Left ventricular unloading and concomitant total cardiac output increase by the use of percutaneous impella recover LP 2.5 assist device during high-risk coronary intervention

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.

Trajectories of Cardiac Function Following Treatment With an Impella Device in Patients With Acute Anterior ST-Elevation Myocardial Infarction

Background

Left ventricular (LV) unloading via the percutaneous micro-axial Impella pump is increasingly used in patients with anterior ST-segment elevation myocardial infarction (STEMI) and overt cardiogenic shock. In this context, the evolution of cardiac function and dimensions beyond hospital discharge remains uncertain. We aimed to characterize echocardiographic changes over time in patients with acute anterior STEMI treated with an Impella device.

Methods

From an ongoing prospective registry, consecutive patients with acute anterior STEMI managed with an Impella device were extracted. Transthoracic echocardiography was performed at index hospitalization and at first outpatient follow-up. Predictors of response, defined as a ≥ 10% absolute increase in left ventricular ejection fraction (LVEF) at follow-up, were sought.

Results

A total of 66 patients (89.4% male, aged 64.3 ± 11.6 years) with anterior STEMI were treated with an Impella device in the first 24 hours of hospitalization, from 2014 to 2022. In-hospital mortality was 24%. Major bleeding and vascular complications requiring surgery occurred in 24% and 11% of patients, respectively. At baseline, mean LVEF was 34% ±12%. At follow-up, survivors showed a significant increase in LVEF (P < 0.0001), whereas LV dimensions, diastolic parameters, and measures of right ventricular dimension and function remained stable. Overall, 28 patients had a ≥ 10% absolute increase in LVEF at follow-up. Baseline creatinine was the only significant predictor of response at univariate analysis.

Conclusions

Among patients with anterior STEMI requiring mechanical hemodynamic support with an Impella device, the majority of survivors showed a sustained increase in LV function, without evidence of adverse remodelling. This signal warrants further investigation in dedicated trials.

Predictive value of the APACHE II score in cardiogenic shock patients treated with a percutaneous left ventricular assist device

Background

The APACHE II score assesses patient prognosis in intensive care units. Different disease entities are predictable by using a specific factor called Diagnostic Category Weight (DCW). We aimed to validate the prognostic value of the APACHE II score in patients treated with a percutaneous left ventricular assist device because of refractory cardiogenic shock (CS).

Methods

From the Dresden Impella Registry, we analyzed 180 patients receiving an Impella CP®. The main outcome was the observed intrahospital mortality (S ^ ( t h o s p ) ), which was compared to the predicted mortality estimated by the APACHE II score.

Results

The APACHE II score, which was 33.5 ± 0.6, significantly overestimated intrahospital mortality (S ^ ( t h o s p ) 54.4 ± 3.7% vs. APACHE II 74.6 ± 1.6%; p < 0.001). Nevertheless, the APACHE II score showed an acceptable accuracy to predict intrahospital mortality (ROC AUC 0.70; 95% CI 0.62-0.78). Thus, we adapted the formula for calculation of predicted mortality by adjusting DCW. The total registry cohort was randomly divided into derivation group for calculation of adjusted DCW and validation group for testing. Intrahospital mortality was much more precisely predicted using the adjusted DCW compared to the conventional DCW (difference of predicted and observed mortality: -4.7 ± 2.4% vs. -23.2 ± 2.3%; p < 0.001). The new calculated DCW was -1.183 for the total cohort.

Conclusion

The APACHE II score has an acceptable accuracy for the prediction of intrahospital mortality but overestimates its total amount in CS patients. Adjustment of the DCW can lead to a much more precise prediction of prognosis.

Ventricular Unloading Using the ImpellaTM Device in Cardiogenic Shock

Cardiogenic shock (CS) remains a leading cause of hospital death. However, the use of mechanical circulatory support has fundamentally changed CS management over the last decade and is rapidly increasing. In contrast to extracorporeal membrane oxygenation as well as counterpulsation with an intraaortic balloon pump, ventricular unloading by the Impella™ device actively reduces ventricular volume as well as pressure and augments systemic blood flow at the same time. By improving myocardial oxygen supply and enhancing systemic circulation, the Impella device potentially protects myocardium, facilitates ventricular recovery and may interrupt the shock spiral. So far, the evidence supporting the use of Impella™ in CS patients derives mostly from observational studies, and there is a need for adequate randomized trials. However, the Impella™ device appears a promising technology for management of CS patients. But a profound understanding of the device, its physiologic impact and clinical application are all important when evaluating CS patients for percutaneous circulatory support. This review provides a comprehensive overview of the percutaneous assist device Impella™. Moreover, it highlights in depth the rationale for ventricular unloading in CS and describes practical aspects to optimize care for patients requiring hemodynamic support.

