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

Acute Hemodynamic and Echocardiographic Consequences of Impella 5.5 Placement in Patients With Advanced Cardiogenic Shock

We sought to investigate the hemodynamic and echocardiographic consequences of the Impella 5.5 during the acute perioperative period. A retrospective analysis of patients who underwent device implantation at our institution between January 2021 and June 2023 was performed. Hemodynamic and echocardiographic changes were modeled as linear mixed models with random intercepts for patient and fixed as well as random effects of time. Of 87 patients identified, most were male (72, 83%) with nonischemic cardiomyopathy (44, 51%). In the first two postoperative days, the median cardiac output increased by 1.2 L/min (p < 0.05), although the median Impella flow remained at 4.1 L/min. Mean pulmonary artery pressures (32 vs. 27 mm Hg, p < 0.05) and vasoactive inotrope scores (5.6 vs. 3.7, p < 0.01) were modestly reduced. Significant echocardiographic improvement was noted in 61% and 71% of patients with significant preoperative mitral or tricuspid regurgitation, respectively. However, no changes in ejection fraction, left ventricle (LV) diameter, or right ventricular function were noted (all p > 0.05). At 30 days, 27 (31%) patients were transplanted and 13 (15%) were bridged to a durable left ventricular assist device (LVAD). We conclude that in the acute phase following Impella implantation, LV offloading, reductions in pulmonary artery pressures, and improvement in valvular regurgitation are seen without changes to ventricular geometry.

Risk Factors and Outcomes of Invasive Candida Infections in Heart Transplant Recipients: A Case-Control Study

BACKGROUND

Invasive Candida infections (ICI) are the most common invasive fungal infections in solid organ transplant recipients. There are limited contemporary data on the risk factors for infection in heart transplant (HT) recipients especially since the expansion of temporary mechanical circulatory support (MCS) use.

METHODS

This was a case-control study conducted at a tertiary care academic hospital of HT recipients from January 2022 to January 2024. All patients who developed ICI by the detection of Candida species from a normally sterile site were included as cases. Four controls who underwent HT, two before the case and two after the case, were selected. ​Fisher's exact or Mann-U-Whitney tests were used for the analysis.

RESULTS

There were 12 cases and 48 controls out of a total of 117 transplants during the study period​. The proportion of ICI was 10.6%. The median time to ICI from transplant was 16 days (IQR 10, 83). The most common organisms isolated were Candida parapsilosis and Candida albicans. The majority of infections were mediastinitis. Risk factors for ICI included receipt of antibiotics for more than 7 days within 1 month prior to transplant (58.3% vs. 22.9%, p = 0.03), tracheostomy (41.7% vs. 10.4%, p = 0.02), prolonged chest tube placement (13 vs. 9 days, p = 0.02), and temporary MCS (p = 0.042). Patients who developed ICI had increased 90-day all-cause mortality compared to controls (33.3% vs. 4.2%, p = 0.01).

CONCLUSION

This study identified several risk factors for ICI following HT. Further research is essential to develop interventions that mitigate these risk factors in this patient population.

A profile of the impella 5.5 for the clinical management of cardiogenic shock and a review of the current indications for use and future directions

INTRODUCTION

The Impella 5.5 device is a surgically inserted, trans-valvular, microaxial flow device capable of providing 5.5 L/min of continuous, antegrade flow from the left ventricle (LV) to the aorta. The ability of the Impella 5.5 to fully pressure and volume unload the dysfunctional LV while allowing for mobilization and rehabilitation has rapidly expanded its use. Clinical use scenarios include escalation of support for acute myocardial infarction cardiogenic shock (AMICS), transition from extracorporeal membrane oxygenation to mobile support, bridge to transplantation or durable MCS in acute decompensated heart failure, or perioperative use in post-cardiotomy cardiogenic shock (PCCS).

AREAS COVERED

This review provides a profile of the Impella 5.5 device, summarizes the current literature surrounding clinical applications, reviews active and upcoming clinical trials, and projects future applications for the device through an expert review.

EXPERT OPINION

The development of the Impella 5.5 has allowed for monitoring of left-heart recovery, optimizing right ventricular function, and rehabilitating patients to meet bridging endpoints. The 2018 heart transplant allocation system modifications have expanded the use of temporary mechanical circulatory support (tMCS) on the transplant waitlist, increasing the number of patients transplanted on support. With increased safety and durability, an expanding frontier is used in perioperative support for PCCS in high-risk cardiac surgery.

