Heart drugs 1 - AF and Heart failure Flashcards
What is the pathophysiology of atrial fibrilation?
Chaotic atrial electrical activity
Fibrosis and loss of atrial muscle mass due to factors like:
-ageing
-chamber dilatation
-inflammation (scarring)
-genetic
What are the risk factors for AF?
-HTN
-Valvular heart disease
-Coronary heart disease
-Cardiomyopathy
-Congenital heart disease
-Previous cardiac surgery
-Pericarditis
-Lung disease e.g., PE, pneumonia, COPD
-Hyperthyroidism (do a TFT)
-Alcohol
What is the classification of AF?
Lone AF
Paroxysmal (< 7 days) - AF comes in waves
Persistent (>7 days)
Permanent (>7 days +/- cardioversion)
What is cardioversion?
A medical procedure that uses quick, low-energy shocks to restore a regular heart rhythm
What are the clinical features of AF?
Asymptomatic
Palpitations
SOB
Chest pain
Syncope (i.e., actually passing out)
Pre-syncope (i.e., feeling that one is going to pass out)
Heart failure
What are the 3 main categories of AF treatment?
Rate control
Rhythm control
Anticoagulation
For someone with recent onset AF who is compromised, what Tx should be given?
DC shock
For someone with recent onset AF who is uncompromised, what Tx should be given?
Pharmacotherapy
For someone with recent onset AF that is < 48 hours duration, what Tx should be given?
Attempt rhythm control
For someone with recent onset AF that is > 48 hours duration, what Tx should be given?
Rate control
In which situations is rhythm control preferred?
Symptom improvement
Younger patient
Heart failure related to AF
Adequacy of rate control
For someone with acute AF without HF what are the 1st and 2nd line drugs?
1st = Beta blocker OR CCB (Diltiazem, Verapamil)
2nd = add digoxin
For someone with acute AF with HF what are the 1st and 2nd line drugs?
1st = Digoxin, amiodarone
2nd = Amiodarone
For someone with permanent or paroxysmal AF what are the 1st and 2nd line drugs?
1st = Beta blocker OR CCB
2nd = add digoxin
What are the indications for rhythm control and what drugs are used for each?
Acute cardioversion (normal heart) = fleicanide, sotalol
Acute cardioversion (abnormal heart) = amiodarone
Maintain sinus rhythm (normal heart) = fleicanide, sotalol
Maintain sinus rhythm (abnormal heart) = amiodarone
Name the non-selective beta blockers
Propranolol
Sotalol
Carvedilol
Name the cardioselective beta blockers
Atenelol - 90% of the drug is renally cleared
Bisoprolol
Esmolol
Metoprolol
Nebivolol
Name the vasodilatory beta blockers
Labetalol
Carvedilol
Name the rate limiting CCBs
Verapamil
Diltiazem
Name the dihydropyridine CCBs
HINT: the “dipines”
Amlodipine - can cross BBB
Nifedipine
Felodipine
Lercanidipine
Nimodipine
What is the CHA2DS2 VASc score and what are the components?
Score that predicts stroke risk in someone with AF
C – Congestive heart failure=1
H – Hypertension=1
A 2– Age >75years=2
D – Diabetes=1
S2 – Previous Stroke, TIA or thromboembolism=2
V – Vascular disease=1
A – Age 65-74 years=1
Sc – Sex category (female gender) =1
What should be done for a CHA2DS2VASc ≥2 ?
Give warfarin OR DOACs (e.g., rivaroxaban, endoxaban)
What is the HAS-BLED score and what are its components?
Estimates risk of major bleeding for patients on anticoagulation to assess quality of AF care
H – Hypertension = 1
A – Abnormal renal/liver function = 1 point each
S – Stroke in the past = 1
B – Bleeding history = 1
L – Labile INRs = 1
E – Elderly = 1
D – Drugs/Alcohol concomitantly = 1 point each
An HAS-BLED score ≥ which number indicates significant risk of bleeding?
3
What other Tx are available for AF?
Radiofrequency catheter or Cryo- ablation
Left atrial appendage occlusion (LAAO) - (used for older persons that cannot be anticoagulated)
What are the main Tx aims for heart failure
Relieve symptoms
Reduce mortality
What are the main Tx categories for HF?
Lifestyle measures – Exercise
– ↓Alcohol
– Smoking Cessation
Drugs
Devices
Surgery
Which of the HF drugs improve symptoms? (use + to indicate how well they improve symptoms)
Diuretics +++
ACEi +
Beta-blockers ++
Aldosterone antagonists ++
ARBs +
Hydralazine/Nitrates +
Digoxin +
Which of the HF drugs reduce mortality? (use + to indicate how well they reduce mortality)
ACEi ++
Beta-blockers +++
Aldosterone antagonists ++
ARBs +
Hydralazine/Nitrates +
Name the diuretics used in HF?
