Case report of increased left ventricular end-diastolic pressure with pulsatile left ventricular assist device

Background

Left ventricular assist devices (LVADs) are increasingly utilized in cardiogenic shock and high-risk percutaneous coronary interventions (PCIs). These devices aspirate and expel blood from the left ventricle (LV) into the aorta, consequently reducing left ventricular end-diastolic pressure (LVEDP). We report a case of unexpected LVEDP rise under LV-to-aorta LVAD in the context of transcatheter aortic valve implantation (TAVI) and concomitant multi-vessel PCI.

Case summary

A patient with acute heart failure, severely depressed systolic LV function, severe aortic stenosis, and multi-vessel coronary artery disease underwent TAVI and concomitant PCI under pulsatile LVAD. Notably, the patient experienced unexpected shortness of breath and elevated LVEDP while under LVAD, which normalized immediately upon LVAD removal.

Discussion

Pulsatile LVAD enhances cardiac output by providing pulsatile support through a percutaneous bi-directional flow catheter. Despite expectations of reduced LVEDP and improved myocardial oxygen supply under LVAD support, we observed high LVEDP and clinical complaints of shortness of breath following TAVI and multi-vessel PCI. This case illustrates that an LVAD across the aortic valve may immobilize aortic leaflets and generate acute aortic regurgitation.

Percutaneous Mechanical Circulatory Support in Acute Heart Failure Complicated with Cardiogenic Shock

Despite advancements in algorithms concerning the management of cardiogenic shock, current guidelines still lack the adequate integration of mechanical circulatory support devices. In recent years, more and more devices have been developed to provide circulatory with or without respiratory support, when conservative treatment with inotropic agents and vasopressors has failed. Mechanical circulatory support can be contemplated for patients with severe, refractory, or acute-coronary-syndrome-related cardiogenic shock. Through this narrative review, we delve into the differences among the types of currently used devices by presenting their notable advantages and inconveniences. We address the technical issues emerging while choosing the best possible device, temporarily as a bridge to another treatment plan or as a destination therapy, in the optimal timing for each type of patient. We also highlight the diverse implantation and removal techniques to avoid major complications such as bleeding and limb ischemia. Ultimately, we hope to shed some light in the gaps of evidence and the importance of conducting further organized studies around the topic of mechanical circulatory support when dealing with such a high mortality rate.

Mechanical Circulatory Support for High-Risk Percutaneous Coronary Intervention

PURPOSE OF REVIEW

This review will focus on the indications of mechanical circulatory support (MCS) for high-risk percutaneous coronary intervention (PCI) and then analyze in detail all MCS devices available to the operator, evaluating their mechanisms of action, pros and cons, contraindications, and clinical data supporting their use.

RECENT FINDINGS

Over the last decade, the interventional cardiology arena has witnessed an increase in the complexity profile of the patients and lesions treated in the catheterization laboratory. Patients with significant comorbidity burden, left ventricular dysfunction, impaired hemodynamics, and/or complex coronary anatomy often cannot tolerate extensive percutaneous revascularization. Therefore, a variety of MCS devices have been developed and adopted for high-risk PCI. Despite the variety of MCS available to date, a detailed characterization of the patient requiring MCS is still lacking. A precise selection of patients who can benefit from MCS support during high-risk PCI and the choice of the most appropriate MCS device in each case are imperative to provide extensive revascularization and improve patient outcomes. Several new devices are being tested in early feasibility studies and randomized clinical trials and the experience gained in this context will allow us to provide precise answers to these questions in the coming years.

