Acquired von Willebrand syndrome in cardiogenic shock patients on mechanical circulatory microaxial pump support

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

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

Impella for the Management of Ventricular Septal Defect Complicating Acute Myocardial Infarction: A European Multicenter Registry

Ventricular septal defect (VSD) is a rare but severe complication of myocardial infarction (MI). Temporary mechanical circulatory support (MCS) can be used as a bridge to VSD closure, heart transplantation, or ventricular assist device. We describe the use of Impella device in this context based on a multicenter European retrospective registry (17 centers responded). Twenty-eight post-MI VSD patients were included (Impella device were 2.5 for 1 patient, CP for 20, 5.0 for 5, and unknown for 2). All patients were in cardiogenic shock with multiple organ failure (SAPS II 41 [interquantile range {IQR} = 27-53], lactate 4.0 ± 3.5 mmol/L) and catecholamine support (dobutamine 55% and norepinephrine 96%). Additional temporary MCS was used in 14 patients (50%), mainly extracorporeal life support (ECLS) (n = 9, 32%). Severe bleedings were frequent (50%). In-hospital and 1 year mortalities were 75%. Ventricular septal defect management was surgical for 36% of patients, percutaneous for 21%, and conservative for 43%. Only surgically managed patients survived (70% in-hospital survival). Type and combination of temporary MCS used were not associated with mortality (Impella alone or in combination with intra-aortic balloon pump [IABP] or ECLS, p = 0.84). Impella use in patients with post-MI VSD is feasible but larger prospective registries are necessary to further elucidate potential benefits of left ventricular unloading in this setting.

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.

Three-year experience of catheter-based micro-axial left ventricular assist device, Impella, in Japanese patients: the first interim analysis of Japan registry for percutaneous ventricular assist device (J-PVAD)

Catheter-based micro-axial ventricular assist device Impella® (Abiomed, Danvers, MA) has been used in Japanese patients with drug-refractory acute heart failure (AHF) since 2017. This is the first interim analysis of the ongoing Japan Registry for Percutaneous Ventricular Assist Device (J-PVAD) to investigate the safety and efficacy of Impella support. Between October 2017 and January 2020, 823 Japanese patients, who were treated with the Impella 2.5, CP, or 5.0 pump, were enrolled. The primary endpoints were safety profiles and cumulative 30-day survival. Among them, 44.8% of patients were acute myocardial infarction with cardiogenic shock. The Impella pumps were unable to implant in 4 patients. The Impella 2.5, CP, and 5.0 pumps were used in 72.4%, 6.2%, and 16.6%, respectively, and mean support duration was 8.1 ± 10.2 days. Combination use of Impella and venoarterial extracorporeal membrane oxygenation (VA-ECMO) was applied for 387 patients (47.3%). Pump stop occurred 22 patients (2.7%). Major adverse events included hemolysis (11.2%), hemorrhage/hematoma (6.1%), peripheral ischemia (1.6%), and stroke (1.6%). The overall 30-day survival was 62.2%. Survival of patients with single Impella support was significantly higher than patients with Impella combined with VA-ECMO support (81.1% vs 49.6%; p < 0.01), who had lower blood pressure, lower left ventricular ejection fraction, and higher degree of inotropic support. Results suggest that short-term outcome of Impella support for Japanese patients was favorable with acceptable safety profiles.

ADAMTS13 inhibition to treat acquired von Willebrand syndrome during mechanical circulatory support device implantation

BACKGROUND

Acquired von Willebrand syndrome (aVWS) is common in patients with mechanical circulatory support (MCS) devices. In these patients, the high shear stress in the device leads to increased shear-induced proteolysis of von Willebrand factor (VWF) by A Disintegrin And Metalloprotease with Thrombospondin type 1 repeats, number 13 (ADAMTS13). As a result, the high molecular weight (HMW) VWF multimers are lost, leading to a decreased VWF function and impaired hemostasis that could explain the bleeding complications that are frequently observed in these patients. To counteract this abnormal VWF degradation by ADAMTS13, we developed a novel targeted therapy, using an anti-ADAMTS13 monoclonal antibody (mAb) that inhibits the shear-induced proteolysis of VWF by ADAMTS13.

