MI/ACS Flashcards
Fixed RFs for ACS
Age
Gender
FMx (genetics)
Most common cause of stable angina
Atheroma
What is stable angina?
Clinical manifestation of ischaemia due to obstructed blood flow. Pain is relieved after <5mins when resting
‘Induced by effort and relieved by rest’
What else, besides exercise, can bring on symptoms of angina?
Mental and emotional stress Sexual activity Tachycardia from any source Anxiety Fever
Primary prevention of angina
Reduce any RFs related to IHD
Maintain an idea blood pressure (<140/80)
Secondary prevention of angina
Patient education RE healthy lifestyle
Antiplatelet therapy indefinitely
Investigations to consider in Angina with rationale
ECG - may be normal between attacks but may show ST depression during an attack. This is indicative of ischaemia
Hb - anaemia means the heart has to work harder which may exacerbate angina or cause it without coronary obstruction
Fasting lipid profile - Elevated LDL = increased risk
Typical angina symptoms
Pain brought on by exercise or stress
Relived by rest or GTN
Anterior chest ‘squeezing’
Pt with diagnosis of angina is not able to tolerate her B-blocker. What can you prescribe?
Calcium Channel Blocker
When would a long acting nitrate be prescribed in angina?
When the pt cannot tolerate BB or CCB
What should be done if the pt is still symptomatic after LAN, BB and CCB?
Consider revasc. w/ PCI or CABG depending on pt
Differentiating factor between angina and unstable angina
UA involves prolonged (>20mins) pain at rest, angina of increasing freq. or that occurs after a recent MI
Most common cause of UA
Coronary artery narrowing due to thrombus development on a disrupted atherosclerotic plaque
Difference between NSTEMI and UA
NSTEMI involves occluding thrombus which leads to myocardial necrosis and increase in cardiac enzymes
Primary prevention of CAD
Lifestyle changes
Statin therapy
Antiplatelet therapy
Presentation of unstable angina
Positive RFs in history Increasing severity of CP Increasing freq. of CP Dyspnoea S4 heard (indicates reduced myocardial relaxation due to ischemia)
Investigations to order in UA plus rationale
ECG - obtained and analysed within 10 mins of CP presentation. May be normal or have transient ST depression or T wave inversion. If the ECG is not diagnostic but the pt remains symptomatic then think ACS
Troponin assay - Excludes MI if not elevated
FBC (Hb) - Check for anaemia
BM - Should be normal but if elevated then an assessment for diabetes is reqd.
U+Es - Should be normal. Reqd to establish predictor for mortality
Lipid profile - recommended for risk stratification
Coagulation profile - to establish baseline results as some treatment may affect the coag
CXR - to exclude mediastinal changes
UA DDx
Stable Angina
STEMI
NSTEMI
Heart Failure
Management of Unstable Angina
Low risk:
Aspirin + Clopidogrel + Analgesia + B-Blocker + lifestyle changes
Stabilised high risk:
Manage with angiography + lifestyle changes + anti platelet therapy + ACEi +
Clinical presentation of an MI
Severe crushing CP > 20 mins No relief w/ GTN or rest CP radiate to neck, jaw and arm Dyspnoea, fatigue, syncope Px is pale and clammy Thready pulse Vomiting
Which group of patients must be closely monitored in MI history taking?
Diabetics due to silent MIs
Which other conditions can cause ST elevation?
ELAVATION
Electrolyte abnormalities
Left bundle branch block
Aneurysm of left ventricle
Ventricular hypertrophy
Arrhythmia disease (Brugada syndrome, ventricular tachycardia)
Takotsubo/Treatment (iatrogenic pericarditis)
Injury (myocardial infarction or cardiac contusion)
Osborne waves (hypothermia or hypocalcemia)
Non-atherosclerotic (vasospasm or Prinzmetal’s angina)
ECG findings weeks after an MI
Presence of Q wave
T wave inversion sometimes
T wave flattening
Bloods to order in MI
Serum lipids
Glucose
UEs
Cariac Biomarkers
DDx in MI
UA NSTEMI AAA PE Pneumothorax Pneumonia GORD Anxiety
Management in suspected MI
Aspirin + O2
Analgesia
GTN
Management of unstable MI
Emergency revasc. Anticoagulation (abciximab + enox./hep) Aspirin Analgesia O2 Glucose control Inotrope
Subsequent management of stable post MI pt
Aspirin Beta Blocker ACEi Statin Lifestyle changes
Which vessel and aspect of the heart is affected if there are ST elevations in leads II,III and aVF?
Right Coronary Artery and Inferior aspect
Which vessel and aspect of the heart is affected if there are ST elevations in leads I, aVL, V5+6?
Left circumflex and anterolateral aspect
Which leads represent the LAD and anteroseptal aspect of the heart?
V2-4
Which leads and aspect do V2-6 represent?
Anterior aspect and left main stem
Which leads represent the posterior aspect + RCA
V1/2/3
Lead placement in ECG
V1: 4th ICS RSE 2: 4TH ICS LSE 3: Midway V2-4 4: 5th ICS MCL 5: Midway V4-6 6: 5th ICS MAL R: R WRIST Y: L WRIST G: L ANKLE B: R ANKLE
Indication of absent P waves
AF
SAN block
Indication of biphasic P waves / peaked P waves
Left Atrial Hypertrophy / Right atrium Hypertrophy
What is the indication of deep ST waves in leads 1-3
True Posterior MI
Rememebr the posterior leads are on the back so the ECG is inverted but it’s still an ST rise