Ischaemic Heart Disease Flashcards
What disease accounted for the most deaths in Australia according to the 2007-8 National Health Survey?
Coronary heart disease (CHD)
Describe the epidemiology of coronary heart disease
3% of the Australian population have CHD
Incidence increases with age
Prevalence higher in males
CHD mortality on the decline (has halved between 1987 and 2007, attributed to reduced smoking and improved care)
List the 8 key cardiac risk factors
Age
FHx of IHD
Obesity
Sedentary lifestyle
Smoking Hx
Hypercholesterolaemia
HTN
DM
What are 5 common symptoms of IHD?
Ischaemic chest pain
SOB
Palpitations
Syncope
Lethargy
Distinguish between stable and unstable angina
Stable: comes on with exercise/cold/stress, relieved by rest, no recent change, relieved with GTN
Unstable: new onset pain pain at rest or pain at lower levels of exercise, not relieved by GTN
NB MI is also characterised by pain at rest and is not relieved by GTN
What is the WHO definition of an AMI?
At least 2 of the following features:
Symptoms of MI
Elevation of cardiac markers (troponin or CK)
Typical ECG pattern (Q waves, ST segment changes or T wave changes)
Define acute coronary syndrome (ACS)
Acute narrowing or occlusion of a coronary artery resulting in ischaemic pain
What is the typical pathophysiology of an ACS?
Coronary thrombosis in association with a ruptured atherosclerotic plaque
How might an ACS present clinically?
STEMI/NSTEMI
Unstable angina
SCD
64 year old woman with 1/24 typical chest pain, SOB and diaphoresis
Cardiac RFs: HTN, hypercholesterolaemia
Rx: perindopril, atorvastatin
Haemodynamically stable (HR 70 bpm, BP 165/90 mmHg)
O/E unremarkable
What are the key diagnostic features of this ECG?
Inferior ST elevation with reciprocal anterolateral ST depression
What is the management of choice for MI in the acute setting? What are the limitations of this management?
Reperfusion therapy (PCI or fibrinolysis)
Must be administered within 4 hours of symptom onset for optimal outcome
What options are available for reperfusion therapy?
Percutaneous intervention (PCI; generally preferred) Fibrinolysis
When is PCI preferred over fibrinolysis?
Skilled lab available
Door to balloon time <60 mins
High-risk patients
CI to fibrinolysis
Late presentation
Dx of STEMI in doubt
When is fibrinolysis preferred over PCI?
Early presentation
Invasive strategy not an option
Delay to invasive option
What adjunctive therapies are used in the management of AMI?
Oxygen
IV morphine
Aspirin
IV heparin or SC clexane
IV GTN
Additional antiplatelet agents if stent inserted
Evidence for B-blockers and ACEIs post-AMI (MONASH)
What is the significance of a small CK rise on future prognosis?
Indicates an improved long-term prognosis with minimal functional impairment of the myocardium (provides an indication of myocardial damage)
What is the critical time-dependent goal of reperfusion therapy? What is the time-independent goal?
Time-dependent: myocardial salvage (best within 4 hours)
Time-independent: open the infarct-related artery
What is the evidence for B-blockers and ACEIs after an AMI?
B-blockers reduce morbidity and mortality post-AMI; they reduce angina, arrhythmias and rates of recurrent AMI, and improve LV function
ACEIs may improve LV EF and reduce mortality
What discharge medications should a patient be sent home on post-AMI?
B blocker
ACEI
Statin
Aspirin
Clopidogrel (9/12; + 3/12 warfarin if high risk)
GTN
64 year old male admitted with 8/24 chest discomfort, epigastric pain and SOB
Cardiac RFs: ex-smoker, HTN
PHx: heavy alcohol use
Rx: atenolol
Haemodynamically stable (HR 90 bpm, BP 145/80 mmHg)
O/E: mild LV failure with S3 and bibasal inspiratory creps
What are the key diagnostic features of the presenting ECG?
ST depression in leads V5 and V6
T wave changes in leads V2-V4
OM1
1st obtuse marginal
Post-stenting for NSTEMI, patient continued to have persistent SOB but no further chest pain
CK peak: 952 U/L
ECG: resolution of lateral ST depression
Echo: moderate-severe impairment of LV function with lateral wall akinesis, anterior and inferior wall hypokinesis
What are the key features on this CXR? What is the likely clinical course of this patient’s presentation and what does this mean for Mx?
Alveolar oedema (“batwings” appearance)
Kerley B lines (interstitial oedema)
Cardiomegaly
Dilated prominent upper lobe vessels
Effusion (pulmonary)
Likely ischaemic insult (NSTEMI) occurred on background of prior LV dysfunction; anti-ischaemic and HF therapy should be optimised
Discharge Rx for patient with NSTEMI on background of prior LV dysfunction (i.e. anti-ischaemic and HF therapy)
ACEI
B-blocker
Diruetic (e.g. loop diuretic and K+ sparing; may also require slow K)
Thiamine (because of effects of alcohol or diuretic)
Statin
Aspirin
Clopidogrel (9/12 + 3/12 warfarin if high risk)
What are the broad categories of possible complications of AMI?
Ischaemic
Mechanical
Arrhythmic
Embolic
Inflammatory
(AMI Emergency Indication)