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

INTRODUCTION

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

METHODS AND ANALYSIS

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

ETHICS AND DISSEMINATION

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

Optimizing Perioperative Care for Ventricular Tachycardia Ablation in High-Risk Patients Supported by Impella 5.5

Impella 5.5 (Abiomed Inc., Danvers, MA, USA) is a surgically implanted mechanical circulatory support device that helps support hemodynamically compromised patients. The device's risks and benefits must be entirely known, especially in the electrophysiology lab. Due to unexpected hemodynamic changes during pace mapping and ablation, such as ventricular tachycardia (VT) and asystole, it is sometimes necessary to implement chemical support with inotropic agents such as epinephrine or mechanical support with devices such as an Impella. We present the case of a 72-year-old male with a biventricular implantable cardioverter-defibrillator (ICD) (Medtronic, Minneapolis, MN, USA) placed for refractory VT presenting for VT ablation. He had ischemic cardiomyopathy with a left ventricular ejection fraction (LVEF) of 33% and medical history of cardiac sarcoidosis, hypertension, hyperlipidemia, pulmonary embolism, left bundle branch block, and coronary artery disease. Due to the nature of the procedure and his history of arrhythmia, the patient was deemed a candidate for Impella 5.5. After evaluating patient risk factors, the cardiothoracic anesthesia team developed a strategic approach with imaging (including radiographic and echocardiographic imaging), Impella monitoring, and pharmacologic management with inotropes and vasopressors, allowing for uncomplicated perioperative management during the ablation. Given the procedure's intricacies and the patient's arrhythmia history, the medical team identified the patient as suitable for Impella 5.5 due to better performance and greater cardiac output than Impella 2.5 (Abiomed Inc., Danvers, MA, USA). Following a thorough assessment of the patient's risk factors, the cardiothoracic anesthesia team devised a comprehensive strategy to facilitate smooth perioperative management during the ablation, minimizing complications. The VT ablation procedure was performed successfully and effectively terminated the arrhythmia. However, the patient developed multifaceted postoperative complications, including cardiogenic shock, hemorrhagic shock, dyspnea, anemia, gastrointestinal abnormalities, and sepsis.  This case represents a highly complex patient scenario under the care of the cardiovascular anesthesiologist due to the nature of the procedure and numerous cardiovascular comorbidities, low ejection fraction, ICD placement, and malignant ventricular arrhythmia. We discuss the various perioperative management strategies and how they are tailored to such patients, including pharmacologic intervention, anesthesia administration, imaging modalities, and postoperative care. The purpose of this case report is to delineate the role of Impella 5.5 in perioperative care for high-risk VT ablation patients. We discuss the progression, pathophysiology, and management of this patient's multisystem complications following the procedure. We also highlight the use of Impella 5.5 in the electrophysiology lab and the anesthesia considerations, safeguards, and management strategies to optimize perioperative outcomes and avoid complications.

Surgically implanted endovascular, microaxial left ventricular assist device: A single institution study

Objective

The Impella 5.5 (Abiomed, Inc), a surgically implanted endovascular microaxial left ventricular assist device, is increasingly used worldwide and there have been more than 10,000 implants. The purpose of this study is to describe a large-volume, single-center experience with the use of the Impella 5.5.

Methods

Data were obtained retrospectively from patients supported with the Impella 5.5 implanted at our institution from May 1, 2020, to December 31, 2022. Demographic, operative, and postoperative outcomes for each group are described. Results are reported in median (interquartile range) or n (%). The entire cohort was divided into 5 main groups based on the intention to treat at the time of the Impella 5.5 implantation: (1) patients who had a planned Impella 5.5 implanted at the time of high-risk cardiac surgery; (2) patients with cardiogenic shock; (3) patients bridged to a durable left ventricular assist device; (4) patients bridged to transplant; and (5) patients with postcardiotomy shock who received an unplanned Impella 5.5 implant.

Results

A total of 126 patients were supported with the Impella 5.5. Overall survival to device explant was 76.2%, with 67.5% surviving to discharge. Midterm survival was assessed with a median follow-up time of 318 days and demonstrated an overall survival of 60.3% and a median of 650 days (549-752).

Conclusions

Outcomes after using the Impella 5.5 are variable depending on the indication of use. Patient selection may be of utmost importance and requires further experience with this device to determine who will benefit from insertion.