Emergency Management of Acute Coronary Syndromes

Emergency Management of
Acute Coronary Syndromes

Emergency Medicine Symposium, 2015

Adam Werne, MD

Interventional Cardiology Fellow

Scope

• Coronary artery disease is the leading cause of
death in the United States.

• Acute coronary syndromes are responsible for
1.5 million U.S. hospitalizations per year.

Mozaffarian et al. Heart Disease and Stroke Statistics –
2015 Update. Circulation 131, e29-322, 2015

Pathogenesis

Amsterdam et al. 2014 AHA/ACC Guideline for the
Management of Patients With Non–ST-Elevation Acute

Coronary Syndromes. JACC 64: e139-228, 2014

Acute Coronary Syndromes (ACS)

• Unstable Angina

• Rest angina + / - Ischemic EKG changes
• New onset or rapidly progressive angina

• Non-ST-Elevation Myocardial Infarction (NSTEMI)

• Myocardial necrosis identified by troponin or CKMB

• ST-Elevation Myocardial Infarction (STEMI)

• > 2mm ST elevation in leads V2-V3
• > 1mm ST elevation in other paired EKG leads
• Potential confounders: LBBB, Pacing

Anterior STEMI

Inferior STEMI

Posterior & Lateral STEMI

Left Bundle Branch Block

Paced Rhythm

Medical Management of ACS

• Symptom improvement

• Morphine, Oxygen, and Nitroglycerin

• Platelet inhibition

• Aspirin
• Clopidogrel (Plavix) [or Ticagrelor (Brilinta), or Prasugrel (Effient)]

• Anticoagulation

• Heparin (or enoxaparin, or fondaparinux, or bivalirudin)

• Cardio-protection

• Beta blockers, ACE inhibitors, Statins

• Reperfusion

• Thrombolytics in selected STEMI patients when PCI unavailable

Percutaneous Coronary Intervention

Torpy et al. JAMA Patient Page: PCI. JAMA 291: 778, 2004

Percutaneous Coronary Intervention

42% Reduction with Primary PCI

Dalby et al. Transfer for Primary Angioplasty Versus
Immediate Thrombolysis in Acute Myocardial Infarction.

Circulation 108: 1809-14, 2033

STEMI Triage Pathway

O’Gara et al. 2013 ACCF/AHA Guideline for the
Management of ST-Elevation Myocardial Infarction.

JACC 61: e78-140, 2013

Mission Lifeline

Indiana Heart Attack Nework (IHAN)

Door-to-Balloon Time

42% mortality reduction if
PCI performed in < 90 mins

Rathore et al. Association of door-to-balloon time and
mortality in patients admitted to hospital with STEMI.

BMJ 338, 1807 (2009)

Total Ischemic Time

47% mortality reductionSymptom Onset - Reperfusion
when ischemic time is < 4 h

DeLuca et al. Symptom-Onset-to-Balloon Time and
Mortality in Patients With Acute Myocardial Infarction
Treated by Primary Angioplasty. JACC 42: 991-7, 2003

Community Outreach & Education

Improving Transfer Time: DIDO

• Only 25% of US hospitals have acute PCI capability.
• STEMI patients who present to majority of hospitals

frequently require urgent transfer for PCI.

54% mortality reduction• Delays in inter-hospital transfer cause delayed reperfusion
and can be associated with worse patient outcomes.

when DIDO time is < 30 mins• DIDO = Door In – Door Out

• Goal DIDO time = 30 minutes

Wang et al. Association of DIDO times with reperfusion
delays and outcomes among patients transferred for PPCI

JAMA 305: 2540-47, 2011

Field EKGs by EMS

• First medical contact – device time of < 120 minutes was
achieved in 96% of field transfers and only 45% of inter-
hospital transfers.

LeMay et al. A Citywide Protocol for Primary PCI in ST-
Segment Elevation Myocardial Infarction.
NEJM 358: 231-40, 2008

Field EKGs by EMS

• 39%Field EKGs Mortality Reduction

• Advanced Notification

with Field EKGs by EMS• Direct transport to PCI
• Interhospital Transfer

Nam et al. Systematic Review and Meta-analysis of the
Benefits of Out-of-Hospital 12-Lead ECG and Advance
Notification in STEMI. Ann Emerg Med 64:176-86, 2014

Cardiac Arrest

• Almost 70% of the coronary heart disease deaths in the
United States occur out of hospital, usually presenting as
“sudden death” due to cardiac arrest.

• Resuscitation is attempted by EMS in ~ 60% of cases.

• The remainder are already deceased on arrival of the EMS team

• The median survival to hospital discharge is only 7.9%

• With VF as the initial rhythm, survival is higher: ~ 22%

• Likelihood of neurologically intact survival increased by:

• Witnessed arrest with prompt bystander CPR
• Early defibrillation
• Rapid PCI for STEMI patients
• Therapeutic hypothermia for comatose patients

VF: Early CPR & Defibrillation

Valenzuela et al. Estimating Effectiveness of Cardiac
Arrest Interventions. Circulation 96: 3308-13, 1997

Therapeutic Hypothermia

25% Survival Improvement
with Hypothermia

Hypothermia after cardiac arrest study group. Mild
therapeutic hypothermia to improve the neurologic
outcome after cardiac arrest. NEJM 346: 549 –56, 2002

Patient Case: EMS in Action

• 54 yo male

• Elevated cholesterol but otherwise healthy
• Family history of coronary artery disease

• Sudden onset of chest pain while exercising

• Unrelenting heaviness, diaphoresis, arm numbness
• Sense of impending doom

• 911 call

• EMS on the scene within 10 minutes
• Vitals signs stable
• Aspirin, oxygen, and nitroglycerin administered

EMS Field EKG: STEMI

27

28

29

30

31

Summary

• ACS includes unstable angina, NSTEMI, and STEMI.

• Caused by rupture and thrombosis of atherosclerotic plaque
• Classification by cardiac biomarkers & EKG

• Goals of medical therapy include: symptoms relief, platelet
inhibition, anticoagulation, cardio-protection, & reperfusion.

• Primary PCI is the treatment of choice for STEMI.

• Goal “door-to-balloon” time < 90 minutes
• Goal “first medical contact – to – device” time < 120 minutes
• Goal DIDO time < 30 minutes
• Field EKGs by EMS improve outcomes in STEMI

• Early CPR & defibrillation are key therapies to improve
otherwise poor prognosis in cardiac arrest.