Mechanical Circulatory Support for Decompensated Heart Failure

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.

How does protocolization improve outcomes in cardiogenic shock due to end-stage heart failure?

BACKGROUND

Protocolized team-based care has been shown to improve outcomes in cardiogenic shock (CS) in patients with end-stage heart failure (ESHF). This study tested the hypothesis that protocolized care improves survival by reducing multi-organ dysfunction prior to orthotopic heart transplantation (OHT) or durable left ventricular assist device (LVAD).

METHODS

We developed a protocolized Recognize/rescue-Optimization-Stabilization-Exit/de-Escalation (ROSE) framework for CS due to ESHF. Six-month survival pre-ROSE (2014-2018) and post-ROSE (2018-2021) were compared. The Sequential Organ Failure Assessment (SOFA) score was calculated as a measure of multi-organ dysfunction pre-MCS and pre-"Exit" therapy (OHT, LVAD or recovery).

RESULTS

101 consecutive patients with CS due to ESHF who were deteriorating on inotropes (INTERMACS 1 or 2) were included (63 in Pre-ROSE and 38 in Post-ROSE). The proportions of patients who died on support (26 (41%) vs 11 (29%), p = 0.213) or bridged to "Exit" therapy were comparable between Pre- and Post-ROSE: OHT (28 (44%) vs 21 (55%), p = 0.292); durable LVAD (8 (13%) vs 5 (13%), p = 0.947); or recovery (1 (2%) vs 1 (3%), p = 0.715). SOFA score prior to "Exit" therapy was higher Pre-ROSE compared to Post-ROSE (4 (2-7) vs 2 (1-5), p = 0.012). Six-month survival from initial MCS (71% vs 41%, p = 0.004) and in patients who underwent "Exit" therapy (100% vs 71%, p = 0.001) were higher Post-ROSE vs Pre-ROSE, respectively. Higher pre-"Exit" SOFA score was associated with 6-month survival. None of the patients with Pre-"Exit" SOFA score ≥ 9 survived at 6 months.

CONCLUSION

Protocolization of CS care in ESHF improved six-month survival by improving multi-organ dysfunction (SOFA score) prior to OHT and LVAD implant.

In-Hospital Utilization and Outcomes of Palliative Care Consultation in Patients With Advanced Heart Failure Complicated by Cardiogenic Shock Requiring Mechanical Circulatory Support

Prior studies have shown that the early inclusion of palliative care (PC) specialist is associated with better end-of-life experiences. The National Inpatient Sample Database was queried from 2012 to 2017 for relevant of ICD)-9 and -10 procedural and diagnostic codes to identify patients above 18 years with advanced heart failure (HF) admitted with cardiogenic shock (CS) requiring mechanical circulatory support (MCS). Baseline characteristics, utilization trends and invasive procedures and complications were compared among patients evaluated by PC and those who were not. There were 65,230 patients hospitalized for advanced HF complicated by CS requiring MCS, of these a PC consult was placed in in 9,200 patients (14.1%) and trended upward from 9.4 to 16.8%, between 2012 to 2017. The majority of patients, (37.3%) from the total population died in hospital. In reference to patients who were discharged alive, PC consultation was associated with a lower incidence of invasive procedures such as mechanical ventilation, pacemaker implantation, defibrillator implantation, insertion of percutaneous feeding tubes and tracheostomies performed (p <0.05 for all) whereas complications such as major bleeding, septic shock, transfusion of any blood product were comparable between both cohorts (nonsignificant p value for all). On the other hand, in those patients who died in hospital PC was associated with a lower incidence of pacemaker implantation, defibrillator implantation and insertion of percutaneous feeding tubes (p <0.05 for all). Despite the high morbidity and mortality associated with advanced HF patients with CS requiring MCS, the overall prevalence of PC consultation is exceedingly low. When utilized, the incidence of invasive procedures was lower. This study highlights the underutilization of PC services in this patient population, precluding any perceived benefit in end-of-life experiences.

ECPella: Concept, Physiology and Clinical Applications

Addition of Impella on top of venoarterial extracorporeal membrane oxygenation (VA-ECMO) has gained wide interest as it might portend improved outcomes in patients with cardiogenic shock. This has been consistently reported in retrospective propensity-matched studies, case series, and meta-analyses. The pathophysiologic background is based on the mitigation of ECMO-related side effects and the additive benefit of myocardial unloading. In this perspective, thorough knowledge of these mechanisms is required to optimize the management of mechanical circulatory support with this approach and introduce best practices, as the interplay between the two devices and the implantation-explantation strategies are key for success.

Outcomes of temporary mechanical circulatory support in cardiogenic shock due to end-stage heart failure

Background

There are few reports of mechanical circulatory support (MCS) in patients with cardiogenic shock (CS) due to end-stage heart failure (ESHF). We evaluated our institutional MCS strategy and compared the outcomes of INTERMACS 1 and 2 patients with CS due to ESHF.

