater hemodynamic support with a lower risk of complications compared to Impella CP or 2.5.

Trends and Outcomes of Cardiogenic Shock in Patients With End-Stage Renal Disease: Insights From USRDS Database

BACKGROUND

There is a paucity of data regarding epidemiology, temporal trends, and outcomes of patients with cardiogenic shock (CS) and end-stage renal disease (chronic kidney disease stage V on hemodialysis).

METHODS

This is a retrospective cohort study using the United States Renal Data System database from January 1, 2006 to December 31, 2019. We analyzed trends of CS, percutaneous mechanical support (intraaortic balloon pump, percutaneous ventricular assist device [Impella and Tandemheart], and extracorporeal membrane oxygenation) utilization, index mortality, 30-day mortality, and 1-year all-cause mortality in end-stage renal disease patients.

RESULTS

A total of 43 825 end-stage renal disease patients were hospitalized with CS (median age, 67.8 years [IQR, 59.4-75.8] and 59.1% men). From 2006 to 2019, the incidence of CS increased from 275 to 578 per 100 000 patients (Ptrend<0.001). The index mortality rate declined from 54.1% in 2006 to 40.8% in 2019 (Ptrend=0.44), and the 1-year all-cause mortality decreased from 63% in 2006 to 61.8% in 2018 (Ptrend=0.73), but neither trend was statistically significant. There was a significantly decreased utilization of intra-aortic balloon pumps from 17 832 to 7992 (Ptrend<0.001), increased utilization of percutaneous ventricular assist device from 137 to 5201 (Ptrend<0.001) and increase in extracorporeal membrane oxygenation use from 69 to 904 per 100 000 patients (Ptrend<0.001). After adjusting for covariates, there was no significant difference in index mortality between CS patients requiring percutaneous mechanical support versus those not requiring percutaneous mechanical support (odds ratio, 0.97 [CI, 0.91-1.02]; P=0.22). On multivariable regression analysis, older age, peripheral vascular disease, diabetes, and time on dialysis were independent predictors of higher index mortality.

CONCLUSIONS

The incidence of CS in end-stage renal disease patients has doubled without significant change in the trend of index mortality despite the use of percutaneous mechanical support.

Cell-scale hemolysis evaluation of intervenient ventricular assist device based on dissipative particle dynamics

Most of the existing hemolysis mechanism studies are carried out on the macro flow scale. They assume that the erythrocyte membranes with different loads will suffer the same damage, which obviously has limitations. Thus, exploring the hemolysis mechanism through the macroscopic flow field information is a tough challenge. In order to further understand the non-physiological shear hemolysis phenomenon at the cell scale, this study used the coarse-grained erythrocytes damage model at the mesoscopic scale based on the transport dissipative particle dynamics (tDPD) method. Combined with computational fluid dynamics the hemolysis of scalarized shear stress (τ) in the clearance of "Impella 5.0" was evaluated under the Lagrange perspective and Euler perspective. The results from the Lagrange perspective showed that the change rate of scaled shear stress (τ˙) was the most critical factor in damaging RBCs in the rotor region of "Impella 5.0"and other transvalvular micro-axial blood pumps. Then, we propose a dimensionless number Dk with time integration based on τ˙ to evaluate hemolysis. The Dissipative particle dynamics simulation results are consistent with the Dk evaluation results, so τ˙ may be an important factor in the hemolysis of VADs. Finally, we tested the hemolysis of 30% hematocrit whole blood in the "Impella 5.0" shroud clearance from the Euler perspective. Relevant results indicate that because of the wall effect, the RBCs near the impeller side are more prone to damage, and most of the cytoplasm is also gathered at the rotor side.

Outcomes of surgical Impella placement in acute cardiogenic shock

Introduction

Although a role for percutaneous Impella devices has been established, there is a paucity of data regarding the utility and outcomes of larger surgically implanted Impella devices.

Methods

We conducted a retrospective review of all surgical Impella implants at our institution. All Impella 5.0 and Impella 5.5 devices were included. The primary outcome was survival. Secondary outcomes included hemodynamic and end-organ perfusion as well as commonly encountered surgical complications.

Results

From 2012 to 2022, 90 surgical Impella devices were implanted. The median age was 63 [53-70] years, the mean creatinine was 2.07 ± 1.22 mg/dL, and the average lactate level was 3.32 ± 2.90 mmol/L. Prior to implantation, 47 patients (52%) were supported with vasoactive agents, while 43 (48%) were also supported with another device. The most common etiology of shock was acute on chronic heart failure (50, 56%), followed by acute myocardial infarction (22, 24%), and postcardiotomy (17, 19%). Overall, 69 patients (77%) survived to device removal, and 57 (65%) survived to hospital discharge. One-year survival was 54%. Neither etiology of heart failure nor device strategy was associated with 30-day or 1-year survival. On multivariable modeling, the number of vasoactive medications prior to device implantation was strongly associated with 30-day mortality (hazard ratio 1.94 [1.27-2.96], P < 0.01). Surgical Impella placement was associated with a significant decreased need for vasoactive infusions (P < 0.01) and decreased acidosis (P = 0.01).

