The Evolving Landscape of Impella Use in the United States Among Patients Undergoing Percutaneous Coronary Intervention With Mechanical Circulatory Support

Intra-aortic balloon pump is associated with the lowest whereas Impella with the highest inpatient mortality and complications regardless of severity or hospital types

Impella and intra-aortic balloon pumps (IABP) are commonly utilized in patients with cardiogenic shock. However, the effect on mortality remains controversial. The goal of this study was to evaluate the effect of Impella and IABP on mortality in patients with cardiogenic shock the large Nationwide Inpatient Sample (NIS) database was utilized to study any association between the use of IABP or Impella on outcome. ICD-10 codes for Impella, IABP, and cardiogenic shock for available years 2016-2020 were utilized. A total of 844,020 patients had a diagnosis of cardiogenic shock. A total of 101,870 patients were treated with IABP and 39645 with an Impella. Total inpatient mortality without any device was 34.2% vs only 25.1% with IABP use (OR = 0.65, CI 0.62-0.67) but was highest at 40.7% with Impella utilization (OR = 1.32, CI 1.26-1.39). After adjusting for 47 variables, Impella utilization remained associated with the highest mortality (OR: 1.33, CI 1.25-1.41, p < 0.001), whereas IABP remained associated with the lowest mortality (OR: 0.69, CI 0.66-0.72, p < 0.001). Separating rural vs teaching hospitals revealed similar findings. In patients with cardiogenic shock, the use of Impella was associated with the highest whereas IABP was associated with the lowest in-hospital mortality regardless of comorbid condition.

Outcomes of Impella 5.0 and 5.5 for cardiogenic shock: A single-center 137 patient experience

BACKGROUND

This study evaluated the outcomes of patients with cardiogenic shock (CS) supported with Impella 5.0 or 5.5 and identified risk factors for in-hospital mortality.

METHODS

Adults with CS who were supported with Impella 5.0 or 5.5 at a single institution were included. Patients were stratified into three groups according to their CS etiology: (1) acute myocardial infarction (AMI), (2) acute decompensated heart failure (ADHF), and (3) postcardiotomy (PC). The primary outcome was survival, and secondary outcomes included adverse events during Impella support and length of stay. Multivariable logistic regression was performed to identify risk factors for in-hospital mortality.

RESULTS

One hundred and thirty-seven patients with CS secondary to AMI (n = 47), ADHF (n = 86), and PC (n = 4) were included. The ADHF group had the highest survival rates at all time points. Acute kidney injury (AKI) was the most common complication during Impella support in all 3 groups. Increased rates of AKI and de novo renal replacement therapy were observed in the PC group, and the AMI group experienced a higher incidence of bleeding requiring transfusion. Multivariable analysis demonstrated diabetes mellitus, elevated pre-insertion serum lactate, and elevated pre-insertion serum creatinine were independent predictors of in-hospital mortality, but the etiology of CS did not impact mortality.

CONCLUSIONS

This study demonstrates that Impella 5.0 and 5.5 provide effective mechanical support for patients with CS with favorable outcomes, with nearly two-thirds of patients alive at 180 days. Diabetes, elevated pre-insertion serum lactate, and elevated pre-insertion serum creatinine are strong risk factors for in-hospital mortality.

Usefulness of bicarbonate-based Impella purge solution in a patient with heparin-induced thrombocytopenia: the first case report of long-term management in Japan

Percutaneous mechanical circulatory support utilizing micro-axial flow pumps, such as the Impella group of devices, has become a life-saving technique in the treatment of refractory cardiogenic shock, with ever-increasing success rates. A 30-year-old man presented with acute decompensated heart failure and a severely reduced left ventricular ejection fraction (17%). Despite initial treatment with inotropic drugs and intra-aortic balloon pump support, his hemodynamic status remained unstable. Transition to Impella CP mechanical circulatory support was made on day 6 owing to persistently low systolic blood pressure. A significant decline in platelet count prompted suspicion of heparin-induced thrombocytopenia (HIT), later confirmed by positive platelet-activated anti-platelet factor 4/heparin antibody and a 4Ts score of 6 points. Argatroban was initially used as the purge solution, but owing to complications, a switch to Impella 5.0 and a bicarbonate-based purge solution (BBPS) was performed. Despite additional veno-arterial extracorporeal membrane oxygenation support on day 24, the patient, aiming for ventricular assist device treatment and heart transplantation, died from infection and multiple organ failure. Remarkably, the Impella CP continued functioning normally until the patient's demise, indicating stable Impella pump performance using BBPS. This case highlights the usefulness of BBPS as an alternative to conventional Impella heparin purge solution when HIT occurs.

Percutaneous Microaxial Ventricular Assist Device Versus Intra-Aortic Balloon Pump for Nonacute Myocardial Infarction Cardiogenic Shock

BACKGROUND

Evidence on the comparative outcomes following percutaneous microaxial ventricular assist devices (pVAD) versus intra-aortic balloon pump for nonacute myocardial infarction cardiogenic shock is limited.

METHODS AND RESULTS

We included 704 and 2140 Medicare fee-for-service beneficiaries aged 65 to 99 years treated with pVAD and intra-aortic balloon pump, respectively, for nonacute myocardial infarction cardiogenic shock from 2016 to 2020. Patients treated using pVAD compared with those treated using intra-aortic balloon pump were more likely to be concurrently treated with mechanical ventilation, renal replacement therapy, and blood transfusions. We computed propensity scores for undergoing pVAD using patient- and hospital-level factors and performed a matching weight analysis. The use of pVAD was associated with higher 30-day mortality (adjusted odds ratio, 1.92 [95% CI, 1.59-2.33]) but not associated with in-hospital bleeding (adjusted odds ratio, 1.00 [95% CI, 0.81-1.24]), stroke (adjusted odds ratio, 0.91 [95% CI, 0.56-1.47]), sepsis (OR, 0.91 [95% CI, 0.64-1.28]), and length of hospital stay (adjusted mean difference, +0.4 days [95% CI, -1.4 to +2.3]). A quasi-experimental instrumental variable analysis using the cross-sectional institutional practice preferences showed similar patterns, though not statistically significant (adjusted odds ratio, 1.38; 95% CI, 0.28-6.89).

CONCLUSIONS

Our investigation using the national sample of Medicare beneficiaries showed that the use of pVAD compared with intra-aortic balloon pump was associated with higher mortality in patients with nonacute myocardial infarction cardiogenic shock. Providers should be cautious about the use of pVAD for nonacute myocardial infarction cardiogenic shock, while adequately powered high-quality randomized controlled trials are warranted to determine the clinical effects of pVAD.

Unloading in cardiogenic shock: the rationale and current evidence

PURPOSE OF REVIEW

Discussing the rationale and current evidence for left ventricular unloading in cardiogenic shock.

RECENT FINDINGS

Microaxial flow pumps (MFP) and intra-aortic balloon pumps (IABP) augment cardiac output while simultaneously unloading the left ventricle (LV, e.g. reducing left ventricular pressure), thereby targeting a key mechanism of cardiogenic shock. A recent randomized trial has shown a mortality reduction with MFP in selected patients with cardiogenic shock, strengthening the rationale for this strategy, although the evidence for the IABP is so far neutral. MFP/IABP can also be used concomitantly with veno-arterial extracorporeal membrane oxygenation (va-ECMO) to alleviate the va-ECMO-related increase in left ventricular afterload, to facilitate weaning and ultimately to improve myocardial recovery and prognosis of affected patients. However, the use of MFP/IABP in this indication solely relies on retrospective data, which need to be interpreted with caution, especially as these strategies are associated with more complications. Currently ongoing randomized trials will help to further clarify the role of left ventricular unloading in patients on va-ECMO.

SUMMARY

Left ventricular unloading addresses a key mechanism of cardiogenic shock, with strong evidence to support MFP use in selected patients, but further randomized controlled trials are required to clarify the role of different devices/strategies for the overall shock population.

Stroke outcomes following durable left ventricular assist device implant in patients bridged with micro-axial flow pump: Insights from a large registry

BACKGROUND

Stroke after durable left ventricular assist device (d-LVAD) implantation portends high mortality. The incidence of ischemic and hemorrhagic stroke and the impact on stroke outcomes of temporary mechanical circulatory support (tMCS) management among patients requiring bridge to d-LVAD with micro-axial flow-pump (mAFP, Abiomed) is unsettled.

