systemic drugs: cardiovascular Flashcards
for what 2 reasons will you need to know what systemic drugs a patient is taking during history and symptoms in an eye exam
- to get some extra information about the patients general health
- certain medications that people are taking have ocular adverse reactions
what are the 2 most prescribed categories for treating
- cardiovascular disease
and - central nervous system
what are the highest % categories of conditions where drugs are reported as causing ocular adverse effects
- cardiovascular disease
and - central nervous system
what are the 2 most common causes of death
- Cardiovascular disease (eg angina, MI)
and - Cerebrovascular disease (stroke)
what risk factors of cardiovascular diseases and cerebrovascular disease are non-modifiable
- age
- gender
- family history (genetic predisposition)
what risk factors of cardiovascular diseases and cerebrovascular disease are modifiable
- smoking (lifestyle issue)
- hypertension (can be modified pharmacologically)
- hyperlipidaemia/raised cholesterol (can be modified pharmacologically)
what is a normal BMI required in order to avoid cardiovascular diseases and cerebrovascular disease
20-25 Kg/m2
what is the required exercise type and frequency required to avoid cardiovascular diseases and cerebrovascular disease
regular aerobic physical exercise (brisk walking rather than weight lifting) for 30 minutes per day, ideally on most of days of the week but at least on three days of the week
what is the maximum required salt intake required to avoid cardiovascular diseases and cerebrovascular disease
6g/day
at what clinic blood pressure value systolic/diastolic required ambulatory blood pressure monitoring
140/90mmHg or higher
what is ambulatory blood pressure monitoring
issuing someone with a 24 hour blood pressure monitor as this will periodically check blood pressure and monitor it over 24 hours before making a prescribing decision
this is done in order to confirm the diagnosis of hypertension
when must you act upon controlling someones blood pressure immediately
if the blood pressure causes damage to organ tissues
what does the national clinical guidance centre NCGC on hypertension clinical guideline contain
an algorithme structure on the diagnosis of hypertension and how to monitor that patient
what are the only 2 bits if information needed to determine someones risk of having a CV event in the next 10 years
- the systolic BP
and - the ratio between total cholesterol and HDL cholesterol
what does total cholesterol contain
three types of lipid measurements
- LDL
- HDL &
- Triglycerides
which is the bad lipid
LDL
which is the good lipid
HDL
which is the in-between LDL and HDL lipid
triglycerides
what are the 2 main reasons for treating hypertension
- Reduce cerebrovascular disease by 40-50%
- Reduce MI by 16-30%
by how much does hypertension treatment reduce cerebrovascular disease by
40-50%
these are relative risk reductions so if your chance of developing a heart attack within 10 years is 5% the its going to take your risk from 5% down to 2.5%
by how much does hypertension treatment reduce MI by
16-30%
which 2 ways is best to treat hypertension and why
- Stepped approach: start with a first line drug and if that does work then combine the drugs
- Use low doses of several drugs
This approach minimises adverse events and maximises patient compliance
what is the main aim of hypertension treatment
- To reduce diastolic BP to
what do the NICE guidelines on hypertension state about those who have it aged below 55 y/o
they must be put straight on ACE inhibitor
what do the NICE guidelines on hypertension state about those who have it aged above 55 y/o
they must be put on a calcium channel blocker and a thiazide type diuretic
what do the NICE guidelines on hypertension state about those who are of black ethnicity and have it
they must be put on Thiazide which is a type of diuretic
as ACE inhibitors are contraindicated in black people
why are black people who have hypertension put on Thiazide which is a type of diuretic
as ACE inhibitors are contraindicated in black people
what do the NICE guidelines suggest if individual drugs don’t work
use an adaptive approach
which is the most common drug to treat hypertension
ACE inhibitors
how do ACE inhibitors work in treating hypertension
by competitively inhibiting the angiotensin converting enzyme (ACE)