METHODS

Human or bovine blood was circulated through in vitro MCS device systems with either inhibitory anti-ADAMTS13 mAb 3H9 or 17C7 (20 μg/ml) or control anti-ADAMTS13 mAb 5C11 or phosphate buffered saline (PBS). VWF multimers and function (collagen binding activity) were determined at different time points. Next, Impella pumps were implanted in calves and the calves were injected with PBS and subsequently treated with mAb 17C7. VWF, ADAMTS13, and blood parameters were determined.

RESULTS

We demonstrated that blocking ADAMTS13 could prevent the loss of HMW VWF multimers in in vitro MCS device systems. Importantly, our antibody could reverse aVWS in a preclinical Impella-induced aVWS calf model.

CONCLUSION

Hence, inhibition of ADAMTS13 could become a novel therapeutic strategy to manage aVWS in MCS device patients.

Overview of Mechanical Circulatory Support for the Management of Post-Myocardial Infarction Ventricular Septal Rupture

Post-myocardial infarction ventricular septal rupture (PIVSR) is becoming increasingly rare in the percutaneous coronary intervention era; however, the mortality rates remain high. Surgical repair is the gold standard treatment for PIVSR but is associated with surgical difficulty and high mortality. Therefore, the timing of surgery is controversial (i.e. either undertake emergency surgery or wait for resolution of organ failure and scarring of the infarcted area). Although long-term medical management is usually ineffective, several mechanical circulatory support (MCS) devices have been used to postpone surgery to an optimal timing. Recently, in addition to venous arterial extracorporeal membrane oxygenation (VA-ECMO), new MCS devices, such as Impella (Abiomed Inc., Boston, MA, USA), have been developed. Impella is a pump catheter that pumps blood directly from the left ventricle, in a progressive fashion, into the ascending aorta. VA-ECMO is a temporary MCS system that provides complete and rapid cardiopulmonary support, with concurrent hemodynamic support and gas exchange. When left and right heart failure and/or respiratory failure occur in cardiogenic shock or PIVSR after acute myocardial infarction, ECpella (Impella and VA-ECMO) is often introduced, as it can provide circulatory and respiratory assistance in a shorter period. This review outlines the basic concepts of MCS in PIVSR treatment strategies and its role as a bridge device, and discusses the efficacy and complications of ECpella therapy and the timing of surgery.

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

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

Venting during venoarterial extracorporeal membrane oxygenation

Cardiogenic shock and cardiac arrest contribute pre-dominantly to mortality in acute cardiovascular care. Here, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has emerged as an established therapeutic option for patients suffering from these life-threatening entities. VA-ECMO provides temporary circulatory support until causative treatments are effective and enables recovery or serves as a bridging strategy to surgical ventricular assist devices, heart transplantation or decision-making. However, in-hospital mortality rate in this treatment population is still around 60%. In the recently published ARREST trial, VA-ECMO treatment lowered mortality rate in patients with ongoing cardiac arrest due to therapy refractory ventricular fibrillation compared to standard advanced cardiac life support in selected patients. Whether VA-ECMO can reduce mortality compared to standard of care in cardiogenic shock has to be evaluated in the ongoing prospective randomized studies EURO-SHOCK (NCT03813134) and ECLS-SHOCK (NCT03637205). As an innate drawback of VA-ECMO treatment, the retrograde aortic flow could lead to an elevation of left ventricular (LV) afterload, increase in LV filling pressure, mitral regurgitation, and elevated left atrial pressure. This may compromise myocardial function and recovery, pulmonary hemodynamics—possibly with concomitant pulmonary congestion and even lung failure—and contribute to poor outcomes in a relevant proportion of treated patients. To overcome these detrimental effects, a multitude of venting strategies are currently engaged for both preventive and emergent unloading. This review aims to provide a comprehensive and structured synopsis of existing venting modalities and their specific hemodynamic characteristics. We discuss in detail the available data on outcome categories and complication rates related to the respective venting option.