METHODS

Consecutive patients, who underwent d-LVAD implantation after being bridged with mAFP at 19 institutions, were retrospectively included. The incidence of early ischemic and hemorrhagic stroke after d-LVAD implantation (<60 days) and association of pre-d-LVAD characteristics and peri-procedural management with a specific focus on tMCS strategies were studied.

RESULTS

Among 341 patients, who underwent d-LVAD implantation after mAFP implantation (male gender 83.6%, age 58 [48-65] years, mAFP 5.0/5.5 72.4%), the early ischemic stroke incidence was 10.8% and early hemorrhagic stroke 2.9%. The tMCS characteristics (type of mAFP device and access, support duration, upgrade from intra-aortic balloon pump, ECMELLA, ECMELLA at d-LVAD implantation, hemolysis, and bleeding) were not associated with ischemic stroke after d-LVAD implant. Conversely, the device model (mAFP 2.5/CP vs. mAFP 5.0/5.5: HR 5.6, 95%CI 1.4-22.7, p = 0.015), hemolysis on mAFP support (HR 10.5, 95% CI 1.3-85.3, p = 0.028) and ECMELLA at d-LVAD implantation (HR 5.0, 95% CI 1.4-18.7, p = 0.016) were associated with increased risk of hemorrhagic stroke after d-LVAD implantation. Both early ischemic (HR 2.7, 95% CI 1.9-4.5, p < 0.001) and hemorrhagic (HR 3.43, 95% CI 1.49-7.88, p = 0.004) stroke were associated with increased 1-year mortality.

CONCLUSIONS

Among patients undergoing d-LVAD implantation following mAFP support, tMCS characteristics do not impact ischemic stroke occurrence, while several factors are associated with hemorrhagic stroke suggesting a proactive treatment target to reduce this complication.

Impact of Left Ventricular Unloading on Outcome of Heart Transplant Bridging With Extracorporeal Membrane Oxygenation Support in New Allocation Policy

BACKGROUND

The new heart allocation policy places veno-arterial extracorporeal membrane oxygenation (VA-ECMO)-supported heart transplant (HT) candidates at the highest priority status. Despite increasing evidence supporting left ventricular (LV) unloading during VA-ECMO, the effect of LV unloading on transplant outcomes following bridging to HT with VA-ECMO remains unknown.

METHODS AND RESULTS

From October 18, 2018 to March 21, 2023, 624 patients on VA-ECMO at the time of HT were identified in the United Network for Organ Sharing database and were divided into 2 groups: VA-ECMO alone (N=384) versus VA-ECMO with LV unloading (N=240). Subanalysis was performed in the LV unloading group: Impella (N=106) versus intra-aortic balloon pump (N=134). Recipient age was younger in the VA-ECMO alone group (48 versus 53 years, P=0.018), as was donor age (VA-ECMO alone, 29 years versus LV unloading, 32 years, P=0.041). One-year survival was comparable between groups (VA-ECMO alone, 88.0±1.8% versus LV unloading, 90.4±2.1%; P=0.92). Multivariable Cox hazard model showed LV unloading was not associated with posttransplant mortality after HT (hazard ratio, 0.92; P=0.70). Different LV unloading methods had similar 1-year survival (intra-aortic balloon pump, 89.2±3.0% versus Impella, 92.4±2.8%; P=0.65). Posttransplant survival was comparable between different Impella versions (Impella 2.5, versus Impella CP, versus Impella 5.0, versus Impella 5.5).

CONCLUSIONS

Under the current allocation policy, LV unloading did not impact waitlist outcome and posttransplant survival in patients bridged to HT with VA-ECMO, nor did mode of LV unloading. This highlights the importance of a tailored approach in HT candidates on VA-ECMO, where routine LV unloading may not be universally necessary.

Cardiogenic Shock Challenges and Priorities: A Clinician Survey

BACKGROUND

Cardiogenic shock (CS) is common and survival outcomes have not substantially improved. Australia's geography presents unique challenges in the management of CS. The challenges and research priorities for clinicians pertaining to CS identification and management have yet to be described.

METHOD

We used an exploratory sequential mixed methods design. Semi-structured interviews were conducted with 10 clinicians (medical and nursing) to identify themes for quantitative evaluation. A total of 143 clinicians undertook quantitative evaluation through online survey. The interviews and surveys addressed current understanding of CS, status of cardiogenic systems and future research priorities.

RESULTS

There were 143 respondents: 16 (11%) emergency, cardiology 22 (16%), 37 (26%) intensive care, 54 (38%) nursing. In total, 107 (75%) believe CS is under-recognised. Thirteen (13; 9%) of respondents indicated their hospital had existing CS teams, all from metropolitan hospitals, and 40% thought additional access to mechanical circulatory support devices was required. Five (5; 11%) non-tertiary hospital respondents had not experienced a delay in transfer of a patient in CS. All respondents felt additional research, particularly into the management of CS, was required.

CONCLUSIONS

Clinicians report that CS is under-recognised and further research into CS management is required. Access to specialised CS services is still an issue and CS protocolised pathways may be of value.

Management of patients with impella devices or intra-aortic balloon pumps during helicopter air ambulance transport in observational data

INTRODUCTION

Placement of percutaneous ventricular support devices such as an intraaortic balloon pump (IABP) or Abiomed Impella device can treat severe cardiogenic shock. Critical care transport medicine (CCTM) providers frequently manage patients supported by these devices during interfacility transfers, often using a helicopter air ambulance (HAA). An understanding of patient needs and management during transport is essential to informing crew configuration and training, and this study adds to the limited existing data on the HAA transport of this complex patient population.

METHODS

We performed a retrospective chart review of all HAA transports of patients with an IABP (n = 38) or Impella (n = 11) device at a single CCTM program from 2016 to 2020. We evaluated transport times and composite variables for the frequency of adverse events, condition changes requiring critical care evaluation, and critical care interventions.

RESULTS

In this observational cohort, patients with an Impella device more frequently had an advanced airway and at least 1 vasopressor or inotrope active prior to transport. While flight times were similar, CCTM teams remained at referring facilities longer for patients with an Impella device (99 vs 68 minutes; p = 0.0097). Compared to patients with an IABP, patients with an Impella device more frequently had a condition change requiring critical care evaluation (100% vs 42%; p = 0.0005) and more frequently received critical care interventions (100% vs 53%; p = 0.0037). Adverse events were uncommon and did not differ for patients with an Impella device compared to an IABP (27% vs 11%; p = 0.178).

CONCLUSION

Patients requiring mechanical circulatory support with IABP and Impella devices frequently require critical care management during transport. Clinicians should ensure the CCTM team has appropriate staffing, training, and resources to meet the critical care needs of these high acuity patients.

Predictors of Mortality in Acute Myocardial Infarction Complicated by Cardiogenic Shock despite Intra-Aortic Balloon Pump: Opportunities for Advanced Mechanical Circulatory Support in Asia

Introduction: Acute myocardial infarction complicated by cardiogenic shock (AMI-CS) mortality remains high despite revascularization and the use of the intra-aortic balloon pump (IABP). Advanced mechanical circulatory support (MCS) devices, such as catheter-based ventricular assist devices (cVAD), may impact mortality. We aim to identify predictors of mortality in AMI-CS implanted with IABP and the proportion eligible for advanced MCS in an Asian population. Methods: We retrospectively analyzed a cohort of Society for Cardiovascular Angiography and Intervention (SCAI) stage C and above AMI-CS patients with IABP implanted from 2017-2019. We excluded patients who had IABP implanted for indications other than AMI-CS. Primary outcome was 30-day mortality. Binary logistic regression was used to calculate adjusted odds ratios (aOR) for patient characteristics. Results: Over the 3-year period, 242 patients (mean age 64.1 ± 12.4 years, 88% males) with AMI-CS had IABP implanted. 30-day mortality was 55%. On univariate analysis, cardiac arrest (p < 0.001), inotrope/vasopressor use prior to IABP (p = 0.004) was more common in non-survivors. Non-survivors were less likely to be smokers (p = 0.001), had lower ejection fraction, higher creatinine/ lactate and lower pH (all p < 0.001). On multi-variate analysis, predictors of mortality were cardiac arrest prior to IABP (aOR 4.00, CI 2.28-7.03), inotrope/vasopressor prior to IABP (aOR 2.41, CI 1.18-4.96), lower arterial pH (aOR 0.02, CI 0.00-0.31), higher lactate (aOR 2.42, CI 1.00-1.19), and lower hemoglobin (aOR 0.83, CI 0.71-0.98). Using institutional MCS criteria, 106 patients (44%) would have qualified for advanced MCS. Conclusions: Early mortality in AMI-CS remains high despite IABP. Many patients would have qualified for higher degrees of MCS.

