Cardiovascular System Part 1 Flashcards
What are Arrhythmias
Irregular/abnormal heartbeat
Anti-arrhythmic drugs: Membrane Stabilising Drugs
- Disopyramide
- Lidocaine
- Flecainide (not in asthma and severe COPD, ischaemic heart disease
Anti-arrhythmic drugs: Beta Blockers
- Propranolol
Anti-arrhythmic drugs: K+ Channel Blockers
- Amiodarone (4 weeks before and 12 weeks after electrical cardioversion to increase success)
- Sotalol
Anti-arrhythmic drugs: Ca+ Channel Blockers
- Verapamil
- Diltiazem (unlicensed)
Anti-arrhythmic drugs: Other
- Adenosine
- Digoxin
3 Types of Arrhythmias
- Arterial Fibrillation
- Ventricular Arrhythmias
- Paroxysmal Supraventicular Arrhythmias
What is Arterial Fibrillation
Abnormal, disorganised electrical signals fired causing the atria to quiver or fibrillate
Rapid irregular heartbeat
Arterial Fibrillation symptoms
- heart palpitations
- dizziness
- shortness of breath
Arterial Fibrillation complications
- stroke
- heart failure
What is
Cardioversion
Restoring sinus rhythm, using electrical or drug methods
Cardioversion cautions
- Can’t give medication if symptoms are longer than 48 hours (due to increased risk of stroke)
- Use electrical if over 48 hour symptoms
Cardioversion treatment
- Wait until fully anti-coagulated for 3 weeks, then continue with cardioversion
- If haemodynamically unstable, use electrical
Arterial Fibrillation Acute New-onset presentation treatment
With Life Threatening Haemodynamic Instability (unstable blood pressure)
If Life Threatening haemodynamic instability (unstable blood pressure):
- Electrical Cardioversion
Arterial Fibrillation Acute New-onset presentation treatment
Without Life Threatening Haemodynamic Instability (unstable blood pressure)
Without life threatening haemodynamic:
— Within 48 hours: Electrical / Amiodarone
— Later than 48 hours:
Verapamil/Beta-Blocker
Acute Arterial Fibrillation Maintenance Drug Treatment
First Line:
Beta-blockers- Bisoprolol / Propranolol
(not Sotalol, as can prolonge QT interval)
Second Line:
Beta-blocker + Digoxin
Third line:
Oral Anti-arrythmatic drug: Amiodarone
What is Arterial Flutter
It is when heart is short circuited, causing upper chambers to pump rapidly
CHA
Tool (Stroke Prevention)
C - Chronic Heart Failure / Left Ventricular Dysfunction
H - Hypertension
A - Age 75+
DS Tool (Stroke Prevention)
D - Diabetes Mellitus
S - Stroke / Transient ischemic attack / Venous Thromboembolism History
VAS Tool (Stroke Prevention)
V - Vascular Disease
A - 65 to 74 years
S - Sex Category FEMALE
Stroke Prevention Tool Scoring Treatment
> 2: Anticoagulant
< 2: Low Risk
New (non-acute) Onset Arterial Fibrillation treatment
Parental Anticoagulant
(Low molecular weight heparin)
Diagnosed (non-acute) Arterial Fibrillation treatment
Anticoagulant
- Vitamin K Antagonist
(Warfarin)
- Non Vitamin K Antagonist (NOAC)
(Apixaban, Rivaroxaban)
Ventricular Tachycardia Treatment:
- Pulseless / Fibrillation
- Non- Sustained
Pulseless / Fibrillation:
— Defibrillation + CPR
Non-Sustained:
— Beta Blocker
Ventricular Tachycardia Treatment:
Unstable and Stable Sustained Ventricular Tachycardia
Unstable sustained ventricular tachycardia:
— Cardioversion
— Amiodarone + Cardioversion
Stable sustained ventricular tachycardia:
— IV Anti-arrhythmic (Amiodarone)
Maintenance treatment for ventricular tachycardia
— Cardioverter defibrillator implant
— maybe + Sotalol or Beta Blocker + Amiodarone
Prolonged QT Interval Treatment
Magnesium Sulphate
Prolonged QT Interval Causes
Sotalol, Hypokalaemia, Bradycardia
