Intra-Aortic Balloon Pump as a Bridge to Durable Left Ventricular Assist Device.

Left ventricular assist devices (LVAD) are increasingly being used as destination therapy in patients with Stage D heart failure. It has been reported that a majority of patients who receive a durable LVAD (dLVAD) present in cardiogenic shock due to decompensated heart failure (ADHF-CS). As it stands, there is no consensus on the optimal management strategy for patients presenting with ADHF. Bridging with intra-aortic balloon pumps (IABPs) continues to be a therapeutic option in patients with hemodynamic instability due to cardiogenic shock. The majority of data regarding the use of IABP in cardiogenic shock come from studies in patients presenting with acute myocardial infarction with cardiogenic shock and demonstrates that there is no benefit of routine IABP use in this patient population. However, the role of IABPs as a bridge to dLVAD in ADHF-CS has yet to be determined. The hemodynamic changes seen in acute myocardial infarction with cardiogenic shock are known to be different and more acutely impaired than those presenting with ADHF-CS as evidenced by differences in pressure/volume loops. Thus, data should not be extrapolated across these 2 very different disease processes. The aim of this review is to describe results from contemporary studies examining the use of IABPs as a bridge to dLVAD in patients with ADHF-CS. Retrospective evidence from large registries suggests that the use of IABP as a bridge to dLVAD is feasible and safe when compared with other platforms of temporary mechanical circulatory support. However, there is currently a paucity of high-quality evidence examining this increasingly important clinical question.

Mucormycosis after Coronavirus disease 2019 infection in a heart transplant recipient - Case report and review of literature.

Mucormycosis is an invasive fungal infection (IFI) due to several species of saprophytic fungi, occurring in patients with underlying co-morbidities (including organ transplantation). During the ongoing Coronavirus disease 2019 (COVID-19) pandemic, there have been increasing reports of bacterial and fungal co-infections occurring in COVID-19 patients, including COVID-19 associated pulmonary aspergillosis (CAPA). We describe a case of mucormycosis occurring after COVID-19, in an individual who received a recent heart transplant for severe heart failure. Two months after heart transplant, our patient developed upper respiratory and systemic symptoms and was diagnosed with COVID-19. He was managed with convalescent plasma therapy and supportive care. Approximately three months after COVID-19 diagnosis, he developed cutaneous mucormycosis at an old intravascular device site. He underwent extensive surgical interventions, combined with broad-spectrum antifungal therapy. Despite the aggressive therapeutic measures, he died after a prolonged hospital stay. In this case report, we also review the prior well-reported cases of mucormycosis occurring in COVID-19 patients and discuss potential mechanisms by which COVID-19 may predispose to IFIs. Similar to CAPA, mucormycosis with COVID-19 may need to be evaluated as an emerging disease association. Clinicians should be vigilant to evaluate for invasive fungal infections such as mucormycosis in patients with COVID-19 infection.

Impella 5.5 Direct Aortic Implant and Explant Techniques.

The Impella 5.5 with SmartAssist system (Abiomed, Danvers, MA) is approved for the treatment of cardiogenic shock after acute myocardial infarction, cardiac surgery, or in the setting of cardiomyopathy. Designed for full circulatory support and left ventricular unloading the system comprises a catheter-based microaxial pump placed across the aortic valve, pulling blood from the left ventricle and into the ascending aorta. Implantation can be approached through the axillary artery or directly into the aortic root. We present several technical options for implanting, tunneling, and explanting the system using the direct aortic approach and allowing for bedside removal.

The Rise of Endovascular Mechanical Circulatory Support Use for Cardiogenic Shock and High Risk Coronary Intervention: Considerations and Challenges.

Introduction: Cardiogenic shock due to acute myocardial infarction and decompensated advanced heart failure remains a source of significant morbidity and mortality. Endovascular mechanical circulatory support devices including intra-aortic balloon pump (IABP), percutaneous left ventricular assist devices (Impella and Tandemheart pumps), and veno-arterial extracorporeal oxygenation (VA-ECMO) are utilized for a broadening range of indications.Areas covered: This narrative review explores the specific devices, their distinctive hemodynamic profiles, and practical considerations. Furthermore, reviewed are the trials evaluating device outcomes which have generated significant controversy within the field of heart failure and shock. New applications and future directions are discussed.Expert opinion: Use of endovascular mechanical circulatory support has increased over the last decade, though evidence supporting their use is lacking. Development of large-scale prospective registries and clinical classification systems will facilitate patient enrollment and inform trial design. Furthermore, expansion of indications for these devices is revolutionizing how the field of heart failure and cardiogenic shock thinks about hemodynamic support. The ability to tailor therapy to a patient's specific hemodynamic profile appears to be the future of cardiogenic shock management.