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

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

Temporary Mechanical Circulatory Support: Left, Right, and Biventricular Devices

Temporary mechanical circulatory support (MCS) encompasses a wide array of invasive devices, which provide short-term hemodynamic support for multiple clinical indications. Although initially developed for the management of cardiogenic shock, indications for MCS have expanded to include prophylactic insertion prior to high-risk percutaneous coronary intervention, treatment of acute circulatory failure following cardiac surgery, and bridging of end-stage heart failure patients to more definitive therapies, such as left ventricular assist devices and cardiac transplantation. A wide variety of devices are available to provide left ventricular, right ventricular, or biventricular support. The choice of a temporary MCS device requires consideration of the clinical scenario, patient characteristics, institution protocols, and provider familiarity and training. In this review, the most common forms of left, right, and biventricular temporary MCS are discussed, along with their indications, contraindications, complications, cannulations, hemodynamic effects, and available clinical data.

Comparison of a pulsatile and a continuous flow left ventricular assist device in high-risk PCI

BACKGROUND

Mechanical circulatory support devices are able to generate additional cardiac output or maintain sufficient circulation during high-risk PCI. We prospectively compared the hemodynamic and clinical performance of the new iVAC2L® device with the Impella 2.5® device during high-risk PCI.

MATERIALS AND METHODS

In 40 patients [10 female, age 75 ± 8 years, left ventricular ejection fraction (LVEF) 44 ± 11%] high-risk PCIs were performed under iVAC (n = 20) or Impella (n = 20) support. Hemodynamic parameters were collected before and after device placement as well as immediately after PCI. Blood parameters of hemolysis were analyzed before and after support.

RESULTS

Correct device placement was achieved in 17 patients (85%) under iVAC use and in 19 patients (95%) under Impella use. PCI success was 98%. Under iVAC2L® support, systolic, diastolic and mean aortic blood pressure increased significantly with increasing support time. In contrast, aortic pressure increased directly under Impella support, but the increase was comparable between both devices. Impella support generated a significantly higher additional blood flow, as compared to iVAC support (2.07 ± 0.09 l/min vs. 1.25 ± 0.05 l/min, p < 0.001). Five patients (iVAC n = 3) suffered from critical events during high-risk PCI, but both devices were able to maintain stable hemodynamic conditions. After PCI, one severe bleeding occurred in each group. After Impella support, haptoglobin was significantly decreased, indicating potential hemolysis.

CONCLUSIONS

High-risk PCIs under support by both devices are feasible and safe and ensure stable hemodynamic conditions also if complications occur. Aortic pressure increases significantly with both devices, but later under iVAC use. Potential hemolysis occurs more frequent under Impella support.

Effectiveness and Safety of a Prolonged Hemodynamic Support by the IVAC2L System in Healthy and Cardiogenic Shock Pigs

Background

Mechanical circulatory supports are used in case of cardiogenic shock (CS) refractory to conventional therapy. Several devices can be employed, but are limited by their availability, benefit risk-ratio, and/or cost.

Aims

To investigate the feasibility, safety, and effectiveness of a long-term support by a new available device (IVAC2L) in pigs.

Methods

Experiments were carried out in male pigs, divided into healthy (n = 6) or ischemic CS (n = 4) groups for a median support time of 34 and 12 h, respectively. IVAC2L was implanted under fluoroscopic and TTE guidance under general anesthesia. CS was induced by surgical ligation of the left anterior descending artery. An ipsilateral lower limb reperfusion was created with the Solopath® system. Reperfusion was started after 1 h of support in healthy pigs and upon IVAC2L insertion in CS pigs. Hemodynamic and biological parameters were monitored before and during the whole period of support in each group.

Results

Occurrence of an ipsilateral lower limb ischemia was systematic in healthy and CS pigs in a few minutes after IVAC2L implantation, and could be reversed by the arterial reperfusion, as demonstrated by distal transcutaneous pressure in oxygen (TcPO₂) and lactate normalization. IVAC2L support decreased pulmonary capillary wedge pressure (PCWP) (15.3 ± 0.3 vs. 7.5 ± 0.9 mmHg, p < 0.001), increased systolic blood pressure (SBP) (70 ± 4.5 vs. 101.3 ± 3.1 mmHg, p < 0.01), and cardiac output (CO) (4.0 ± 0.3 vs. 5.2 ± 0.6 l/min, p < 0.05) in CS pigs; at CS onset and after 12 h of support, without effects on heart rate or pulmonary artery pressure (PAP). Non-sustained ventricular arrhythmias were frequent at implantation (50%). A non-significant hemolysis was observed under support in CS pigs. Bleedings were frequent at the insertion and/or operating sites (30%).

