The role of the axillary Impella 5.0 device on patients with acute cardiogenic shock

Use of Intravascular Micro-Axial Left Ventricular Assist Devices as a Bridging Strategy for Cardiogenic Shock: Mid-Term Outcomes

Objectives: Patients in cardiogenic shock (CS) may be successfully bridged using intravascular micro-axial left ventricular assist devices (M-LVADs) for recovery or determination of definitive therapy. Methods: One hundred and seven CS patients implanted with M-LVADs from January 2020 to May 2024 were divided into four groups; group-1: 34 patients (transplant); group-2: 25 patients (LVAD); group-3: 42 patients (postcardiotomy CS (PCCS)); group-4: 6 patients (decision/recovery but excluded from analysis). Multivariable logistic regression and Multivariable Coxregression models identified predictors of early -hospital and late mortality, and Odds ratios (ORs) and hazard ratios (HRs) with p < 0.05, respectively, were considered statistically significant. SPSS 29.0 and Python 3.11.1. were used for analyses. Results: Complications included device-malfunction (6%), gastrointestinal bleed (9%), long-term hemodialysis (21%), axillary hematoma requiring re-exploration (10%), heparin-induced thrombocytopenia (4%) requiring heparin therapy cessation/initiation of argatroban infusion, and non-fatal stroke (11%). Early hospital mortality included 13 patients: 2 in group-1, 1 in group-2, 10 in group-3 (p = 0.02). In the Logistic-Regression model, category of CS requiring an M-LVAD was significant (OR = 4.7, p = 0.05). Patients were followed for 4.5 years (mean follow-up was 23 ± 17 months), and 23 deaths occurred; group-1: 3 patients, group-2: 5 patients, and group-3: 15 patients (p = 0.019). At 4.5 years, actuarial survival was 90.7 ± 5.1% in group-1, 79.2 ± 8.3% in group-2, 62.8 ± 7.7% in group-3 (p = 0.01). In the Cox-Regression model, M-LVAD category (HR = 3.63, p = 0.04), and long-term postoperative dialysis (HR = 3.9, p = 0.002) emerged as predictors of long-term mortality. Conclusions: In cardiogenic shock, mid-term outcomes demonstrate good survival with M-LVADs as bridge to transplant/durable LVADs and reasonable survival with M-LVADs as a bridge to recovery following cardiotomy, accompanied by reduced ECMO usage, and early ambulation/rehabilitation.

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 5.5: A Systematic Review of the Current Literature

OBJECTIVE

Impella 5.5 (Abiomed, Danvers, MA, USA) is a temporary mechanical circulatory support device used for patients in cardiogenic shock. This review provides a comprehensive overview of the device's clinical effectiveness, safety profile, patient outcomes, and relevant procedural considerations.

METHODS

We conducted a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed/MEDLINE database. The search query included articles available from October 6, 2022, through January 13, 2023. Our initial search identified 75 studies. All records were screened by 2 independent reviewers using the Covidence software for adherence to our inclusion criteria, and 8 retrospective cohort studies were identified as appropriate for inclusion.

RESULTS

Across the included studies, the sample size ranged from 4 to 275, with predominantly male cohorts. Indications for Impella support varied, and the duration of support ranged from 9.8 to 70 days. Overall, Impella support appeared to be associated with favorable survival rates and manageable complications in various patient populations. Complications associated with Impella use included bleeding, stroke, and device malfunctions. Two studies compared prolonged and Food and Drug Administration-approved Impella support, showing similar outcomes and adverse events.

CONCLUSIONS

Impella 5.5 continues to be an attractive option for bridging patients to definitive therapy. Survival during and after Impella 5.5 was favorable for patients regardless of initial indication. However, device use was associated with several important complications, which calls for judicious use and a precontemplated exit strategy. Limitations of this literature review include biases inherent to the retrospective studies included, such as selection and publication bias.

Increasing waiting times for status 2 patients in new United Network for Organ Sharing allocation system: Impact on waitlist and posttransplant outcomes

OBJECTIVE

Since the heart transplant allocation policy change in 2018, there has been an increase in temporary mechanical circulatory support for Status 2 patients. We sought to examine the temporal pattern of waitlist and posttransplant outcomes for Status 2 patients.

METHODS

Adult patients in the United Network for Organ Sharing registry who were listed as Status 2 from January 2019 to June 2022 were included. Temporal trends in waitlist time, waitlist events, and posttransplant outcomes were assessed. Probability of transplant or death after being listed was compared over time. Multivariable regression was performed to identify risk factors for mortality after transplant.