Anti-Arrhythmic Drugs: Class III Anti-Arrhythmic
Amiodarone
Amiodarone Dose
200mg TDS daily for 7 days
then…
200mg BD for 7 days
then…
200mg OD maintenance
Amiadarone side effects: Eyes
— Corneal micro deposites (night glares when driving)
— optic neuropathy
(stop if vision impaired)
Amiadarone side effects: Skin
— Phototoxicity (burning)
— Slate grey skin
(use high spf sunscreen)
Amiadarone side effects: Nerves
— Peripheral Neuropathy (nerve pain)
Amiadarone side effects: Lungs
— Pneumonitis
— Pulmonary Fibrosis
Amiadarone side effects: Liver
— Hepatoxicity
Amiadarone side effects: Thyroid Dysfunction
— Hyperthyroidis (Carbimazole)
— Hypothyroidism (Levothyroxine)
Amiodarone Monitoring
- Annual eye test
- chest x-ray
- liver function tests every 6 months
- Monitor (thyroid stimulating hormone, T3, T4)
- Blood Pressure and ECG
- Serum Potassium
Why is Amiodarone dangerous with Interactions
Long half-life (50 days):
Therefore, danger of post stopping interactions.
Amiodarone and Grapefruit
May increase amount of amiodarone in the body
Amiodarone and Warfarin, Phenytoin and Digoxin
Warfarin
- inhibits warfarin metabolism, associated with major bleeding during warfarin therapy
Phenytoin
- may alter the blood levels of both medications
Digoxin
- inhibit P-glycoprotein system and increase serum levels of digoxin
Amiodarone and Statins
inhibition of the metabolising enzyme by amiodarone, leading to an excess of statin.
Amiodarone and beta-blockers and ccb
increased risk of AV block and myocardial depression
Amiodarone interaction, increasing QT interval and risk of ventricular arrhythmia
Quinolones, macrolides, TCAs, SSRIs, Lithium, Antiphsycotics
Digoxin Mode of Action
Increases force myocardial contraction, reduces conductivity in AV node,
Digoxin Monitoring
Non, unless toxicity or renal impairment
Digoxin Doses
- Loading dose required due to long half life
- Arterial Flutter and Non-Paroxysmal AF in sedentary patients
—125-250 mcg - Worsening/Severe heart failure
— 62.5-125mcg
Signs of Digoxin Toxicity
- Bradycardia
- Nausea/Vomiting
- Diarrhoea
- Abdominal Pain
- Blurred/Yellow Vision
- Confusion
- Rash
Digoxin Toxicity Treatment
- Withdraw (correct electrolyte imbalance)
Digoxin Interactions: Creased
C CB (verapamil)
R ifampicin
A miodarone
S t Johns Wort
E rythromycin
D iuretics
Digoxin Interaction: CCB
Increases serum concentration of Digoxin
Digoxin Interaction: Rifampicin
Reduces digoxin serum levels
Digoxin Interaction: Amiodarone
increases serum digoxin levels
Digoxin Interaction: St Johns Wort
Reduce efficacy of Digoxin
Digoxin Interaction: Erythromycin
increase serum levels of digoxin
Digoxin Interaction: Diuretics
3x times likely increase of digoxin toxicity
Tranexamic Acid Mode of Action and Use
Used to control bleeding
Dose this by:
occupying the necessary binding sites which prevents the dissolution of fibrin, thereby stabilising the clot and preventing haemorrhage
What is tranexamic acid usually prescribed for
heavy periods and nose bleeds
Coagulation factor Deficiency Treatment
Vitamin K
What is Subarachnoid Haemorrhage
Bleeding in space surrounding brain
Subarachnoid Haemorrhage Treatment
Surgery
Blocked Catheter and Line Treatment
UROKINASE
Urokinase Mode of Action
activates plasminogen to plasmin, which in turn degrades fibrin clots
What are the two types of Venous Thromboembolism
- Deep Vein Thrombosis
- Pulmonary Embolism
What is Deep Vein Thrombosis
Blood clot in deep vein, usually in one leg
What is Pulmonary Embolism
Detachment of blood clot, travels to lugs and blocks the pulmonary artery