Loop (most commonly used ) e.g.,
furosemide
Thiazides e.g.,
-bendroflumethiazides
-metolazone (thiazide like)-causes profound diuresis
K+ sparing e.g.,
-spironolactone (a mineralocorticoid receptor antagonist)
-amiloride
What are the actions of the different diuretics?
What are the main aims of diuretics?
Provide symptom control
Reduce cardiac pre-load
NOTE: beware of the side-effects they have
What are the benefits of ACEi in HF?
Increased life expectancy vs placebo
Effect more marked in patients with more severe LV dysfunction
Benefit for all NYHA classes
Reduces risk of hospitalisation
What are the actions of ACE-i and ARBs?
Name ACEi
Ramipril
Lisinopril
Enlapril
Perindopril
Catopril (was the first one but not commonly used today due to short half-life)
Name some ARBs
Losartan
Candesartan
Valsartan
What are the benefits of ARBs and in which situation are they used?
Reduces mortality
Some data on QoL, symptom control
Used in patients that cannot tolerate ACEi (as it often causes a dry cough)
What are the benefits of beta blockers?
Increase life expectancy vs placebo (shown in RCT/meta-analyses)
All NYHA classes
Reduces hospitilisation
Evidence for bisoprol, carvedilol and metoprolol
How should you use beta blockers in HF?
Start on low dose and titrate up
Monitor HR, BP and clinical progression
In which group of HF patients is spironolactone used?
Severe heart failure (NYHA III-IV)
What are the advantages of spironolactone in HF?
Increased life expectancy
Reduces hospital admission
Which dose of spironolactone should be used HF?
Low dose - 12.5-25mg
What other drugs are used in chronic HF?
Ivabradine (acts on fun ion channels)- used instead of beta blockers if HR too high (> 75bpm). Works to reduce the HR
Hydralazine + nitrate - used if ACEi/ARB not tolerated/contraindicated or in people of African origin
Sacubritil (neprilysin inhibitor)/Valsartan (ARB)
SGLT2 - can reduce risk for heart failure in patients with T2DM and can decrease risk of major cardiovascular events in patients with HF and diabetes
What are the criteria for prescribing Sacubritil (neprilysin inhibitor)/Valsartan (ARB)?
New York Heart Association class II to IV symptoms
AND
a left ventricular ejection fraction of 35% or less
AND
who are already taking a stable dose of an ACE inhibitor or angiotensin II receptor antagonist.
What are the basic measures for treating someone with acute HF?
Sit patient upright
High dose O2 = corrects hypoxia
What are the initial drug Tx for someone with acute HF?
IV loop diuretics (e.g., furosemide) = cause venodilatation and diuresis
IV opiates/opioids (e.g., morpine/diamorphine) = reduce anxiety and preload (venodilatation)
IV, buccal or sublingual nitrates = reduce preload and afterload, ischaemia and pulmonary artery pressures
If they are already on beta blockers continue but DO NOT initiate it
What other forms of therapy are there for HF (i.e., other non-pharmacological)?
Coronary revascularisation
Cardiac resynchronisation therapy
Cardiac transplantation
Sources
Cardiovascular drugs 1 lecture - 20.11.2019
https://journals.lww.com/tnpj/Fulltext/2021/07000/SGLT2_inhibitors__What_role_do_they_play_in_heart.7.aspx#:~:text=Sodium%2Dglucose%20cotransporter%2D2%20(,in%20patients%20with%20HF%20only.
https://www.nice.org.uk/guidance/ng196/chapter/Recommendations#stroke-prevention
https://www.nice.org.uk/guidance/conditions-and-diseases/cardiovascular-conditions/embolism-and-thrombosis/products?GuidanceProgramme=TA
What are the risk factors for use of dabigatran as anticoagulant in patients with AF?
previous stroke, TIA or systemic embolism
left ventricular ejection fraction below 40%
symptomatic heart failure of New York Heart Association (NYHA) class 2 or above
age 75 years or older
age 65 years or older with one of the following: diabetes mellitus, coronary artery disease or hypertension.
What are the risk factors for use of endoxaban as anticoagulant in patients with AF?
congestive heart failure
HTN
diabetes
prior stroke or TIA
age 75 years or older.
What are the risk factors for use of rivaroxaban as anticoagulant in patients with AF?
congestive heart failure
HTN
age 75 years or older
diabetes mellitus
prior stroke or TIA
What are the risk factors for use of apixaban as anticoagulant in patients with AF?
prior stroke or TIA
age 75 years or older
HTN
diabetes mellitus
symptomatic heart failure.
DOACs are 1st line anticoagulants in AF. If they are not tolerated what class of drugs can be used instead?
Vitamin K antagonists - e.g., warfarin, coumarol, acenocoumarol