Impact of center volume on in-hospital mortality in adult patients with out‑of‑hospital cardiac arrest resuscitated using extracorporeal cardiopulmonary resuscitation: a secondary analysis of the SAVE-J II study

Recently, patients with out-of-hospital cardiac arrest (OHCA) refractory to conventional resuscitation have started undergoing extracorporeal cardiopulmonary resuscitation (ECPR). However, the mortality rate of these patients remains high. This study aimed to clarify whether a center ECPR volume was associated with the survival rates of adult patients with OHCA resuscitated using ECPR. This was a secondary analysis of a retrospective multicenter registry study, the SAVE-J II study, involving 36 participating institutions in Japan. Centers were divided into three groups according to the tertiles of the annual average number of patients undergoing ECPR: high-volume (≥ 21 sessions per year), medium-volume (11-20 sessions per year), or low-volume (< 11 sessions per year). The primary outcome was survival rate at the time of discharge. Patient characteristics and outcomes were compared among the three groups. Moreover, a multivariable-adjusted logistic regression model was applied to study the impact of center ECPR volume. A total of 1740 patients were included in this study. The center ECPR volume was strongly associated with survival rate at the time of discharge; furthermore, survival rate was best in high-volume compared with medium- and low-volume centers (33.4%, 24.1%, and 26.8%, respectively; P = 0.001). After adjusting for patient characteristics, undergoing ECPR at high-volume centers was associated with an increased likelihood of survival compared to middle- (adjusted odds ratio 0.657; P = 0.003) and low-volume centers (adjusted odds ratio 0.983; P = 0.006). The annual number of ECPR sessions was associated with favorable survival rates and lower complication rates of the ECPR procedure.Clinical trial registration: https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000041577 (unique identifier: UMIN000036490).

LifeFlight Case Studies: Lessons Learned From Notable Flights

Air medical providers are responsible for the care of an incredibly diverse patient population. When it is time to transport a patient, providers must be prepared for complex situations, each requiring different skills, medications, and critical thinking. Scene flights will have providers landing and providing care in the prehospital setting where an interfacility transport requires the patient to be taken from one hospital to another. Specialty flights require special equipment, personnel, and aircraft preparedness to be completed. The case studies provided within this article highlight the complexity and diversity that is encountered each shift at Allegheny LifeFlight.

Outcomes of Veno-Arterial Extracorporeal Membrane Oxygenation With Percutaneous Left Ventricular Unloading in Fulminant Myocarditis

Fulminant myocarditis requiring peripheral veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has a high mortality rate. We investigated clinical outcomes of combined use of VA-ECMO and percutaneous left ventricular assist device (VAD) (Impella) for fulminant myocarditis in 104 consecutive patients enrolled in the Japan Registry for Percutaneous VAD (J-pVAD) between October 2017 and January 2020. Patients were followed until hospital discharge and predictors of survival were analyzed with a Cox proportional hazards model. The median support duration of combined use of VA-ECMO and Impella (ECMO/Impella) was 6 days, and the median left ventricular ejection fraction improved from 15% to 52% during support ( p < 0.0001). Overall, 66 patients (63%) survived to discharge. Multivariate analysis revealed ECMO/Impella support at a transplant center as an independent predictor of survival ( p = 0.0231). Patients treated at transplant centers had better 60 days survival rates when compared to nontransplant centers (83% vs. 55%, p = 0.005). However, baseline characteristics and treatment strategies differed between the two groups. This real-world national registry database suggested the difference in survival after ECMO/Impella support for fulminant myocarditis between transplant and nontransplant centers, which may indicate hospital variations regarding patient management, although further controlled studies are needed.

Association between left ventricular ejection fraction, mortality and use of mechanical circulatory support in patients with non-ischaemic cardiogenic shock

BACKGROUND

Currently, use of mechanical circulatory support (MCS) in non-ischaemic cardiogenic shock (CS) is predominantly guided by shock-specific markers, and not by markers of cardiac function. We hypothesise that left ventricular ejection fraction (LVEF) can identify patients with a higher likelihood to benefit from MCS and thus help to optimise their expected benefit.

METHODS

Patients with non-ischaemic CS and available data on LVEF from 16 tertiary-care centres in five countries were analysed. Cox regression models were fitted to evaluate the association between LVEF and mortality, as well as the interaction between LVEF, MCS use and mortality.

RESULTS

N = 807 patients were analysed: mean age 63 [interquartile range (IQR) 51.5-72.0] years, 601 (74.5%) male, lactate 4.9 (IQR 2.6-8.5) mmol/l, LVEF 20 (IQR 15-30) %. Lower LVEF was more frequent amongst patients with more severe CS, and MCS was more likely used in patients with lower LVEF. There was no association between LVEF and 30-day mortality risk in the overall study cohort. However, there was a significant interaction between MCS use and LVEF, indicating a lower 30-day mortality risk with MCS use in patients with LVEF ≤ 20% (hazard ratio 0.72, 95% confidence interval 0.51-1.02 for LVEF ≤ 20% vs. hazard ratio 1.31, 95% confidence interval 0.85-2.01 for LVEF > 20%, interaction-p = 0.017).

CONCLUSION

This retrospective study may indicate a lower mortality risk with MCS use only in patients with severely reduced LVEF. This may propose the inclusion of LVEF as an adjunctive parameter for MCS decision-making in non-ischaemic CS, aiming to optimise the benefit-risk ratio.

Heparin dosing in patients with Impella-supported cardiogenic shock

BACKGROUND

Impella™ is increasingly used in cardiogenic shock. However, thromboembolic and bleeding events are frequent during percutaneous mechanical circulatory support (pMCS).

OBJECTIVE

Therefore, we aimed to explore the optimal anticoagulation regime for pMCS to prevent thromboembolism and bleedings.

METHODS

This hypothesis-generating multi-center cohort study investigated 170 patients with left-Impella™ support. We (A) compared bleeding/thrombotic events in two centers with therapeutic range (TR-aPTT) activated partial thromboplastin time (60-80s) and (B) compared events of these centers with one center with intermediate range aPTT (40-60s).

RESULTS

After matching, there were no differences in patients' characteristics. In centers aiming at TR-aPTT, major bleeding was numerically lower with aPTT <60s within 48 h of left-Impella™ support, versus patients that achieved the aimed aPTT of ≥60s [aPTT ≥60s: 22 (37.3%) vs. aPTT<60s 14 (23.7%); Hazard ratio [HR], 0.62 (95%) CI, 0.28-1.38; p = 0.234]. Major cardiovascular and cerebrovascular adverse events (MACCE) did not differ between groups. In comparison of centers, TR-aPTT strategy showed higher major bleeding rates [TR: 8 (47.1%) vs. intermediate range: 1 (5.9%); HR, 0.06 (95%) CI, 0.01-0.45; p = 0.006]. MACCE were lower in the intermediate range aPTT group as well [TR 12 (70.6%) vs. intermediate range 5 (29.4%) HR, 0.32 (95%) CI, 0.11-0.92; p = 0.034].

CONCLUSION

This pilot analysis showed that lowering UFH-targets in left-Impella™ supported CS patients seems to be a safe and promising strategy for reducing major bleedings without increasing MACCE. This needs to be validated in larger, randomized clinical trials.

Contemporary approach to cardiogenic shock care: a state-of-the-art review

Cardiogenic shock (CS) is a time-sensitive and hemodynamically complex syndrome with a broad spectrum of etiologies and clinical presentations. Despite contemporary therapies, CS continues to maintain high morbidity and mortality ranging from 35 to 50%. More recently, burgeoning observational research in this field aimed at enhancing the early recognition and characterization of the shock state through standardized team-based protocols, comprehensive hemodynamic profiling, and tailored and selective utilization of temporary mechanical circulatory support devices has been associated with improved outcomes. In this narrative review, we discuss the pathophysiology of CS, novel phenotypes, evolving definitions and staging systems, currently available pharmacologic and device-based therapies, standardized, team-based management protocols, and regionalized systems-of-care aimed at improving shock outcomes. We also explore opportunities for fertile investigation through randomized and non-randomized studies to address the prevailing knowledge gaps that will be critical to improving long-term outcomes.

Cardiac ECMO: changing role in times of Impella and ventricular assist devices?