VTE Risk Assessment
- Immobility
- BMI >30
- Malignant Disease (presence of cancer cells)
- 60+ years
- History / Genetic
- thrombophilic disorders (easy blood clot forming)
- HRT / Contraception
- Pregnancy
Mechanical VTE Prophylaxis
Stockings
(usually for scheduled surgery patients)
Pharmacological VTE Prophylaxis
Parenteral Anticoagulants
- LMW Heparin (unfractionated heparin in renal failure, due to short half life)
- Fondaparinux
VT Antagonist Anticoagulant
- Warfarin
Non-VK Antagonist Oral Anticoagulant
- Edoxaban
Duration of VTE treatment due to surgery
General Surgery
- 5-7 days or until sufficient mobility
Major Cancer, Abdomen or Pelvis Surgery
- 28 Days
Knee/Hip Surgery
- extended duration
VTE in Pregnancy
Heparin/Low molecular weight heparin
- lower risk of osteoporosis and heparin-induced thrombocytopenia
What drug class are Heparins
Parenteral Anticoagulants
2 types of Heparin
- low molecular heparin
- unfractionated heparin
Unfranctionated Heparins Mode of Actions
activates antithrombin
Low Molecular Weight Heparin Mode of Action
inactivates factor Xa
Unfractionated Heparin
- Short duration of action
- used if:
— high risk of bleeding
— renal impairment - essential to measure APTT (how long it takes to clot)
Low Molecular Weight Heparin
Enoxaparin, Dalteparin
- longer duration of action
- used if:
— osteoporosis
— heparin-induced thrombocytopeonia
Side Effects of Heparin
- Haemorrhage (stop heparin, use Protamine)
- Hyperkalaemia (reduces aldosterone secretion)
- Osteoporosis
- Heparin-Induced Thrombocytopoenia (low platelet count)
Other parental Anticoagulants
Argatroban
Hirudin
Epoprostenol
White Warfarin
0.5mg
Brown Warfarin
1mg
Blue Warfarin
3mg
Pink Warfarin
5mg
Dose of Warfarin
5mg initially, monitor every 1-2 days
- Maintenance dose: 3 to 9 mg daily
Isolated Calf DVT warfarin treatment
VTE is limited to lower limbs
Warfarin for 6 weeks
Provoked VTE
VTE with a cause
Warfarin every 3 months
Unprovoked VTE
Warfarin at least 3 months
Monitoring of Warfarin
INR International Normalised Ration
every 3 months once stable
Normal INR Levels
1.1 or below
If a person has VTE, target INR levels are:
2.5
If a person has recurrent VTE, target INR levels are:
3.5
Warfarin yellow booklet
Booklet explaining treatment, and allows for treatment record keeping
What is an anticoagulant alert card
Safety card that provides appropriate details of their treatment
Warfarin and Direct Acting antiviral
changes INR, affects efficacy o warfarin
Monitor INR
Warfarin and Daktarin (miconazole gel:fridge)
miconazole inhibits enzymes, increasing effects of anticoagulant
Stop warfarin when…
Sign of bleeding or blood in urine
Side Effects of Warfarin
- Bleeding
(antidote for bleeding, Vitamin K) - Calciphylaxis: painful rash
(calcium accumulates in small blood vessels of the fat and skin tissues)
— Risk factor of Calciphylaxis: end stage renal disease
If INR is 5 to 8 and no bleeding
- stop taking for 1 to 2 doses
- reduce dose
- measure INR in 2 to 3 days
If INR is 5 to 8 plus minor bleeding
- Stop warfarin
- IV Vitamin K
- restart when INR is below 5
If INR is above 8 and no bleeding
- stop warfarin
- oral vitamin k
- restart when INR is below 5
If INR above 8 and minor bleeding
- stop warfarin
- IV Vitamin K
- restart warfarin when INR is below 5
Warfarine and Elective Surgery
- stop Warfarin 5 days before surgery
- Oral vit K for 1 day id INR 1.5 and above
- Restart warfarin next day
Warfarin and Emergency Surgery
- Try to delay for 6 to 12 hours
- While taking IV Vit K and dried prothrombin complex