Conclusion

Long-term support by IVAC2L is feasible and associated with a significant hemodynamic improvement in a porcine model. These preclinical data open the door for a study of IVAC2L in human ischemic CS, keeping in mind the need for systematic reperfusion of the lower limb and the associated risk of bleeding.

Concept and Design of a Novel Pulsatile Left Heart Assist Device-The PERKAT Left Ventricle System

Cardiogenic shock is associated with high mortality. Patients often require temporary mechanical circulatory support. We aimed to develop a percutaneously implantable, assist device that unloads the left ventricle (LV) in a pulsatile way. The PERkutane KATheter pump technologie (PERKAT LV) device consists of a nitinol pump chamber, which is covered by foils carrying outflow valves. A flexible tube with a pigtail-shaped tip and inflow holes represents the distal part of the pump. The system is designed for 16F percutaneous implantation. The nitinol chamber is placed in the descending aorta while the flexible tube bypasses aortic arch and ascending aorta with its tip in the LV. An intra-aortic balloon pump is placed into the chamber and connected to a console. Balloon deflation generates a blood flow from the LV into the pump chamber. During balloon inflation, blood leaves the system through the outflow foil valves in the descending aorta. Under different afterload settings using a 30 cc intra-aortic balloon pump and varying inflation/deflations rates, we recorded flow rates up to 3.0 L/min. Based on this, we believe that PERKAT LV is a promising approach for temporary LV support. The proposed design and its excellent performance give basis for in vivo tests in an animal model.

Temporary Mechanical Circulatory Support as a Bridge to Heart Transplant or Durable Left Ventricular Assist Device

Advanced heart failure refractory to medical therapy can result in patients presenting with progressively worsening hypoperfusion and cardiogenic shock. Temporary mechanical circulatory support is often necessary as a bridge to heart transplant or durable ventricular assist devices. These devices increase cardiac output. Several options are available for left ventricular support. With the exception of venoarterial extracorporeal membrane oxygenation, all other devices decrease left ventricular end-diastolic pressure. The choice of device should be driven by patient needs and the treating teams comfort. Timely identification of cardiogenic shock and use of shock teams are potential strategies that can help improve survival.

Prophylactic veno-arterial extracorporeal membrane oxygenation in patients undergoing high-risk percutaneous coronary intervention

PURPOSE

Complex high-risk percutaneous coronary intervention (PCI) is challenging and frequently accompanied by haemodynamic instability. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) can provide cardiopulmonary support in high-risk PCI. However, the outcome is unclear.

METHODS

A two-centre, retrospective study was performed of all patients undergoing high-risk PCI and receiving VA-ECMO for cardiopulmonary support.

RESULTS

A total of 14 patients (92% male, median age 69 (53-83) years), of whom 50% had previous coronary artery disease in the form of a coronary artery bypass graft (36%) and a PCI (14%) underwent high-risk PCI and received VA-ECMO support. The main target lesion was a left main coronary artery in 78%, a left anterior descending artery in 14%, a right coronary artery in 7%, and 71% underwent multi-vessel PCI in addition to main target vessel PCI. The median SYNTAX score was 27.2 (8-42.5) and in 64% (9/14) there was a chronic total occlusion. Left ventricular function was mildly impaired in 7% (1/14), moderately impaired in 14% (2/14) and severely impaired in 64% (9/14). Cannulation was femoral-femoral in all patients. Median ECMO run was 2.57 h (1-4). Survival was 93% (13/14). One patient died during hospitalisation due to refractory cardiac failure. All other patients survived to discharge. Complications occurred in 14% (2/14), with one patient developing a transient ischaemic attack post-ECMO and one patient developing a thrombus in the femoral vein used for ECMO cannulation.

