Cardiovascular 1 Flashcards
What is arrhythmia?
A general term for any irregularity in the RHYTHM or RATE of the heartbeat
Can you name some specific types of arrhythmias?
- Ectopic beats
- Atrial fibrillation
- Atrial flutter
- Bradycardia
- Tachycardia
- Ventricular Tachycardia
- Ventricular Fibrillation
- Supraventricular Fibrillation
What are ectopic beats?
- abnormal heartbeat
- occurs outside the normal rhythm of the heart and
DOES NOT ORIGINATE from the hearts NATURAL PACEMAKER (the sinoatrial node) - INSTEAD originates in other areas of the heart such as the ATRIA/ VENTRICILES
What is atrial fibrillation?
RAPID and IRREGULAR electrical impulses fired in the ATRIA (upper chambers of the heart)
Cause ATRIA to FIBRILLATE (quiver)
leading to an IRREGULAR and often RAPID heartbeat
What is tachycardia?
a FAST heart rate
Often exceeding >100beats/ min in ADULTS
What is bradycardia?
a SLOW heart rate (heart beats slower than normal)
Typically fewer than <60 beats/ min in ADULTS
What is atrial flutter?
Rapid contractions of atria
SIMILAR to atrial fibrillation
But occurs in a MORE ORGANIZED and MORE REGULAR PATTERN
What is ventricular tachycardia?
a type of tachycardia that ORIGINATES in VENTRICLES (lower chambers of the heart)
a FAST heart rate
CAN be LIFE- THREATENING and MAY REQUIRE immediate MEDICAL ATTENTION
What is ventricular fibrillation?
a MEDICAL EMERGENCY
can lead to CARDIAC ARREST
It is:
a chaotic and extremely rapid heartbeat in ventricles
results in ventricles quivering instead of contracting#
this means that the heart cannot pump blood effectively
What is supraventricular tachycardia?
A type of tachycardia that originates in a space ABOVE ventricles
This space is NOT the atria by the way!
What is one way to diagnose what arrhythmia a patient is presenting?
ECG
This records the electrical activity of the heart over a period of time
Different arrhythmia= different patterns on ECG
How can we treat spontaneous ectopic heart beats in a patient who otherwise has a normal heart rate?
In these cases, treatment is rarely required. Just reassure the patient
However, if they are troubling the patient:
BETA BLOCKERS
( sometimes effective +may be safer than other suppressant drugs)
What are SYMPTOMS of atrial fibrillation?
HEART PALPITATIONS (pounding/ fluttering)
also:
- dizziness
- shortness of breath
- tiredness
What are COMPLICATIONS of atrial fibrillation?
STROKE
HEART FAILURE
Why would we want to treat atrial fibrillation?
To REDUCE SYMPTOMS
To PREVENT complications (i.e. stroke & heart failure)
What are the 3 different types of atrial fibrillation?
PAROXYSMAL AF
PERSISTENT AF
PERMENANT AF
Define PAROXYSMAL AF
episodes STOP WITHIN 48 hours WITHOUT TREATMENT
smal= small worry
Define PERSISTENT AF
episodes LAST > 7 days
What is PERMENANT AF
AF is present ALL THE TIME
What are the two general ways we treat atrial fibrillation?
Either by
CONTROLLING THE RHYTHM
or
CONTROLLING THE RATE
How is RHYTHM CONTROL achieved?
By CARDIOVERSION
There are TWO types of cardioversion:
- electrical
- pharmacological
What is electrical cardioversion?
Electrodes are placed on the chest
They send electric signals to your heart
To restore and maintain the rhythm of your heart
What is pharmacological cardioversion
Anti- arrhythmic drugs are used to restore and maintain the rhythm of your heart
When can we NOT use cardioversion?
- if symptoms > 48 hours as there is an INCREASED risk of stroke
(basically cause atrial fibrillation can cause blood to pool and clots to form- so longer patient has had symptoms- the higher the chances that a clot has formed)
- if have to do cardioversion tho even tho symptoms > 48 hours, ELECTRICAl IS preferred
What type of therapy should a patient be on BEFORE any cardioversion therapy?
Should this therapy be continued after their cardioversion and if so, HOW LONG FOR AFTER?
ANTICOAGULATION THERAPY for 3 weeks BEFORE cardioversion
AND continue for 4 weeks AFTER
How should patients be anticoagulated before cardioversion therapy?
As arial fibrillation INCREASES the likelihood of clot formation
Therefore, must anticoagulated the patient to get rid of potential clots that may have formed AND also REDUCE risk of clots forming
If we do cardioversion straight away without anticoagulation
- patient may have a clot
- the cardioversion can dislodge this clot and cause it to travel to the brain causing a stroke
What is does ‘haemodynamically unstable’ mean?