Anticoagulant and High risk of bleeding with surgery
Start low molecular heparin 48 hours after surgery
Novel Oral Anticoagulants (NOACs)
Inhibit specific clotting factors, e.g thrombin or factor Xa
Examples of NOACs
- Apixaban
- Edoxaban
- Rivaroxaban
(Direct factor Xa inhibitors) - Dabigatran
(direct thrombin inhibitor (4 months expiry))
Advantages of NOACs over Warfarin
- rarely causes bleeding
- no monitoring requirements
What is an Ischaemic Stroke
Blood clot obstructing supply
transient ischaemic attack:
- mini strokes
Haemorrhagic Stroke
Weak blood vessel in vein bursts
intracerebral haemorrhage
Transient Ischaemic Stroke Management (mini)
Dipyridamole and Aspirin
Ischaemic Stroke Mangament
Clopidogrel
(in arterial fibrillation related stroke, review for anticoagulant)
Both Transient ischaemic and normal ischaemic stroke mangement
Statin
treat hypertension (not with beta blocker)
- unless beta blocker already used for another condition
Intracerbral Haemorrhage treatment
avoid Aspirin, Statins and Anticoagulants
— because they increase bleeding risk
treat hypertension, but avoid hypo perfusion (reduced blood flow)
Antiplatelet drugs mode of action
Decrease platelet aggregation and inhibits thrombus formation in the arterial circulation
Examples of Antiplatelet medication
- Aspirin
- Clopidogrel
- Dipyridamole
- Prasugrel
- Ticagrelor
Aspirin dose for secondary prevention of CVD/event
75 mg daily
When is Clopidogrel used
- following acute coronary syndromes
(conditions related to sudden reduction in blood flow to heart) - following Percutaneous coronary intervention (PCI) (non-surgical procedure to widen or unlock narrowed or blocked coronary artery)
When to use Dipyridamole
secondary prevention of strokes (take 30 to 60 mins before food)
Persantin Retard Capsules have special container (6 week expiry)
Stages of Hypertension
Normal: 120/80
Stage 1: 140/90
Stage 2: 160/100
Stage 3: 180/110
When to start pharmacological management of hypertension: Stage 1 and 2
Stage 1:
Only treat if below 80 with
- diabetes CVD, CVD risk of 20%, renal disease, CKD, retinotherapy, left ventricular hypertrophy)
Stage 2:
Treat all
Stage 3 management scenarios
Hypertensive Emergency with acute target organ damage
- IV bp reduction
- reduce organ perfusion (fluid leak to organ)
Hypertensive Urgency without target organ damage
- oral bp reduction over 24 to 48 hours
Hypertension mangement rule
always titrate up doses before moving to another line
1st Line Hypertension management
If under 55 and not afro/carib with type 2 diabetes
— ACEi
if above 55 or afro/carib or can’t handle cough with type 2 diabetes
— ARB (candesartan and losartan)
if pregnant avoid both ARB and ACEi, and don’t give both at the same time
Above 55, no diabetes or afro/carib
— CCB (amlodipine, diltiazem, felodipine)
— If CCB not tolerated due to oedema, give thiazide like diuretic (indapamide)
2nd Line Hypertension Management
Make sure medication and lifestyle adherence
If already receiving ARB/ACEi add CCB or Thiazide like diuretic
If already receiving CCB/Thiazide like diuretic add ACEi or ARB
3rd Line Hypertension managment
ACEi/ARB
+
CCB
+
Thiazide like diuretic
4th Line Resistant Hypertension management
confirm high BP using ambulatory BP monitoring
add fourth antihypertension drug
4th Line Resistant Hypertension management: how to choose 4th medication
if a patient has Low Potassium (≤ 4.5 mmol/L):
- low-dose spironolactone
(caution with reduced glomerular filtration rate due to hyperkalemia risk.