Impella in Transport: Physiology, Mechanics, Complications, and Transport Considerations

Cardiogenic shock (CS) represents a spectrum of hemodynamic deficits in which the cardiac output is insufficient to provide adequate tissue perfusion. The Impella (Abiomed Inc, Danvers, MA) device, a contemporary percutaneous ventricular support, is most often indicated for classic, deteriorating, and extremis Society for Coronary Angiography and Intervention stages of CS, which describe CS that is not responsive to optimal medical management and conventional treatment measures. Impella devices are an evolving field of mechanical support that is used with increasing frequency. Critical care transport medicine crews are required to transport patient support by the Impella device with increasing frequency. It is important that critical care transport medicine crews are familiar with the Impella device and are able to troubleshoot complications that may arise in the transport environment. This article reviews many aspects of the Impella device critical to the transport of this complex patient population.

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.

Percutaneous Left Ventricular Assist Device Leads to Heart Rhythm Stabilisation in Cardiogenic Shock: Results from the Dresden Impella Registry

BACKGROUND

Severe heart rhythm disturbances (SHRDs) occur regularly in cardiogenic shock (CS). Percutaneous left ventricular assist devices (pLVADs) can actively unload the left ventricle (LV), decreasing left ventricular end-diastolic pressure and wall tension, which are suspected parameters for the induction and maintenance of arrhythmias. The aim of this study was to describe effects of LV unloading on SHRD.

METHOD

In the Dresden Impella Registry, 97 patients received an Impella CP in refractory CS. Of them, 19 had SHRDs, which were not stopped by common therapeutic strategies such as electrical defibrillation or antiarrhythmic drugs. They were only stopped after implantation of a micro-axial heart pump. This phenomenon was referred to as heart rhythm stabilisation (HRS). Clinical outcome and laboratory parameters were assessed and risk factors for the occurrence of HRS were identified.

RESULTS

All 19 patients with refractory SHRD terminated immediately into a stable heart rhythm after insertion of the micro-axial heart pump. In 37% no additional defibrillation was needed. Of the patients with HRS, CS was mostly caused by myocardial infarction (68%). Resuscitation before pLVAD was performed in 89% for more than 30 minutes. Patients with HRS were resuscitated more frequently and for a longer duration than patients without HRS. After HRS, the serum lactate and norepinephrine dosage decreased in the first 12 hours, whereas left ventricular ejection fraction increased by 95%.

CONCLUSIONS

Left ventricular unloading in patients with CS seems to be an option for treating patients with sustained life-threatening tachycardia, who are refractory to common treatment.

Use of a Virtual Mock Loop model to evaluate a new left ventricular assist device for transapical insertion

We are developing a novel type of miniaturized left ventricular assist device that is configured for transapical insertion. The aim of this study was to assess the performance and function of a new pump by using a Virtual Mock Loop system for device characterization and mapping. The results, such as pressure-flow performance curves, from pump testing in a physical mock circulatory loop were used to analyze its function as a left ventricular assist device. The Virtual Mock Loop system was programmed to mimic the normal heart condition, systolic heart failure, diastolic heart failure, and both systolic and diastolic heart failure, and to provide hemodynamic pressure values before and after the activation of several left ventricular assist device pump speeds (12,000, 14,000, and 16,000 r/min). With pump support, systemic flow and mean aortic pressure increased, and mean left atrial pressure and pulmonary artery pressure decreased for all heart conditions. Regarding high pump-speed support, the systemic flow, aortic pressure, left atrial pressure, and pulmonary artery pressure returned to the level of the normal heart condition. Based on the test results from the Virtual Mock Loop system, the new left ventricular assist device for transapical insertion may be able to ease the symptoms of patients with various types of heart failure. The Virtual Mock Loop system could be helpful to assess pump performance before in vitro bench testing.

When the Complex Meets the High-Risk: Mechanical Cardiac Support Devices and Percutaneous Coronary Interventions in Severe Coronary Artery Disease

Coronary artery disease (CAD) remains a leading cause of mortality and morbidity worldwide. Few practice guidelines directly address the issue of revascularization in patients with CAD at higher risk of periprocedural complications. It remains a challenge to appropriately identify the subset of patients with CAD who will require short-term use of mechanical cardiocirculatory support devices (MCSDs) when high-risk (HR) percutaneous coronary intervention (PCI) is required. Issues of the complexity (coronary anatomy and high burden of comorbidities) and risk status (hemodynamic precarity or compromise) need to be considered when considering revascularization in patients. This review will focus on the evolving concept of protected PCI in patients with CAD, and how a balanced, integrated heart-team approach remains the path to optimal patient-centred care in the setting of HR-PCI supported with MCSD.

