Concepts to Remember Flashcards
What is the normal PR interval?
120 - 200 mS
(0.12 - 0.20 seconds)
3-5 small squares
What is the normal QRS complex time?
<120 mS
< 0.12 seconds
Formula for BP?
BP = CO x PR
Formula for CO?
CO = SV x HR
Formula for SV?
EDV - ESV
Formula for Ejection Fraction?
SV/EDV
There are normally 2 heart sounds (S1 and S2). What does S3, an additional heart sound, represent?
increased filling pressure due to ventricular dilation
There are normally 2 heart sounds (S1 and S2). What does S4, an additional heart sound, represent?
high atrial pressure due to ventricular hypertrophy (non-compliance)
What is papilloedema?
is optic disc swelling that is caused by increased intracranial pressure due to any cause
What is the definition of cardiac output?
amount of blood your heart pumps out each minute
What occurs to the blood pressure in vasoconstriction?
BP increases
What occurs to the blood pressure in vasodilation?
BP decreases
What is a parasternal heave normally caused by?
right ventricular hypertrophy
What does the T wave represent?
repolarisation of the ventricles
What does the U wave present?
repolarisation of the purkinje fibres
What is the of the 2 hypertrophy voltage criteria?
hypertrophy will lead to an increased amount of muscle which will lead to more electrical activity present
What is the neurotransmitter of the sympathetic nervous system?
norepinephrine
What is the neurotransmitter of the parasympathetic nervous system?
acetylcholine
What is another term for a sympathomimetic?
adrenergic agonist
What is another term for a sympatholytic?
adrenergic antagonist
What is another term for a parasymapthomimetic?
muscarinic agonist
What is another term for parasympatholytic?
muscarinic antagonist
What is the function of alpha 1 receptors?
vasoconstriction, contraction + urinary retention
What is the function of beta 1 receptors?
increase heart rate, increase contractility, increase conduction in heart
What is the function of beta 2 receptors?
vasodilation + bronchodilation
Give 2 examples of non-selective alpha receptor antagonists and why they may not be used anymore
- Phenoxybenzamide
- Phentolamine
not used b/c they increase cardiac output + induce tachycardia, dysrhythmias and increased GIT activity
List the uses of beta receptor antagonists
- arrhythmias
- angina, MIs
- cardioprotective (after an MI)
What is a cardioselective beta blocker?
beta1 receptor antagonist
List 3 side effects of atenolol
- cold extremities
- insomnia
- depression
What is the MOA of M1, M3, and M5 receptors?
- increase cellular excitability
- act via the inositol phosphate pathway
- essentially increasing calcium
What is the MOA of M2 and M4 receptors?
- decrease cellular excitability
- inhibit adenylate cyclase
- essentially decreasing calcium
What is myasthenic crisis?
Myasthenia gravis may cause respiratory failure (due to exhaustion of the respiratory muscles)
What test is used to diagnose myasthenia gravis?
Edrophonium Test
List some of the effects of augmenting the parasympathetic system (i.e. cholinergic agonists)
- hypotension
- bradycardia
- bronchoconstriction
- increased secretions
- GIT hypermotility
- decreased intraocular pressure
List the 4 muscarinic receptor antagonists (cholinergic receptor antagonists)
- Atropine
- Ipratropium (M3-selective)
- Darifenacin (M3-selective)
- Pirenzepine (M1-selective)
Botulin Toxin (Botox) is a indirectly-acting cholinergic receptor ANTAGONIST. List some of the SIDE EFFECTs of botox
- progressive parasympathetic + motor paralysis
- dry mouth
- blurred vision
- difficulty in swallowing
- respiratory paralysis
What is a side effect of broad spectrum cholinergic receptor agonists?
potentiates all nicotinic and muscarinic actions
What is a side effect of broad spectrum cholinergic receptor antagonists?
- results in loss of all autonomic function
- impair voluntary movement
What is another term for HMG-CoA Reductase Inhibitors?