what does the angiotensin converting enzyme (ACE) do
it converts angiotensin I to active angiotensin II
what is angiotensin II
it is a potent vasoconstrictor therefore it raises blood pressure
therefore you want to prevent the formation by blocking the enzyme that converts into this in order to lower BP
name 4 examples of ACE inhibitor drugs
- Captopril
- Enalapril
- Lisinopril
- Ramipril
all end in pril
which drugs all end in ‘pril’
ACE inhibitor drugs - to reduce hypertension
list 5 side effects of ACE inhibitor drugs
- Cough (15% of patients)
- Taste disturbance
- Angiodema
- First-dose hypotension (lowers BP too much)
- Hyperkalaemia (raised potassium)
how do Angiotensin II receptor antagonists (blockers) reduce hypertension
by competitively inhibit the receptor at which angiotensin II acts
it achieves its effects by binding onto a Angiotensin II receptor
what is the advantage of Angiotensin II receptor antagonists (blockers) drugs
it has fewer side effects than ACE inhibitors
name 3 examples of Angiotensin II receptor antagonists (blockers) drugs
- Candesartan
- Losartan
- Valsartan
all end in ‘artan’
what do all of Angiotensin II receptor antagonists (blockers) drugs end in
‘artan’
how do calcium channel blockers reduce hypertension
they all inhibit inward movement of calcium ions through the slow L-type calcium channels in active membranes: - Cells of the myocardium
- Cells within the His-Purkinje system of the heart
- Cells of vascular smooth muscle
and
- Cause vasodilation of large and small arteries and also reduce cardiac output/total peripheral resistance
this affects cardiac contractility and causes vasodilation
which three active membranes do calcium channel blockers inhibit the inward movement of calcium ions through the slow L-type calcium channels
- Cells of the myocardium
- Cells within the His-Purkinje system of the heart
- Cells of vascular smooth muscle (reduces vasoconstriction)
what 2 things are calcium channel blockers useful in the treatment of
hypertension and angina
name 4 examples of calcium channel blockers
- Nifedipine
- Amlodipine
- Verapamil
- Diltiazem
how do diuretics reduce hypertension
by promoting the excretion of water
where in the body do diuretics act on
on the kidney and in particular at different sites of the nephron by blocking the ion channels
at the nephron is where ions are taken out of the system and whenever you move ions, water follows with it and this is how urine is less watery and more concentrated
what happens if you were to block the ion channels which is what diuretics do
the water is retained and not moved out with the ions, so there is more water and more excretion of urine which reduces the blood volume
= the drug has a two fold action
name 3 classes of diuretic
- Thiazides
- Loop diuretic
- Potassium sparing
how does the thiazides class of diuretic work
Inhibit absorption of sodium in the DCT
what can the class of diuretics, thiazides lead to
potassium deficiency
how does the class of diuretics, thiazides reduce BP
by:
- Vasodilation
- Reduction in blood volume
name 3 examples of class of diuretics, thiazides
- Bendrofluazide
- Hydrochlorthiazide
- Indapamide
all end in ‘azide’ mostly
what do most diuretics, thiazides end in
‘azide’
which is the most commonly used diuretic
thiazides
how does the loop class of diuretic work
Inhibit absorption of sodium and potassium in TAL of loop of Henle
what is an advantage of the loop class of diuretic
it is fast acting
when is loop class of diuretic mostly used
in renal failure and heart failure
give 2 examples of loop class of diuretic
- Furosemide
- Bumetanide
as diuretics tend to cause potassium depletion, name a class of diuretic that retains potassium
potassium sparing
were do potassium sparing class of diuretics act
at DCT
what is potassium sparing class of diuretics used in conjunction with and why
thiazide and loop diuretic classes, incase potassium levels become a problem
name 2 examples of potassium sparing class of diuretics
- Amiloride
- Spironolactone
which drug performs the least well than other drugs for hypertension
beta blockers
what are beta blockers used in the treatment of
angina
what do beta blockers have increased risk of
side effects
name 2 examples of beta blockers
- Atenolol
- Metoprolol
end in ‘ol’
what do beta blocker drugs tend to end in
‘ol’
how do beta blockers work