RESULTS

A total of 6310 patients were included. From 2019 to 2022, the number of Status 2 patients listed increased from 4.2 to 5.9 per day. Microaxial ventricular assist devices at Status 2 listing increased over time (P < .001). During the study period, median waitlist time (18 days vs 23 days, P < .001) as well as Status 2 days (8 days vs 12 days, P < .001) increased. Waitlist mortality remained stable (5.5%); however, probability of transplant within 90 days of Status 2 listing progressively declined (P < .001). Finally, longer waitlist duration was independently associated with 30-day posttransplant mortality (odds ratio, 1.01; 95% confidence interval, 1.00-1.01, P = .02).

CONCLUSIONS

Since the allocation policy change there has been a steady rise in the number of patients listed for Status 2. This has led to increasing waitlist times and lower probability of transplantation for Status 2 patients, which may have negative consequences for posttransplant outcomes.

Clinical outcomes of hundred large Impella implantations in cardiogenic shock patients based on individual clinical scenarios

BACKGROUND

Large Impella systems (5.0 or 5.5; i.e., Impella 5+) (Abiomed Inc., Danvers, MA, USA) help achieve better clinical outcomes through relevant left ventricular unloading in acute cardiogenic shock (CS). Here, we report our experience with Impella 5+, while focusing on the clinical outcomes depending on individual case scenarios in patients with acute CS.

METHODS

This single-center retrospective observational study included 100 Impella 5+ implantations conducted on patients with acute CS from November 2018 to October 2021. After excluding 10 reimplantation cases, 90 cases were enrolled for further analysis.

RESULTS

In-hospital and 30-day mortality rates were 56.7% (n = 51) and 48.9% (n = 44), respectively. In-hospital mortality was lower in patients with acute myocardial infarction (AMI) than in non-AMI patients (p = 0.07). Young age and low lactate levels were the independent predictors of successful transition and survival after permanent mechanical circulatory support/heart transplantation (pMCS/HTX) (age, p = 0.03; lactate level, p = 0.04; survived after pMCS/HTX, n = 11; died on Impella, n = 41). During simultaneous utilization of venoarterial extracorporeal membrane oxygenation therapy and Impella 5+, termed ECMELLA therapy, high dose of noradrenaline was a predictive factor for in-hospital mortality by multivariate analysis (n = 0.02).

CONCLUSIONS

Our results suggest that enhanced Impella support might have better clinical outcomes among acute CS patients supported with large Impella, those with AMI than those with no AMI. Young age and low lactate levels were predictors of successful bridging to pMCS/HTX and favorable clinical outcomes thereafter. The clinical outcomes of ECMELLA therapy might depend on noradrenaline dose at the time of Impella 5+ implantation.

Extended Support With the Impella 5.5: Transplant, ECMO, and Complications

We report midterm results of Impella 5.5 use with focus placed on bridge-outcomes, venoarterial extracorporeal membrane oxygenation (VA-ECMO) transition, complications, and risk factors for mortality. A retrospective review of patients implanted with the Impella 5.5 at our medical center was conducted. Forty patients were included with varying bridge strategies. Sixteen (40%) patients were supported for <14 days, 13 (32.5%) for 14-30 days, and 11 (27.5%) for >30 days. Thirty day mortality was 22.5% (9/40). Twenty-five (62.5%) were successfully bridged to transplant or durable left ventricular assist device (LVAD), while four (10.0%) recovered without the need for any further cardiac support. Five of 11 (60%) patients initially supported with VA-ECMO were either transitioned to durable left ventricular assist device (dLVAD; n = 3, 27.3%), transplanted (n = 1, 9.1%), or recovered (n = 1, 9.1%). Of nine patients with >moderate right ventricle (RV) dysfunction, five (55.6%) were successfully bridged to transplant or LVAD. Five (12.5%) patients required interval cannulation to VA-ECMO, often in the setting of RV dysfunction, and all (100%) were successfully transplanted. Lower pulmonary artery (PA) systolic pressure ( P = 0.029), among other factors, was associated with mortality. In summary, the Impella 5.5 may be able to effectively stabilize patients in refractory left ventricular predominant cardiogenic shock for extended durations, allowing time for mechanical circulatory support (MCS) and transplant evaluations.