A medical condition where the cardiovascular system PARTICULARLY the hearts ability to pump blood is compromised
to the extent that it cannot adequately meet the body’s demands for oxygen and nutritions
How do we treat a patient with ATRIAL FIBRILLATION who is HAEMODYNAMICALLY unstable?
- we must first rule OUT left atrial thrombus (a blood clot forming within the left atrium of the heart)
if patient does not have LEFT ATRIAL THROMBUS
begin ELECTRICAL CARDIOVERSION
AND
PARENTERAL ANTICOAGULANT
(the reason we rule out left atrial thrombus is again so that there isn’t the risk of that clot dislodging during the cardioversion and moving to the brain)
depending on whether its life threatening or not, and also its been <48 hours >48 hours; treatment can vary. Cards coming up on this dw
IF a patients atrial fibrillation TREATMENT FAILS to CONTROL their symptoms OR SYMPTOMS reoccur AFTER CARDIOVERSION; what must be done?
Patient needs SPECIALISED MANAGEMENT
Refer within 4 WEEKS
What pharmacological therapies can we use to CONTROL the HEART RATE in ATRIAL FIBRILLATION?
Beta blockers (not sotalol)
Rate limiting CCB
Digoxin
(monotherapy- dual therapy- rhythm control)
How do rate limiting CBB help CONTROL HEART RATE?
Block calcium channels in the heart
Reduce electrical conduction through atrioventricular node
Slows down heart rate
(The AV node helps regulate heart rhythm)
How do BETA BLOCKERS help CONTROL HEART RATE?
Block adrenaline from binding to beta- adrenergic receptors in the heart
Reduce hearts response to adrenaline
This results in a slower heart rate
How do we treat LIFE- THREATENING HAEMODYANMIC INSTABILITY atrial fibrillation?
Electrical cardioversion
(in reference to previous card, make sure to rule out left atrial thrombus before doing this procedure)
How do we treat NON-LIFE THREATNING haemodynamic instability atrial fibrillation?
< 48 hours
Rate or rhythm control
(for rhythm control use electrical or amiodarone/ flecainide)
> 48 hours
Rate control
(Verapamil, beta- blocker)
What is the first line treatment for MAINTENANCE DRUG TREATMENT for atrial fibrillation?
FIRST LINE IS RATE CONTROL:
Beta blockers (NO SOTALOL)
Rate limiting CCB
Digoxin
(monotherapy- dual therapy- rhythm control)
What is the second line treatment for MAINTENACE DRUG TREATMENT for atrial fibrillation?
SECOND LINE IS RHYTHM CONTROL
Beta blockers OR oral anti- arrhythmic drug
(SOTALOL, OR amiodarone, flecainide, propafenone, dronedarone)
If post- cardioversion therapy; a patient still requires RHYTHM control what treatment do we give?
The second line treatment for maintenance drug treatment for atrial fibrillation is RHYTHM CONTROL
SO GIVE THIS!
How do we treat paroxysmal and symptomatic atrial fibrillation?
(so if symptoms stop within 48 hours without treatment and if they got symptoms of their AFib)
VENTRICULAR CONTROL or RHYTHM CONTROL
- standard beta blocker or oral anti- arrhythmic drug
‘PILL IN POCKET’ if infrequent episodes (self treatment)
- flecainide or propafenone restores sinus rhythm if episode occurs
How do we TREAT ATRIAL FLUTTER?
similar treatment to atrial fibrillation BUT
CATHETER ABLATION = MORE SUITABLE
(ablation creates controlled tissue lesions in the atria- so im guessing it gets rid of the tissues that were generating the abnormal electrical signals)
When do we give anticoagulants?
if the risk of thromboembolic stroke > the risk of bleeding
How is the risk of stroke calculated?
CHA2- DS2- VASc tool
C= chronic heart failure or left ventricular dysfunction
H= hypertension
A2= Age 75+
D= Diabetes Mellitus
S2= stroke/ transient ischaemic attack/ venous thromboembolism history
V= vascular disease
A= 65- 74 years
Sc= Sex category (male/ female)
What score of CHA2- DS2- VAsc tool suggest patient NEEDS ANTICOAGULANT therapy?
If score is 2 OR MORE
What score of CHA2- DS2- VAsc tool suggest patient DOES NOT NEED ANTICOAGULANT therapy?
Male= 0
Females= 1
What anticoagulant do we give FOR NEW ONSET ATRIAL FIBRILLATION?
Parenteral anticoagulation
What anticoagulant do we give for DIAGNOSED ATRIAL FIBRILLATION?
warfarin or NOAC
What are NOAC?
new oral anticoagulants
When do we give NOACs?
in NON VALVULAR Afib
with ≥ 1 risk factors which are: 75+, heart failure, hypertension, diabetes mellitus, previous stroke or TIA
What is TIA?
