Clinical paperLeft-ventricular unloading in extracorporeal cardiopulmonary resuscitation due to acute myocardial infarction – A multicenter study
Introduction
In the United States more than 350,000 patients suffered from out-of-hospital (OHCA) and 209,000 patients from in-hospital cardiac arrest (IHCA) in 2016, respectively.1 Survival after cardiac arrest following conventional cardiopulmonary resuscitation (CPR) is dismal, ranging from 6 to 22%.2, 3, 4, 5, 6, 7, 8, 9 In cases in which cardiac arrest is refractory to conventional CPR (i.e., failure to obtain return of spontaneous circulation [ROSC]), the use of extracorporeal CPR (ECPR) has been shown to be associated with improved survival rates and favorable neurologic outcomes compared to conventional CPR in observational studies and recent randomised clinical trials (RCTs).2, 4, 5, 7, 8, 9 Thus, ECPR has gained wider application in selected patients with a 10-fold increase in use between 2003 and 2014, and was advocated in recent guidelines.10, 11, 12, 13 ECPR is the implementation of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in a patient still being resuscitated. Patient selection, timing of cannulation (pre-hospital versus in-hospital), methods of cannulation and survival rates vary widely across institutions.14
Although VA-ECMO allows for full circulatory support, it is inherent to increased left ventricular (LV) pressure due to retrograde aortic perfusion with increased LV afterload, which may impede myocardial recovery, aggravate pulmonary oedema and cause ventricular arrhythmias or thrombotic events. Particularly in patients with cardiac arrest due to acute myocardial infarction (AMI) and an already severely impaired LV function, increased ECMO-induced cardiac afterload may cause additional harm.15, 16, 17 Moreover, ischaemic injury can be induced by the “watershed phenomenon” once the LV starts ejecting desaturated pulmonary blood into the systemic circulation.18, 19 In order to mitigate these negative sequelae, adjunct LV unloading with an Impella® micro-axial flow pump (Abiomed, Danvers, Massachusetts, USA) may be considered to provide continuous blood flow from the LV into the ascending aorta (ECMELLA). Thus, ECMELLA use is characterised by attenuated LV preload, diminished pulmonary wedge pressure, increased cardiac output and enhanced myocardial perfusion.20 There are presently no established recommendations for LV unloading during ECPR. Thus, the decision for Impella® implantation is left to the discretion of the ECPR team based on clinical, haemodynamic, radiologic and echocardiographic parameters. Recently, it has been shown that addition of Impella® to VA-ECMO may be associated with improved survival in patients with cardiogenic shock.21, 22, 23, 24, 25, 26 Additionally, ECMELLA use has recently been shown to reduce mortality in 18 patients with cardiac arrest of any cause.27 However, to the best of our knowledge, there are no data whether ECMELLA, being utilised as part of ECPR, is associated with survival benefits in selected patients with therapy-refractory cardiac arrest caused by AMI.
Therefore, the primary aim of this study was to evaluate the 30-day mortality rate of patients with therapy-refractory cardiac arrest due to AMI being treated either with VA-ECMO alone or with ECMELLA at three tertiary care centers over five years. Secondary endpoints included intensive care unit (ICU) and hospital length of stay (LOS), LV ejection fraction (LVEF) and post-procedural complications.
Section snippets
Study population
This study was performed at three tertiary care centers of the Charité – University Hospital in Berlin, Germany, and approved by the Institutional Review Board (protocol number: EA4/220/21). The publication adheres to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines (STROBE). The analyses were carried out within a consecutively enrolled cohort of adult patients who received treatment with ECPR after a therapy-refractory cardiac arrest (i.e., no ROSC at arrival
Patient characteristics
Between 2016 and 2021, 130 patients received ECPR treatment with VA-ECMO or ECMELLA, of which 95 met the inclusion criteria of the present study. A total of 57 (60%) patients received treatment with ECMELLA while 38 (40%) received treatment with VA-ECMO (Fig. 1, Table 1, Table 2). The Impella® therapy was started 95.7 minutes [IQR 43.6–185.7] after initiation of VA-ECMO therapy.
In the unmatched cohort, the average age in both treatment groups was 63.6 (±11.4) years with 78 (82.1%) patients
Discussion
In this multicenter cohort study among selected patients who received ECPR due to therapy-refractory cardiac arrest caused by AMI, ECMELLA treatment was associated with an improved survival compared to VA-ECMO therapy alone in both unmatched and PS-matched cohorts. The results remained robust in multiple sensitivity analyses. To the best of our knowledge, this is the first study showing that ECMELLA treatment was associated with improved survival after therapy-refractory cardiac arrest caused
Conclusions
In conclusion, in this PS-matched cohort of patients with ECPR during therapy-refractory cardiac arrest caused by AMI, we report that treatment with ECMELLA was associated with improved patient outcomes compared to VA-ECMO alone. Our data support current guideline recommendations on early evaluation of ECPR in well selected patients with therapy-refractory cardiac arrest. While there are several ongoing RCTs in the field of ECPR,43, 44, 45 a RCT is urgently needed to further evaluate the role
Sources of Funding
None.