Intra-aortic balloon pump: Looking at the other side.

Intra-aortic balloon pump has been the most commonly employed cardiac assist device in the past, although, in recent years, its use in cardiogenic shock has been questioned. The pathophysiology of the proximal part of the balloon has been well studied, whereas, hemodynamics and flow below the distal portion of the balloon have not been fully understood yet. The distal flow contains a three-wave flow pattern during diastolic balloon expansion: a flow reduction in early diastole, a backflow in mid-diastole followed by a tele-diastolic flow. More research on this topic is warranted to better understand the physics of the distal part of the balloon and its interaction with the three components of the local regulatory system: intrinsic (local metabolic and myogenic), extrinsic (autonomic nervous system), and humoral (local or circulating vasoactive substances). These new insights will be a guide for new balloon designs that will allow enhanced performance and improved outcomes.

Currently Available Options for Mechanical Circulatory Support for the Management of Cardiogenic Shock.

Cardiogenic shock (CS) is a complex condition with a high risk for morbidity and mortality. Mechanical circulatory support (MCS) devices were developed to support patients with CS in cases refractory to treatment with vasoactive medications. Current devices include intra-aortic balloon pumps, intravascular microaxial pumps, percutaneous LVAD, percutaneous RVAD, and VA ECMO. Data from limited observational studies and clinical trials show a clear difference in the level of hemodynamic support offered by each device. However, at this point, there are insufficient clinical trial data to guide MCS selection and, until ongoing clinical trials are completed, use of the right device for the right patient depends largely on clinical judgment.

The New Era of Cardiogenic Shock: Progress in Mechanical Circulatory Support.

PURPOSE OF REVIEW: In recent decades, multiple left and right ventricular assist devices (VAD) have been developed, and the utilization of these devices has grown exponentially. We discuss the most common temporary mechanical circulatory support (tMCS) devices used for patients in cardiogenic shock, including the intra-aortic balloon pump (IABP), transvalvular axial flow support systems (Impella®), the Tandem™ collection, and extracorporeal membrane oxygenation (ECMO). RECENT FINDINGS: In 2018 the United Network for Organ Sharing (UNOS) introduced new listing criteria for candidates awaiting heart transplantation in the USA. Analysis of the first 1300 transplants under these new listing criteria has shown that higher-risk patients are now undergoing transplantation. As technology has advanced, becoming more sophisticated and miniaturized, a new era has emerged with more rapidly deployable tMCS devices. For some patients presenting in cardiogenic shock, support with these tMCS devices can be a bridge to a more durable option. For others, their only option may be support with the hope of native cardiac recovery. Understanding the pros and cons of each device can lead to most appropriate utilization for the ultimate intended goal.

Mechanical circulatory support devices in advanced heart failure: 2020 and beyond.

Substantial progress in the field of mechanical circulatory support (MCS) has expanded the treatment options for patients with advanced-stage heart failure (HF). Currently available MCS devices can be implanted percutaneously or surgically. They can also be configured to support the left, right, or both ventricles, offering varying levels of circulatory support. Short-term temporary MCS devices are primarily used in high-risk percutaneous coronary intervention, cardiogenic shock, and post-cardiac arrest, while durable left ventricular assist systems (LVAS) are increasingly utilized either as a bridge-to-transplant, bridge to decision, or as a destination therapy. The evolution from older pulsatile devices to continuous-flow LVAS and the incorporation of smaller pumps, with no valves, fewer moving parts, and improved hemocompatibility has translated into improved clinical outcomes, greater durability, fewer adverse events, and reduced overall cost of care. However, despite marked advances in device design and clinical management, determining MCS candidacy is often difficult and requires the integration of clinical, biomarker, imaging, exercise, and hemodynamic data. This review aims to provide a summary of the current use of short-term and durable MCS devices in the treatment of advanced-stage HF, highlighting several aspects of LVAS support and the challenges that remain.