Transient ischemic attack
A mini stroke
It is the temporary disruption of blood flow to a aprt of the brain
It is a WARNING sign of INCREASED RISK of FUTURE stroke
what is the HAS- BLED tool?
a risk assessment to estimate the risk of bleeding
It helps to evaluate the POTENTIAL BENEFITS of anticoagulation vs POTENTIAL RISKS
(use in conjunction with CHA2- DS2- VASc tool)
What does the HAS- BLED tool stand for?
H= hypertension
A= abnormal renal/ liver function
S= stroke history
B= bleeding history or predisposition
L= Labile international normalized ratio
E= elderly (age>65 years)
D= drug or alcohol use
The higher the score (it is out of 9 in total), the higher the risk of bleeding complications
what is labile INR?
labile INR means fluctuations in values of INR.
Suggests difficulty in maintain consistent anticoagulation levels= increasing risk of bleeding
Why do drugs and alcohol increase risk of bleeding?
As they can increase the risks of falls/ trauma
Therefore, CONTRIBUTE to BLEEDING COMPLICATIONS
What are the different types of VENTRICULAR TACHYCARDIA?
- pulseless ventricular tachycardia
- unstable sustained ventricular tachycardia
- stable sustained ventricular tachycardia
- non- sustained ventricular tachycardia
what is PULSELESS ventricular FIBRILLATION?
LIFE- THREATENING
In VF, the heart’s electrical signals become chaotic and disorganized.
the ventricles (the lower chambers of the heart) quiver or fibrillate instead of contracting effectively.
the heart is unable to pump blood to the body.
The absence of a pulse indicates that the heart is not generating enough blood flow to maintain organ function.
VF is a medical emergency
immediate intervention with CPR (cardiopulmonary resuscitation) and defibrillation (shocking the heart) is required to restore normal heart rhythm and save the person’s life.
PULSE is NOT PRESENT
Patients with pulseless VF are in cardiac arrest. They are unresponsive, not breathing normally, and have no palpable pulse.
What is pulseless ventricular TACHYCARDIA?
LIFE- THREATENING
a rapid heart rhythm that originates in the ventricles.
In VT, the heart beats at a very fast rate, but the contractions may not be coordinated or effective.
The heart may still be beating fast enough to generate a pulse, but in “pulseless VT,” there is no detectable pulse.
Pulseless VT is a medical emergency, as it indicates inadequate circulation.
Treatment for pulseless VT includes CPR and immediate defibrillation, similar to VF.
PULSE is NOT PRESENT
Patients with pulseless VT are in cardiac arrest. They are unresponsive, not breathing normally, and have no palpable pulse.
What is defibrillation?
Defibrillation is a medical procedure that involves the use of an electrical shock to restore the normal rhythm of the heart in cases of life-threatening cardiac arrhythmias, particularly ventricular fibrillation (VF) and pulseless ventricular tachycardia (VT).
The goal of defibrillation is to “reset” the heart’s electrical activity, allowing it to resume a coordinated and effective pumping action.
In such cases where defibrillation has not been successful in restoring a normal heart rhythm and pulse, what must be done?
Iv amiodarone is given refractory to defibrillation
Amiodarone is a potent antiarrhythmic drug that can be administered intravenously. It works by affecting the electrical properties of the heart and can help stabilize the rhythm.
What is UNSTABLE sustained ventricular tachycardia?
a serious cardiac arrhythmia characterized by a rapid and abnormal heart rhythm originating in the ventricles, the lower chambers of the heart.
In this context, “unstable” refers to the fact that the patient’s condition is deteriorating or at risk of deteriorating due to the arrhythmia. It is a medical emergency that requires immediate attention and intervention.
PULSE is present
have symptoms of haemodynamic instability: such as severe chest pain, palpitations, shortness of breath, dizziness, or altered consciousness.
How is unstable sustained ventricular tachycardia treated?
direct current cardioversion
If this fails give IV amiodarone and repeat direct current
What is stable sustained ventricular tachycardia?
Stable sustained ventricular tachycardia (VT) is a cardiac arrhythmia characterized by a rapid and regular heart rhythm originating in the ventricles, the lower chambers of the heart.
In this context, “stable” means that the patient is not experiencing severe symptoms or hemodynamic instability, and they are conscious and alert despite the abnormal rhythm.
How do we treat stable sustained ventricular tachycardia?
IV anti- arrhythmic drug (amiodarone preferred)
What is non- sustained ventricular tachycardia?
Non-sustained ventricular tachycardia (NSVT) is a cardiac arrhythmia characterized by episodes of rapid heartbeats originating in the ventricles (the lower chambers of the heart) that last for a brief duration, typically less than 30 seconds.
How do we treat non- sustained ventricular tachycardia?
beta- blocker
can slow down the heart rate by blocking the effects of adrenaline (epinephrine) on the heart
What is the maintenance treatment for patients at high risk of cardiac arrest?
