General Cardio Flashcards
Indications for Transvenous pacing?
Symptomatic arrhythmia with cardiovascular compromise + pharmacotherapy has failed + transcutaneous pacing has failed or contraindicated
Contraindications to transvenous pacing?
All relative
- Appropriate site CVC contraindications present
- Prosthetic tricuspid valve
- Severe hypothermia causing arrhythmia (unlikely to succeed, likely to cause VF)
Arrhythmias requiring pacing?
All are + cardiovascular compromise
- Sick sinus syndrome
- Sinus arrest
- Symptomatic sinus bradycardia
- AF with slow vent response
- 3rd degree heart block
- 2nd degree block Mobitz II
What are the best sites for transvenous pacing in order?
1- R) IJ
2- L) subclavian
3- LIJ + R) subclavian
4- any other site
What are reasonable initial settings for transvenous pacing?
Rate 70-80
Current 15-20mA
Sensitivity 1-2V
What are reasonable initial settings for transcutaneous pacing?
Rate 70-80 or 20 above intrinsic
Current 70mA
Once capture turn current down to 5-10 above threshold
If no capture at current up to 130 then resite electrodes
How should defibrillation be performed in conscious VT?
If QRS and T waves are distinguishable then an attempt at synchronisation should be done
Synchronised shock biphasic 100-200J
Unsynchronised shock biphasic 200j
Unsynchronised monophasic 360j
What are some of the causes of cardiac sounding syncope in a patient who is now stable?
Severe aortic stenosis
ARVD
WPW +/- AF
Brugada syndrome
Long Qt with TdP
High grade heart block (although usually still asymptomatic)
Short Qt syndrome
HOCM
VT (ie ischaemic cardiomyopathy)
What are some relatively benign causes of syncope that can be managed as an outpatient?
Cough syncope
Micturition syncope
Vasovagal syncope
Orthostatic hypotension (autonomic dysfunction, drugs, dehydration)
What are the routine medical treatments for a STEMI?
- Aspirin 300mg
- Nitrates (S/L, patch, infusion) as long as BP can take it
- Clopidogrel/Ticagrelor/Prasugrel
- Analgesia (Morphine, fent etc)
- Aim sats >94% (02 only if needed)
- Heparin infusion/bolus prior to PCI
When should fibrinolysis be done over PCI?
- > 120 mins from first contact to availability of PCI (aim <90mins from ED arrival to cath lab)
- Ischaemic symptoms present for less than 12hrs
- No contraindications to fibrinolysis
What are the potential causes for an acute bradycardia?
Acute ischaemia
Chronic cardiomyopathy
Drug overdose
Hypothermia
Hypoxia
Hypothyroidism
Electrolyte disturbance (Hyper K)
Raised ICP
Inflammatory/infiltrative (Sarcoid, SLE, TB, amyloid)
Typhoid fever (relative bradycardia)
Vagal stimuli
Normal variant
In those without access to immediate PCI, what are the indications for thrombolysis?
- ECG meets STEMI criteria for >20mins
- Chest pain >20mins within the last 12hrs (may have resolved)
- No contraindication to thrombolysis
What are the high and low risk features for someone with chest pain having ACS?
What are some of the causes of a troponin rise other than ACS?
What are the principle causes of a dilated cardiomyopathy?
What are the main drugs causing dilated cardiomyopathy?
Clozapine
Phenothiazines
Chloroquine
Antiretroviral
- Zidovudine, Zalcitabine
Chemotherapeutics
- Cyclophosphamide, Anthracyclines, Trastuzumab
What are statistics of syncope ED presentations?
- 1-1.5% of all ED presentations
- Approx 20% of people will have an episode in their lifetime
- 35% of patients presenting to ED with syncope go on to be admitted
- Men have higher risk of arrhythmias
What are the typical clinical and historical features of burgada syndrome?
- Autosomal dominant
- 2 year death rate after 1st ED presentation if not treated is 30%
- SE asian descent is risk factor
- Na+ channel defect
- Average age at presentation 30yo
- Causes 60% idiopathic VF
- Avoid Na+ channel blockers including class 1a and 1c
What are the clinical features of silent AMI’s?
- Twice the mortality of those presenting with chest pain
- Higher risk in females, diabetics, CCF previous stroke and the elderly
- 1% per annum for people aged 45-65
What is the Framingham Criteria for CCF?
At least 2 major or 1major and 2 minor critiera
Major
- PND/Orthopnoea
- Raised JVP
- APO
- Cardiomegaly on CXR
- S3 gallop
Minor
- Ankle oedema
- Nocturnal cough
- tachycardia >120
- SOB on exertion
- pleural effusions
What are the indications for overdrive pacing?
Any regular tachycardia with a re-entrant circuit, as it short circuits the re-entrant circuit
- Ie SVT, VT, A flutter
- Also to prevent TdP in patients with prolonged QTc and relative bradycardia
Does not work on VF/AF
How is overdrive pacing performed to terminate regular tachyarrythmias ?
Accelerate to about 10-15% greater rate than the intrinsic rate for 8-10secs then cease
Requires transvenous (temporary or permanent) pacing, transcutaneous cannot fire fast enough
What are the factors favouring a rhythm controlled approach to AF?
- Haemodynamically unstable
- Young
- First presentation
- Onset <24hrs
- No structural/valvular HD
- No/corrected precipitant cause
- Normal/corrected electrolytes
- Normal TFT’s
- Intolerable symptoms
What are the factors favouring rate control in AF?
- Age >80 yrs
- Low HASBLED score
- Failure of rhythm control
- Minimal to no symptoms
- Haemodynamically stable
- Patient preference
- Structural/valvular heart disease
- Long term AF
- Underlying precipitant has not/can not be fixed
- intolerable side effects from pharmacological rhythm control
What are the goals of management in AF?
- Reverse haemodynamic instability
- Prevent thromboembolism
- Alleviation of symptoms
- Reduce CVS disease and mortality
- Prevent adverse cardiac remodelling
What is the ADAPT protocol for chest pain rule out?
TIMI score
+
2 -ve troponins
+
no ischaemic changes on ECG
= discharge
What is the TIMI score for chest pain?
Used for risk stratification in chest pain, but originally derived from unstable angina/NSTEMI patients 30 day mortality
- Age >65
- 3 or more CAD risk factors
- Known CAD 50% or more
- Aspirin use in last 7 days
- Symptoms typical of severe angina >2 episodes in 24hrs
- ECG ST changes >0.5mm
- Positive cardiac marker
What is the HEART score for chest pain?
Used in adult chest pain patients being considered for ACS workup
- Divides into risk categories based on likelihood of major adverse cardiac events (MACE)
H- History (slightly, moderate, very suspicious) 0-2 points
E- ECG (normal, non-specific, sepcific ST changes) 0-2
A- <45, 45-65, >65, 0-2 points
R- Risk factors (0, 1-2, 3 or more) 0-2
T- Troponin (normal, 1-3x limit, >3x limit) 0-2 points
Low score
- 0-3 points, <0.3% risk MACE
Moderate score
- 4-6 points, 12-16% MACE
- High 7 or more, 50-65% MACE
