– Highlights from the 14th annual Complex Cardiovascular Therapeutics: Advanced Endovascular and Coronary Intervention Global Summit (C3), Hilton Bonnet Creek, Orlando, FL, US, 17–20 June 2018 — Focus on managing cardiac arrest.
Out-of-hospital cardiac arrest (OHCA) is the leading cause of death in Europe and the United States. Guidelines advocate immediate angiography and percutaneous coronary intervention (PCI), when indicated, in resuscitated OHCA patients with electrocardiogram (ECG) evidence of ST-elevation myocardial infarction (STEMI).1
However, the benefit of early angiography in patients with OHCA without ST-elevation on their ECG, post-resuscitation, is less clear. Several studies (including COACT [Coronary angiography after cardiac arrest],2 PEARL [Early Coronary Angiography Versus Delayed Coronary Angiography; NCT02387398], ACCESS [ACCESS to the Cardiac Cath Lab in Patients Without STEMI Resuscitated From Out-of-hospital VT/VF Cardiac Arrest; NCT03119571], TOMAHAWK [Immediate Unselected Coronary Angiography Versus Delayed Triage in Survivors of Out-of-hospital Cardiac Arrest Without ST-segment Elevation; NCT02750462], DISCO [Direct or Subacute Coronary Angiography for Out-of-hospital Cardiac Arrest; NCT02309151]) are ongoing in the investigation of early angiography and PCI in non-STEMI patients. A recent study has shown that, in these patients, 33% had a culprit vessel identified, and of this subset, 69% had an occluded vessel; overall nearly a quarter of patients with non-STEMI and OHCA had an occluded culprit vessel.3 Currently, there is support for early angiography in these patients.3 However, patients with non-shockable rhythms have worse outcomes and may not benefit as much from early angiography as patients with shockable rhythms.4,5 It was notable that up to 25% of non-STEMI, non-shockable patients still underwent PCI.5
There is an ongoing interesting question of risk of acute stent thrombosis (ST), post PCI or in patients treated with therapeutic temperature management (TTM). Primary PCI is associated with elevated ST, although this can be mitigated to some degree with prolonged bivalirudin infusion at the PCI dose, although not at reduced dose.6 There appears to be no elevated ST risk associated with TTM.7,8 Evidence was presented to support use of dual antiplatelet therapy, including P2Y12 inhibitors, in resuscitated patients with OHCA at risk of post-PCI ST. Beyond clopidogrel therapy, ticagrelor and prasugrel may offer additional benefits, and ticagrelor has been associated with a lower rate of ST compared with clopidogrel.9
The benefits of mechanical cardiopulmonary resuscitation (CPR) in the catheterisation laboratory were presented, given that prolonged cardiac arrest in this environment is not an uncommon occurrence. The first priority with CPR is to restore blood circulation for brain function – mechanical chest compressions can stabilise circulation quickly and allow for PCI and supporting interventions. It was suggested that with mechanical chest compression, post PCI, the following treatment strategies should be considered:
- if cardiac arrest resolved with return of spontaneous circulation (ROSC) and good circulation, there is no need for additive circulatory devices;
- if patient has ROSC but is in shock, consider:
- Impella device assistance10;
- extracorporeal membrane oxygenation (ECMO); and
- tandem Heart device assistance11; and
- if patient is still in cardiac arrest, initiate ECMO and consider adding an Impella device for venting the left ventricle.
Advantages of mechanical compression for the care team in the catheterisation laboratory include: less fatigue and uninterrupted chest compressions; less radiation exposure; less crowding around the table, allowing for a focus on PCI; and a better quality of chest compression, with improved depth, rate and release of compressions compared with physician CPR.
There were presentations and debate around the evolving role of the catheterisation laboratory, and a proposal for a paradigm shift in the management of OHCA. It was proposed that the cardiac catheterisation laboratory could be the primary resuscitation bay, taking advantage of highly trained teams for the rapid initiation of advanced haemodynamic support and the immediate ability to treat reversible aetiologies including coronary disease, tamponade and pulmonary embolism. The benefits of this approach were described in a study showing that 43% of patients who continued resuscitation in the catheterisation laboratory were discharged alive and with good cerebral performance, compared with 15% in a historical comparator cohort.12
Despite the benefits of treatment in the catheterisation laboratory for many patients with OHCA, there are some patients for whom this approach yields little advantage. With a view to optimised treatment and use of resources, it was suggested that patients with multiple unfavourable factors should not automatically be treated in the catheterisation laboratory. These factors for a poor prognosis include:
- unwitnessed cardiac arrest;13
- initial un-shockable rhythm;14
- no CPR from bystanders;15
- more than 30 minutes before ROSC;16
- prolonged ongoing CPR;17 and
- evidence of tissue hypoperfusion and microcirculatory failure.18
1. O’Gara PT, Kushner FG, Ascheim DD, et al. 2013 ACCF/AHA guideline for the management of ST-elevation myocardial infarction: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. 2013;127:e362–425.