Mortality in infarct-related as well as heart failure-associated cardiogenic shock remains high, reaching 40-50% depending on the etiology and severity of cardiogenic shock. Percutaneous active mechanical circulatory support devices including veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and microaxial left ventricular mechanical circulatory support devices are rapidly evolving in their use. However, evidence of VA-ECMO therapy has only recently emerged and showed no benefit for mortality, with an associated higher complication rate. Evidence for microaxial left ventricular mechanical circulatory support devices such as the Impella pump (Abiomed, Danvers/MA, USA) is limited. The current article aims to give an overview of the basics of VA-ECMO therapy and microaxial left ventricular mechanical circulatory support devices, the current evidence, ongoing trials, patient selection, and potential complications. This article is freely available.

Microaxial mechanical circulatory support after orthotopic heart transplantation

AIM

Use of microaxial mechanical circulatory support (MCS) has been reported for severe graft rejection or dysfunction after heart transplantation (HTx). We aimed to assess utilization patterns of microaxial MCS after HTx in adolescents (ages 18 and younger) and adults (ages 19 and older).

METHODS

Electronic search was performed to identify all relevant studies on post-HTx use of microaxial support in adults and adolescents. A total of 18 studies were selected and patient-level data were extracted for statistical analysis.

RESULTS

All patients (n=23), including adults (n=15) and adolescents (n=8), underwent Impella (Abiomed, Danvers, MA) microaxial MCS after HTx. Median age was 36 [IQR 18-56] years (Adults, 52 [37-59]; adolescents, 16 [15-17]). Primary right ventricular graft dysfunction was an indication exclusively seen in the adults 40% (6/15), while acute graft rejection was present in 46.7% (7/15) of adults. Median time after transplant was 9 [0-32] months (Adults, 4 [0-32]; adolescents, 11 [4.5, 45]). Duration of Impella support was comparable between adults and adolescents (5 [2.5-8] vs 6 [5-8] days, p = 0.38). Overall improvement was observed both in median LV ejection fraction (23.5% [11.3-28] to 42% [37.8-47.3], p < 0.01) and cardiac index (1.8 [1.2-2.6] to 3 [2.5-3.1], p < 0.01). Retransplantation was required in four adolescents (50%, 4/8). Survival to discharge was achieved by 60.0% (9/15) of adults and 87.5% (7/8) of adolescents respectively (p = 0.37).

CONCLUSION

Indications for microaxial MCS appear to vary between adult and adolescent patients. Overall improvement in LVEF and cardiac index was observed, however, with suboptimal survival to discharge.

The Effect of Mechanical Circulatory Support on Blood Flow in the Ascending Aorta: A Combined Experimental and Computational Study

Percutaneous mechanical circulatory support (MCS) devices are designed for short-term treatment in cases of acute decompensated heart failure as a bridge to transplant or recovery. Some of the known complications of MCS treatments are related to their hemodynamics in the aorta. The current study investigates the effect of MCS on the aortic flow. The study uses combined experimental and numerical methods to delineate complex flow structures. Particle image velocimetry (PIV) is used to capture the vortical and turbulent flow characteristics in a glass model of the human aorta. Computational fluid dynamics (CFD) analyses are used to complete the 3D flow in the aorta. Three specific MCS configurations are examined: a suction pump with a counterclockwise (CCW) rotating impeller, a suction pump with a clockwise (CW) rotating impeller, and a discharge pump with a straight jet. These models were examined under varying flow rates (1-2.5 L/min). The results show that the pump configuration strongly influences the flow in the thoracic aorta. The rotating impeller of the suction pump induces a dominant swirling flow in the aorta. The swirling flow distributes the incoming jet and reduces the turbulent intensity near the aortic valve and in the aorta. In addition, at high flow rates, the local vortices formed near the pump are washed downstream toward the aortic arch. Specifically, an MCS device with a CCW rotating impeller induces a non-physiological CCW helical flow in the descending aorta (which is opposite to the natural helical flow), while CW swirl combines better with the natural helical flow.

Complications in patients with cardiogenic shock on veno-arterial extracorporeal membrane oxygenation therapy: distribution and relevance. Results from an international, multicentre cohort study

AIMS

Veno-arterial extracorporeal membrane oxygenation therapy (VA-ECMO) restores circulation and tissue oxygenation in cardiogenic shock (CS) patients, but can also lead to complications. This study aimed to quantify VA-ECMO complications and analyse their association with overall survival as well as favourable neurological outcome (cerebral performance categories 1 + 2).

METHODS AND RESULTS

All-comer patients with CS treated with VA-ECMO were retrospectively enrolled from 16 centres in four countries (2005-2019). Neurological, bleeding, and ischaemic adverse events (AEs) were considered. From these, typical VA-ECMO complications were identified and analysed separately as device-related complications. n = 501. Overall, 118 were women (24%), median age was 56.0 years, median lactate was 8.1 mmol/L. Acute myocardial infarction caused CS in 289 patients (58%). Thirty-days mortality was 40% (198/501 patients). At least one device-related complication occurred in 252/486 (52%) patients, neurological AEs in 108/469 (23%), bleeding in 192/480 (40%), ischaemic AEs in 123/478 (26%). The 22% of patients with the most AEs accounted for 50% of all AEs. All types of AEs were associated with a worse prognosis. Aside from neurological ones, all AEs and device-related complications were more likely to occur in women; although prediction of AEs outside of neurological AEs was generally poor.

CONCLUSION

Therapy and device-related complications occur in half of all patients treated with VA-ECMO and are associated with a worse prognosis. They accumulate in some patients, especially in women. Aside from neurological events, identification of patients at risk is difficult, highlighting the need to establish additional quantitative markers of complication risk to guide VA-ECMO treatment in CS.

Impella Versus Intra-Aortic Balloon Pump in Patients With Cardiogenic Shock Treated With Venoarterial Extracorporeal Membrane Oxygenation: An Observational Study

BACKGROUND

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used for patients with cardiogenic shock. Although Impella or intra-aortic balloon pump (IABP) is frequently used for left ventricular unloading (LVU) during VA-ECMO treatment, there are limited data on comparative outcomes. We compared outcomes of Impella and IABP for LVU during VA-ECMO.

METHODS AND RESULTS

Using the Nationwide Readmissions Database between 2016 and 2020, we analyzed outcomes in 3 groups of patients with cardiogenic shock requiring VA-ECMO based on LVU strategies: extracorporeal membrane oxygenation (ECMO) only, ECMO with IABP, and ECMO with Impella. Of 15 980 patients on VA-ECMO, IABP and Impella were used in 19.4% and 16.4%, respectively. The proportion of patients receiving Impella significantly increased from 2016 to 2020 (6.5% versus 25.8%; P-trend<0.001). In-hospital mortality was higher with ECMO with Impella (54.8%) compared with ECMO only (50.4%) and ECMO with IABP (48.4%). After adjustment, ECMO with IABP versus ECMO only was associated with lower in-hospital mortality (adjusted odds ratio [aOR], 0.83; P=0.02). ECMO with Impella versus ECMO only had similar in-hospital mortality (aOR, 1.09; P=0.695) but was associated with more bleeding (aOR, 1.21; P=0.007) and more acute kidney injury requiring hemodialysis (aOR, 1.42; P<0.001). ECMO with Impella versus ECMO with IABP was associated with greater risk of acute kidney injury requiring hemodialysis (aOR, 1.49; P=0.002), higher in-hospital mortality (aOR, 1.32; P=0.001), and higher 40-day mortality (hazard ratio, 1.25; P<0.001).

CONCLUSIONS

In patients with cardiogenic shock on VA-ECMO, LVU with Impella, particularly with 2.5/CP, was not associated with improved survival at 40 days but was associated with increased adverse events compared with IABP. More data are needed to assess Impella platform-specific comparative outcomes of LVU.

Clinical characteristics and outcomes of patients requiring prolonged mechanical circulatory support after high-risk percutaneous coronary intervention

BACKGROUND

There are limited data on the clinical characteristics and outcomes of patients who require prolonged mechanical circulatory support (MCS) after Impella-supported high-risk percutaneous coronary intervention (HR-PCI).

AIMS

The aim of this study is to describe the contemporary clinical characteristics, outcomes, and predictors associated with prolonged MCS support after assisted HR-PCI.