Increased risk of purge system malfunction after Impella 5.0 replacement: a case series

The Impella 5.0 is an axial-flow percutaneous ventricular assist device used in patients with cardiogenic shock. Although the recommended period of use is 10 days or less, weaning can be delayed because of ongoing hemodynamic instability. In clinical practice, this device sometimes malfunctions during long-term management with heparin and must be replaced; however, the relationship between the duration of support with the initial and replacement Impella 5.0 and the changes in value of the purge system has not been fully elucidated. From July 2018 to May 2021, Impella 5.0 was implanted and used for more than 10 days in 11 patients at our institution. Four patients required Impella replacement because of device malfunction and the second Impella had purge system malfunction in all cases. The second Impella was used for a significantly shorter time than the first Impella (p = 0016). We calculated the ratio of purge pressure to purge flow rate and found that the ratio exceeded 50 mm Hg/mL/h in all cases with purge system malfunction. In conclusion, it is important to construct a treatment strategy considering the duration of use, because the risk of purge system malfunction is high after replaced Impella 5.0.

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.

The Therapeutic Use of Impella Device in Cardiogenic Shock: A Systematic Review

Impella (Abiomed, Danvers, MA) devices nowadays have been linked to cardiogenic shock (CS) due to the importance of their use as therapeutic instruments. This study aims to review pathophysiologic mechanisms of cardiogenic shock and the implementation of Impella to overcome this condition. To investigate several different types of studies and analyze the use of Impella device in cardiogenic shock and the outcomes of heart malfunctioning and determine its positive and negative impacts as a therapeutic tool in cardiac ischemia and use as a resource in critical patients, we conducted a systematic review through different databases (PubMed, ScienceDirect, and Google Scholar) following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist and used the Medical Subjects Heading (MeSH) search strategy to obtain significant articles. We found 883 papers in total, and after removing duplicates, applying inclusion/exclusion criteria, and finding the most significant information, we ended up with 30 articles that were reviewed containing information about the impact of Impella device in cardiogenic shock in different locations. The study strongly concludes that Impella device in the setting of cardiogenic shock has more advantages than disadvantages in terms of outcomes and complications as a non-pharmacologic tool. Improvements in left ventricular ejection fraction and signs and symptoms of cardiogenic shock criteria were determinants. Nevertheless, complications during the implementation and use of the device were established; in this manner, the evaluation and treatment of each patient separately are imperative. Consequently, more studies on this relevant topic are needed.

Impella 5.5 Support beyond 50 Days as Bridge to Heart Transplant in End-Stage Heart Failure Patients

Prolonged mechanical circulatory support (MCS) for severe left ventricular dysfunction in cardiogenic shock as a bridge to heart transplantation (HTx) generally requires a surgical procedure. Typically, a surgically implanted temporary extracorporeal left ventricular assist device (LVAD) is chosen because of superior flow and durability compared with a percutaneously delivered endovascular LVAD (pVAD). However, compared with its predecessors, the Impella 5.5 trans-valvular pVAD provides higher hemodynamic support and features improved durability. Here, we present four successful cases with prolonged Impella 5.5 support as a bridge to HTx, with a mean support duration of 70 days (maximum 83 days). These cases highlight several potential benefits of Impella 5.5. The minimally invasive implantation procedure of the device reduces bleeding, decreases the postoperative recovery period, and enables early patient ambulation to reduce physical deconditioning before HTx surgery. Furthermore, Impella 5.5 adequately unloads the left ventricle and provides hemodynamic support to maintain end-organ function to further optimize hemodynamics before HTx. The evolution of Impella 5.5 technology may provide an alternative bridging strategy to traditional surgically implanted temporary MCS in select cases.

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 5.0 is associated with a reduction in vasoactive support and improves hemodynamics in cardiogenic shock: A single-center experience

BACKGROUND

Treatment of cardiogenic shock (CS) often requires the use of vasopressors and inotropic agents, which are associated with an increase in mortality. Data on change in vasopressor and inotrope requirements post Impella 5.0 placement is scarce. Thus, we aimed to study the ability of Impella 5.0 to reduce these requirements.

METHODS

Retrospective analysis of consecutive patients with CS receiving Impella 5.0 was performed. Vasopressor-Inotrope Score (VIS) and a Modified Catecholamine Equivalent score (MCES) was calculated prior to and up to 72 h post-Impella implantation. Primary outcome was change in MCES from baseline to 48-h post implantation and secondary outcomes included change in VIS, changes in MCES according to SCAI Stage and to underlying etiology, and freedom from mortality at 30-days.

RESULTS

Twenty-eight patients with median age of 61 (48, 67) years were included. Impella 5.0 was associated with significant reduction in MCES from baseline [9.7 (5.3, 17)] to 48 h [5.7 (3.8, 7.5), p = 0.001]. VIS was also significantly reduced from baseline [8.3 (3.8, 19.9)] to 48 h [5.0 (2.5, 8), p = 0.003]. MCES at 48 h was significantly reduced in patients with SCAI Stage E versus Stage C (p = 0.026) and with acute myocardial infarction versus acute decompensated heart (p = 0.003). Thirty-day survival was 0% in patients that had a baseline MCES ⩾ 10 without a reduction in MCES of at least 5 at 24 h.