Statins
List the first-line treatment and other treatment options for dyslipidaemia
First Line Treatment: Statins
- Bile Acid Binding Resins/Sequestrants
- Fibrates
- Nicotinic Acid
What is the most common drug a/w statin-induced myopathy?
Gemfibrozil
List drugs that are a/w statin-induced myopathy
- Gemfibrozil (most common)
- Macrolide antibiotics
- Azole antifungals
- Cyclosporine
- HIV protease inhibitors
- Amiodarone
Statin-induced myopathy can be caused by drugs that interfere with which enzyme?
CYP3A4 (involved in statin oxidation)
List 2 possible ECG changes of a STEMI
- ST Elevation
2. New LBBB
List 2 possible ECG changes of a NSTEMI
- ST Depression
2. T Wave Inversions
What disorder can cause psychogenic pseudo-syncope?
Somatization Disorder
What investigation is typically always done when investigating syncope?
12 Lead ECG
List 2 possible treatments for heart block management. (be specific)
- Medications
a) Atropine
b) Dopamine
c) Dobutamine - Pacing (for complete AV block or symptomatic 2nd degree block)
What is the purpose of CHADS2VASc score?
rating the risk of thromboembolism + stroke in NON-VALVULAR atrial fibrillation
What anti-thrombotic drug(s) should be given to someone with NON-VALVULAR atrial fibrillation?
- warfarin
OR - direct oral anticoagulants (DOACs)
What anti-thrombotic drug(s) should be given to someone with VALVULAR atrial fibrillation?
- ONLY warfarin
- do NOT given DOACs
What is the ABC treatment in atrial fibrillation?
A - Anticoagulation/Anti-thrombotic therapies
- warfarin/DOACs
B - Better Symptom Control (either rate* or rhythm)
- i) Beta Blockers*
- ii) Calcium Channel Blockers*
- iii) Digoxin
- iv) Amiodarone (last resort)
C - Cardiovascular risk factors
How long should the QT interval be in males and females?
Males: < 450 mS/0.45 seconds
Females: < 470 mS/0.47 seconds
What is the normal ejection fraction of the heart?
b/w 50 - 70%
Why can those with hypertrophic cardiomyopathy have angina?
because increased muscle requires more oxygen (supply does not satisfy the demand)
Hypertrophic Cardiomyopathy is mainly caused by inefficiency of what?
inefficiency of ATP utilization
- triggers Ca2+ dependent hypertrophy
What proteins (gene mutations) are mainly a/w hypertrophic cardiomyopathy?
sarcomeric proteins
What is the most common arrhythmia?
Atrial Fibrillation
What is Jervell Lange-Nielson disease and what does it cause?
- autosomal recessive
- causes Long QT syndrome
- a/w deafness
What is Romano-Ward disease and what does it cause?
- autosomal dominant
- causes Long QT syndrome
List 3 possible treatments for Long QT syndrome
- Beta Blockers
- Left Cardiac Sympathetic Denervation
- Implantable Cardiac Defibrillator (ICD)
What is Brugada Syndrome? How can it be treated?
- autosomal dominant
- structurally normal heart
- but ST segment elevation in right heart leads
- SUSCEPTIBLE TO V. TACH
treat w/ implantable cardiac defibrillator (ICD)
What is the Vaughan Williams Classification?
used to classify different anti-arrhythmic drugs
List the SIRS/Sepsis Criteria. If 2 or more criteria are present, this means that SIRS is present
- Temperature (>38 OR <36)
- Heart Rate > 90 bpm
- Respiratory Rate > 20
- WBC (>12 000 OR <4 000)
+ suspected/present infection (to turn it into sepsis)
Bernard-Souilier Syndrome is a platelet disorder. What is defective?
defective GPIb receptor
Grey Platelet Syndrome is a platelet disorder. What is defective?
defective granule secretion
Glazmann Thrombasthenia is a platelet disorder. What is defective?
defective GPIIb/IIIa receptor
What is the main risk for anti-platelet therapies?