Graphical abstract

Thrombosed stuck mitral valve during advanced mechanical circulatory support for post-cardiotomy shock

We report a case of mechanical prosthetic mitral valve thrombosis in a 52-year-old woman with previous diagnosis of dilated cardiomyopathy, who was supported with advanced mechanical circulatory support after urgent mechanical mitral valve replacement (MVR) and tricuspid annuloplasty. Difficult weaning from cardiopulmonary bypass needed support with veno-arterial extracorporeal membranous oxygenation and Impella (Abiomed Inc, Danvers, MA, USA), so-called ECPELLA. Temporary discontinuation of heparin and massive blood transfusion were necessary due to four times of reoperation for bleeding during ECPELLA support. Poor recovery of cardiac function needed escalation from ECPELLA to extracorporeal biventricular assist device (ex-BiVAD) using two centrifugal pumps on Day 12. After gradual decrease in the left ventricular assist device flow, transesophageal echocardiography and fluoroscopic images revealed the stuck leaflets of the mitral prosthesis. Therefore, the patient underwent re-MVR with a bioprosthesis on Day 18, followed by continued assistance with ex-BiVAD. The patient was finally weaned from ex-BiVAD on Day 28 and was transferred to the referral hospital for rehabilitation. She was alive in good general condition at 2-year follow-up. It is important to balance the effects of anticoagulation on advanced mechanical circulatory support with ECPELLA, against the side effects of bleeding, especially in post-cardiotomy patients with bleeding tendency. .

Impact of the Severity of Acquired von Willebrand Syndrome on the Short-Term Prognosis in Patients with Temporary Mechanical Circulatory Support

Background and Objectives: Acquired von Willebrand syndrome (AVWS) develops not only in patients with durable ventricular assist devices but also in patients receiving temporary mechanical circulatory support (MCS). However, its prognostic implication remains unknown. Materials and Methods: Patients who received temporary MCS in our institute between August 2018 and September 2021 were included in this prospective study and the von Willebrand factor multimer analyses were performed following the initiation of temporary MCS supports. The von Willebrand factor large-multimer index was calculated as a normalized ratio of large-multimer proportion among total von Willebrand factor. Association between the large-multimer index and the 30-day survival was investigated. Results: A total of 31 patients (69 years old, 52% men) were included. Median large-multimer index was 63.0% (56.9%, 75.6%). The index was lowest in patients with extracorporeal membrane oxygenation than those receiving support from other devices. A lower index (<59.9%) was associated with lower 30-day survival (41.7% versus 94.7%, p = 0.001) with an odds ratio 0.044 (95% confidence interval 0.002–0.805, p = 0.035) adjusted for other potential confounders. Conclusions: An advanced AVWS was associated with lower short-term survival in patients with temporary MCS. The clinical implication of AVWS-guided temporary MCS management remains the next concern.

Role of acquired von Willebrand syndrome in the development of bleeding complications in patients treated with Impella RP devices

Axial flow pumps are standard treatment in cases of cardiogenic shock and high-risk interventions in cardiology and cardiac surgery, although the optimal anticoagulation strategy remains unclear. We evaluated whether laboratory findings could predict bleeding complications and acquired von Willebrand syndrome (avWS) among patients who were treated using axial flow pumps. We retrospectively evaluated 60 consecutive patients who received Impella devices (Impella RP: n = 20, Impella CP/5.0: n = 40; Abiomed Inc., Danvers, USA) between January 2019 and December 2020. Thirty-two patients (53.3%) experienced major or fatal bleeding complications (Bleeding Academic Research Consortium score of > 3) despite intravenous heparin being used to maintain normal activated partial thromboplastin times (40–50 s). Extensive testing was performed for 28 patients with bleeding complications (87.5%). Relative to patients with left ventricular support, patients with right ventricular support were less likely to develop avWS (87.5% vs. 58.8%, p = 0.035). Bleeding was significantly associated with avWS (odds ratio [OR]: 20.8, 95% confidence interval [CI]: 3.3–128.5; p = 0.001) and treatment duration (OR: 1.3, 95% CI 1.09–1.55; p = 0.003). Patients with avWS had longer Impella treatment than patients without avWS (2 days [1–4.7 days] vs. 7.3 days [3.2–13.0 days]). Bleeding complications during Impella support were associated with avWS in our cohort, while aPTT monitoring was not sufficient to prevent bleeding complications. A more targeted anticoagulation monitoring might be needed for patients who receive Impella devices.

