Myocardial Infarction Flashcards
(19 cards)
MI
Definition
Evidence of myocardial ischemia on the spectrum of ACS (unstable
angina, NSTEMI and STEMI)
Diagnosed by cardiac marker abnormalities and one
of: ECG changes or HPI consistent with ACS.
MI
Differential Diagnosis
Stable Angina
Transient episodic chest discomfort secondary to myocardial ischemia
Precipitated by exertion or emotion, lasts <15 mins, relieved by rest or nitro
MI
Differential Diagnosis
Unstable Angina
Angina with minimal exertion or at rest New-onset angina
Angina post
MI/PCI/CABG
Worsening change from baseline angina
Increased duration of pain or
threshold
Decreased response of previously effective angina meds
MI
Differential Diagnosis
NSTEMI (Non Occlusive)
Infarction without ST elevation (note: 25% NSTEMI have totally occluded artery)
MI
Differential Diagnosis
STEMI
Infarction with primary ST elevation: ≥1mm in 2 contiguous leads, except for
V2-3 ≥1.5mm in females, ≥2mm in males over 40, and ≥2.5 in males under 40 –
Other signs of occlusion: hyperacute T waves, minor ST elevation with
reciprocal ST depression,
Posterior MI (primary ST depression V1-4, often with0.5mm STE on posterior leads)
LBBB + Modified Sgarbossa, DeWinter sign
MI
Assessment
History
character of pain, associated symptoms (diaphoresis, radiating pain,
vomiting, and exertional pain have highest likelihood ratios for acute MI)
MI
Assessment
Classic Risk Factors
male, smoking, diabetes, HTN, FHx, dyslipidemia
MI
Assessment
Varied Presentations
women, elderly, diabetics, dementia
MI
Assessment
Complications of AMI
arrhythmias, cardiogenic shock, papillary muscle rupture,
pericarditis, stroke
MI
Assessment
Physical Exam
vitals, cardiac exam, resp exam, pulses, signs of complications
MI
Management
General
General
ABCs, monitors, oxygen, vitals, IV access
MI
Management
Pain control
Pain control: NTG (avoid for RV infarcts) or Morphine if resistant to NTG
MI
Management
ACEi, β-blockers, Statins
ACEi, β-blockers, Statins
Atorvastatin 80mg PO in STEMI. Do
NOT delay transfer to cath lab for
statin
No role for initiating ACEi or β-blocker
in the ED
ACEi, β-blocker + statins likely to be
initiated during hospital admission (.
<24-48 hrs from time of presentation)
MI
Management
Antiplatelet Therapy
Antiplatelet Therapy
ASA 325mg chewed
Clopidogrel 300mg PO OR Ticagrelor
180mg PO (if going for primary PCI)
MI
Management
Antithrombotic Therapy
Antithrombotic Therapy
Primary PCI: UFH 4000 Units (max)
then 12 U/kg/hr
MI
Management
Fibrinolytics
Fibrinolytics: Enoxaparin or
Fondaparinux IV bolus then SC dose
daily
MI
Management
Goals
Goals
Primary PCI: within 90 mins of
hospital arrival
Lytics: <12 hours of symptoms or
cannot get to PCI centre within 120
mins, given within 30 mins of
hospital arrival
MI
Investigations
ECG (ST-T changes, new BBB, pathological Q waves), CXR
Labs: CBC, lytes, cardiac enzymes
MI
Investigations
Labs
CBC, lytes, cardiac enzymes