Impact of Hemodynamic Support on Outcome in Patients Undergoing High-Risk Percutaneous Coronary Intervention

The use of left-ventricular (LV) hemodynamic support might facilitate high-risk percutaneous coronary interventions (PCI) in patients with complex coronary artery disease. The impact on outcome is a matter of ongoing debate. We assessed the outcome of high-risk patients who underwent protected PCI in comparison to patients who underwent unprotected high-risk PCI. One hundred and thirty nine patients underwent nonemergent high-risk PCI; 24 (17%) patients underwent protected PCI. To address selection bias, we performed a propensity score matched subanalysis. The primary end point was the occurrence of a major adverse cardiac event during the first year. Patients with protected PCI had a higher logistic EuroSCORE (logES) (protected PCI: 19% vs unprotected PCI: 12%; p = 0.01), a higher SYNTAX score (45 vs 36, p = 0.07), and significantly more often reduced LV function (40% vs 55%; p < 0.001). In protected PCI patients, complete revascularization was more often achieved (87% vs 58%, p = 0.007) without the occurrence of death at 30 days of follow-up (0% vs 4%, p = 0.31). After propensity score matching, patients who underwent protected PCI had a similar 1-year major adverse cardiac event rate compared with patients who underwent unprotected PCI (21% vs 17%, p = 0.67), despite significantly higher procedural complexity for example, more often complex left main bifurcation lesions (71% vs 29%; p = 0.004). In conclusion, 1-year outcome of patients who underwent protected PCI was not different from that in patients with less complex procedures without hemodynamic support, despite more complex coronary anatomy, a higher comorbidity burden, and more often reduced LV function.

Mechanical Circulatory Support in the Cardiac Catheterization Laboratory for Cardiogenic Shock

Despite the development of acute revascularisation, the mortality rate for cardiogenic shock remains around 50%. Mechanical circulatory support devices have long held promise in improving outcomes in shock, but high-quality evidence of benefit has not been forthcoming. In this article we review the currently available devices for treating shock, their physiological effects and the evidence base for their use in practice. We subsequently look ahead within this developing field, including new devices and novel indications for established technology.

Peripartum Cardiomyopathy: Current Options for Treatment and Cardiovascular Support

Peripartum cardiomyopathy is a rare form of acute heart failure but the major cause of all deaths in pregnant patients with heart failure. Improved survival rates in recent years, however, emphasize the importance of early recognition and initiation of heart failure treatment. This article, therefore, attempts to raise awareness among cardiac and obstetric anesthesiologists as well as intensivists of this often fatal diagnosis. This review summarizes theories of the pathophysiology and outcome of peripartum cardiomyopathy. Based on the most recent literature, it further outlines diagnostic criteria and treatment options including medical management, mechanical circulatory support devices, and heart transplantation. Earlier recognition of this rare condition and a new generation of mechanical circulatory devices has contributed to the improved outcome. More frequently, patients in cardiogenic shock who fail medical management are successfully bridged to recovery on extracorporeal circulatory devices or survive with a long-lasting implantable ventricular assist device. The outcome of transplanted patients with peripartum cardiomyopathy, however, is worse compared to other recipients of heart transplants and warrants further investigation in the future.

Unprotected versus protected high-risk percutaneous coronary intervention with the Impella 2.5 in patients with multivessel disease and severely reduced left ventricular function

Selecting a revascularization strategy in patients with multivessel disease (MVD) and severely reduced left ventricular ejection fraction (LVEF) remains a challenge. PCI with Impella 2.5 may facilitate high-risk PCI, however long-term results comparing unprotected versus protected PCI are currently unknown. We sought to evaluate the outcome of patients undergoing protected compared to unprotected percutaneous coronary intervention (PCI) in the setting of MVD and severely reduced LVEF.We included patients with MVD and severely reduced LVEF (≤35%) in this retrospective, single-centre study. Patients that underwent unprotected PCI before the start of a dedicated protected PCI program with Impella 2.5 were compared to patients that were treated with protected PCI after the start of the program. The primary endpoint was defined as major adverse cardiac and cerebrovascular events (MACCE) during a 1-year follow-up. The secondary endpoints consisted of in-hospital MACCE and adverse events.A total of 61 patients (mean age 70.7 ± 10.9 years, 83.6% male) were included in our study, of which 28 (45.9%) underwent protected PCI. The primary endpoint was reached by 26.7% and did not differ between groups (P = .90). In-hospital MACCE (P = 1.00) and in-hospital adverse events (P = .12) also demonstrated no significant differences. Multivariate logistic regression identified procedural success defined as complete revascularization and absence of in-hospital major clinical complications as protective parameter for MACCE (OR 0.17, 95% CI 0.04-0.70, P = .02).Patients with MVD and severely depressed LVEF undergoing protected PCI with Impella 2.5 demonstrate similar in-hospital and one-year outcomes compared to unprotected PCI.

The effectiveness and safety of the Impella ventricular assist device for high-risk percutaneous coronary interventions: A systematic review

BACKGROUND

Small randomized controlled trials (RCTs) and observational studies have examined the effectiveness and safety of the Impella device, a percutaneous left ventricular assist device, in the setting of high-risk percutaneous coronary intervention (PCI). However, data are sparse and results are conflicting. Our objective was to evaluate the effectiveness and safety of the Impella device in high-risk patients undergoing PCI via a systematic review of the literature.

METHODS

We searched Medline, EMBASE, and the Cochrane Library for RCTs and observational studies that evaluated the Impella device in high-risk patients undergoing PCI. Inclusion was restricted to studies in which ≥10 patients received the Impella device; both uncontrolled and controlled (versus intra-aortic-balloon pump [IABP]) studies were included.