Monitor sodium, potassium, and renal function at initiation and regularly thereafter)
If a patient has High Potassium (> 4.5 mmol/L):
alpha-blocker
- Doxazosin
Beta-blocker
- Atenolol
- Bisoprolol
- Propranolol
(Monitor potassium levels and adjust treatment as needed)
Under 80 BP Targets
140/90 or less
130/90 or less
in atherosclerotic CVD and diabetes with kidney disease
Over 80 BP Target
150/90 or less
Renal Disease BP Targets
140/90 or less
130/80 or less if CDK, diabetes, proteinuria >1g
Diabetes BP Targets
140/80 or less
130/80 or less if complications of diabetes
Pregnant BP Targets
150/100 or less
140/90 or less if chronic hypertension, target organ damage or given birth
Angiotensin-Converting Enzyme Inhibitor (ACEi) mode of action
Inhibits the conversion of angiotensin 1 to angiotensin 2
Angiotensin 2 receptor blockers mode of action
blocks angiotensin 2 receptor, does not inhibit the breakdown of bradykinin
(alternative to ACEi if coughing or afro/carib)
ACEi Doses
Taken OD and first dose is at bedtime
Captopril only ACEi with BD dose
Perindopril 30-60mins before food
Side Effects of ACEi
- persistant dry cough
- hyperkalaemia (higher risk in renal impairment and diabetes)
Side Effects of ACEi Part 2
- Anaphylactoid reaction (similar to anaphylaxis)
- Oral ulcer
- taste disturbance
- hypoglycaemia
Pregnancy and ACEi
Avoid ACEi
ACEi Renal Effects
- Renoprotective (as it inhibits angiotensin 2)
- Nephrotoxicity (drop in renal perfusion pressure and then decrease in glomerular filtration)
ACEi Hepatic Effects
- Cholestatic jaundice
- hepatic failure
- liver transaminases increase (protein in liver helping with function)
stop taking if liver transaminases are 3x normal (normal is <65) or jaundice
ACEi Interaction that Increase chance of hyperkalaemia
- Aiskeren
- ARB
- K+ sparing diuretics
- Aldosterone Antagonists
ACEi interaction that increases nephrotoxicity and reduces eGFR
- NSAIDs (afferent arteriole constriction
ACEi interaction that increases hypotension
- Diuretics (volume depletion = low blood pressure)
ACEi interaction that produces renal impairment, hyperkalaemia and hypotension
- ARB
- Renin inhibitor
(avoid ACEi and ARB in diabetic nephropathy)
Angiotensin-11 Receptor Blockers (ARB) Mode of Action
Blocks angiotensin 2 recepto. Does not inhibit the breakdown of bradykinin
Centrally Acting Anti-hypertensives Mode of Action
alpha2-adrenoceptor stimulation in the brain stem.
Centrally Acting Anti-hypertensives examples
- Methyldopa (side effects: nausea and dizziness)
- Clonidine (side effects: sleepy, dry mouth, erection problems)
- Moxonidine (side effects: dry mouth, sedation, oedema)
Hydralazine antihypertensive mode of action and side effects
arteriolar dilator acting directly on the smooth muscle of arterioles, resulting in reduced peripheral vascular resistance and reduced blood pressure.