Adverse Events of Percutaneous Microaxial Left Ventricular Assist Devices-A Retrospective, Single-Centre Cohort Study

Worldwide, the left ventricular assist device Impella^® (Abiomed, Danvers, MA, USA) is increasingly implanted in patients with acute cardiogenic shock or undergoing high-risk cardiac interventions. Despite its long history of use, few studies have assessed its safety and possible complications associated with its use. All patients treated with a left-sided Impella^® device at the University Hospital of Basel from 1 January 2011 to 31 December 2019 were enrolled. The primary endpoint was the composite rate of mortality and adverse events (bleeding, acute kidney injury, and limb ischemia). Out of 281 included patients, at least one adverse event was present in 262 patients (93%). Rates of in-hospital, 90-day, and one-year mortality were 48%, 47%, and 50%, respectively. BARC type 3 bleeding (62%) and hemolysis (41.6%) were the most common complications. AKI was observed in 50% of all patients. Renal replacement therapy was required in 97 (35%) of all patients. Limb ischemia occurred in 13% of cases. Bleeding and hemolysis are common Impella^®-associated complications. Additionally, we found a high rate of AKI. A careful selection of patients receiving microaxial LV support and defining the indication for its use are essential measures to be taken for the benefits to outweigh potential complications.

Acquired von Willebrand Syndrome

Acquired von Willebrand syndrome can occur in the setting of myeloproliferative neoplasms; plasma cell dyscrasias and other lymphoproliferative disorders; autoimmune conditions; and causes of increased shear forces, such as aortic stenosis or other structural heart disease and mechanical circulatory support. The depletion of von Willebrand factor, especially high-molecular-weight multimers, can lead to mucocutaneous bleeding and the formation of arteriovenous malformations, particularly in the gastrointestinal tract. Management focuses on correction of the underlying cause when possible, but may include intravenous immunoglobulins, von Willebrand factor concentrate, rituximab, or antiangiogenic therapy depending on the clinical context.

Prevention and treatment of pulmonary congestion in patients undergoing venoarterial extracorporeal membrane oxygenation for cardiogenic shock

Cardiogenic shock is still a major driver of mortality on intensive care units and complicates ∼10% of acute coronary syndromes with contemporary mortality rates up to 50%. In the meantime, percutaneous circulatory support devices, in particular venoarterial extracorporeal membrane oxygenation (VA-ECMO), have emerged as an established salvage intervention for patients in cardiogenic shock. Venoarterial extracorporeal membrane oxygenation provides temporary circulatory support until other treatments are effective and enables recovery or serves as a bridge to ventricular assist devices, heart transplantation, or decision-making. In this critical care perspective, we provide a concise overview of VA-ECMO utilization in cardiogenic shock, considering rationale, critical care management, as well as weaning aspects. We supplement previous literature by focusing on therapeutic issues related to the vicious circle of retrograde aortic VA-ECMO flow, increased left ventricular (LV) afterload, insufficient LV unloading, and severe pulmonary congestion limiting prognosis in a relevant proportion of patients receiving VA-ECMO treatment. We will outline different modifications in percutaneous mechanical circulatory support to meet this challenge. Besides a strategy of running ECMO at lowest possible flow rates, novel therapeutic options including the combination of VA-ECMO with percutaneous microaxial pumps or implementation of a venoarteriovenous-ECMO configuration based on an additional venous cannula supplying towards pulmonary circulation are most promising among LV unloading and venting strategies. The latter may even combine the advantages of venovenous and venoarterial ECMO therapy, providing potent respiratory and circulatory support at the same time. However, whether VA-ECMO can reduce mortality has to be evaluated in the urgently needed, ongoing prospective randomized studies EURO-SHOCK (NCT03813134), ANCHOR (NCT04184635), and ECLS-SHOCK (NCT03637205). These studies will provide the opportunity to investigate indication, mode, and effect of LV unloading in dedicated sub-analyses. In future, the Heart Teams should aim at conducting a dedicated randomized trial comparing VA-ECMO support with vs. without LV unloading strategies in patients with cardiogenic shock.