MOST PATIENTS: cardioverter defibrillator implant
SOME PATIENTS also require a drug: sotalol, beta- blocker alone or beta- blocker with amiodarone
What is TORSADE DE POINTES (prolonged QT interval)?
a specific type of ventricular tachycardia, a rapid and abnormal heart rhythm originating in the ventricles, the lower chambers of the heart.
often associated with a prolonged QT interval on the ECG. The QT interval represents the time it takes for the ventricles to repolarize (reset) after each heartbeat. A prolonged QT interval can lead to a susceptibility to TdP.
How is TORSADE de POINTES treated?
magnesium sulphate
because it addresses one of the underlying factors that can trigger this specific type of ventricular tachycardia—namely, electrolyte imbalances, particularly hypomagnesemia (low levels of magnesium in the blood)
What are the CAUSES of TORSADE de POINTES
sotalol and other drugs that prolong QT interval
hypOkalaemia
bradycardia
why can sotalol prolong QT interval?
It can prolong the QT interval on an electrocardiogram (ECG) due to its action on potassium channels in the heart.
What is paroxysmal supraventricular tachycardia? PSVT
is a type of cardiac arrhythmia characterized by sudden and intermittent episodes of abnormally fast heart rate.
This rapid heart rate originates above the ventricles, usually in the atria or atrioventricular (AV) node, which are the upper chambers of the heart.
How is paroxysmal supraventricular tachycardia treated?
Terminates spontaneously or with reflex vagal nerve stimulation e.g. Valsalva manoeuvre, carotid sinus massage or immersing face in ice cold water
/
IV adenosine (BUT contra- indicated in COPD/ asthma)
/
Iv Verapmil
What is reflex vagal nerve stimulation
stimulating the vagus nerve (cranial nerve X), leads to various physiological responses, including changes in heart rate, blood pressure
this nerve can be stimulated by e.g. Valsalva manoeuvre, carotid sinus massage or immersing face in ice cold water
Valsalva maneuver involves forceful exhalation against a closed airway (like trying to exhale against a closed mouth and nose). This increases pressure within the chest and can stimulate the vagus nerve.
Carotid sinus massage involves gently massaging the carotid sinus, a small area near the carotid artery in the neck. This stimulation can lead to activation of the vagus nerve and result in a slowing of the heart rate
Plunging the face into ice-cold water or applying cold stimuli to the face can stimulate the trigeminal nerve, which is closely connected to the vagus nerve. This can lead to a vagal response, including bradycardia (slowing of the heart rate).
How does adenosine help treat PSVT?
It works by briefly blocking electrical signals in the heart’s AV node, which can interrupt the abnormal rhythm causing PSVT and restore a normal heart rate
How do we treat haemodynamically unstable PSVT?
direct current cardioversion
How do we treat recurrent episodes of PSVT?
catheter ablation OR drugs (verapamil, diltiazem, beta- blockers, flecainide or propafenone)
What is amiodarone?
a class III anti- arrhythmic drug
what is the initial loading dose of amiodarone?
200mg TDS for 7 days
200mg BD for 7 days and then
200mg OD as maintenance
Where can pts experience side effects of amiodarone?
EYES, SKIN, NERVES, LUNGS, LIVER, THYROID DYSFUNCTION
What are the EYE side effects of amiodarone?
How will you counsel patients?
1) Corneal micro- deposits
PATIENT COUNSELLING: night time glares when driving
2) Optic neuropathy/ neuritis (blindness)
PATIENT COUNSELLING: STOP if impaired vision
Amiodarone contains iodine, which can deposit in various tissues, including the cornea of the eye.
What are the SKIN side effects of amiodarone?
How will you counsel patients?
1) Phototoxicity (burning, erythema)
2) Slate - grey skin on light exposed areas
PATIENT COUNSELLING: shield skin from light during treatment. Use wide spectrum, high SPF sunscreen for months after stopping
(Phototoxicity (photoirritation) is defined as a toxic response that is elicited after the initial exposure of skin to certain chemicals and subsequent exposure to light)
The skin reactions are thought to be related to the drug’s accumulation in the skin and its effects on pigmentation.
What are the NERVE side effects of amiodarone?
How will you COUNSEL patients?
Peripheral neuropathy
PATIENT COUNSELLING: to look out for numbness, tingling hand, and feet’s, tremors
may involve direct drug toxicity to nerves and muscles
What are the LUNG side effects of amiodarone?
How will you COUNSEL patients?
Pneumonitis, pulmonary fibrosis
PATIENT COUNSELLING: shortness of breath, dry cough
The exact mechanism of amiodarone-induced lung toxicity is not fully understood, but it is thought to involve inflammation and fibrosis in the lung tissue.
What are the LIVER side effects of amiodarone?
How will you COUNSEL patients?
Hepatoxicity
PATIENT COUNSELLING: patients must REPORT jaundice, nausea, vomiting, malaise, itching, bruising, abdominal pain, 3x raised liver transaminases
The precise cause of amiodarone-induced liver toxicity is not well understood, but it may involve direct toxicity to liver cells.