Bleeding
List some contraindications to aspirin (an anti-platelet therapy)
- allergic to ibuprofen
- NSAID precipitated bronchospasm
- kidney disease
- peptic ulcers
- gastritis
- patients w/ bleeding risks
List 3 complications of Implantable Cardioverter Defibrillators (ICDs)
- Pneumothorax
- Perforation
- Bleeding
List some complications of catheter ablation for ventricular arrhythmias
- cardiac tamponade
- stroke
- heart block
- vascular access complications
What is the function of dihydropyridine calcium channel blockers? Give 2 examples
- reduce BP
- Nifedipine
- Amlodipine
What is the function of non-dihydropyridine calcium channel blockers? Give 2 examples
- decreases HR
- Verapramil
- Diltiazem
What is the most common and the 2nd most common causative organism of infective endocarditis?
- Staph. aureus
- Strep. viridans
(third is coagulase-negative Staph)
Which criteria is used to diagnose infective endocarditis?
Duke’s Criteria
What are the 2 major criteria of the Duke’s Criteria that is used to diagnose infective endocarditis?
- Blood Cultures
2. Imaging (echocardiogram)
List 3 causes of culture-negative infective endocarditis
- Prior Antibiotic Therapy
- HACEK Organisms
- Uncommon Bacteria (e.g. bartonella, chlamydia, Q fever, brucella, legionella…)
List the HACEK organisms that may cause infective endocarditis
- Haemophilus species
- Aggregatibacter species
- Cardiobacterium hominis
- Eikenella corrodens
- Kingella species
Antibiotic prophylaxis may be used for high-risk groups to prevent infective endocarditis. Which antibiotic(s) may be given?
Amoxicillin
If allergic, Clindamycin or Azithromycin
List the viral and bacterial causes of pericarditis
Viral:
- Coxsackie
- Influenza
- Adenovirus
Bacterial:
- Staph
- Strep
- Chlamydia
- TB
List the clinical features + symptoms of pericarditis
- sharp, pleuritic chest pain
- chest pain relieved by sitting up and leaning forward
- friction rub
- new widespread ST elevation or PR depression
If there is a new widespread ST elevation or PR depression on ECG, what condition is this suggestive of?
pericarditis
What is the treatment for pericarditis?
- NSAIDs ± Cochicine or Steroids
- drainage of pericardial effusion
- antimicrobials (if bacteria identified)
List the possible causative organisms of myocarditis
- Coxsackie
- Influenza
- Corynebacterium diphtheriae
- Toxoplasmosis
List the clinical features + symptoms of myocarditis
- rise in cardiac biomarkers (troponin)
- ECG changes
- acute chest pain
- new/worsening SOB
- palpitations/unexplained arrhythmias
What organisms are mainly involved in cardiac device infections?
Staph. epidermidis
Staph. aureus
aka skin flora
How does a cardiac device infection present?
- local cellulitis w/ discharge + pain
- blood stream infection
- ± endocarditis (usually right-sided endocarditis)
What organisms may be involved in vascular infections (e.g. stent infections)?
Skin Flora: S. epidermidis, S. aureus Enteric Flora (if groin infection): E. coli, Pseudomonas aeruginosa
What should the total cholesterol level be?
< 5.0 mmol/L
What should the LDL cholesterol level be?
< 3.0 mmol/L
What should the HDL cholesterol level be?
> 1.0 mmol/L
List the clinical features of rheumatic fever
- pancarditis (endocarditis, myocarditis, pericarditis)
- migratory polyarthritis
- subcutaneous nodules
- erythema marginatum
- sydenham chorea
Which organism mainly causes prosthetic valve infective endocarditis?
Staph. epidermidis
note: S. aureus mainly causes IVDU endocarditis
Which criteria is used to diagnose rheumatic fever?
(Duckett) Jones criteria
The Jones criteria may be used to diagnose rheumatic fever. List the 5 major and 4 minor criteria for the Jones criteria.
