STEMI Flashcards
Definition?
Myocardial cell death occurring due to a prolonged mismatch of perfusion and demand, resulting from a complete atherothrombotic occlusion of a coronary artery.
Risk factors?
• Smoking • Hypertension • Diabetes • Obesity • Metabolic syndrome • Physical inactivity • Dyslipidaemia • Renal insufficiency • Established CHD • Family history of CHD • Cocaine • Male Advanced age
Differentials?
- Unstable angina
- NSTEMI
- Aortic dissection
- PE
- Pneumothorax
- Pneumonia
- Pericarditis
- Myocarditis
- GORD
- Oesophageal spasm
- Costochondritis
- Anxiety
- SCAD-younger women
- Takotsubo cardiomyopathy
Epidemiology?
Age: Younger adults
Sex: Male
Ethnicity: N/A
Aetiology?
Irritation or atherosclerosis causes endothelial cell dysfunction
Clinical Presentation
- Chest pain-crushing, severe-radiates to left arm, neck, jaw
- Dyspnoea
- Pallor
- Diaphoresis
- Cardiac risk factors
- Dizziness
- Distress
- Palpitations
- N and V
Pathophysiology?
• Endothelial cells damaged by toxins become a site for atherosclerosis-fat , calcium, white blood cells, cholesterol and lipids build up
• Plaques sit in blood vessels-smaller caps with soft caps prone to breakage becomes thrombogenic and forms clots as clotting factors adhere here and release chemicals enhancing this process
• This occludes the artery,- can be LAD(anterior), RCA(back), LCX( lateral)
• Myocardial cells become hypoxemic and so begin to die after 20-40 mins and necrosis-affects inner third quicker
• ST elevation-transmural infarct-whole thickness of wall
Has to be treated quickly
1st line investigations?
Cardiorespiratory exam and history
2nd line investigations?
- ECG-ST elevation and
- ≥2.5 mm in men <40 years old
- ≥2 mm in men >40 years old
- ≥1.5 mm in women in V2-V3 and/or ≥1 mm in the other leads
- Cardiac troponin-acute MI is definitively confirmed by a rise and/or fall in cardiac troponin (withat least one value >99th percentile of the upper reference limit) in a patient who has symptoms or signs of ischaemia
- Glucose-Uncontrolled hyperglycaemia in all pts/hypoglycaemia
- FBC-anaemia/raised inflammatory markers
- Electrolytes, urea, creatinine, amd eGFR-K, Ca and Mg cause arrhythmias
- CRP-infection or inflammation
- Serum lipids-RF of hypercholesterolaemia
3rd line investigations?
- ABG-supplemental oxygen if
- arterial oxygen saturation (SaO2) <90% or
- PaO2<60 mmHg
- CXR-
- pulmonary oedema
- widened mediastinum
- cardiomegaly
- permanent pacemaker
- biventricular pacemaker
- sternal wires
- clear lung fields
- normal cardiac contour
- Transthoracic echo
- left ventricular regional wall motion abnormalities
- valvular defects
- right ventricular function
- pericardial effusion
- left ventricular mural thrombus
- cMyC-gold standard
Management pathway if <12 hrs and PCI?
- Aspirin and P2Y12 inhibitor (clopidogrel)-in IR
- Analgesia-morphine
- Anti-emetic-metoclopromide
- Oxygen-if <90%
- IV nitrate-HT,pain after GTN or CHF
- Parenteral anti-coagulation-by IR team-heparin
- Glycoprotein IB and and IIIa inhibitor-IR team-tirofiban
Management pathway if <12 hrs and no PCI?
- Aspirin and P2Y12 inhibitor (clopidogrel)-in catheter lab
- Analgesia-morphine
- Anti-emetic-metoclopromide
- Oxygen-if <90%
- IV nitrate-HT,pain after GTN or CHF
- Angiography after fibrinolysis
Management pathway if CI to fibrinolysis?
above and PCI
Management pathway if 12-48 and symptomatic?
Assess for PCI
Post-op management?
• Beta blocker/CCB • ACE inhibitor or AngII RA • Statin • DAPT Aldosterone antagonist/lipid-lowering medication