What are the THYROID side effects of amiodarone?
Amiodarone contains iodine, which can disrupt the normal regulation of thyroid hormones. It may also cause inflammation of the thyroid gland
Can cause THYRPOD DYSFUNCTION - Can cause hypo and hyperthyroidism
Hyperthyroidism e.g. weight loss, heat intolerance, tachycardia. Give carbimazole if necessary. Withdraw amiodarone
Hypothyroidism e.g. weight gain, cold intolerance, bradycardia. Start levothyroxine without withdrawing amiodarone if essential
How can we monitor patients on amiodarone?
EYES: annual eye test
LUNGS: chest x- ray before treatment
LIVER: liver function tests every 6 months
THYROID: monitor TSH, T3, T4 before treatments and every 6 months
as can also cause HYPOTENSION and BRADYCHARDIA: monitor blood pressure and do ECGs
amiodarone causes HypOkalaemia, this enhances arrhythmogenic effects of amiodarone. MONITOR SERUM POTASSIUM
Why are there danger of interactions with AMIODARINE several months AFTER STOPPING?
Amiodarone has an EXTREMELY LONG HALF-LIFE (around 50 days)
Why should you avoid grapefruit juice whilst taking amiodarine?
grapefruit juice REDUCES amiodarone metabolism
leads to INCREASED plasma amiodarone concentration
the concentration of amiodarone in your bloodstream can increase significantly. Higher amiodarone levels can increase the risk of side effects and toxicity associated with the medication.
Why does amiodarine interact with warfarin, phenytoin and digoxin (half)?
amiodarine is a is a potent inhibitor of enzymes that are responsible for metabolising for these drugs
increasing their levels in the blood + increase risk of side effects
Why does amiodarine interact with statins?
like statins, amiodarone is associated with an increased risk of myopathy, which is a condition characterized by muscle pain, weakness, or inflammation.
Why does amiodarone interact with BETA BLOCKERS and RATE LIMITING CCBs?
Basically all these drugs SLOW DOWN HEART RATE
When amiodarone is used in combination with beta blockers or rate-limiting CCBs, the cumulative effect of all these medications can result in significant bradycardia. This means the heart rate can become dangerously slow.
Therefore can lead to BRADYCARDIA, AV BLOCK and MYOCARDIAL DEPRESSION
Atrioventricular (AV) block is a type of heart block that occurs when there is a disruption or delay in the transmission of electrical signals between the atria (the upper chambers of the heart) and the ventricles (the lower chambers of the heart).
Myocardial depression refers to a condition where the heart muscle (myocardium) becomes weakened and less able to pump blood effectively.
Amiodarone is known to interact with a variety of MEDICATIONS, potentially leading to a prolongation of the QT interval on an electrocardiogram (ECG)
This increases risk of ventricular arrhythmia
Give examples of such MEDICATIONS
Quinolones
Macrolides
TCAs
SSRIs
Lithium
Quinine
Hydroxychloroquine
Anti- malarials (chloroquine, mefloquine)
Antipsychotics (especially sulpiride, primozide, amisulpride)
What is digoxin?
1-2mcg/L
Cardiac glycoside
High risk drug
What is a positive inotrope?
A positive inotrope is a substance or medication that increases the force of contraction of the heart muscle, improving its ability to pump blood.
e.g digoxin
What is a negative inotrope?
A negative inotrope is a substance or medication that decreases the force of contraction of the heart muscle, reducing its ability to pump blood
e.g. beta blockers, calcium channel blockers
What is the mechanism of action of digoxin?
It enhances myocardial contractility by inhibiting the sodium-potassium pump (Na+/K+ pump) in heart muscle cells. This inhibition leads to an increase in intracellular calcium levels, which improves the force of cardiac muscle contraction.
What are the therapeutic levels of digoxin?
Therapeutic levels of digoxin refer to the range of blood concentrations at which the medication is effective in treating specific heart conditions while minimizing the risk of toxicity.
1-2 mcg/ L (Cp 6 hours after dose)
Is regular monitoring required for digoxin maintenance therapy?
NO
unless toxicity suspected or in renal impairment (as digoxin is cleared renally)
Why are loading doses required for digoxin?
As it has a long half life
What is the maintenance once daily dose of DIGOXIN for ATRIAL FLUTTER and NON- PAROXYSMAL AF in sedentary patients?
125- 250 mcg
What is the maintenance once daily dose of DIGOXIN for WORSENING OR SEVERE HEART FAILURE (in sinus rhythm)?
62.5- 125 mcg
What are the bioavailability’s of digoxin when it is in the following different dosage forms?
ELIXIR
TABLET
IV
ELIXIR= 75%
TABLET= 90%
IV= 100%
When is there a risk of digoxin toxity?
risk of toxicity in hypO K+
hypo Mg2+
hyper Ca2+
hypoxia and renal impairment
What are signs of toxicity?