RESULTS

A total of 20 studies (4 RCTs, 2 controlled observational studies, and 14 uncontrolled observational studies; 1,287 patients) were included, with follow-up ranging from 1 to 42 months. The use of Impella resulted in improved procedural and hemodynamic characteristics in controlled and uncontrolled studies. In controlled studies, the 30-day rates of all-cause mortality and MACE were similar across groups. In most uncontrolled studies, the 30-day rates of all-cause mortality were generally low (range: 3.7%-10%), though rates of MACE were slightly higher (range: 5%-20%).

CONCLUSION

The Impella device was found to improve procedural and hemodynamic parameters, but only limited randomized data are available regarding clinical outcomes associated with its use. Large, multicenter RCTs are needed to definitively establish the effectiveness of the Impella device among high-risk PCI patients.

Hemodynamic Support With a Microaxial Percutaneous Left Ventricular Assist Device (Impella) Protects Against Acute Kidney Injury in Patients Undergoing High-Risk Percutaneous Coronary Intervention

Rationale:

Acute kidney injury (AKI) is common during high-risk percutaneous coronary intervention (PCI), particularly in those with severely reduced left ventricular ejection fraction. The impact of partial hemodynamic support with a microaxial percutaneous left ventricular assist device (pLVAD) on renal function after high-risk PCI remains unknown.

Objective:

We tested the hypothesis that partial hemodynamic support with the Impella 2.5 microaxial pLVAD during high-risk PCI protected against AKI.

Methods and Results:

In this retrospective, single-center study, we analyzed data from 230 patients (115 consecutive pLVAD-supported and 115 unsupported matched-controls) undergoing high-risk PCI with ejection fraction ≤35%. The primary outcome was incidence of in-hospital AKI according to AKI network criteria. Logistic regression analysis determined the predictors of AKI. Overall, 5.2% (6) of pLVAD-supported patients versus 27.8% (32) of unsupported control patients developed AKI ( P <0.001). Similarly, 0.9% (1) versus 6.1% (7) required postprocedural hemodialysis ( P <0.05). Microaxial pLVAD support during high-risk PCI was independently associated with a significant reduction in AKI (adjusted odds ratio, 0.13; 95% confidence intervals, 0.09–0.31; P <0.001). Despite preexisting CKD or a lower ejection fraction, pLVAD support protection against AKI persisted (adjusted odds ratio, 0.63; 95% confidence intervals, 0.25–0.83; P =0.04 and adjusted odds ratio, 0.16; 95% confidence intervals, 0.12–0.28; P <0.001, respectively).

Conclusions:

Impella 2.5 (pLVAD) support protected against AKI during high-risk PCI. This renal protective effect persisted despite the presence of underlying CKD and decreasing ejection fraction.

Surgical implant techniques of left ventricular assist devices: an overview of acute and durable devices

Left ventricular support for the failing heart has evolved to include short-term and long-term devices. These devices are implanted percutaneously and surgically. This manuscript provides a general overview of the contemporary, typically practiced, implant techniques with additional insight on minimally invasive approaches.

Use of left ventricular support devices during acute coronary syndrome and percutaneous coronary intervention

In an effort to improve outcomes in percutaneous coronary intervention (PCI), percutaneous ventricular assist devices (PVADs) have been investigated in (1) high-risk PCI, (2) acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) and (3) in AMI without CS. PCI has become an increasing complex due to an ageing population with complex disease and the frequent presence of impaired LV function. Patients undergoing high-risk PCI in these circumstances are prone to acute cardiovascular collapse. Additionally, mortality in AMI complicated by CS remains high. Lastly, LV support during AMI may reduce infarct size and therefore preserve LV function. At present, four commercially available devices exist: intra-aortic balloon pump counterpulsation (IABP), Impella, TandemHeart and extracorporeal membrane oxygenation (ECMO). These devices are employed in an effort to increase cardiac output, mean arterial pressure (MAP) and coronary perfusion and to reduce pulmonary capillary wedge pressure (PCWP). The mechanism of action differs with each device, and there are advantages and disadvantages. In this update, we discuss recent data describing the use of PVADs to support patients with AMI with or without cardiogenic shock and during high-risk PCI. We focus on the unique features of each device, highlighting strengths, weaknesses and frequently encountered complications, which may be important when tailoring the most appropriate PVAD therapy to an individual patient's need.

Mechanical circulatory support with impella to facilitate percutaneous coronary intervention for post-TAVI bilateral coronary obstruction

One of the potential complications of transcatheter aortic valve implantation (TAVI) is coronary obstruction (CO), which can occur by displacement of heavily calcified native valve cusps against the coronary ostium. Treatment mandates immediate percutaneous coronary intervention (PCI) to restore coronary flow and improve hemodynamics and if unsuccessful, urgent implementation of circulatory support, commonly extracorporeal, with subsequent surgical revascularization. We report a case of post-TAVI CO for which successful emergent deployment of Impella percutaneous mechanical circulatory support to restore hemodynamic stability facilitated definitive treatment with bilateral PCI. Impella support represents an expeditious, effective, and widely available therapy to complement and facilitate PCI in the treatment of CO complicating TAVI, and may diminish requirement for urgent coronary artery bypass surgery. © 2015 Wiley Periodicals, Inc.