Trends in first-time hospitalization, management, and short-term mortality in acute myocardial infarction-related cardiogenic shock from 2005 to 2017: A nationwide cohort study.

BACKGROUND: Cardiogenic shock remains the leading cause of in-hospital death in acute myocardial infarction (AMI). Because of temporary changes in management of cardiogenic shock with widespread implementation of early revascularization along with increasing attention to the use of mechanical circulatory devices, complete and longitudinal data are important in this subject. The objective of this study was to examine temporal trends of first-time hospitalization, management, and short-term mortality for patients with AMI-related cardiogenic shock (AMICS). METHODS: Using nationwide medical registries, we identified patients hospitalized with first-time AMI and cardiogenic shock from January 1, 2005, through December 31, 2017. We calculated annual incidence proportions of AMICS. Thirty-day mortality was estimated with use of Kaplan-Meier estimator comparing AMICS and AMI-only patients. Multivariable Cox regression models were used to assess mortality rate ratios. RESULTS: We included 101,834 AMI patients of whom 7,040 (7%) had AMICS. The median age was 72 (interquartile range: 62-80) for AMICS and 69 (interquartile range: 58-79) for AMI-only patients. The gender composition was similar between AMICS and AMI-only patients (male: 64% vs 63%). The annual incidence proportion of AMICS decreased slightly over time (2005: 7.0% vs 2017: 6.1%, P for trend < .0001). In AMICS, use of coronary angiography increased between 2005 and 2017 from 48% to 71%, as did use of left ventricular assist device (1% vs 10%) and norepinephrine (30% to 70%). In contrast, use of intra-aortic balloon pump (14% vs 1%) and dopamine (34% vs 20%) decreased. Thirty-day mortality for AMICS patients was 60% (95% CI: 59-61) and substantially higher than the 8% (95% CI: 7.8-8.2) for AMI-only patients (mortality rate ratio: 11.4, 95% CI: 10.9-11.8). Over time, the mortality decreased after AMICS (2005: 68% to 2017: 57%, P for temporal change in adjusted analysis < .0001). CONCLUSIONS: We observed a slight decrease in AMICS hospitalization over time with changing practice patterns. Thirty-day mortality was markedly higher for patients with AMICS compared with AMI only, yet our results suggest improved 30-day survival over time after AMICS.

Balloon Pump Counterpulsation Part II: Perioperative Hemodynamic Support and New Directions.

Intraaortic balloon pump (IABP) counterpulsation, introduced more than 50 years ago, remains the most commonly utilized mechanical circulatory support device for patients with cardiogenic shock and myocardial ischemia, despite lack of definitive proof regarding its outcome in these patients. Part I of this review focused on the history of counterpulsation, physiologic principles, technical considerations, and evidence for its use in cardiogenic shock; Part II will discuss periprocedural uses for IABP counterpulsation and review advances in technology, including the emergence of alternative mechanical circulatory support devices that have influenced IABP utilization.

Intra-aortic balloon counterpulsation timing: A new numerical model for programming and training in the clinical environment.

BACKGROUND AND OBJECTIVE: The intra-aortic balloon pump (IABP) is the most widely available device for short-term mechanical circulatory support, often used to wean off cardiopulmonary bypass or combined with extra-corporeal membrane oxygenation support or as a bridge to a left ventricular assist device. Although based on a relatively simple principle, its complex interaction with the cardiovascular system remains challenging and open to debate. The aim of this work was focused on the development of a new numerical model of IABP. METHODS: The new model was implemented in CARDIOSIM©, which is a modular software simulator of the cardiovascular system used in research and e-learning environment. The IABP is inserted into the systemic bed divided in aortic, thoracic and two abdominal tracts modelled with resistances, inertances and compliances. The effect induced by the balloon is reproduced in each tract of the aorta by the presence of compliances connected to PIABP generator and resistances. PIABP generator reproduces the balloon pressure with the option to change IABP timing. We have used literature data to validate the potential of this new numerical model. RESULTS: The results have shown that our simulations reproduced the typical effects induced during IABP assistance. We have also simulated the effects induced by the device on the hemodynamic variables when the IABP ratio was set to 1:1, 1:2, 1:4 and 1:8. The outcome of these simulations is in accordance with literature data measured in the clinical environment. CONCLUSIONS: The new IABP module is easy to manage and can be used as a training tool in a clinical setting. Although based on literature data, the outcome of the simulations is encouraging. Additional work is ongoing with a view to further validate its features. The configuration of CARDIOSIM© presented in this work allows the simulation of the effects induced by mechanical ventilatory assistance. This facility may have significant importance in the management of patients affected by COVID-19 when they require mechanical circulatory support devices.