METHODS

Patients enrolled in the prospective, multicentre, clinical endpoint-adjudicated PROTECT III study who had undergone HR-PCI using Impella were evaluated. Patient and procedural characteristics and outcomes for those who received prolonged MCS beyond the duration of their index procedure were compared to those in whom MCS was successfully weaned and explanted at the conclusion of the index PCI.

RESULTS

Among 1,155 patients who underwent HR-PCI with Impella between 2017 and 2020 and had sufficient data to confirm the duration of Impella support, 16.5% received prolonged MCS (mean duration 25.2±31.1 hours compared with 1.8±5.8 hours for those who only received intraprocedural MCS). Patients receiving prolonged support presented with more urgent indications (e.g., acute coronary syndromes [ACS], lower ejection fraction [EF], elevated baseline heart rate and lower systolic blood pressure). Use of the Impella CP, intraprocedural complications, periprocedural complications and in-hospital mortality were all more common amongst the prolonged MCS group. Prolonged MCS was associated with increased rates of major adverse cardiovascular and cerebrovascular events, cardiovascular death, and all-cause mortality at 90-day follow-up.

CONCLUSIONS

Patients receiving prolonged MCS after Impella-supported HR-PCI presented with more ACS, reduced EF and less favourable haemodynamics. Additionally, they were more likely to experience intraprocedural and periprocedural complications as well as increased in-hospital and post-discharge mortality.

In-Hospital Mortality in Patients With Cardiogenic Shock Requiring Veno-Arterial Extracorporeal Membrane Oxygenation With Concomitant Use of Impella vs. Intra-Aortic Balloon Pump - A Retrospective Cohort Study Using a Japanese Claims-Based Database

BACKGROUND

Patients with refractory cardiogenic shock (CS) necessitating peripheral veno-arterial extracorporeal membrane oxygenation (VA-ECMO) often require an intra-aortic balloon pump (IABP) or Impella for unloading; however, comparative effectiveness data are currently lacking.Methods and Results: Using Diagnosis Procedure Combination data from approximately 1,200 Japanese acute care hospitals (April 2018-March 2022), we identified 940 patients aged ≥18 years with CS necessitating peripheral VA-ECMO along with IABP (ECMO-IABP; n=801) or Impella (ECPella; n=139) within 48 h of admission. Propensity score matching (126 pairs) indicated comparable in-hospital mortality between the ECPella and ECMO-IABP groups (50.8% vs. 50.0%, respectively; P=1.000). However, the ECPella cohort was on mechanical ventilator support for longer (median [interquartile range] 11.5 [5.0-20.8] vs. 9.0 [4.0-16.8] days; P=0.008) and had a longer hospital stay (median [interquartile range] 32.5 [12.0-59.0] vs. 23.0 [6.3-43.0] days; P=0.017) than the ECMO-IABP cohort. In addition, medical costs were higher for the ECPella than ECMO-IABP group (median [interquartile range] 9.09 [7.20-12.20] vs. 5.23 [3.41-7.00] million Japanese yen; P<0.001).

CONCLUSIONS

Our nationwide study could not demonstrate compelling evidence to support the superior efficacy of Impella over IABP in reducing in-hospital mortality among patients with CS necessitating VA-ECMO. Further investigations are imperative to determine the clinical situations in which the potential effect of Impella can be maximized.

Comparative Healthcare Resource Utilization of Percutaneous Mechanical Circulatory Support Using Impella Versus Intra-aortic Balloon Pump Use for Patients With Acute Coronary Syndrome and Cardiogenic Shock Undergoing Percutaneous Coronary Interventions: Insights From National Inpatient Sample

The use of percutaneous mechanical circulatory support (MCS) devices, including Impella and Intra-aortic balloon pump (IABP), in patients with cardiogenic shock has increased in recent times. We aimed to evaluate the impact of the choice of an MCS device on healthcare resource utilization. We queried the National Inpatient Sample registry between October 2016 and December 2018 to identify adults admitted for acute coronary syndrome-related cardiogenic shock and who received percutaneous coronary intervention (PCI). The study population was segregated into Impella and IABP groups using ICD 10 diagnosis codes. The primary endpoint was high healthcare resource utilization (HRU), while secondary outcomes included periprocedural complications. Propensity scoring matching was used to determine which patients in the Impella cohort had similar health to IABP patients. During the study period, 439,610 patients were admitted who received hemodynamic support using, Impella or IABP on account of acute coronary syndrome complicated by cardiogenic shock (CS). The median age (years) of the Impella cohort and IABP cohorts were similar (64.1 vs 65.1, P = 0.08). Gender distribution of the Impella CS patients was like IABP patients with female majorities in both groups, (71.9% vs 67.9%, P = 0.05). Impella CS patients had a higher representation of those with hypertension (P = 0.002), smoking (P = 0.040), obesity (P = 0.034), diabetes mellitus (P = 0.009), CHF (P = 0.030), COPD (P = 0.034), chronic liver disease (P = 0.028), and chronic kidney disease (P = 0.031). 1:1 Propensity score matching identified 2620 Impella patients' comparable severity index with the IABP patients. Patients with hemodynamic support using Impella had higher healthcare resource utilization, (HRU), the surrogate of length of stay (LOS) ≥7 or nonhome disposition at discharge, when compared with those with IABP (57.41% vs 42.76%, P < 0.0001). Impella CS patients had higher in-hospital mortality as compared to the IABP patients (55.45% vs 45.86%, P < 0.0001). Impella CS patients developed more periprocedural complications, including vascular injury (4.8% vs 1.4%, P < 0.0001), acute kidney injury (58.36% vs 41.64%, P < 0.0001), end-stage renal disease requiring dialysis (8.75% vs 1.25%, P = 0.002) when compared to the IABP patients. Among patients with ACS undergoing PCI and receiving MCS devices, those receiving Impella demonstrated higher healthcare resource utilization, higher LOS ≥7 days, and more nonhome disposition at discharge compared to patients receiving IABP. Further investigation is warranted to elucidate factors associated with these findings.

The spectrum of post-myocardial infarction care: From acute ischemia to heart failure

Heart failure (HF) is the leading cause of mortality in patients with acute myocardial infarction (AMI), with incidence ranging from 14% to 36% in patients admitted due to AMI. HF post-MI develops due to complex inter-play between macrovascular obstruction, microvascular dysfunction, myocardial stunning and remodeling, inflammation, and neuro-hormonal activation. Cardiogenic shock is an extreme presentation of HF post-MI and is associated with a high mortality. Early revascularization is the only therapy shown to improve survival in patients with cardiogenic shock. Treatment of HF post-MI requires prompt recognition and timely introduction of guideline-directed therapies to improve mortality and morbidity. This article aims to provide an up-to-date review on the incidence and pathogenesis of HF post-MI, current strategies to prevent and treat onset of HF post-MI, promising therapeutic strategies, and knowledge gaps in the field.

Utilization of Shock Team and Veno-Arterial Extracorporeal Membrane Oxygenation (VA-ECMO) in the Management of Cardiogenic Shock in Northern Ontario

Background

Despite advancements in critical care and coronary revascularization, cardiogenic shock (CS) outcomes remain poor. Implementing a shock team and use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) have been associated with improved CS outcomes, but its feasibility in remote and rural areas remains unknown.

Methods

This retrospective study included patients with CS who required mechanical circulatory support (MCS) at Health Sciences North, Sudbury, Ontario. The analysis aimed to accomplish 2 objectives: first, to review the outcomes associated with use of Impella (Abiomed, Danvers, MA) and, second, to assess the feasibility of establishing a shock team to facilitate the local implementation of VA-ECMO. The primary endpoint was in-hospital mortality.

Results

The outcomes of 15 patients with CS who received Impella between 2015 and 2021 were reviewed. Their average age was 65 years (standard deviation [SD]: 13), and 8 patients (53%) were female. CS was ischemic in 12 patients (80%). Transfemoral Impella CP (cardiac power) was the most frequently used (93%). Thirteen patients (87%) died during the index hospital stay post-Impella because of progressive circulatory failure. The shock team was established following consultations with several Canadian MCS centres, leading to the development of a protocol to guide use of MCS. There have been 4 cases in which percutaneous VA-ECMO using Cardiohelp (Getinge/Maquet, Wayne, NJ) has been used; 3 (75%) survived beyond the index hospitalization.

Conclusions

This analysis demonstrated the feasibility of implementing a shock team in remote Northern Ontario, enabling the use of VA-ECMO with success in a centre with a sizeable rural catchment area. This initiative helps address the gap in cardiac care outcomes between rural and urban areas in Ontario.