2. Lemkes JS, Janssens GN, Straaten HM, et al. Coronary angiography after cardiac arrest: Rationale and design of the COACT trial. Am Heart J. 2016;180:39–45.
3. Kern KB, Lotun K, Patel N, et al. Outcomes of comatose cardiac arrest survivors with and without ST-segment elevation myocardial infarction: Importance of coronary angiography. JACC Cardiovasc Interv. 2015;8:1031–40.
4. Martínez-Losas P, Salinas P, Ferrera C, et al. Coronary angiography findings in cardiac arrest patients with non-diagnostic post-resuscitation electrocardiogram: A comparison of shockable and non-shockable initial rhythms. World J Cardiol. 2017;9:702–9.
5. Wilson M, Grossestreuer AV, Gaieski DF, et al. Incidence of coronary intervention in cardiac arrest survivors with non-shockable initial rhythms and no evidence of ST-elevation MI (STEMI). Resuscitation. 2017;113:83–6.
6. Clemmensen P, Wiberg S, Van’t Hof A, et al. Acute stent thrombosis after primary percutaneous coronary intervention: insights from the EUROMAX trial (European Ambulance Acute Coronary Syndrome Angiography). JACC Cardiovasc Interv. 2015;8:214–20.
7. Jacob M, Hassager C, Bro-Jeppesen J, et al. The effect of targeted temperature management on coagulation parameters and bleeding events after out-of-hospital cardiac arrest of presumed cardiac cause. Resuscitation. 2015;96:260–7.
8. Shah N, Chaudhary R, Mehta K, et al. Therapeutic hypothermia and stent thrombosis: A nationwide analysis. JACC Cardiovasc Interv. 2016;9:1801–11.
9. Jiménez-Britez G, Freixa X, Flores-Umanzor E, et al. Out-of-hospital cardiac arrest and stent thrombosis: Ticagrelor versus clopidogrel in patients with primary percutaneous coronary intervention under mild therapeutic hypothermia. Resuscitation. 2017;114:141–5.
10. Mukku VK, Cai Q, Gilani S, et al. Use of Impella ventricular assist device in patients with severe coronary artery disease presenting with cardiac arrest. Int J Angiol. 2012;21:163–6.
11. Kar B, Adkins LE, Civitello AB, et al. Clinical experience with the TandemHeart® percutaneous ventricular assist device. Tex Heart Inst J. 2006;33:111–5.
12. Yannopoulos D, Bartos JA, Raveendran G, et al. Coronary artery disease in patients with out-of-hospital refractory ventricular fibrillation cardiac arrest. J Am Coll Cardiol. 2017;70:1109–17.
13. Abrams HC, McNally B, Ong M, et al. A composite model of survival from out-of-hospital cardiac arrest using the Cardiac Arrest Registry to Enhance Survival (CARES). Resuscitation. 2013;84:1093–8.
14. Meaney PA, Nadkarni VM, Kern KB, et al. Rhythms and outcomes of adult in-hospital cardiac arrest. Crit Care Med. 2010;38:101–8.
15. Sasson C, Rogers MA, Dahl J, Kellermann AL. Predictors of survival from out-of-hospital cardiac arrest: a systematic review and meta-analysis. Circ Cardiovasc Qual Outcomes. 2010;3:63–81.
16. Bobrow BJ, Spaite DW, Berg RA, et al. Chest compression-only CPR by lay rescuers and survival from out-of-hospital cardiac arrest. JAMA. 2010;304:1447–54.
17. Reynolds JC, Frisch A, Rittenberger JC, Callaway CW. Duration of resuscitation efforts and functional outcome after out-of-hospital cardiac arrest: when should we change to novel therapies? Circulation. 2013;128:2488–94.
18. Stub D, Bernard S, Pellegrino V, et al. Refractory cardiac arrest treated with mechanical CPR, hypothermia, ECMO and early reperfusion (the CHEER trial). Resuscitation. 2015;86:88–94.