CONCLUSION

VA-ECMO in high-risk PCI is feasible with a good outcome. It can be successfully used for cardiopulmonary support in selected patients.

Temporary Mechanical Circulatory Support in Acute Heart Failure

Cardiogenic shock (CS) is a challenging syndrome, associated with significant morbidity and mortality. Although pharmacological therapies are successful and can successfully control this acute cardiac illness, some patients remain refractory to drugs. Therefore, a more aggressive treatment strategy is needed. Temporary mechanical circulatory support (TCS) can be used to stabilise patients with decompensated heart failure. In the last two decades, the increased use of TCS has led to several kinds of devices becoming available. However, indications for TCS and device selection are part of a complex process. It is necessary to evaluate the severity of CS, any early and prompt haemodynamic resuscitation, prior TCS, specific patient risk factors, technical limitations and adequacy of resources and training, as well as an assessment of whether care would be futile. This article examines options for commonly used TCS devices, including intra-aortic balloon pumps, a pulsatile percutaneous ventricular assist device (the iVAC), veno-arterial extra-corporeal membrane oxygenation and Impella (Abiomed) and TandemHeart (LivaNova) percutaneous ventricular assist device.

PulseCath iVAC2L: next-generation pulsatile mechanical circulatory support

Contemporary state of the art percutaneous coronary intervention techniques offer treatment strategies and solutions to an increasing number of patients with heart failure and complex coronary artery disease. Percutaneous mechanical circulatory support is intended to alleviate the mechanical and energetic workload imposed to a failing ventricle by reducing left ventricle pressures and volumes and potentially also increasing coronary blood flow. The PulseCath iVAC2L is a transaortic left ventricular assist device that applies a pneumatic driving system to produce pulsatile forward flow. Herein, the essential aspects regarding iVAC2L are discussed with focus on its mechanisms of action and the available clinical experience.

High-risk PCI under support of a pulsatile left ventricular assist device - First German experience with the iVAC2L system

BACKGROUND

During high-risk percutaneous coronary intervention (PCI) complications may occur, leading to unstable hemodynamic conditions. Circulatory support devices might help to intercept these conditions by supporting cardiac output. We investigated in a prospective trial the performance of the pulsatile iVAC2L system in the setting of high-risk PCI.

METHODS

Circulatory support by the iVAC2L device was attempted in 20 consecutive patients (three females, mean age 72 ± 9 years, LVEF 44 ± 12%) undergoing high-risk PCI. Aortic pressure data were collected after device placement and immediately after PCI.

RESULTS

Successful device placement was achieved in 17 (85%) patients; kinking of iliac artery and device length limited correct device placement in the remaining three patients. PCI success was 100%. With ongoing support (overall support time 122 ± 32min) systolic, diastolic and mean blood pressure increased significantly and kept the higher level until device removal. Critical events occurred in three patients (massive vasospasm, coronary perforation, no-flow in LCA after wire placement), but the iVAC2L device helped to maintain stable hemodynamic conditions with no need for cardiopulmonary resuscitation. Serial controls of hemolysis related parameters in a subgroup of ten patients revealed no significant device related hemolysis after the performance of the iVAC2l system.

CONCLUSIONS

High-risk PCI under hemodynamic support by the iVAC2L device is feasible and safe. Aortic pressure increases with ongoing support. The device helps to stabilize hemodynamic situations if complications occur.

Primary intra-aortic balloon support versus inotropes for decompensated heart failure and low output: a randomised trial

AIMS

The haemodynamic effects of primary implantation of an intra-aortic balloon pump (IABP) versus inotropes in decompensated heart failure and low output (DHF-LO), but without an acute coronary syndrome, have not been investigated. We therefore aimed to investigate the effect of primary IABP implantation as compared to inotropes on haemodynamics in DHF-LO with no acute ischaemia.