Impact of the whole activated clotting time during Impella support on short-term prognosis

Impella (Abiomed, Danvers, MA, USA) is a percutaneous trans-catheter left ventricular assist device. Anticoagulant therapy targeting whole activated clotting time (ACT) between 160 and 180 s is recommended to prevent pump thrombosis during support. However, we sometimes experience fatal bleeding despite achieving the target ACT range. Consecutive patients who received Impella support in our institute between March 2018 and October 2020 were included in this retrospective study. The association between the averaged ACT levels during the Impella support and 30-day mortality was investigated. A total of 36 patients (71 years old, 61% males) were included. Most of the patients were managed within the recommended therapeutic range of ACT, and the average ACT level was 162 s. The higher ACT group (> 168 s) had older age, smaller body mass index, and higher serum creatinine compared with the lower ACT group (p < 0.05 for all). A higher ACT level was an independent risk factor of 30-day mortality with an adjusted hazard ratio of 1.085 (95% confidence interval 1.037-1.154) with a cut-off level of 168 s. There were only two thromboembolic events. Patients managed with higher ACT levels had a higher risk of 30-day mortality during Impella support. A low-dose heparin purge solution might be recommended in patients with high-risk for bleeding events.

Neurocritical Care of Mechanical Circulatory Support Devices

PURPOSE OF REVIEW

Mechanical circulatory support (MCS) devices have demonstrated improved survival outcomes in otherwise refractory cardiopulmonary failure but are associated with significant neurologic morbidity and mortality. This review aims to characterize MCS-associated brain injury and discuss the neurocritical care of this population.

RECENT FINDINGS

We found no practice guidelines or specific management strategies for the neurocritical care of patients with MCS devices. Acute brain injury was commonly observed in short-term and durable MCS devices. There is emerging evidence that a standardized neurological monitoring and management algorithm for MCS device-associated brain injury is feasible and potentially improves neurological outcomes. While MCS devices are associated with significant neurologic morbidity and mortality, there is scant evidence regarding optimal neuromonitoring and neurocritical care. With the increase in use of MCS devices for both short-term and durable applications, improved outcomes will depend on early identification and intervention of neurologic complications and further research into their pathophysiology.

Mechanical circulatory support with Impella in percutaneous coronary intervention: current status

In patients with, or at risk of, hemodynamic instability during percutaneous coronary intervention, maintaining perfusion of vital organs is crucial. The intra-aortic balloon pump and Impella are the two most commonly used percutaneous mechanical circulatory support devices. Intra-aortic balloon pump has been in widespread use for over three decades. Mechanical circulatory support with Impella is being used increasingly often in patients with acute myocardial infarction complicated by cardiogenic shock, and in those undergoing high-risk percutaneous coronary intervention. Besides improving cardiac output and coronary perfusion, Impella has potential myocardial protective effects. Three key measures that determine the clinical utility of a device are clinical outcome, device-related complications, and cost impact. In this review, the current data on use of Impella in patients with acute myocardial infarction complicated by cardiogenic shock, in left ventricular unloading in acute myocardial infarction, and in those undergoing high-risk percutaneous coronary intervention is analyzed.