Percutaneous Mechanical Support in Cardiogenic Shock: A Review

Cardiogenic shock (CS) is a life-threatening condition associated with significant morbidity and mortality. Pharmacological therapy is often the first line of treatment but mechanical support can provide substantial hemodynamic improvement in refractory CS. Percutaneous mechanical support devices are placed in a minimally invasive manner and provide life-saving assistance to the failing myocardium. We review the percutaneous devices currently available, the evidence behind their use, and the new advances in percutaneous technology being evaluated for the treatment of CS.

Percutaneous Mechanical Ventricular Support in Acute Cardiac Care: A UK Quaternary Centre Experience Using 2.5L, 3.8L and 5.0L Impella Catheters

Aims

The Impella is a percutaneous ventricular assist device. The majority of published data describes the 2.5L and 5.0L devices, and little data is available for the newer 3.8L device. We examined the indications and outcomes from our single-centre “real-world” registry at The Queen Elizabeth Hospital, Birmingham, UK, using all three pump sizes.

Methods and Results

Records from all patients who underwent attempted Impella-assisted procedures at our centre were examined retrospectively. Impella implantation was attempted in 49 patients (mean age 72 ± 13 years; 80% male) and was successful in 48 (98%). 45 patients underwent high-risk percutaneous coronary intervention (PCI), one patient underwent balloon aortic valvuloplasty and 3 patients had Impella as a bridge to cardiac transplantation. The 2.5L and 3.8L devices were used in 36 (75%) and 11 (23%) patients, respectively, while one patient (2%) had the 5L device. Vascular complications occurred in only one patient (2%) and stroke and peri-procedural myocardial infarction occurred in one patient (2%), while in-hospital mortality was 20% (10/49).

Conclusions

In this large real-world registry, we have demonstrated the safety and feasibility of the Impella device for a wide range of indications. This includes the first series of the 3.8L device which provides superior support with no increase in vascular complications.

Electronic supplementary material

The online version of this article (doi:10.1007/s40119-014-0033-8) contains supplementary material, which is available to authorized users.

Full neurologic recovery and return of spontaneous circulation following prolonged cardiac arrest facilitated by percutaneous left ventricular assist device

Sudden cardiac arrest is associated with high early mortality, which is largely related to postcardiac arrest syndrome characterized by an acute but often transient decrease in left ventricular (LV) function. The stunned LV provides poor cardiac output, which compounds the initial global insult from hypoperfusion. If employed early, an LV assist device (LVAD) may improve survival and neurologic outcome; however, traditional methods of augmenting LV function have significant drawbacks, limiting their usefulness in the periarrest period. Full cardiac support with cardiopulmonary bypass is not always readily available but is increasingly being studied as a tool to intensify resuscitation. There have been no controlled trials studying the early use of percutaneous LVADs (pLVADs) in pericardiac arrest patients or intra-arrest as a bridge to return of spontaneous circulation. This article presents a case study and discussion of a patient who arrested while undergoing an elective coronary angioplasty and suffered prolonged cardiopulmonary resuscitation. During resuscitation, treatment included placement of a pLVAD and initiation of therapeutic hypothermia. The patient made a rapid and full recovery.

Evaluating the learning curve in the prospective Randomized Clinical Trial of hemodynamic support with Impella 2.5 versus Intra-Aortic Balloon Pump in patients undergoing high-risk percutaneous coronary intervention: a prespecified subanalysis of the PROTECT II study

BACKGROUND

The introduction of new medical devices may be accompanied by a learning curve.

METHODS

To evaluate the impact of the device learning curve on the outcomes of PROTECT II trial, comparing Impella 2.5 versus the intra-aortic balloon pump (IABP) during high-risk percutaneous coronary intervention, we report on a prespecified analysis, excluding the first Impella 2.5 and IABP patients at each site.

RESULTS

A total of 448 patients were enrolled at 74 sites. Among these, 58 patients were the first to receive Impella 2.5 at their site, 62 were the first to receive IABP. A trend toward higher major adverse events (MAEs) at 30 days was observed for the subgroup of first versus remaining Impella 2.5 patients: 44.8% versus 31.7%, P = .072. MAE rates for the first and remaining IABP patients were similar at 30 days. After exclusion of the first patient in each group, MAE rates for Impella 2.5 and IABP were 31.7% versus 40.0% (P = .119) at 30 days and 38.0% versus 50.0% (P = .029) at 90 days.

CONCLUSIONS

Significantly lower 90-day MAE rates were observed with the use of Impella 2.5 compared to the use of IABP after excluding the first patient per group at each site. This prespecified analysis suggests a learning curve associated with initial introduction of the Impella 2.5. Clinical trials should better address the training aspect of new devices, especially when compared with more established devices.