Methods

Retrospective analysis of prospectively collected data (November 2014 to July 2019) from a single centre. ESHF was defined by a diagnosis of HF prior to presentation with CS. Other causes of CS (eg: acute myocardial infarction) were excluded. We compared the clinical course, complications and 90-day survival of patients with CS due to ESHF in INTERMACS profile 1 and 2.

Results

We included 60 consecutive patients with CS due to ESHF Differences in baseline characteristics were consistent with the INTERMACS profiles. The duration of MCS was similar between INTERMACS 1 and 2 patients (14 (10–33) vs 15 (7–23) days, p = 0.439). There was no significant difference in the number of patients with complications that required intervention. Compared to INTERMACS 2, INTERMACS 1 patients had more organ dysfunction on support and significant lower 90-day survival (66% vs 34%, p = 0.016).

Conclusion

Our temporary MCS strategy, including earlier intervention in patients with CS due to ESHF at INTERMACS 2 was associated with less organ dysfunction and better 90-day survival compared to INTERMACS 1 patients.

Myocardial ischemia and coronary disease in heart failure

Heart failure is a complex clinical syndrome and represents the final path of numerous heart diseases. Coronary artery disease is recognized as the primary risk factor for heart failure development, being the main etiological factor in more than 50% of heart failure patients in North America and Europe. Regardless of overt coronary artery disease, myocardial ischemia is a common finding in failing hearts, likely due to structural or functional coronary circulation alterations. Ischemia is a self-propagating process which irreversibly impairs the cardiac function and negatively impacts prognosis. Thus, a better and thorough understanding of myocardial ischemia pathophysiology in heart failure would likely lead to significantly improved outcomes in these patients. This review aims to describe the mechanisms of myocardial ischemia and coronary artery disease in heart failure, focusing on coronary circulation dysfunctions due to increased parietal stress or non-obstructive coronary disease, and discussing the association and management of coronary artery disease in patients with heart failure.

Protek Duo Rapid Deployment cannulation utilized to bridge to durable heartware left ventricular assist device

A 43-year-old gentleman was transferred for management of acute on chronic cardiogenic shock (left ventricular ejection fraction < 10%). Upon arrival, we inserted a left axillary intra-aortic balloon pump for hemodynamic support. He underwent an emergent left and right-heart catheterization which showed patent stents and coronaries, in the setting of severely elevated pulmonary artery and pulmonary capillary wedge pressure. On hospital day 35, we escalated support to Centrimag in conjunction with a 31 French Protek Duo Rapid Deployment cannula. A centrimag cannula apical sewing cuff was sewn in continuous fashion along the left ventricular apex. Via modified seldinger technique, we tunneled the Protek Duo Rapid Deployment cannula through the silastic sewing cuff and the ventricular apex, traversing the aortic valve. On hospital day 50, he underwent left anterior thoracotomy and mini-sternotomy for implantation of durable Heartware left ventricular assist device. He was discharged home off inotropes and had resumed his normal activities. He is currently listed as status four for heart transplantation.

Cardiogenic Shock Due to End-Stage Heart Failure and Acute Myocardial Infarction: Characteristics and Outcome of Temporary Mechanical Circulatory Support

BACKGROUND

Mechanical circulatory support (MCS) is increasingly used in cardiogenic shock, but outcomes may differ between patients with acute myocardial infarction (AMI) or end-stage heart failure (ESHF). This study aimed to describe the characteristics of patients with cardiogenic shock due to AMI and ESHF.

METHODS

Single-center study of consecutive patients with cardiogenic shock due to AMI (n = 26) and ESHF (n = 42) who underwent MCS (extracorporeal life support, Impella or temporary ventricular assist devices). Arterial and venous O2 content and CO2 tension (PCO2), O2-hemoglobin affinity (P50) were measured. Veno-arterial difference in PCO2/arterio-venous difference in O2 content ratio was derived. Acid-base balance was characterized by the Gilfix method. MCS-related complications that required intervention or surgery were collected.

RESULTS

Patients with ESHF had lower ejection fraction, higher right and left-sided filling pressures, pulmonary artery pressure and vascular resistance, lower oxygen delivery (DO2) compared with AMI, which was not fully compensated by the increased hemoglobin P50. As a result, patients with ESHF had higher veno-arterial difference in PCO2 relative to arterio-venous difference in O2 content. Despite greater anerobic metabolism, patients with ESHF had less severe metabolic acidosis and base deficit compared with AMI, predominantly due to differences in strong ions.

CONCLUSION

The cardiogenic shock phenotype in ESHF was distinct from AMI, characterized by higher filling and pulmonary artery pressures, lower DO2, greater anaerobic metabolism but less severe metabolic acidosis.