CONCLUSION

Impella 5.0 is associated with a significant reduction in MCES and VIS scores in patients presenting with CS with 30-day survival being dependent on MCES.

A Meta-Analysis Comparing Venoarterial (VA) Extracorporeal Membrane Oxygenation (ECMO) to Impella for Acute Right Ventricle Failure

The right ventricular complication happens when the right ventricle (RV) fails to move sufficient blood through the pulmonary circle to enable enough left ventricular pumping. A significant pulmonary embolism/right-sided myocardial infarction may cause this to develop suddenly in a previously healthy heart, but many of the patients treated in the critical care unit have gradual, compensated RV failure as a result of chronic heart and lung disease. RV failure management aims to decrease afterload and improve right-side filling pressures. Vasoactive medications have a lower effect on lowering vascular obstruction in the pulmonary circulation than in the systemic circle because the vascular tone is lower in the pulmonary circulation. Any factors that induce an elevation in pulmonary vascular tone must be addressed, and selective pulmonary vasodilators must be administered in a prescription that does not result in systemic hypotension or compromise oxygenation. The system-based systolic arterial pressure should be kept near the RV systolic pressure to ensure RV perfusion. When these efforts prove futile, judicious application of inotropic medications for better RV contractility may help ensure cardiac output. After obtaining the finest medical treatment, certain individuals may need the implantation of a mechanical circulatory support device. This meta-analysis is intended to compare the Impella and venoarterial (VA) extracorporeal membrane oxygenation (ECMO) mechanical supports for patients with acute right ventricular failure. This comparison should demonstrate the best mechanical support between the two through thorough analysis. The analysis was begun by data collection from relevant sites; PUBMED and EMBASE were searched in collaboration with Google Scholar. Keywords were searched: Impella for acute right ventricle failure and VA ECMO for acute right ventricle failure. The results that were close to the search titles had their respective articles downloaded for further scrutiny. The search finally brought 1001 related articles that were exposed to further analysis to find more refined and closer articles within the needs of this meta-analysis. After extensive scrutiny, 23 articles were found to be the best for these analyses. The data showed that VA ECMO had better results than Impella for acute RV failure. However, the data were not statistically significant, as either the numbers of the studies were not enough or the null hypothesis was true and there was no true difference between them. More studies will be needed to confirm this.

Novel method for transaxillary Impella 5.0 implantation in patients with tortuous arterial anatomy

A novel method of transaxillary Impella 5.0 implantation utilizing a vascular sheath can overcome difficult arterial anatomy and provide mechanical support for patients in critical cardiogenic shock.

Hemodynamic Changes During Neuromuscular Electrical Stimulation and Mobility Therapy for an Advanced Heart Failure Patient with Impella 5.0 Device

The Impella 5.0 is a catheter-mounted left ventricular assist device that is inserted through the patient's subclavian artery. This device allows patient mobilization. Early mobility improves outcomes, including physical function and exercise tolerance, in critically ill patients and those with heart failure (HF). However, there have been no studies regarding the safety of early mobilization during the period of Impella 5.0 insertion based on hemodynamic assessment.A 39-year-old man with idiopathic dilated cardiomyopathy and cardiogenic shock was transferred to our hospital for Impella 5.0 insertion. We started neuromuscular electrical stimulation (NMES) and mobilization eight days after Impella 5.0 insertion. The safety of NMES and mobilization was assessed based on mean blood pressure, heart rate (HR), and mean pulmonary artery pressure measurements as hemodynamic indicators. Muscle strength was also assessed using the Medical Research Council (MRC) scale. Throughout the interventions, only the HR increased slightly during mobilization, and there were no hemodynamic abnormalities. Also, the MRC scale score improved as mobilization progressed. The results presented here suggest that NMES and mobilization are safe and feasible in patients with Impella 5.0 insertion, and therefore should be widely adopted.

ECPella: Concept, Physiology and Clinical Applications

Addition of Impella on top of venoarterial extracorporeal membrane oxygenation (VA-ECMO) has gained wide interest as it might portend improved outcomes in patients with cardiogenic shock. This has been consistently reported in retrospective propensity-matched studies, case series, and meta-analyses. The pathophysiologic background is based on the mitigation of ECMO-related side effects and the additive benefit of myocardial unloading. In this perspective, thorough knowledge of these mechanisms is required to optimize the management of mechanical circulatory support with this approach and introduce best practices, as the interplay between the two devices and the implantation-explantation strategies are key for success.