Economic and Operational Implications of a Standardized Approach to Hemodynamic Support Therapy Using Percutaneous Cardiac Assist Devices

Objective

Impella 2.5 has been shown to reduce major adverse events for patients undergoing elective high-risk percutaneous coronary intervention. We performed a single-center retrospective study to compare the costs and resource use of Impella 2.5 and intra-aortic balloon pump (IABP) support.

Methods

All high-risk patients who received Impella 2.5 (n = 35) and IABP (n = 295) support from December 2008 to July 2011 were included. Propensity score matching identified a balanced 1:1 matched cohort (35 Impella vs 35 IABP) based on indications for implantation, preimplantation hemodynamics, and age. Diagnostic, procedural, financial, and resource use data were collected.

Results

As compared with IABP, Impella offered a more predictable course of treatment/resource consumption and was not associated with any extreme cost outliers (17.1% vs 0.0%, respectively; P = 0.025). The mean admission and 90-day episode of care total costs for Impella were 5.5% ($67,681 vs $71,608, P = 0.79) and 4.2% ($70,680 vs $73,476, P = 0.85) lesser than that for IABP, respectively. Although not statistically significant, Impella patients had a trend toward lower rehospitalization rates (11.4% vs 20%), lesser mean index length of hospital stay (11.2 vs 13.7), and 90-day (11.7 vs 14.2) episode of care length of hospital stay.

Conclusions

Impella support was associated with consistent course of treatment/resource consumption with significantly fewer 90-day extreme cost outliers than was IABP. The lower index and 90-day follow-up cost trends observed for Impella were driven by shorter length of hospital stay and fewer rehospitalizations. As providers strive to improve quality of care by reducing variability, these findings have implications for the development of hemodynamic support algorithms.

Percutaneous Assist Devices for Infarct Size Reduction

Improving myocyte salvage during acute myocardial infarction (AMI) has proved elusive; the keys to success seem to be the ability to lower oxygen demand of ischemic myocardium and also activate salvage enzyme pathways to take advantage of endogenous cardioprotective mechanisms. Pharmacologic approaches have been largely unsuccessful. A percutaneous left ventricular (LV) assist device could improve myocyte salvage during AMI therapy if it were able to reduce myocardial oxygen demand, wall tension, and LV stroke work substantially.

Percutaneous Assist Device for Cardiopulmonary Resuscitation

Persistent cardiac arrest is often caused by coronary ischemia. Urgent revascularization during on-going resuscitation with the support of percutaneous left ventricular assist devices (PVAD) may be feasible and can have the potential to improve the prognosis. Transport during resuscitation is a challenge that may be overcome with the use of cardiopulmonary resuscitation devices. In the catheterization laboratory, rapid deployment of PVAD may reduce ischemia, contribute to electrical stabilization of the heart, and facilitate definite treatment with percutaneous coronary intervention. After revascularization, PVAD therapy may promote myocardial recovery and improve vital organ perfusion in a critical phase.

Comparison of Impella and intra-aortic balloon pump in high-risk percutaneous coronary intervention: vascular complications and incidence of bleeding

OBJECTIVE

Compare vascular complications and incidence of bleeding of Impella 2.5 and intra-aortic balloon pump (IABP) in high-risk percutaneous coronary interventions (PCI).

BACKGROUND

Large arterial sheath size for device insertion is associated with vascular and/or bleeding complications; gastrointestinal bleeding may also occur with anti-coagulation use.

METHODS

Patients with an acute coronary syndrome receiving Impella 2.5 or IABP during high-risk PCI were studied (13 Impella; 62 IABP). Vascular complications and incidence of bleeding were compared.

RESULTS

Post-procedure hematocrit was similar between groups. Blood transfusion occurred in 38.4% and 32.2% of patients in the Impella and IABP groups, respectively (P = NS); 65.3%, 30.7% and 3.8% of bleeding were due to vascular access site/procedure related, gastrointestinal and genitourinary, respectively. There was no statistical significant difference in vascular complications between the Impella and IABP groups (15.3% and 6.4% of patients, respectively); mesenteric ischemia (n = 1) and aortic rupture (n = 1) were only in the IABP group. In-hospital and one-year mortality were not statistically significant between groups.

CONCLUSION

Impella can be used as safely as IABP during high-risk PCI with similar vascular and bleeding complications. Importantly, approximately one third of bleeding was from the gastrointestinal system warranting careful prophylactic measures and monitoring.

The Impella Recover 2.5 and TandemHeart ventricular assist devices are safe and associated with equivalent clinical outcomes in patients undergoing high-risk percutaneous coronary intervention

OBJECTIVES

To compare the practical use, safety, and clinical outcomes associated with the TandemHeart (TH) versus Impella Recover 2.5 (IR2.5) devices when used for circulatory support during high-risk percutaneous coronary intervention (PCI).

BACKGROUND

Small studies and registries suggest safety and efficacy for the TH and IR2.5 percutaneous-left ventricular assist devices (P-LVADs). However, these P-LVADs differ markedly in their insertion, operation, and manner of circulatory augmentation. To date, no study has compared these devices.

