drug treatment of AF and HF Flashcards
why is a gallop rhythm indicative of HF
dilated heart
post tussive inspiratory crackles ?
normally due to pulmonary oedema
how to relieve acute HF
sit upright IV frusemide morphine nitrates digoxin oxygen
how to relieve acute HF
sit upright IV furosemide morphine nitrates digoxin oxygen
diuretics
ie furosemide, bumetanide, torsemide
>improve symptoms of pulmonary congestions and decrease body weight
>side effects: dizziness headaches gastrointestinal upset, hypernatremia , hypokalaemia and dehydration
furosemide
primarily eliminated renally
oral bio-availability is erratic and less predictable compared
vasodilators
reduce symptoms in HF and improve haemodynamics by reducing preload, after load or both
decreases BP PCWP (pulmonary capillary wedge pressure) SVR - to reduce dyspnoea and improve peripheral oxygen delivery
morphine
should be considered for patients with severe symptoms of restlessness, dyspnea, anxiety or chest pain
>use with caution (especially with patients with altered mental status and impaired resp. drive, hypotension, bradycardia, advanced atrioventricular block or carbon dioxide retention)
>2.5-5mg IV bolus dose
>usually use with antiemitic
nitroglycerin
-vasodilator
>produces venous vasodilations at lower doses and arterial vasodilation as dosages increase
>reduces preload (pcwp, central venous pressure) and arterial BP thus decreasing cardiac filling pressures and increasing CO
>nitroglycerin is useful in patients with acute HF and hypertension or angina due to coronary vasodilation
>rapid and short acting
>side effects: headache, hypotension, abdominal discomfort. reflex tachycardia , paradoxical bradycardia
digoxin
> has beneficial haemodynamic effects
including vagomimetic effects and ability to decrease ventricular rates - in patients with AF, attenuation of the RAAS, reduced pcwp and svr, increased CO, and improved LVEF
side effects: arrhythmias, cardiac conduction disorder, cerebral impairment, diarrhoea, dizziness, eosinophilia, nausea, skin reactions, vision disorders, vomiting
>has many potential drug interactions
treatment for chronic HF
- oral loop diuretics - (furosemide and bumetanide do not have any neurohormonal antagonism)
- holy trinity - ACEI or ARB, BB, spironolactone (have neurohormonal antagonism)
- ivabradine if BB not tolerated or contra-indicated
- salcubitril/valsartan
ACE inhibitors
RAS blockade
>they prevent the conversion of angiotensin I to angiotension II and also inhibit bradykinin degradation
>have beneficial effects in both the treatment and the prevention of HF
angiotensin II blockers (AT1 antagonists)
acts via a family of cell bound angiotensin receptors
AT1 receptor has been shown to mediate the detrimental effects of angiotensin in patients with HF
>angiotensin II antagonists block the AT1 receptor
RASB side effects
dry cough hypotension renal dysfunction hyperkalaemia >contraindications of the use of ACE inhibitors include angio-oedema, anaphylaxis on prev exposure, pregnancy, bilateral renal artery stenosis
spironolactone
aldosterone levels commonly remain elevated in patients on ACE inhibitors and may contribute to worsening HF
>is a potassium sparing diuretic, is a competitive antagonist of aldosterone and has been shown to have additional benefits
SCD
sudden cardiac death
ICD
implantable cardioverter-defibrillator
>effectively treats malignant ventricular arrhythmias
how to manage AF
rhythm or rate control?
rhythm control if HF is due to AF
rate control is a pragmatic option (sinus rhythm is difficult to achieve in patients with AF associated with HF)
what anti-arrhythmic drugs are safe to use in HF and ischaemic heart disease
amiodarone - kind of safe (long term could be toxic and should not be prescribed with digoxin!)
sotalol can be used in HF but less effective than amiodarone - cam cause renal impairment
Na channels AADIs are
what anti-arrhythmic drugs are safe to use in HF and ischaemic heart disease
amiodarone - kind of safe (long term could be toxic and should not be prescribed with digoxin!)
sotalol can be used in HF but less effective than amiodarone - cam cause renal impairment
Na channels AADIs are contraindicated in CAD
optimal agent for rate control ?
BBs for HF
CCBs (diltiazem and verapamil can worsen LV systolic function and are associated with worse outcomes in HF)
digoxin can be used but has many potential drug interactions
what anticoagulants can be used
NOAC and warfarin but antiplatelets (aspirin/clopidogrel) are not beneficial in AF
what is LBBB
left bundle branch block
>
LBBB + LVHF = ?
cardiac dyssynchrony which worsens LV function and has a worse prognosis
treatment for advanced heart failure
replace frusemide with bumetanide if diuretic resistant then add thiazide diuretic to loop diuretic sacubitril valsartan CRT - cardiac resynchronisation therapy digoxin
entresto
an anti HF drug
promising
>is comprised of sacubitril with valsartan - inhibits nprilysin and hence the breakdown of BNP is prevented (salcubitril)
valsartan is a blockage of the AT1 receptor
»combined leads to vasodilation… decreased BP , decreased sympathetic tone, and decreased aldosterone levels
and natriuresis / diuresis
CRT
biventricular pace maker which has two leads (for each ventricle)
urgent treatment of AF
warfarin (bc of high risk of thromboembolic stroke)
NOACs are contra-indicated
>efficacy has not been tested in clinical trials
>higher risk of thromboembolism and possibly different mechanism of thrombosis, clot extends beyond the left atrial appendage, into the roof and wall of the LA
management of valvular AF
rate control is used BB digoxin rate limited Ca channels blockers consider valve surgery >want stroke prevention, symptoms relief, treat the underlying valve disease with valve surgery disease before irreversibly deleterious structural change
management of NVAF (nonvalvulare AF)
consider changing amlodipine to a rate modulating CCB for BP control and rate control
management of paroxysmal af (PAF)
rhythm control in AF:
flecainide except in HF and CAD
amiodarone and sotalol safe in HF but have serious side effects
RFCA (radio frequency catheter ablation) is preferred especially if there is no structural abnormality
NVAF and anti coag.
risk of stroke
there is a need for anti coagulation if CHA2DS2VASc = 2
stroke risk in NVAF by CHA2DS2VASc score
exceptions to CHA2DS2VASc
oacs strongly indicated regardless of stroke score
>valvular HD
>thyrotoxicosis
>hypertrophic cardiomyopathy
warfarin vs noac
warfarin = many indications individualised dosing and regular INR monitoring drug interactions long half life antidote is Vit K NOAC = limited indications multiple fixed doses and INR monitoring is not required fewer drug interactions less studied short half life no antidote an no proven way to reverse anti coagulation effects if bleeding occurs
NOAC adverse effects
dabigatran -
bleeding anaemia nausea dyspepsia gastritis abdominal pain
increased liver enzymes
allergic reactions
apixaban -
bleeding anaemia
dyspepsia GI bleeding
thrombocytopenia increased liver enzymes
allergic reactions
rivaroxaban -
bleeding anaemia peripheral oedema itch, skin blisters muscle spasms
increased liver enzymes and allergic reaction
