Drug treatment of Cardiovascular diseases Flashcards
what is the role of vascular endothelium
- Role in regulation of vascular tone
- Controls tissue blood flow
- Inflammatory responses
- Maintain blood fluidity
what happens when there is damage to vascular endothelium
creates risk to cardiovascular disease
what are the types of cardiovascular disease
- Coronary heart disease
- Stroke and TIAs
- Peripheral arterial disease
- Aortic disease
what is disease pathophysiology
loss of normal physiological function
how do you treat disease pathophysiology
- Treatment rationale; direct disease pathology back towards normal function, for example if a person has high blood pressure you want to return the blood pressure to within a normal range
why is it important to treat hypertension
- This is because high blood pressure causes an increase risk in cardiovascular disease
how do you manage hypertension
lifestyle and medication
what changes in lifestyle can reduce hypertension
- Environment/lifestyle are very important
- Salt and smoking especially
- Salt minimisation benefit is that entire family/household benefits – good practice for life
how do you treat hypertension with drugs
- Multiple options directed at modulating physiological pathways affecting BP
- Evidence base for order of drug choices in different populations (age and race based)
- Many people need >1 drug targeting different contributing pathways
what anithypertensive drugs should those aged under 55 be given firstly
ACE inhibitors
what anithypertensive drugs should those aged over 55 be given firstly
calcium channels blockers
what does it mean when the individual has resistant hypertension
- If the individual has resistant hypertension which means they have good adherence to the antihypertensive drugs then you consider diuretics and beta blockers
what are ACE inhibitor side effects
- Cough
- Angioedema
- Potassium retention
what is given instead of ACE inhibitors
- Angiotensin receptor blockers (ARBs) have similar BP effects but are less likely to cause cough
describe the steps in renin angiotensin aldosterone BP regulation
- sympathetic nerve activation (acting through β1-adrenoceptors)
- renal artery hypotension (caused by systemic hypotension or renal artery stenosis)
- decreased sodium delivery to the distal tubules of the kidney
what is the mechanism of action of ACE inhibitors
- inhibit angiotensin II leads to vasodilation of small resistance arteries reduces the SVR and reduces the blood pressure
name the antihypertensive agents
- loop diuretics
- thiazides
- potassium sparing diuretics
describe the mechanism of action of loop diuretics
- inhibition of sodium potassium and 2 chloride symporter in the thick ascending limb of the loop of Henle, this inhibits the reabsorption of sodium potassium and chloride
name an example of loop diuretic
- furosemide – mainly used in heart failure
describe the mechanism of action of thiazides
- inhibit reabsorption of sodium and chloride ions for the distal convoluted tubules, block the sodium/chloride symporter
what is the first drug choice of thiazide
- first drug of choice is indapamide
what is bendroflumethiazide
Thiazides
describe the mechanism of action of bendroflumethiazide
- decrease intravascular volume reducing the cardiac output
- domaininat site of action is the distal tubule
- causes vasodilation and reduces the systemic vascular resistance
what is the mechanism of action of potassium sparing directions
- used in conjunction with other diuretics to prevent hypokalaemia
describe the mechanism of action of calcium channel blockers
- block calcium entry to vascular smooth muscle and myocardial cells this interrupts excitation and contraction coupling
dihydroprydine CCBs
- vasodilate dominant therefore reducing systemic vascular resistance
what is an example of an calcium channel blockers
amlodipine
what are side effects of calcium channel blockers
flushing headaches, odema
what is the action of non-dihydropyridine
- reduces heart rate, contractibility conduction – negative ionotropes and chronotropes
what is an example of a non-dihydropyridine
- example dilitiaxzem
what is a side effect of non-dihydropyridine
may worsen heart failure
what is the mechanism of action of NTG
- NTG causes nitrates to be taken up
- This causes increased production of nitric oxidise
- Leads to produce of GTP which actives cyclic GMP
- Leas to a lost of a phosphate from myosin
- This leads to vasodilation
what are the side effects of NTG
- Headache
- Dizziness
- Reflex tachycardia
what do low doses of NTG do
- Reduce preload
- Red myocardial oxygen demand
what do high doses of NTG do
- Reduce afterload
- Reduces myocardial oxygen demand
what is used to treat angina
beta blockers
what is the mechanism of action of beta blockers
- B1 RECEPOT ANTAGONIST
- Reduces heart rate and negative inotropic effect, this reduces blood pressure and myocardial oxygen demand
- These drugs work on multiple different pharmalogical receptors
what are the side effects of beta blockers
increases end diastolic volume and increases ejection time
what is the definition of after load
- Afterload: systemic vascular resistance (SVR), is the amount of resistance the heart must overcome to open the aortic valve and push the blood volume out into the systemic circulation
what are the symptoms of heart failure
- Breathlessness
- Ankle swelling
- Fatigue
what are the sings of heart failure
- Elevated jugular venous pressure
- Pulmonary crackles
- Peripheral oedema caused by structural and or functional cardiac abnormality resulting in a reduction in cardiac output and an +/- increase intracardiac pressures at rest or stress
what are the 3 types of heart failure
- Heart failure with reduce ejection fractions
- heart failure with mid range ejection fractions
- heart failure with preserved ejection fraction
what is an ejection fraction
Ejection fraction is a measurement of the percentage of blood leaving your heart each time it contracts
describe heart failure with reduce ejection fractions
there is a significant reduction of the left ventricular ejection function
describe heart failure with mid range ejection fractions
- Heart failure with mid range ejeulation fraction between 40-49%
describe heart failure with preserved ejection fraction
- Heart failure with preserved ejection fraction greater or equal to 50%
how did you work out the ejection fraction
- Amount of blood pumped out/total amount of blood in the chamber
what is the heart failure treat goal
The goals of treatment in patients with HF are to improve their clinical status, functional capacity & quality of life, prevent hospital admission & reduce mortality
how do you treat Heart failure with preserved/mid-range ejection fraction
- Screen patients for cardiovascular and non-cardiovascular comorbidities
- If present should be treated with effective interventions to improve symptoms
How do you treat Heart failure with reduced ejection fraction
- Use an ACE inhibitor
- Use an beta blocker – symptomatic patients
- Reduces the risk of hospitalisation due to heart failure and mortality
what are the three types of drugs used in heart failure
- positive inotropic drugs
- vasodilators
- miscellaneous drugs for chronic failure
name examples of positive inotropic drugs
cardiac glycosides
beta agonists
PDE inhibitors
name examples of vasodilators
PDE inhibitors
Nitroprusside Nitrates hydralazine
loop diuretics, ACE inhibitors
what are the two most common drugs used to treat angina
- vasodilators
- cardiac depressants
what are the two vasodilators
nitrates
calcium blockers
what are the 2 cardiac depressants
calcium blockers
beta blockers