Percutaneous Ventricular Assist Device vs. Intra-Aortic Balloon Pump for Hemodynamic Support in Acute Myocardial Infarction-Related Cardiogenic Shock and Coexistent Atrial Fibrillation: A Nationwide Propensity-Matched Analysis'

BACKGROUND

Patients suffering an acute myocardial infarction complicated by cardiogenic shock (AMICS) may experience clinical deterioration with concomitant atrial fibrillation (AF). Recent data suggest that percutaneous ventricular assist devices (pVADs) provide superior hemodynamic support over intra-aortic balloon pump (IABP) in AMICS. In patients with AF+AMICS, however, outcomes data comparing these two devices remain limited.

METHODS

Using the National Inpatient Sample datasets (2008-2014) and a propensity-score matched analysis, we compared the outcomes of AMICS+AF hospitalized patients undergoing PCI with pVAD vs. IABP support.

RESULTS

A total of 12,842 AMICS+AF patients were identified (pVAD=468, IABP=12,374). The matched groups (pVAD=443, IABP=443) were comparable in terms of mean age (70.3 ± 12.0 vs. 70.4 ± 11.0yrs, p = 0.92). The utilization of pVAD was higher in whites but lower in Medicare/Medicaid beneficiaries as compared to IABP. The pVAD group demonstrated higher rates of obesity (13.6% vs. 7.8%, p = 0.006) and dyslipidemia (48.4% vs. 41.8%, p = 0.05). There was no difference in the in-hospital mortality (40.5% vs. 36.8%, p = 0.25); however, pVAD group had a lower incidence of post-procedural MI and higher incidences of stroke (7.8% vs. 4.4%, p = 0.03), hemorrhage (5.6% vs. 2.3%, p = 0.01), discharges to home health care (13.5% vs. 10.1%, p<0.001) and to other facilities (29.1% vs. 24.9%, p<0.001) as compared to IABP group. There was no difference between the groups in terms of mean length of stay or hospital charges.

CONCLUSIONS

All-cause inpatient mortality was similar in AMICS+AF patients undergoing PCI who were treated with either pVAD or IABP. The pVAD group, however, experienced more complications while consuming greater healthcare resources.

Current indication and practical management of percutaneous left ventricular assist device support therapy in Japan

Impella (Abiomed, Danvers, MA, USA) is a recently-innovated (commercially available from 2017 in Japan) percutaneous left ventricular assist device which is inserted percutaneously and transfers blood from the left ventricle to the ascending aorta, improving systemic circulation and end-organ dysfunction as well as unloading left ventricle in patients with cardiogenic shock. Impella has not yet shown a significant survival benefit in patients with cardiogenic shock compared to intra-aortic balloon pump in randomized control trials, but gives powerful circulatory support immediately with minimally invasive manner when used in appropriate patients at optimal timing with adequate management. In this review article, we will introduce and discuss optimal and practical management of Impella therapy in Japan.

Meta-Analysis and Trial Sequential Analysis Comparing Percutaneous Ventricular Assist Devices Versus Intra-Aortic Balloon Pump During High-Risk Percutaneous Coronary Intervention or Cardiogenic Shock

The intra-aortic balloon pump (IABP) and percutaneous ventricular assist devices (pVAD) are commonly used in different clinical scenarios. The goal of this study was to carry out a meta-analysis and Trial Sequential Analysis (TSA) comparing the IABP versus pVAD (TandemHeart and the Impella) during high-risk percutaneous coronary intervention (PCI) or cardiogenic shock (CS). Using PubMed, Cochrane Central Register of Controlled Trials, and EMBASE we searched for randomized clinical trials (RCTs) and nonrandomized studies that compared pVAD versus IABP in patients who underwent high-risk PCI or with CS. We included 5 RCTs and 1 nonrandomized study comparing pVAD versus IABP. Based on the RCTs, we demonstrated no difference in short-term (6 months) (risk ratio [RR] 1.09, 95% confidence interval [CI] 0.79 to 1.52; p = 0.59) or long-term (12 months) (RR 1.00, 95% CI 0.57 to 1.76; p = 1.00) all-cause mortality. The use of pVAD seemed associated with more adverse events (acute kidney injury, limb ischemia, infection, major bleeding, and vascular injury) compared with IABP (RR 1.65, 95% CI 1.14 to 2.39; p = 0.008) but this was not supported by TSA (random-effects RR 1.66, 95% CI 0.89 to 3.09; p = 0.11; TSA-adjusted CI 0.13 to 21.3). In conclusion there were no differences in short or long-term mortality when using IABP versus pVAD for high-risk PCI or CS. IABP showed superiority over pVAD in terms of risk of harm. However, further RCTs are needed to establish more conclusively the role of these modalities of mechanical circulatory support during high-risk PCI or CS.