“SLOW AND SICK”
- bradycardia/ heart block
- nausea, vomiting and diarrhoea, abdominal pain
- blurred or yellow vision
- confusion, delirium
- rash
What is the treatment for digoxin toxicity?
Withdraw: correct electrolyte imbalances
Using digoxin- specific antibody for life- threatening ventricular arrhythmias unresponsive to Atropine
HypOkalaemia predisposes to digoxin toxicity.
What drugs cause this?
Diuretics (loop/ thiazide)
B2 agonist
Steroids
Theophylline
(If K+ <4.5mmol/L: give K+ supplements or K+ sparing diuretic (preferred))
What drugs INCREASE plasma digoxin concentration?
Amiodarone (give half digoxin dose)
rate limiting CCBs. macrolides, ciclosporin (enzyme inhibitors)
What drugs decrease plasma digoxin concentration
St Johns wart, rifampicin (enzyme inducers- speed
up metabolism of digoxin)
What drugs decrease renal excretion?
Why can this cause digoxin toxicity?
NSAIDs, ACE inhibitors/ ARBs
Digoxin is renally excreted therefore drugs that decrease renal excretion= increase digoxin plasma conc
What drugs does digoxin interact with
- drugs that cause hypokalaemia e.g. diuretics, b2 agonists etc
- drugs that are enzyme inhibitors and INCREASE plasma digoxin conc e.g. amiodarone, rate limiting CBBs
- drugs that are enzyme inducers and DECREASE plasma digoxin conc e.g. st johns wart
- drugs that reduce renal excretion and INCREASE plasma digoxin conc as digoxin is renally excreted e.g. NSAIDs, ACE inhibitors/ ARBs
“CRASED” is an acronym for digoxin interations.
Write out this acronym
C= calcium channel blockers (verapamil)
R= rifampicin
A= amiodarone
S= St johns wart
E= erythromycin
D= diuretics
Digoxin is said to have a narrow therapeutic index. What does this mean?
means the difference between a therapeutic and toxic dose is relatively small.
Therefore, careful monitoring of blood levels and clinical symptoms is essential when using these medications
what is the usual dose of edoxaban for prophylaxis of stroke in atrial fibrillation?
60mg ONCE daily
HOWEVER,
30mg ONCE daily if:
on current treatment with ‘ DECK’
Dronedarone
Erythromycin
Ciclosporin
Ketoconazole
OR
if body weight < 61 kg
Why do we use DOACs in atrial fibrillation?
to reduce the risk of stroke and systemic embolism
as atrial fibrillation can lead to the formation of blood clots within the atria. If these clots dislodge and travel to the brain, they can cause a stroke
why are DOACs preferred over Warfarin?
Predictable pharmacokinetics: Unlike warfarin, which requires regular monitoring of INR and dose adjustments, DOACs have more predictable pharmacokinetics and do not require routine monitoring, making them more convenient for patients.
Fewer drug and food interactions: DOACs have fewer interactions with other drugs and foods compared to warfarin, simplifying their use in clinical practice.
Lower risk of bleeding: DOACs have a lower risk of causing major bleeding, such as intracranial hemorrhage, compared to warfarin.
Rapid onset and offset of action: DOACs have a rapid onset of action, providing anticoagulation more quickly than warfarin, and their effects diminish rapidly once the medication is stopped, reducing the risk of bleeding complications during surgical procedures or emergencies.
However, the choice of anticoagulant therapy should be individualized based on the patient’s specific clinical characteristics, including their risk of stroke and bleeding, renal function, and other comorbidities. Regular follow-up and monitoring are necessary to ensure the safety and efficacy of DOAC therapy
give examples of DOACs
dabigatran, rivaroxaban, apixaban, and edoxaban
What is the Step 1 treatment for HYPERTENSION WITH TYPE 2 DIABETES
ACEi or ARB
(if not tolerated then beta- blocker)
What is the Step 1 treatment for HYPERTENSION WITHOUT TYPE 2 DIABETES
Age <55 and not of black African or African- Caribbean family origin?
ACEi or ARB
(if not tolerated then beta- blocker)
What is the Step 1 treatment for HYPERTENSION WITHOUT TYPE 2 DIABETES
Age 55 or over
CCB
if high risk of heart failure or CBB not tolerated: give thiazaide like diuretc TLD
What is the Step 2 treatment for a patient already recieving ACEi or ARB?
Give CCB or thiazide like diuretic
What is the Step 1 treatment for HYPERTENSION WITHOUT TYPE 2 DIABETES
Black African or African- Carribean family origin
CCB
if high risk of heart failure or CBB not tolerated: give thiazaide like diuretc TLD
What is the Step 2 treatment for a patient already recieving CCB?