METHODS

We identified 68 patients (49 males, 19 females; age 71.1 ± 12.1 years) from our single-center database that underwent "high-risk" PCI with P-LVAD support from April 2005 to June 2010 (32 with TH, 36 with IR2.5). Relevant data were extracted for analysis.

RESULTS

Baseline demographics were similar, including low LVEF (overall mean 31.0 ± 13.7%) and elevated STS mortality risk score (4.2 ± 3.7%). Angiographic characteristics were also similar, with a mean of 2.4 ± 1.0 lesions treated per patient, and 29% undergoing left main PCI. PCI success rates were 99% in both groups, with similar in-hospital outcomes and a combined 7% major vascular access site complication rate. A single episode of left atrial perforation occurred during TH use. No patient required emergent CABG and no in-hospital deaths occurred. The 30-day MACE rate (death, myocardial infarction, target lesion revascularization) was 5.8%. There were no differences between the IR2.5 and TH groups with respect to short- or long-term clinical outcomes.

CONCLUSIONS

The IR2.5 and TH assist devices are safe, equally effective, and associated with acceptable short- and long-term clinical outcomes in patients undergoing "high-risk" PCI.

Impella 2.5 in a patient with left main coronary artery occlusion

Short-term assist devices have been indicated in many clinical settings mostly as a bridge to the next step. In this article, we report a case of cardiogenic shock due to acute occlusion of left main coronary artery who was scheduled to be transferred from Iran to Germany for the next treatment (permanent assist device implantation). Impella 2.5 (Abiomed Inc., Danvers, MA, USA), a short-term assist device, made the long distance journey possible. <Learning objective: Managing of severe cardiogenic shock by early revascularization and prompt installation of mechanical circulatory support in peripheral hospital as bridge to decision and successful long-distance transfer on mechanical circulatory support.>.

Percutaneous left ventricular assistance in post cardiac arrest shock: comparison of intra aortic blood pump and IMPELLA Recover LP2.5

AIM

To compare the feasibility, safety and outcome of IMPELLA Recover LP2.5 cardiac assistance and intra aortic balloon pump (IABP) in patients with post-cardiac arrest shock.

BACKGROUND

The high early mortality rate of post-cardiac arrest patients is attributed to a "post cardiac arrest syndrome" characterized by an acute and transient left ventricular (LV) systolic dysfunction. LV assistance with IMPELLA Recover LP2.5 is proposed in most severe patients.

METHODS

Retrospective single center registry from January 2007 to October 2010. All survivors of out-of-hospital cardiac arrest with patent or predictive factors for the occurrence of post-resuscitation shock assisted by either IMPELLA or intra aortic balloon pump (IABP) device immediately after the coronary angiogram were included.

RESULTS

78 post-cardiac arrest patients were assisted by one of the devices (35 by IMPELLA and 43 by IABP). Median "no flow" and median "low flow" were similar at admission as were hemodynamic parameters. The feasibility of IMPELLA implantation was good (97%). At 28 days, the survival rate without sequellae was 23.0% in the IMPELLA and 29.5% in the IABP group (p=0.61). Vascular complications were observed equally in both groups (3 vs. 2, p=0.9). Serious bleeding complications occurred in 26% of IMPELLA patients vs. 9% of IABP patients (p=0.06).

CONCLUSION

Early LV assistance by the IMPELLA LP2.5 is feasible in patients with post-resuscitation shock. The rate of complications did not differ substantially in the two groups, except for a trend toward a higher rate of bleeding events with IMPELLA. These encouraging findings must be confirmed in a larger clinical study.

Percutaneous Left Ventricular Assist Devices

Percutaneous left ventricular assist devices (P-LVADs) can be life saving and may permit the stabilization of a patient in cardiovascular collapse who would otherwise face imminent demise. For specific patients and clinical indications, or where a greater degree of hemodynamic support is required, numerous studies have demonstrated the feasibility and safety of the newer generation P-LVADs. The potential applications for P-LVADs have continued to expand, now including diverse uses such as support for cardiogenic shock, bridge to and following cardiac surgery, and more novel applications such as complex electrophysiologic mapping and ablation studies of unstable ventricular rhythms.

Use of impella ventricular assist device in patients with severe coronary artery disease presenting with cardiac arrest

Impella (Abiomed, Danvers, MA) is a percutaneously inserted ventricular assist device (VAD). It has been increasingly used in patients with severe heart failure, cardiogenic shock, and high-risk percutaneous intervention (PCI). However, the use and efficacy of Impella in patients with severe coronary artery disease (CAD) presenting with cardiac arrest has rarely been reported.The objective of this study is to report our center experience in using Impella VAD in CAD patients presenting with cardiac arrest. From December 2010 to March 2011, three patients with severe CAD presented to our center with cardiac arrest underwent PCI with Impella support. We reported three cases of severe CAD presenting with cardiac arrest successfully treated with PCI and Impella support. Our experience demonstrated that Impella VAD may play an adjunctive role in obtaining hemodynamic stability in these high-risk patients undergoing PCI. One of the patients was supported to left VAD implantation, and the other two had excellent neurological and functional recovery. Our reports suggest an important role of Impella in cardiac arrest population. Earlier Impella implantation after cardiac arrest might provide cardiac support and tissue perfusion until recovery or high-risk PCI.