Acute Mechanical Circulatory Support for Cardiogenic Shock.

Cardiogenic shock is associated with significant morbidity and mortality, and clinicians have increasingly used short-term mechanical circulatory support (MCS) over the last 15 years to manage outcomes. In general, the provision of greater hemodynamic support comes with device platforms that are more complex and potentially associated with more adverse events. In this review, we compare and contrast the available percutaneous and surgically placed device types used in cardiogenic shock and discuss the associated clinical and hemodynamic data to support device use.

Physiological Concepts of Cardiogenic Shock Using Pressure-Volume Loop Simulations: A Case-Based Review.

Cardiogenic shock (CS) is a complex syndrome of end-organ hypoperfusion that requires timely and thorough decision making. While many pathophysiologic and technical principles have been delineated in this issue, the purpose of this case-based report is to reflect upon some of these principles in the context of real-life scenarios. Given the obvious lacuna of evidence-based recommendations in CS, the authors provide a rationale for their decision-making process. The first case is a young post-heart-transplant patient with graft failure who was in a state of biventricular failure and restrictive physiology and required acute mechanical circulatory support (MCS). The second case is a patient who suffered a mechanical complication after experiencing an acute myocardial infarction that required MCS.

Acute Kidney Injury in Cardiogenic Shock.

This column is supplied by Amol Patel, DO, and Peter Nguyen, MD. Dr. Patel is an internal medicine resident at Houston Methodist Hospital, where he is in his final year as chief resident. He received his bachelor's degree in biomedical engineering at Texas A&M University and his medical degree at UNT Health Science center in Forth Worth, Texas. Dr. Nguyen is a nephrologist with Houston Kidney Consultants and practices at Houston Methodist Hospital, where he is currently the secretary of the medical staff. He obtained his medical degree from Texas Tech School of Medicine and completed his residency and nephrology fellowship at Baylor College of Medicine in Houston, Texas.

Percutaneous Left Axillary Artery Placement of Intra-Aortic Balloon Pump in Advanced Heart Failure Patients.

OBJECTIVES: This study presents the largest clinical experience of percutaneously placed axillary intra-aortic balloon pump (IABP) in patients with advanced heart failure. BACKGROUND: Transfemoral placement of IABP limits mobility and recuperation in patients who need prolonged support. We had previously reported a novel percutaneous method of IABP placement in the axillary artery and now present our expanded experience with this technique. METHODS: We performed a retrospective chart review of patients with advanced heart failure with percutaneous axillary IABP placement from November 2007 to June 2018 at Houston Methodist Hospital. We defined successful cardiac replacement therapy as heart transplant or left ventricular assist device implantation. We compared patients who had successful cardiac replacement with those who died and those who needed unplanned escalation of mechanical circulatory support. RESULTS: Of the 195 patients identified, 133 (68%) underwent successful cardiac replacement (120 transplants and 13 left ventricular assist device) as planned. End-organ function improved on IABP support in patients bridged to next therapy. There were 16 patients that died while on IABP support and 18 needed escalation of support. Higher right atrial/wedge ratio, higher right atrial pressure, smaller left ventricular end diastolic dimension, and ischemic cardiomyopathy were associated with death on the IABP in multivariate analysis. Post-transplant and post left ventricular assist device survival for those bridged successfully was 87% and 62%, respectively. Although bedside repositioning was frequent, 37% needed replacement for malfunction. Vascular complications occurred in a minority. CONCLUSIONS: Percutaneous axillary approach for IABP placement is a feasible strategy for prolonged mechanical circulatory support in patients with advanced heart failure.