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.

Mechanical circulatory support versus vasopressors alone in patients with acute myocardial infarction and cardiogenic shock undergoing percutaneous coronary intervention

BACKGROUND

Previous studies have compared Impella use to intra-aortic balloon pump (IABP) use in patients with acute myocardial infarction and cardiogenic shock (AMI-CS) undergoing percutaneous coronary intervention (PCI). Our objective was to compare clinical outcomes in patients with AMI-CS undergoing PCI who received Impella (percutaneous left ventricular assist device) without vasopressors, IABP without vasopressors, and vasopressors without mechanical circulatory support (MCS).

METHODS

We queried the National Inpatient Sample (NIS) using ICD-10 codes (2015-2018) to identify patients with AMI-CS undergoing PCI. We created three propensity-matched cohorts to examine clinical outcomes in patients receiving Impella versus IABP, Impella versus vasopressors without MCS, and IABP versus vasopressors without MCS.

RESULTS

Among 17,762 patients, Impella use was associated with significantly higher in-hospital major bleeding (31.4% vs. 13.6%; p < 0.001) and hospital charges (p < 0.001) compared to IABP use, with no benefit in mortality (34.1% vs. 26.9%; p = 0.06). Impella use was associated with significantly higher mortality (42.3% vs. 35.7%; p = 0.02), major bleeding (33.9% vs. 22.7%; p = 0.001), and hospital charges (p < 0.001), when compared to the use of vasopressors without MCS. There were no significant differences in clinical outcomes between IABP use and the use of vasopressor without MCS.

CONCLUSIONS

In this analysis of retrospective data of patients with AMI-CS undergoing PCI, Impella use was associated with higher mortality, major bleeding, and in-hospital charges when compared to vasopressor therapy without MCS. When compared to IABP use, Impella was associated with no mortality benefit, along with higher major bleeding events and in-hospital charges. A vasopressor-only strategy suggested no difference in clinical outcomes when compared to IABP. This study uses the NIS for the first time to highlight outcomes in AMI-CS patients undergoing PCI when treated with vasopressor support without MCS, compared to Impella and IABP use.

Short-term percutaneous mechanical circulatory support: no promise without positioning!

Short-term percutaneous mechanical circulatory support by a micro-axial flow pump is increasingly used to support the left ventricle in cardiogenic shock. After a correct indication and placement, appropriate device management in the cardiac intensive care unit is vital to ensure optimal pump function and adequate haemodynamic support. A key element hereby is a correct percutaneous ventricular assist device (pVAD) position. This review explains how an optimal left-sided pVAD position can be achieved and maintained, focusing on the correct insertion depth and rotational angle. Useful imaging techniques, placement and replacement manoeuvres, and monitoring options through the console are discussed. The frequently encountered problem of mal-rotation towards the mitral valve, which may cause suction alarms, haemolysis, aortic regurgitation, and inadequate haemodynamic support, is explained. Finally, a practical bedside approach to assess pVAD position and discern suction alarms due to mal-positioning from haemodynamic problems is proposed.

Mechanical Support Strategies for High-Risk Procedures in the Invasive Cardiac Catheterization Laboratory: A State-of-the-Art Review

Thanks to advancements in percutaneous cardiac interventions, an expanding patient population now qualifies for treatment through percutaneous endovascular procedures. High-risk interventions far exceed coronary interventions and include transcatheter aortic valve replacement, endovascular management of acute pulmonary embolism and ventricular tachycardia ablation. Given the frequent impairment of ventricular function in these patients, frequently deteriorating during percutaneous interventions, it is hypothesized that mechanical ventricular support may improve periprocedural survival and subsequently patient outcome. In this narrative review, we aimed to provide the relevant evidence found for the clinical use of percutaneous mechanical circulatory support (pMCS). We searched the Pubmed database for articles related to pMCS and to pMCS and invasive cath lab procedures. The articles and their references were evaluated for relevance. We provide an overview of the clinically relevant evidence for intra-aortic balloon pump, Impella, TandemHeart and ECMO and their role as pMCS in high-risk percutaneous coronary intervention, transcatheter valvular procedures, ablations and high-risk pulmonary embolism. We found that the right choice of periprocedural pMCS could provide a solution for the hemodynamic challenges during these procedures. However, to enhance the understanding of the safety and effectiveness of pMCS devices in an often high-risk population, more randomized research is needed.

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.

Postcardiotomy Shock Syndrome: A Narrative Review of Perioperative Diagnosis and Management

Postcardiotomy shock (PCS) is generally described as the inability to separate from cardiopulmonary bypass due to ineffective cardiac output after cardiotomy, which is caused by a primary cardiac disorder, resulting in inadequate tissue perfusion. Postcardiotomy shock occurs in 0.5% to 1.5% of contemporary cardiac surgery cases, and is accompanied by an in-hospital mortality of approximately 67%. In the last 2 decades, the incidence of PCS has increased, likely due to the increased age and baseline morbidity of patients requiring cardiac surgery. In this narrative review, the authors discuss the epidemiology and pathophysiology of PCS, the rationale and evidence behind the initiation, continuation, escalation, and discontinuation of mechanical support devices in PCS, and the anesthetic implications.

Characteristic adverse events with intra-aortic balloon pumps: An analysis of the U.S. Food and Drug Administration MAUDE database from 2016 to 2021

INTRODUCTION

The United States Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE) dataset represents a unique source for post-market surveillance data on adverse events (AE). An analysis of AE with percutaneous mechanical circulatory support (pMCS) devices has previously been reported specifically for microaxial flow pumps. The characteristic AE for the intra-aortic balloon pump (IABP) have not been similarly analyzed or reported.

MATERIAL AND METHODS

All events in the MAUDE dataset between January 1, 2016 and December 31, 2021 were reviewed involving the Linear, Mega and Sensation devices (Datascope/Getinge, Wayne New Jersey). Data was analyzed by two authors and categorized based on AE type, date, event type and device-related or patient-related AE.

RESULTS

A total of 2795 AE were reported over five years. Device malfunction (91.4 %) was the most frequent classification followed by death (5.6 %) and injury (3.0 %). Catheter deformation/fracture/leak accounted for 37.9 % of total AEs. The most common patient event categorization was asymptomatic (90.8 %). Vessel damage/hemorrhage occurred in 1.4 % of reports. Death occurred in 5.6 % of reports and was associated with cardiac arrest in 110 of 156 events. Thrombus formation was described in 1.1 % of AEs. Device optic AE were common and unique to Sensation catheters. Calibration errors were also more common with Sensation (4.6 % versus 1.3 %) compared to other models.

CONCLUSIONS

Publicly reported AE with IABPs are predominantly device malfunctions without clinical sequelae. Injury, vascular damage, bleeding and thrombosis AEs are not frequent amongst reported AEs. Emphasis should be placed on understanding mechanisms of device malfunction in order to improve both reliability and user experience.

Percutaneous ventricular assist device for higher-risk percutaneous coronary intervention in surgically ineligible patients: Indications and outcomes from the OPTIMUM study

BACKGROUND

Indications and outcomes for percutaneous ventricular assist device (pVAD) use in surgically ineligible patients undergoing percutaneous coronary intervention (PCI) remain poorly characterized.

AIMS

We sought to describe the use and timing of pVAD and outcome in surgically ineligible patients.

METHODS

Among 726 patients enrolled in the prospective OPTIMUM study, clinical and health status outcomes were assessed in patients who underwent pVAD-assisted PCI and those without pVAD.

RESULTS

Compared with patients not receiving pVAD (N = 579), those treated with pVAD (N = 142) more likely had heart failure, lower left ventricular ejection fraction (30.7 ± 13.6 vs. 45.9 ± 15.5, p < 0.01), and higher STS 30-day predicted mortality (4.2 [2.1-8.0] vs. 3.3 [1.7-6.6], p = 0.01) and SYNTAX scores (36.1 ± 12.2, vs. 31.5 ± 12.1, p < 0.01). While the pVAD group had higher in-hospital (5.6% vs. 2.2%, p = 0.046), 30-day (9.0% vs. 4.0%, p = 0.01) and 6-month (20.4% vs. 11.7%, p < 0.01) mortality compared to patients without pVAD, this difference appeared to be largely driven by significantly higher mortality among the 20 (14%) patients with unplanned pVAD use (30% in-hospital mortality with unplanned PVAD vs. 1.6% with planned, p < 0.01; 30-day mortality, 38.1% vs. 4.5%, p < 0.01). The degree of 6-month health status improvement among survivors was similar between groups.