Give ACEi or ARB or thiazide like diuretic
*if patient is African/ Carribean, ARB is preferred in their second line treatment
What is the Step 3 treatment for someone who needs antihypertensive drug
ACEi or ARB
+CCB
+ thiazide like diuretic
(give a low dose spironaloctone as the TLD. However, you can give a higher dose TLD if their K+ levels > 4.5)
If other diuretics are ineffective. ADD ALPHA or BETA- BLOCKER
What is the Step 4 treatment for someone who needs antihypertensive drug
confirm resistant hypertension
confirm elevated BP with ABPM or HBPM
check for postural hypotension and discuss adherence
Consider seeking expert advice or adding a:
- low dose spironolactone if blood potassium level is ≤4.5mmol/L
- alpha blocker or beta blocker if blood potassium level is >4.5mmol/L
seek expert advice if BP is uncontrolled on optimal tolerated doses of 4 drugs
Why should you avoid TLD and beta- blocker together ESPECIALLY in diabetes or high risk of diabetes?
both drugs cause hypoglycaemia
CCB
calcium channel blocker
TLD
thiazide like diuretic
ACEi
Ace inhibitor
ARB
Angiotensin II receptor blocker
What is normal hypertension
120/ 80 mmHg
What should you do if a patient has blood pressure of 140/90?
When would you treat such a patient?
OFFER LIFESTYLE ADVICE
ONLY TREAT IF UNDER 80 with:
- target organ damage (left ventricular hypertrophy, CKD, retinopathy)#
- CVD or 10 year CVD risk >20%, renal disease, diabetes
What should you do if a patient has a blood pressure of 160/90?
ALL patients with such a blood pressure SHOULD be treated
What should you do if a patient has a blood pressure of >180 as their SYSTOLIC and >110 as their DIASTOLIC?
This is a HYPERTENSIVE CRISES.
It can be either a HYPERTENSIVE EMERGENCY or a HYPERTENSIVE URGENCY
What is hypertensive emergency
HYPERTENSIVE EMERGENCY:
- in a hypertensive emergency, the blood pressure is so high that it is causing immediate and severe damage to one or more critical organs. This is a life-threatening situation that requires rapid medical intervention, typically in a hospital setting, to lower the blood pressure and prevent further organ damage or complications.
-Treatment involves IV medications to lower blood pressure rapidly. Otherwise can have: reduced organ perfusion= blindess, MI, cerebral infarcation and severe renal impairment
What is hypertensive urgency
blood pressure is significantly elevated but does not currently exhibit acute or immediate target organ damage. Unlike a hypertensive emergency, where there is evidence of acute organ damage, hypertensive urgency is characterized by the high blood pressure itself without other acute symptoms or complications.
Treatment: Oral medications to reduce blood pressure slowly over 24- 48 hours.
(gradually and safely lower the blood pressure over a period of hours to days to reduce the risk of complications over the long term)
what is reduced organ perfusion
inadequate perfusion (blood flow) to vital organs
can result in organ damage
hypertensive emergency can cause reduced organ perfusion
(Chronic high blood pressure can cause the arteries and arterioles (smaller blood vessels) to constrict or narrow. When blood vessels narrow, it increases resistance to blood flow, making it harder for blood to move through these vessels. As a result, blood flow to organs and tissues can be compromised, reducing perfusion.)
why can high blood pressure lead to retinopathy?
Extremely high blood pressure can damage the blood vessels in the eyes, leading to retinopathy. Rapid reduction of blood pressure can help prevent or minimize this eye damage and reduce the risk of blindness.
why can severe high blood pressure lead to myocardial infarction (heart attack)
Severe hypertension can place excessive strain on the heart, increasing the risk of a heart attack (myocardial infarction). Lowering blood pressure quickly can reduce this strain and minimize the risk of cardiac events.
why can high blood pressure cause kidney damage?
reduced organ perfusion
Impaired blood flow to the kidneys can lead to kidney dysfunction or failure.
What are clinical blood pressure targets in: UNDER 80 YEARS?
IF they have atherosclerotic CVD* or diabetes with kidney, eye or cerebrovascular disease**
130/80
For EVERYONE ELSE
<140/90
- a condition in which fatty deposits (plaques) build up on the inner walls of arteries.
** a group of medical conditions that affect the blood vessels and blood supply to the brain
What are clinical blood pressure targets in: OVER 80 YEARS?
<150 /90
What are clinical blood pressure targets in: pts with RENAL DISEASE
IF CKD, Diabetes, proteinuria > 1g in 24 hours:
< 130/ 80
(consider ACEi/ ARB if proteinuria present)
FOR EVERYONE ELSE:
<140/90
what are clinical blood pressure targets in: pts with DIABETES?
IF have complications with their diabetes such as: EYE, KIDNEY or CEREBROVASCULAR DISEASE
<130/80
FOR EVERYONE ELSE
<140/80
(THIS IS NOT A TYPO, IT ACTUALLY IS 80 AND NOT 90!)
What are clinical blood pressure targets in: pregnant pts?