Side Effects: loss of apetite, tachycardia, nausea, fluid retention
Minoxidil antihypertensive mode of action and side effects
opens adenosine triphosphate‐sensitive potassium channels in vascular smooth muscle cells, resulting in vasodilation
Side effects: fluid retention, tachycardia , extra hair growth
Alpha Blockers Antihypertensive Mode of Action
- keep a hormone called norepinephrine from tightening the muscles in the walls of smaller arteries and veins.
- therefore, the blood vessels remain open and relaxed.
Alpha Blocker Examples
- Prazosin
- Terazosin
- Indoramin
Beta-Adrenorecptor Blockers (beta blocker) mode of action
block beta adrenoreceptor in the heart, peripheral vasculature, bronchi, pancreas and liver
Examples of Beta blockers
- atenolol
- bisoprorol
- propranolol
Esmolol (Beta Blocker)
- Esmolol (hypertension in peroperative period-surgical time- as it has a short half life)
Labetalol (Beta blocker)
- Labetolol (hypertension in pregnancy, but hepatoxic)
Sotalol (beta blocker)
- Sotalol (class 3 anti-arrhythmic)
Types of Beta Blockers- 4 types
- Intrinsic sympathomimetic activity
- Water-soluble
- Cardio-selective
- OD Dosing
Intrinsic sympathomimetic activity Beta Blockers (ice PACO)
P indolol
A cebutalol
C eliprolol
O xprenolol
- less bradycardia
- less cold extremities
Water Soluble Beta Blockers (water CANS)
C eliprolol
A tenolol
N adolol
S otalol
- less likely to cross BBB
- less sleep disturbances
(reduce dose in renal impairment)
Cardio Selective Beta blockers (Be A Man)
B isoprolol
A tenolol
M etoprolol
A ceubutol
N ebivolol
- less bronchospasm
OD Dosing beta blocker (BACoN)
B isoprolol
A tenolol
C eliprolol
N adolol
- long duration of action
Side Effects of Beta blockers
- bradycardia
- hypotension
- hyperglycaemia (reduces insulin release)
Contra-indications of beta blockers
- Asthma (causes bronchospasm)
- Worsening unstable heart failure
- Second/degree heart block
- Severe hypotension and bradycardia
Beta blocker interactions
Verapamil Injection
- causes asystole (heart stops beating) and hypotension
Thiazide Like Diuretic
- hyperglycaemia (avoid in diabetes and risk of diabetes)
Calcium Chanel Blockers (CCB)
blocks calcium channels to reduce force of contraction conductivity and vascular tone
Digydropyridine CCB examples
- Amlodipine
- Felodipine
- Lercanidipine
- Lacidipine
- Nifedipine (same S/R brand)
CCB Side effects
- ankle swelling
- flushing
- headaches
Rate Limiting CCB examples
- Verapamil (causes constipation, only CCB for arrhythmias)
- Diltiazem (keep brand if >60mg)
CCB Interactions
avoid grapefruit juice
(it increases CCB concentrations)
What is a phaechromocytoma
tumour in adrenal gland, causing increase in hormone production (epinephrine and norepinephrine)
Phaechromocytoma treatment
- surgery
- if cancerous chemo and radio
- alpha blocker (phenoxybenzamine)
— blunts the effects of catecholamines released from the tumor)
What is a Hypertensive Crisis
Sudden onset of high blood pressure usually =>180/120
Hypotension and Shock
low bp can cause damage to organs, leading to shock.
Vasoconstrictor Sympathomimetics mode of action
raises blood pressure for short period by acting on alpha-adrenergic receptors to constrict peripheral blood vessels
Hypotension induced shock treatment
Vasoconstrictor Sympathomimetics
- epinephrine
- noradrenaline
- phenylephrine (longer lasting bp rise)
Side effects of Vasoconstrictor Sympathomimetics
- reduced perfusion to vital organs