METHODS AND RESULTS

Patients (n=32) with DHF-LO despite IV diuretics were randomised to primary 50 mL IABP or inotropes (INO: enoximone or dobutamine). The primary endpoint was the improvement of organ perfusion assessed by ∆ mixed-venous oxygen saturation (SvO2) at 3 hours; secondary endpoints included ∆ cardiac power output (CPO), NT-proBNP proportional change, cumulative fluid balance and ∆ dyspnoea severity score, all at 48 hours. Data are presented as median (IQR). Patients were 60 (48-69) years old and 72% were male. Baseline SvO2 was 44 (39-53)%. ∆SvO2 was higher in the IABP group (+17 [+9; +24] vs. +5 [+2; +9]%, p<0.05). IABP patients had a higher ∆CPO, a greater relative reduction in NT-proBNP, a more negative cumulative fluid balance, and a greater reduction in dyspnoea severity score. There were no IABP-related serious adverse events (SAEs). Thirty-day mortality was 23% (IABP) vs. 44% (INO).

CONCLUSIONS

Primary circulatory support by IABP showed a significant increase in improved organ perfusion assessed by SvO2.

New-generation mechanical circulatory support during high-risk PCI: a cross-sectional analysis

AIMS

The aim of the study was to establish the value of new-generation mechanical circulatory support (MCS) devices such as HeartMate PHP, Impella CP and PulseCath iVAC2.

METHODS AND RESULTS

We retrospectively analysed all consecutive elective high-risk PCI procedures performed in the Erasmus Medical Center (2011-2018) in order to compare MCS protected and unprotected patients. The primary endpoint was a composite of procedure-related adverse events including death (<24 hours), cardiac arrest, need for vasopressors, rescue MCS, endotracheal intubation and limb ischaemia with need for surgery. Secondary endpoints included 30-day survival. A total of 198 elective high-risk PCI patients were included (69 [35%] MCS protected, 129 [65%] MCS unprotected). When compared with unprotected patients, MCS protected patients had a significantly worse left ventricular ejection fraction (LVEF) (25±10 vs 33±8%, p<0.01) and higher SYNTAX I score (33±11 vs 24±8, p<0.01). The primary endpoint occurred in 26 (20%) of the unprotected patients and in 6 (9%) of the MCS protected patients (OR 0.38, 95% CI: 0.15-0.97, p=0.04). Patients under 75 years of age, with a SYNTAX I score above 32 and with an LVEF below 30% showed most potential benefit from MCS. Survival during the first 24 hours after the procedure and at 30 days was significantly higher in MCS protected patients (100% vs 95%, p=0.04 at 24 hours, and 98% vs 87%, OR 10.32, 95% CI: 1.34-79.31, p=0.006 at 30 days).

CONCLUSIONS

In a consecutive real-world cohort of high-risk PCI patients, protection with new-generation MCS resulted in better procedural outcomes despite worse EF and more complex coronary artery disease at baseline. Larger prospective studies are needed to confirm these findings.

Utilization of Percutaneous Mechanical Circulatory Support Devices in Cardiogenic Shock Complicating Acute Myocardial Infarction and High-Risk Percutaneous Coronary Interventions

Given the tremendous progress in interventional cardiology over the last decade, a growing number of older patients, who have more comorbidities and more complex coronary artery disease, are being considered for technically challenging and high-risk percutaneous coronary interventions (PCI). The success of performing such complex PCI is increasingly dependent on the availability and improvement of mechanical circulatory support (MCS) devices, which aim to provide hemodynamic support and left ventricular (LV) unloading to enable safe and successful coronary revascularization. MCS as an adjunct to high-risk PCI may, therefore, be an important component for improvement in clinical outcomes. MCS devices in this setting can be used for two main clinical conditions: patients who present with cardiogenic shock complicating acute myocardial infarction (AMI) and those undergoing technically complex and high-risk PCI without having overt cardiogenic shock. The current article reviews the advancement in the use of various devices in both AMI complicated by cardiogenic shock and complex high-risk PCI, highlights the available hemodynamic and clinical data associated with the use of MCS devices, and presents suggestive management strategies focusing on appropriate patient selection and optimal timing and support to potentially increase the clinical benefit from utilizing these devices during PCI in this high-risk group of patients.