Disclosures
None.
CRediT authorship contribution statement
Tharusan Thevathasan: Conceptualization, Methodology, Validation, Formal analysis, Investigation, Resources, Writing – original draft, Visualization, Supervision, Project administration. Megan A. Kenny: Methodology, Validation, Formal analysis, Investigation, Writing – original draft, Visualization. Finn J. Krause: Validation, Formal analysis, Writing – original draft, Visualization. Julia Paul: Validation, Formal analysis, Writing – original draft, Visualization. Thomas Wurster:
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgements
None.
References (45)
- et al.
Extracorporeal life support and survival after out-of-hospital cardiac arrest in a nationwide registry: A propensity score-matched analysis
Resuscitation
(2016) - et al.
Coronary Artery Disease in Patients With Out-of-Hospital Refractory Ventricular Fibrillation Cardiac Arrest
J Am Coll Cardiol
(2017) - et al.
Advanced reperfusion strategies for patients with out-of-hospital cardiac arrest and refractory ventricular fibrillation (ARREST): a phase 2, single centre, open-label, randomised controlled trial
Lancet
(2020) - et al.
Cardiopulmonary resuscitation with assisted extracorporeal life-support versus conventional cardiopulmonary resuscitation in adults with in-hospital cardiac arrest: an observational study and propensity analysis
Lancet (London, England)
(2008) - et al.
Two-year survival and neurological outcome of in-hospital cardiac arrest patients rescued by extracorporeal cardiopulmonary resuscitation
Int J Cardiol
(2013) - et al.
ECMO Cardio-Pulmonary Resuscitation (ECPR), trends in survival from an international multicentre cohort study over 12-years
Resuscitation
(2017) - et al.
European Resuscitation Council Guidelines 2021: Epidemiology of cardiac arrest in Europe
Resuscitation
(2021) - et al.
Left Ventricular Unloading During Extracorporeal Membrane Oxygenation in Patients With Cardiogenic Shock
J Am Coll Cardiol
(2019) - et al.
Unloading of the Left Ventricle During Venoarterial Extracorporeal Membrane Oxygenation Therapy in Cardiogenic Shock
JACC Hear Fail
(2018) - et al.
European Resuscitation Council Guidelines 2021: Adult advanced life support
Resuscitation
(2021)
Left Ventricular Unloading Before Reperfusion Promotes Functional Recovery After Acute Myocardial Infarction
J Am Coll Cardiol
Transvalvular Ventricular Unloading Before Reperfusion in Acute Myocardial Infarction
J Am Coll Cardiol
Hemodynamics of Mechanical Circulatory Support
J Am Coll Cardiol
Left Ventricular Unloading Before Reperfusion Promotes Functional Recovery After Acute Myocardial Infarction
J Am Coll Cardiol
Early initiation of extracorporeal life support in refractory out-of-hospital cardiac arrest: Design and rationale of the INCEPTION trial
Am Heart J
A pragmatic parallel group implementation study of a prehospital-activated ECPR protocol for refractory out-of-hospital cardiac arrest
Resuscitation
Sub30: Protocol for the Sub30 feasibility study of a pre-hospital Extracorporeal membrane oxygenation (ECMO) capable advanced resuscitation team at achieving blood flow within 30 min in patients with refractory out-of-hospital cardiac arrest
Resusc Plus
Heart disease and stroke statistics–2015 update: a report from the American Heart Association
Circulation
Extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest: a registry study
Eur Heart J
Extracorporeal life support during cardiac arrest and cardiogenic shock: a systematic review and meta-analysis
Intensive Care Med
2019 American Heart Association Focused Update on Advanced Cardiovascular Life Support: Use of Advanced Airways, Vasopressors, and Extracorporeal Cardiopulmonary Resuscitation During Cardiac Arrest: An Update to the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care
Circulation
Cited by (8)
Left ventricular unloading during VA-ECMO: A Gordian knot of physiology
2024, ResuscitationRecognizing patients as candidates for temporary mechanical circulatory support along the spectrum of cardiogenic shock
2023, European Heart Journal, Supplement
- 1
Made equal contributions.