CONCLUSION

Surgically ineligible patients with pVAD-assisted PCI had more complex baseline characteristics compared with those without pVAD. Higher mortality in the pVAD group appeared to be driven by very poor outcomes by patients with unplanned, rescue pVAD.

Intracerebral Hematoma in Patients With Impella Ventricular Assist Device Placement for Cardiogenic Shock: Report of Three Cases

Despite the clear benefits of Impella in patients with cardiogenic shock, bleeding is a possible complication. Herein, we report three cases of intracerebral hemorrhage in patients with Impella implantation for cardiogenic shock, which were treated with hematoma evacuation. We present the clinical features, diagnosis, and management (hematoma evacuation) of patients with the Impella device (Abiomed, Danvers, Massachusetts) who developed intracerebral hemorrhage. Case one was a 56-year-old man who presented with chest pain and loss of consciousness, was diagnosed with acute myocardial infarction, and underwent urgent percutaneous coronary intervention and Impella placement. After eight days, the patient developed anisocoria. Computed tomography revealed a left intracerebral hemorrhage. An emergency hematoma evacuation was successfully performed (intraoperative blood loss: 2600 mL). Case two was a 54-year-old male who presented with persistent chest pain and loss of consciousness, was diagnosed with acute myocardial infarction, and underwent an emergency percutaneous coronary intervention with Impella implantation and venoarterial extracorporeal membrane oxygenation. The patient developed intracerebral hemorrhage after 26 days. Hematoma evacuation was successfully performed (intraoperative blood loss: 380 mL). Case three was a 52-year-old male who presented with dyspnea and hypotension, was diagnosed with dilated cardiomyopathy, and underwent Impella implantation and venoarterial extracorporeal membrane oxygenation, followed by which the patient developed subcortical hematoma. An emergency hematoma evacuation was performed (intraoperative blood loss: 3205 mL). The patient died 14 days after admission. Intracerebral hemorrhage is a potential cause of morbidity associated with Impella placement. Although hematoma evacuation is optimal, the bleeding tends to increase.

Percutaneous coronary intervention with Impella support with and without intra-aortic balloon in cardiogenic shock patients

OBJECTIVE

To assess the clinical characteristics and in-hospital bleeding complications and major adverse cardiac and cerebrovascular events (MACCE) associated with the use of Impella alone or the combination of an intra-aortic balloon pump (IABP) with Impella in cardiogenic shock (CS) patients undergoing percutaneous coronary intervention (PCI).

METHODS

All CS patients who underwent PCI and were treated with an Impella mechanical circulatory support (MCS) device were identified. Patients were divided into two groups: having MCS support with Impella alone or with both, IABP and Impella simultaneously (dual MCS group). Bleeding complications were classified by a modified Bleeding Academic Research Consortium (BARC) classification. Major bleeding was defined as BARC≥3 bleeding. MACCE was the composite of in-hospital death, myocardial infarction, cerebrovascular events and major bleeding complications.

RESULTS

Between 2010 and 2018 a total of 101 patients were treated at six tertiary care New York hospitals with either Impella (n = 61) or dual MCS with Impella and IABP (n = 40). Clinical characteristics were similar for both groups. Dual MCS patients presented more often with a STEMI (77.5 % vs. 45.9 %, p = 0.002) and had left main coronary artery intervention (20.3 % vs. 8.6 %, p = 0.03). Major bleeding complications (69.4 % vs. 74.1 %, p = 0.62) and MACCE rates (80.6 % vs. 79.3 %, p = 0.88) were very high but similar in both groups, however access site bleeding complications were lower in patients treated with dual MCS. In-hospital mortality was 29.5 % for the Impella group and 25.0 % for the dual MCS group (p = 062). Access site bleeding complications were lower in in patients treated with dual MCS (5.0 % vs. 24.6 %, p = 0.01).

CONCLUSION

In CS patients undergoing PCI with either the Impella device alone or with Impella and IABP, major bleeding complications and MACCE rates were high but not significantly different between the two groups. In hospital mortality was relatively low in both MCS groups despite the high-risk characteristics of these patients. Future studies should assess the risks and benefits of the simultaneous use of these two MCS in CS patients undergoing PCI.

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.

Contemporary Methods for Predicting Acute Kidney Injury After Coronary Intervention

BACKGROUND

Acute kidney injury (AKI) is the most common complication after percutaneous coronary intervention (PCI). Accurately estimating patients' risks not only creates a means of benchmarking performance but can also be used prospectively to inform practice.

OBJECTIVES

The authors sought to update the 2014 National Cardiovascular Data Registry (NCDR) AKI risk model to provide contemporary estimates of AKI risk after PCI to further improve care.

METHODS

Using the NCDR CathPCI Registry, we identified all 2020 PCIs, excluding those on dialysis or lacking postprocedural creatinine. The cohort was randomly split into a 70% derivation cohort and a 30% validation cohort, and logistic regression models were built to predict AKI (an absolute increase of 0.3 mg/dL in creatinine or a 50% increase from preprocedure baseline) and AKI requiring dialysis. Bedside risk scores were created to facilitate prospective use in clinical care, along with threshold contrast doses to reduce AKI. We tested model calibration and discrimination in the validation cohort.

RESULTS

Among 455,806 PCI procedures, the median age was 67 years (IQR: 58.0-75.0 years), 68.8% were men, and 86.8% were White. The incidence of AKI and new dialysis was 7.2% and 0.7%, respectively. Baseline renal function and variables associated with clinical instability were the strongest predictors of AKI. The final AKI model included 13 variables, with a C-statistic of 0.798 and excellent calibration (intercept = -0.03 and slope = 0.97) in the validation cohort.

CONCLUSIONS

The updated NCDR AKI risk model further refines AKI prediction after PCI, facilitating enhanced clinical care, benchmarking, and quality improvement.

Regurgitation during the fully supported condition of the percutaneous left ventricular assist device

Objective.A percutaneous left ventricular assist device (PLVAD) can be used as a bridge to heart transplantation or as a temporary support for end-stage heart failure. Transvalvularly placed PLVADs may result in aortic regurgitation due to unstable pump position during fully supported operation, which may diminish the pumping effect of forward flow and predispose to complications. Therefore, accurate characterization of aortic regurgitation is essential for proper modeling of heart-pump interactions and validation of control strategies.Approach.In the present study, an improved aortic valve model was used to analyze the severity of regurgitation produced by different pump position offsets. The link between pump position offset degree and regurgitation is validated in the fixed speed mode, and the influence of pump speed on regurgitation is verified in the variable speed mode, using the mock circulatory loop (MCL) experimental platform.Main results.The greater the pump offset and the more severe the regurgitation, the more carefully the pump speed needs to be managed. To avoid over-pumping, the recommended pump speed in this study should not exceed 30 000 rpm.Significance.The modeling approach provide in this study not only makes it easier to comprehend the impact of regurgitation events on the entire interactive system during mechanical assistance, but it also aids in providing timely alerts and suitable management measures.

Review and Key Takeaways of the 2021 Percutaneous Coronary Intervention Guidelines

The 2021 Percutaneous Coronary Intervention guidelines completed by American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions provide a set of guidelines regarding revascularization strategies. With emphasis on equity of care, multidisciplinary heart team use, revascularization for acute coronary syndrome, and stable ischemic heart disease, the guidelines create a thorough framework with recommendations regarding therapeutic strategies. In this comprehensive review, our aim is to summarize the 2021 revascularization guidelines and analyze key points regarding each recommendation.

Trends in Mechanical Circulatory Support Use and Outcomes of Patients With Cardiogenic Shock in Japan, 2010 to 2020 (from a Nationwide Inpatient Database Study)

Little is known about the impact of the downgrade of guideline recommendations for intra-aortic balloon pump (IABP) use and the approval of the Impella in Japan, where IABPs have been predominantly used. This study aimed to describe the annual trends in the mechanical circulatory support (MCS) use and outcomes in patients with cardiogenic shock (CS) requiring MCS. Using the Japanese Diagnosis Procedure Combination database from July 2010 to March 2021, we identified inpatients with CS requiring MCS. The patients were stratified into 3 groups: (1) IABP alone, (2) Impella alone, and (3) extracorporeal membrane oxygenation (ECMO), regardless of IABP or Impella use. The patient characteristics and outcomes were reported by the fiscal year. Of the 160,559 eligible patients, 117,599 (73.2%) used IABP alone, 1,465 (0.9%) Impella alone, and 41,495 (25.8%) ECMO. The prevalence of the use of an IABP alone significantly decreased from 80.5% in 2010 to 65.3% in 2020 (p for trend <0.001), whereas the prevalence of the use of an Impella alone significantly increased from 0.0% to 5.0% and ECMO from 19.5% to 29.6% (p for trend <0.001 for both). In-hospital mortality significantly increased from 29.3% in 2010 to 32.6% in 2020 in the overall patients with CS requiring MCS but significantly decreased in those requiring ECMO from 73.7% to 64.1% (p for trend <0.001 for both). In conclusion, there were significant annual changes in the patterns of MCS use and clinical outcomes in patients with CS requiring MCS.

