Transcript Slide 1

ACUTE CORONARY
SYNDROME
(ACS)
ACS
Pathophysiology is that of a ruptured or
eroded atheromatous plaque.
 Acute Myocardial Infarction (AMI)

– ST-segment elevation MI (STEMI)
– Non-ST-segment elevation MI (NSTEMI)

Unstable Angina (UA)
Goals of Therapy in ACS
Reduce the amount of myocardial necrosis that
occurs in patients with MI, preserving left
ventricular function and preventing heart failure
 Prevent major adverse cardiac events: death,
nonfatal MI, and need for urgent
revascularization
 Treat acute, life threatening complications of
ACS, such as ventricular fibrillation/pulseless
ventricular tachycardia, symptomatic
bradycardias, and unstable tachycardias

Acute Coronary Syndromes Algorithm
Circulation 2005;112:IV-89-IV-110
Copyright ©2005 American Heart Association
Targeted History

Chest discomfort
– what, where, when & how much?

Associated Signs & symptoms
– dyspnea, diaphoresis, nausea

Prior cardiac history
– similar pain?
Risk Factors
 Pertinent PmHx

EKG
ST-segment elevation or presumed new LBBB is
characterized by ST-segement elevation >1mm
in 2 or more contiguous precordial leads or 2 or
more adjacent limb leads and is classsified as
ST-elevation MI
 Ischemic ST-segment depression> or = 0.5mm
or dynamic T-wave inversion with pain or
discomfort is classified as high-risk UA or
NSTEMI. Transient ST elevation of < 20 minutes
is also included within this catagory


Normal or nondiagnostic changes in ST
segment or T-waves are inconclusive and
require further risk stratification. This
includes patients with normal EKGs and
those with ST-segment deviation of <0.5
Cardiac Biomarkers

CK & CK-MB
– Rise 4-6 hours after injury
– Peak 12-24 hours after injury
– Return to baseline in 24-48 hours

Troponin – Most sensitive and specific
– Rises 4-6 hours after injury
– Peaks 18-24 hours after injury
– May take a week to return to baseline
 Longer if poor renal function
Reperfusion
Ultimate goal in ACS and immediate goal
in STEMI
 Shown to reduce mortality by 47%
 Major determinants of myocardial salvage
and long term prognosis are

– Short time to perfusion
– Complete and sustained patency of the
infarcted artery with normal flow
– Normal microvascular perfusion
Percutaneous Coronary
Intervention (PCI)
Treatment of choice if can be performed
in <90 minutes from patient presentation
 Goal should be <30 minutes from patient
presentation to either PCI, or transfer to
facility that performs PCI
 Also preferred in patients with
contraindications to fibrinolysis and is
reasonable in patients with cardiogenic
shock or heart failure.

Fibrinolysis
Indicated for STEMI if <12 hours of symptoms
and PCI unable to be performed in <90 minutes
 Goal is “door to needle” time of <30 minutes
 Absolute contraindications include: prior
intercranial hemorrhage, AVM or malignant
neoplasm, ischemic stroke>3 hour
and<3months, suspected aortic dissection,
active bleeding or bleeding diathesis, significant
closed head or facial trauma < 3months

Acute Coronary Syndromes Algorithm
Circulation 2005;112:IV-89-IV-110
Copyright ©2005 American Heart Association