MAJOR:
- Migratory Polyarthritis
- Pancarditis
- Sydenham’s Chorea
- Subcutaneous Nodules
- Erythema Marginatum
MINOR:
- Fever
- Arthralgia
- Elevated CRP or ESR
- Prolonged PR Interval
What is the most common valvular lesion in the elderly?
Aortic Stenosis
List 2 investigations that can be done when investigating PAD
- Doppler Ultrasonography
2. Ankle-Brachial Index (ABI)
List 2 initial treatments of symptomatic PAD
- Supervised Exercise Program
2. Cilostazol (phosphodiesterase inhibitor)
Give 1 drug that may be given to treat symptomatic PAD. What type of drug is it?
Cilostazol - Phosphodiesterase Inhibitor
Which 2 imaging techniques can be done to diagnose an abdominal aneurysm?
- Ultrasound*
2. CT Angiogram
List 5 indications for surgery for an abdominal aneurysm
- Rupture
- Symptomatic
- Rapid Increase in Size (> 1.0 cm/year)
- Asymptomatic >5.5 cm
- Fistulas (aortacaval or aorta-enteric)
What are the 2 treatment options for an abdominal aneurysm?
- EVAR - Endovascular Aneurysm Repair
2. Open Surgery (this is more durable, but more invasive)
When looking at the size of the heart on a PA CXR, what would be considered a normal size?
Diameter of Heart = 50% of Diameter of Thorax
List some of the CXR findings of pulmonary oedema
- dilated upper zone vessels (vascular redistribution)
- Kerley B Lines (septal lines)
- increased interstitial markings
- pleural effusions
- airspace opacification
- Batwing (perihilar) distribution
What are Kerley B lines on CXR and what condition are they a/w?
- due to thickened, oedematous interlobular septa
- due to interstitial oedema
- a/w pulmonary oedema
What disease is a/w polyarteritis nodosa (PAN)?
Hepatitis B
In a thoracic aortic dissection, what is usually seen in the walls?
Cystic Medial Degeneration
List 3 genetic conditions a/w berry aneurysms
- AD polycystic kidney disease (ADPKD)
- Ehler-Danlos
- Marfan’s syndrome
Where do syphilitic aneurysms normally occur?
Thoracic Aorta
Where do capillary micro-aneurysms normally occur?
Intracerebral - Hypertension
Retinal - Diabetics
Where do mycotic aneurysms normally occur?
cerebral arteries
YES. Mycotic and syphilitic aneurysms are different.
List some of the secondary causes of hyperlipidaemia
- diabetes mellitus
- hypothyroidism
- obesity
- alcohol ingestion
Which stain may be used to stain for myocardial fibrosis?
Masson Trichrome
What is the Levine sign?
pt cannot qualify the nature of their discomfort but places their clenched fist in centre of chest
– sign of an MI
Which 2 drugs may be given to treat orthostatic syncope?
- Fludrocortisone
2. Midodrine
What is the most common cardiomyopathy?
Dilated
Why isn’t salbutamol used as an anti-hypertensive?
it causes strong sympathetic reflex tachycardia
List the side effects of amiodarone
thyroid disorders
photosensitivity
liver damage
pulmonary alveolitis
What is the MOA of Class 3 anti-arrhythmic agents?
act by slowing repolarization (phase 3); prolonging the action potential duration
An atrial septal defect is a/w with what condition?
Down’s Syndrome (Trisomy 21)
A ventricular septal defect is a/w what condition?
Foetal Alcohol Syndrome
A patent ductus arteriosus is a/w what condition?
Congenital Rubella Infection
Coarctation of the aorta is a/w what condition?
Turner’s Syndrome (45XO)
List 2 sounds/murmur characteristics of mitral valve prolapse
mid-systolic click
late systolic murmur
HFrEF has an ejection fraction of…
< 40%
HFpEF has an ejection fraction of…
> 50%