Place de l’assistance circulatoire dans le choc cardiogénique en France en 2018 : revue de la littérature et perspectives

Le choc cardiogénique reste de nos jours une entité mal définie, assez fréquente en pratique clinique (60 000–70 000 cas/an en Europe), dont le pronostic est sombre, avec une mortalité souvent supérieure à 40 % à 30 jours. À travers cette revue de la littérature, nous essaierons de définir cette entité et ses étiologies, avant de parler de son incidence et de son pronostic. L’approche physiopathologique du choc cardiogénique nous permettra par la suite d’approcher sa prise en charge thérapeutique classique (gestion de la volémie, amines inotropes et vasoconstrictives, ventilation) et les limites de cette dernière. Ainsi, nous aborderons les assistances circulatoires et cardiocirculatoires disponibles en France, afin de les envisager au sein d’une stratégie globale de prise en charge du patient en choc cardiogénique. Nous discuterons plus spécifiquement leurs indications ainsi que l’importance du moment d’implantation afin d’optimiser leur efficacité. Enfin, nous évoquerons les assistances actuellement en développement, mais également les nouvelles stratégies thérapeutiques qui pourraient arriver dans les prochaines années.

First successful prevention of cardiopulmonary resuscitation during high-risk percutaneous coronary intervention by use of a pulsatile left ventricular assist device: baptism of fire of the iVAC2L device: a case report

Introduction

Efforts in percutaneous coronary intervention (PCI) lead to interventional treatment of complex stenoses as an alternative to coronary bypass surgery. Nevertheless, complications during PCI can occur with sudden need for circulatory support. Circulatory support devices are helpful tools during high-risk PCI to generate additional output or maintain sufficient circulation in critical situations.

Case description

We report the case of the first successful prevention of cardiopulmonary resuscitation by use of transfemoral pulsatile ventricular assist device with up to 2l additional cardiac output during a high-risk PCI in an 80-year old man with complex stenosis and a history of ventricular fibrillation during prior coronary angiography.

Discussion

The device managed to maintain an adequate circulation during massive vasospasm and bradycardia. The iVAC2L seems to be a useful tool in high-risk PCI. Its general effect on haemodynamics and patients' outcome has to be evaluated in larger multi-centre studies.

Advancements in mechanical circulatory support for patients in acute and chronic heart failure

Cardiogenic shock (CS) continues to have high mortality and morbidity despite advances in pharmacological, mechanical, and reperfusion approaches to treatment. When CS is refractory to medical therapy, percutaneous mechanical circulatory support (MCS) should be considered. Acute MCS devices, ranging from intra-aortic balloon pumps (IABPs) to percutaneous temporary ventricular assist devices (VAD) to extracorporeal membrane oxygenation (ECMO), can aid, restore, or maintain appropriate tissue perfusion before the development of irreversible end-organ damage. Technology has improved patient survival to recovery from CS, but in patients whom cardiac recovery does not occur, acute MCS can be effectively utilized as a bridge to long-term MCS devices and/or heart transplantation. Heart transplantation has been limited by donor heart availability, leading to a greater role of left ventricular assist device (LVAD) support. In patients with biventricular failure that are ineligible for LVAD implantation, further advancements in the total artificial heart (TAH) may allow for improved survival compared to medical therapy alone. In this review, we discuss the current state of acute and durable MCS, ongoing advances in LVADs and TAH devices, improved methods of durable MCS implantation and patient selection, and future MCS developments in this dynamic field that may allow for optimization of HF treatment.