CHRONIC HYPERTENSION
<140/90
CHRONIC HYPERTENSION & if target organ damage or have already given birth
<140/90
What drug is widely used as first choice in gestational hypertension?
Labetalol
(this drug is hepatotoxic- remember that
Other drugs include:
methyldopa (stop 2 days after birth)
nifedipine MR (unlicensed)
What is the mechanism of action of angiotensin- converting enzyme inhibitors?
Inhibits the conversion of angiotensin I to angiotensin II
Angiotensin II is a potent vasoconstrictor, meaning it narrows blood vessels, leading to increased blood pressure. It also stimulates the release of aldosterone, which promotes sodium and water retention by the kidneys, further raising blood pressure.
Therefore ACEi inhibiting the conversion of angiotensin I to angiotensin II, ACE inhibitors cause blood vessels to dilate or relax. This dilation reduces peripheral vascular resistance, which is the resistance that the heart must overcome to pump blood through the circulatory system. As a result, blood pressure decreases, and the workload on the heart is reduced.
ACE inhibitors also lead to a decrease in the production of aldosterone, a hormone that acts on the kidneys to increase the reabsorption of sodium and water. By reducing aldosterone levels, ACE inhibitors promote the excretion of sodium and water by the kidneys, which helps lower blood pressure and reduce fluid retention.
Give examples of ACE inhibitors?
Captopril (BD)
ENALAPRIL
Fosinopril
Imidapril
LISINOPRIL
Moexipril
PERINDROPIL (30- 60 minutes before food)
Quinapril
RAMPIRIL
Trandolapril
All ACEi inhibitors should be done once a take except for one of them. What is this and what is its dosing?
CATOPRIL
should be taken BD
When should a patient take their first dose of ACEi
At bedtime
(could be to mitigate side effects, as individuals may sleep through the initial period when side effects are most likely to occur)
What are examples of Angiotensin II receptor blockers (ARB)?
Azilsartan
CANDERSARTAN
eprosartan
Irbersartan
LOSARTAN
Olmesartan
Telmisartan
VALSARTAN
What are side effects of ACEi?
persistent dry cough: give ARB as alternative
hyperkalaemia: higher risk in renal impairment and diabetes mellitus
anaphylactoid reactions* e.g. angioedema**
OTHER SIDE EFEFCTS:
oral ulcer, taste disturbance and hypOglycaemia
*non-allergic anaphylaxis but are not caused by the immune system’s production of IgE antibodies.
**condition characterized by the sudden and often rapid swelling of deeper layers of the skin, usually in areas such as the face, lips, tongue, throat
What is anaphylaxis
a severe and potentially life-threatening allergic reaction that can occur rapidly and affect multiple organ systems in the body. It is characterized by a sudden and systemic release of chemical mediators, including histamines, that lead to a wide range of symptoms.
Allergic Anaphylaxis: This type of anaphylaxis occurs when the immune system recognizes a specific allergen as harmful and mounts an exaggerated immune response. The immune system produces IgE antibodies in response to the allergen, and upon re-exposure, these antibodies trigger the release of histamines and other chemicals
Non- allergic anaphylaxis: does not involve IgE-mediated immune responses. Instead, non-allergic anaphylaxis occurs when certain substances, such as some medications (e.g., radiocontrast dye, certain opioids), directly trigger the release of histamines and other mediators, leading to similar severe symptoms. The key difference is that non-allergic anaphylaxis does not involve the production of IgE antibodies or prior sensitization to an allergen.
(basically in allergic its the IgE antibodies that stimulate the release of the histamines BUT in non-allergic the thing thats irritating is releasing the histamine all by itself)
Out of ACEi and ARBs, which one is renoprotective in renal disease such as CKD?
ARB
Some drugs are NEPHROTOXIC and should be avoided in AKI. DAMN is the acronym to describe these drugs.
Spell out the DAMN acronym
D= diuretics
A= ace inhibitors/ arbs
M= metformin
N= Nsaids
Why should ARBs be avoided in renovascular disease?
reduces eGFR via efferent arteriole dilation
May give in unilateral renal artery stenosis* BUT not severe bilateral stenosis
*Unilateral renal artery stenosis is a medical condition characterized by the narrowing or constriction of one of the renal arteries, which are the blood vessels that supply blood to the kidneys. “Unilateral” means that only one of the renal arteries is affected, while the other remains normal.
What is renovascular disease
Renovascular disease refers to conditions that affect the blood vessels supplying the kidneys. It often involves the narrowing or blockage of these blood vessels, which can reduce blood flow to the kidneys and potentially lead to high blood pressure and kidney dysfunction.
What are the hepatic effects of ARBs?
cholestatic jaundice
hepatic failure
*s a type of jaundice that occurs when there is an interruption in the normal flow of bile from the liver to the small intestine.
In relation the the hepatic effects of ARBs, when must we stop ARBs?
if liver transamines 3x normal
or
jaundice occurs