Impact of Impella protected-percutaneous coronary intervention on left ventricle function recovery of patients with extensive coronary disease and poor left ventricular function

BACKGROUND

The use of Impella support is increasingly adopted to "protect" patients with severe coronary artery disease (CAD) and left ventricle (LV) dysfunction undergoing percutaneous coronary intervention (PCI).

AIMS

To evaluate the impact of Impella-protected (Abiomed, Danvers, Massachusetts, USA) PCIs on myocardial function recovery.

METHODS

Patients with significant LV dysfunction undergoing multi-vessel PCIs with pre-intervention Impella implantation were evaluated by echocardiography before PCI and at median follow up of 6 months: global and segmental LV contractile function were assessed by LV ejection fraction (LVEF) and wall motion score index (WMSI), respectively. Extent of revascularization was graded using the British Cardiovascular Intervention Society Jeopardy score (BCIS-JS). Study endpoints were LVEF and WMSI improvement, and its correlation with revascularization.

RESULTS

A total of 48 high surgical risk (mean EuroSCORE II 8) patients with median LVEF value of 30%, extensive wall motion abnormalities (median WMSI 2.16), and severe multi-vessel CAD (mean SYNTAX score 35) were included. PCIs brought a significant reduction of ischemic myocardium burden with BCIS-JS decrease from mean value of 12 to 4 (p < 0.001). At follow-up, WMSI reduced from 2.2 to 2.0 (p = 0.004) and LVEF increased from 30% to 35% (p = 0.016). WMSI improvement was proportional to the baseline impairment (R - 0.50, p < 0.001), and confined to revascularized segments (from 2.1 to 1.9, p < 0.001).

CONCLUSIONS

In patients with extensive CAD and severe LV dysfunction, multi-vessel Impella-protected PCI was associated to an appreciable contractile recovery, mainly determined by regional wall motion improvement in revascularized segments.

Complications and Outcomes of Impella Treatment in Cardiogenic Shock Patients With and Without Acute Myocardial Infarction

Background In patients with cardiogenic shock (CS), acute myocardial infarction (AMI) is the most common cause, and a percutaneous microaxial ventricular assist device (Impella, Abiomed, Danvers, MA) is a choice for temporary mechanical circulatory support. However, data are limited on complications and outcomes of Impella treatment in patients with CS with and without AMI. Methods and Results Using nationwide prospective registry data in Japan, we included a total of 2047 patients with CS in whom the Impella devices were successfully placed between February 2020 and December 2021. Patients were divided into 2 groups according to the primary indication for the Impella use: AMI versus non-AMI. The primary end point was a composite of in-hospital all-cause death and major complications. Of the 2047 patients, the Impella was indicated for AMI in 1337 (65.3%). In the group without AMI, myocarditis was the leading cause of CS. Patients with AMI-CS were older and more likely to have cardiovascular risk factors than those with non-AMI-CS. The rates of in-hospital mortality (46.0% versus 43.9%, P=0.38) and major complications (35.2% versus 34.7%, P=0.85) were similar between the 2 groups. Overall, multivariable analysis identified older age, higher body mass index, previous transient ischemic attack or stroke, out-of-hospital cardiac arrest, and the Impella 5.0 as factors significantly associated with the primary end point. Conclusions The use of Impella in patients with and without AMI was related to similar clinical outcomes with high mortality and complication rates. Further studies are needed to identify patients who may benefit from the Impella devices in CS. Registration URL: https://www.umin.ac.jp/english. Identifier: UMIN000033603.

Comparative Effectiveness of Percutaneous Microaxial Left Ventricular Assist Device vs Intra-Aortic Balloon Pump or No Mechanical Circulatory Support in Patients With Cardiogenic Shock

IMPORTANCE

Recent studies have produced inconsistent findings regarding the outcomes of the percutaneous microaxial left ventricular assist device (LVAD) during acute myocardial infarction with cardiogenic shock (AMICS).

OBJECTIVE

To compare the percutaneous microaxial LVAD vs alternative treatments among patients presenting with AMICS using observational analyses of administrative data.

DESIGN, SETTING, AND PARTICIPANTS

This comparative effectiveness research study used Medicare fee-for-service claims of patients admitted with AMICS undergoing percutaneous coronary intervention from October 1, 2015, through December 31, 2019. Treatment strategies were compared using (1) inverse probability of treatment weighting to estimate the effect of different baseline treatments in the overall population; (2) instrumental variable analysis to determine the effectiveness of the percutaneous microaxial LVAD among patients whose treatment was influenced by cross-sectional institutional practice patterns; (3) an instrumented difference-in-differences analysis to determine the effectiveness of treatment among patients whose treatment was influenced by longitudinal changes in institutional practice patterns; and (4) a grace period approach to determine the effectiveness of initiating the percutaneous microaxial LVAD within 2 days of percutaneous coronary intervention. Analysis took place between March 2021 and December 2022.

INTERVENTIONS

Percutaneous microaxial LVAD vs alternative treatments (including medical therapy and intra-aortic balloon pump).

MAIN OUTCOMES AND MEASURES

Thirty-day all-cause mortality and readmissions.

RESULTS

Of 23 478 patients, 14 264 (60.8%) were male and the mean (SD) age was 73.9 (9.8) years. In the inverse probability of treatment weighting analysis and grace period approaches, treatment with percutaneous microaxial LVAD was associated with a higher risk-adjusted 30-day mortality (risk difference, 14.9%; 95% CI, 12.9%-17.0%). However, patients receiving the percutaneous microaxial LVAD had a higher frequency of factors associated with severe illness, suggesting possible confounding by measures of illness severity not available in the data. In the instrumental variable analysis, 30-day mortality was also higher with percutaneous microaxial LVAD, but patient and hospital characteristics differed across levels of the instrumental variable, suggesting possible confounding by unmeasured variables (risk difference, 13.5%; 95% CI, 3.9%-23.2%). In the instrumented difference-in-differences analysis, the association between the percutaneous microaxial LVAD and mortality was imprecise, and differences in trends in characteristics between hospitals with different percutaneous microaxial LVAD use suggested potential assumption violations.

CONCLUSIONS

In observational analyses comparing the percutaneous microaxial LVAD to alternative treatments among patients with AMICS, the percutaneous microaxial LVAD was associated with worse outcomes in some analyses, while in other analyses, the association was too imprecise to draw meaningful conclusions. However, the distribution of patient and institutional characteristics between treatment groups or groups defined by institutional differences in treatment use, including changes in use over time, combined with clinical knowledge of illness severity factors not captured in the data, suggested violations of key assumptions that are needed for valid causal inference with different observational analyses. Randomized clinical trials of mechanical support devices will allow valid comparisons across candidate treatment strategies and help resolve ongoing controversies.

Management of Bleeding and Hemolysis During Percutaneous Microaxial Flow Pump Support: A Practical Approach

Percutaneous ventricular assist devices (pVADs) are increasingly being used because of improved experience and availability. The Impella (Abiomed), a percutaneous microaxial, continuous-flow, short-term ventricular assist device, requires meticulous postimplantation management to avoid the 2 most frequent complications, namely, bleeding and hemolysis. A standardized approach to the prevention, detection, and treatment of these complications is mandatory to improve outcomes. The risk for hemolysis is mostly influenced by pump instability, resulting from patient- or device-related factors. Upfront echocardiographic assessment, frequent monitoring, and prompt intervention are essential. The precarious hemostatic balance during pVAD support results from the combination of a procoagulant state, due to critical illness and contact pathway activation, together with a variety of factors aggravating bleeding risk. Preventive strategies and appropriate management, adapted to the impact of the bleeding, are crucial. This review offers a guide to physicians to tackle these device-related complications in this critically ill pVAD-supported patient population.