Conclusions

Surgical Impella support for patients in acute cardiogenic shock is associated with lower vasoactive medication use, improved hemodynamics, increased end-organ perfusion, and acceptable morbidity and mortality.

Impella 5.0/5.5 Implantation via Innominate Artery: Further Expanding the Opportunities for Temporary Mechanical Circulatory Support

When axillary/subclavian arteries are not suitable because of size or anatomy, alternative access for the Impella pump 5.0/5.5 via the innominate artery allows circulatory support and eventually de-escalation from VA-ECMO to isolated left-side support. Moreover, less invasive surgery without the need to open the pericardium reduces the risk of RV dysfunction and bleeding. Finally, upper body strategies allow early rehabilitation during support, which is associated with improved survival in cardiogenic shock.

Use of Impella device in cardiogenic shock and its clinical outcomes: A systematic review and meta-analysis

Introduction

Cardiogenic shock (CS) is a life-threatening condition and mechanical circulatory support (MCS) might exert a relevant impact on its clinical course. Among MCS devices, Impella is very promising. Yet, its usefulness is still debated. We performed a meta-analysis of all studies evaluating the clinical impact of Impella in CS.

Methods

All studies including patients with CS and treated with Impella were included. The primary endpoint was short-term mortality. Secondary endpoints were vascular access complications and major bleeding. Data synthesis was obtained using random-effects metanalysis.

Results

Thirty-three studies and 5204 patients were included. Short-term mortality was 47%. Meta-regression analysis showed that patients age (p = 0.01), higher support level (p = 0.004) and pre-PCI insertion (p < 0.001) were significant moderators for the primary endpoint. Vascular access complications were registered in 6.4% of cases, whereas age (p = 0.05) and diabetes (p = 0.007) were significant predictors. Major bleeding occurred in 16.4% of patients. Meta-analysis of the subgroup of studies comparing Impella to IABP showed no significant difference in short-term mortality (RR = 1.08, p = 0.45), while rates of vascular access complications (p < 0.001) or major bleeding (p < 0.001) were significantly higher with Impella. Subgroup and metaregression analyses showed that these results were influenced by lower adoption rates of higher degree of MCS support (p = 0.003), and by higher vascular complications rates (p = 0.014).

Conclusions

Our results suggest that the choice of adequate device size, careful patients selection and optimal timing of MCS initiation are key to clinical success with Impella in CS. Large prospective studies are mandatory to confirm these results deriving from retrospective studies.

ECMO and Impella Support Strategies as a Bridge to Surgical Repair of Post-Infarction Ventricular Septal Rupture

Background and Objectives: Post-infarct ventricular septal rupture (PIVSR) continues to have significant morbidity and mortality, despite decreased prevalence. Impella and venoarterial extracorporeal membranous oxygenation (VA-ECMO) have been proposed as strategies to correct hemodynamic derangements and bridge patients to delayed operative repair when success rates are higher. This review places VA-ECMO and Impella support strategies in the context of bridging patients to successful PIVSR repair, with an additional case report of successful bridging with the Impella device. Materials and Methods: We report a case of PIVSR repair utilizing 14 days of Impella support. We additionally conducted a systematic review of contemporary literature to describe the application of VA-ECMO and Impella devices in the pre-operative period prior to surgical PIVSR correction. Expert commentary on the advantages and disadvantages of each of these techniques is provided. Results: We identified 19 studies with 72 patients undergoing VA-ECMO as a bridge to PIVSR repair and 6 studies with 11 patients utilizing an Impella device as a bridge to PIVSR repair. Overall, outcomes in both groups were better than expected from patients who were historically managed with medicine and balloon pump therapy, however there was a significant heterogeneity between studies. Impella provided for excellent left ventricular unloading, but did result in some concerns for reversal of shunting. VA-ECMO resulted in improved end-organ perfusion, but carried increased risks of device-related complications and requirement for additional ventricular unloading. Conclusions: Patients presenting with PIVSR in cardiogenic shock requiring a MCS bridge to definitive surgical repair continue to pose a challenge to the multidisciplinary cardiovascular team as the diverse presentation and management issues require individualized care plans. Both VA-ECMO and the Impella family of devices play a role in the contemporary management of PIVSR and offer distinct advantages and disadvantages depending on the clinical scenario. The limited case numbers reported demonstrate feasibility, safety, and recommendations for optimal management.