High Molecular Weight von Willebrand Factor Multimer Loss and Bleeding in Patients with Short-Term Mechanical Circulatory Support Devices: A Case Series

Acquired von Willebrand syndrome (VWS) due to loss of high-molecular-weight multimers (HMWMs) has been reported with longer term mechanical devices and is associated with mucosal bleeding, a primary hemostasis type of bleeding. However, little is known whether a similar defect occurs in patients with short-term mechanical circulatory support (STMCS) devices. We reviewed von Willebrand factor (VWF) profiles in patients with STMCS devices who underwent VWS workup from December 2015 to March 2017 at an academic quaternary care hospital. There were a total of 18 patients (57.0 ± 12.7 years old; 83.3% male) including nine with mucosal bleeding and nine with decreasing hemoglobin. The STMCS devices included Impella (n = 11), Impella and right ventricular assist device (n = 2), and an extracorporeal membrane oxygenator (n = 5). The mean HMWM by quantitative VWF multimer analysis was 3.6% ± 1.3% (normal cutoff: 18-34%). In all 10 cases in which VWF activity, fibrinogen, factor VIII, or VWF antigen level were obtained, they were either normal or elevated. All cases demonstrated high normal or elevated levels of low molecular weight multimers (LMWMs). These findings are consistent with type 2 VWS (qualitative defect). This is the first study that quantitatively describes STMCS device-associated HMWM loss, which may contribute to mucosal bleeding. This finding may have implications for intraoperative management during implantation of longer term devices or heart transplantation or other surgery while on STMCS.

Cardiogenic shock complicating peripartum cardiomyopathy: Importance of early left ventricular unloading and bromocriptine therapy

INTRODUCTION

Acute peripartum cardiomyopathy complicated by cardiogenic shock is a rare but life-threatening disease. A prolactin fragment is considered causal for the pathogenesis of peripartum cardiomyopathy. This analysis sought to investigate the role of early percutaneous mechanical circulatory support with micro-axial flow-pumps and/or veno-arterial extracorporeal membrane oxygenation in combination with the prolactin inhibitor bromocriptine in refractory cardiogenic shock complicating peripartum cardiomyopathy.

METHODS AND RESULTS

In this single-centre analysis, five peripartum cardiomyopathy patients with refractory cardiogenic shock received mechanical circulatory support with either Impella CP microaxial pump only (n=2) or in combination with veno-arterial extracorporeal membrane oxygenation (n=3) in the setting of biventricular failure. All patients were mechanically ventilated. In all cases mechanical circulatory support was combined with bromocriptine therapy and early administration of levosimendan. All patients survived the acute phase of refractory cardiogenic shock. Mechanical circulatory support using a micro-axial pump allowed to significantly reduce catecholamine dosage. Remarkably, early left ventricular support with micro-axial flow-pumps resulted in myocardial recovery whereas delayed Impella (mechanical circulatory support) implantation was associated with poor left ventricular recovery.

CONCLUSION

Mechanical circulatory support in patients with refractory cardiogenic shock complicating peripartum cardiomyopathy was associated with a 30-day survival of 100% and a favourable outcome. Notably, early left ventricular unloading combined with bromocriptine therapy was associated with left ventricular recovery. Therefore, an immediate transfer to a tertiary hospital experienced in mechanical circulatory support in combination with bromocriptine treatment seems indispensable for successful treatment of peripartum cardiomyopathy complicated by cardiogenic shock.