A prospective, randomized clinical trial of hemodynamic support with Impella 2.5 versus intra-aortic balloon pump in patients undergoing high-risk percutaneous coronary intervention: the PROTECT II study

BACKGROUND

Although coronary artery bypass grafting is generally preferred in symptomatic patients with severe, complex multivessel, or left main disease, some patients present with clinical features that make coronary artery bypass grafting clinically unattractive. Percutaneous coronary intervention with hemodynamic support may be feasible for these patients. Currently, there is no systematic comparative evaluation of hemodynamic support devices for this indication.

METHODS AND RESULTS

We randomly assigned 452 symptomatic patients with complex 3-vessel disease or unprotected left main coronary artery disease and severely depressed left ventricular function to intra-aortic balloon pump (IABP) (n=226) or Impella 2.5 (n=226) support during nonemergent high-risk percutaneous coronary intervention. The primary end point was the 30-day incidence of major adverse events. A 90-day follow-up was required, as well, by protocol. Impella 2.5 provided superior hemodynamic support in comparison with IABP, with maximal decrease in cardiac power output from baseline of -0.04±0.24 W in comparison with -0.14±0.27 W for IABP (P=0.001). The primary end point (30-day major adverse events) was not statistically different between groups: 35.1% for Impella 2.5 versus 40.1% for IABP, P=0.227 in the intent-to-treat population and 34.3% versus 42.2%, P=0.092 in the per protocol population. At 90 days, a strong trend toward decreased major adverse events was observed in Impella 2.5-supported patients in comparison with IABP: 40.6% versus 49.3%, P=0.066 in the intent-to-treat population and 40.0% versus 51.0%, P=0.023 in the per protocol population, respectively.

CONCLUSIONS

The 30-day incidence of major adverse events was not different for patients with IABP or Impella 2.5 hemodynamic support. However, trends for improved outcomes were observed for Impella 2.5-supported patients at 90 days.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00562016.

Preliminary experience with Impella Recover(®) LP5.0 in nine patients with cardiogenic shock: a new circulatory support system in the intensive cardiac care unit

AIM

Cardiogenic shock is associated with high mortality. We report our experience with the short-term left ventricular axial pump Impella LP5.0 in nine patients with severe ischaemic heart failure.

METHODS

Six patients (group 1) presented with cardiogenic shock at the acute phase of an ST elevation myocardial infarction. Three patients (group 2) had severe ischaemic cardiomyopathy with temporary contra-indication to LVAD or transplantation. We measured haemodynamic and metabolic variables up to 96hours and recorded morbidity, mechanical pump failures, and mortality up to one year postimplantation.

RESULTS

In all patients the Impella LP5.0 was safely placed through the right subclavian artery. Cardiac power output increased from 0.64 (0.07) W to 0.94 (0.44) W and 1.02 (0.30) W at 24 and 72hours, respectively. The Impella LP5.0 remained in place for 12 (7.2) days. In group 1, five patients were in INTERMACS Profile 3 at the time of pump insertion. Three could be weaned and survived. One patient in INTERMACS Profile 1 died of intractable heart failure within hours. In group 2, two of three patients underwent heart transplantation. Haemorrhage requiring transfusions was observed in four patients but only one case was directly related to the Impella LP5.0.

CONCLUSION

Left ventricular assistance with the Impella LP5.0 appears to be well tolerated. It may be especially useful in patients with acute myocardial infarction complicated by cardiogenic shock who achieve INTERMACS Profile 3 with initial treatment.

Long-term safety and sustained left ventricular recovery: long-term results of percutaneous left ventricular support with Impella LP2.5 in ST-elevation myocardial infarction

AIMS

Mechanical left ventricular (LV) unloading may reduce infarct size when combined with primary percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI). The Impella LP2.5 is a novel percutaneous left ventricular assist device. Although the short-term safety and feasibility of this device have been demonstrated, the long-term effects are unknown. The purpose of the current study was to evaluate the long-term effects of the Impella LP2.5 support on the aortic valve and left ventricular ejection fraction (LVEF).

METHODS AND RESULTS

In 2006, 10 patients with anterior STEMI received 3-day support with the Impella LP2.5 after PCI. The control group consisted of 10 comparable patients, treated according to routine care. For the current study, echocardiography was performed and adverse events were recorded. Mean duration of follow-up was 2.9±0.6 years in the Impella group and 3.0±0.3 years in the control group. No differences in aortic valve abnormalities and LVEF were demonstrated between the groups; nevertheless, LVEF increase from baseline was significantly greater in Impella-treated patients (23.6±8.9% versus 6.7±7.0%, P=0.008).

CONCLUSIONS

Three-day support with the Impella LP2.5 is not associated with adverse effects on the aortic valve at long-term follow-up. LVEF was similar in both groups; however, recovery was significantly greater in the Impella group.