Mechanism of action is unknown but may involve:
- Reduction of heart rate and force of contraction
- Reduction in peripheral resistance
- Inhibition of renin release
- Central actions to reduce sympathetic activity
list 3 classes of drugs less commonly used as anti-hypertensive agents
- Alpha-adrenoceptor antagonists
Doxazosin - Centrally acting agents
Methyldopa
Moxonidine - Vasodilators
Hydralazine
Minoxidil
list 3 other types of cardiovascular disease
- Ischaemic heart disease
- Cardiac failure
- Cardiac arrythmias
what is another name for ischaemic heart disease
Angina Pectoris
what symptoms does ischaemic heart disease (Angina Pectoris) present with
intermittent chest pain on exertion or stress (‘stable’ angina)
at rest, there are no symptoms, but get chest pain on exertion e.g. climbing up the stairs etc
what is ischaemic heart disease (Angina Pectoris) caused by
by insufficient oxygen supplied to cardiac muscle due to narrowing of coronary arteries
how is a single acute attack of ischaemic heart disease (Angina Pectoris) treated
by a Glyceryl trinitrate-potent vasodilator
given in patch form absorbed across the skin, or put tablet under tongue so its absorbed by oral mucosa
why is Glyceryl trinitrate-potent vasodilator used to treat a single acute attack of ischaemic heart disease (Angina Pectoris) not given in tablet form
because once the drug is given in tablet form they’re broken down before they get into the blood stream and then the drug is inactivated
so is given as patch form absorbed across the skin, or put tablet under tongue so its absorbed by oral mucosa
what is given as a prophylaxis for ischaemic heart disease (Angina Pectoris) and what else should all patients receive along with this
- Sublingual GTN
- Aspirin
- Beta- blockers
- calcium channel blockers
All patients should receive lipid lowering therapy (to avoid atheroma formation)
what are the signs of Ischaemic Heart Disease:Myocardial Infarction
ST elevation on ECG
ST = flat segment on an ECG, follows the S wave and before the start of the T wave
what are the 3 immediate treatments used for Heart Disease:Myocardial Infarction
- Analgesia
- Thrombolysis
- Aspirin
why is thrombolysis given immediately after a Myocardial Infarction
to avoid damage of myocardial tissue, given as an injection to immediately dissolve the clot and limit any damage caused
why is aspirin given immediately after a Myocardial Infarction
as it stops platelet aggregation
why is analgesia given immediately after a Myocardial Infarction
to control the chest pain
what 4 drugs are given as prophylaxis for Ischaemic Heart Disease:Myocardial Infarction
- Beta blockers
- ACE inhibitors
- Aspirin
- Lipid lowering therapy
then they’re put on maintenance therapy, not to treat the heart attack, but to prevent a subsequent one
what is heart failure the result of
damage to the myocardium e.g. MI, myocardiomyopathy, heart valve damage
what does heart failure result in
poor tissue perfusion and oedema of the lungs or peripheral tissues
what are the 5 treatments for heart failure
- Diuretics
- ACE inhibitors
- Nitrates
- Beta blockers
- Ionotropic drugs e.g. Digoxin
what happens in oedema in the lungs
it is from pulmonary oedema
where it retains fluid within the lungs and also when the heart valves don’t work efficiently
what are cardiac Arrhythmias and why do they happen
- they’re heart rhythm disorders - arterial fibrillation is a major risk factor for heart attacks
- it happens because the atria don’t contract fully and small clots form which when expelled from the heart, they go onto block blood vessels in the heart or brain
what 2 drug therapies is used to treat Supraventricular tachycardia
- Adenosine
- Verapamil
what 3 drug therapies is used to treat Arrhythmias caused by Wolf-Parkinson-White Syndrome
- Amiodarone
- Disopyramide
- Flecainide
what 3 drug therapies is used to treat Atrial fibrillation
- Digoxin
- Disopyramide
- Amiodarone
what 2 drug therapies is used to treat Ventricular tachycardia
- Lidocaine
- Amiodarone
what do all the different drugs taken for Cardiac Arrhythmias result in
changes in the cardiac action potential
what drug will many patients over 50 be taking
statins
what 2 drugs will every T2 diabetic patient be taking
- statins
and - BP lowering medications
where are cholesterol and triglycerides are transported
in the blood from the liver in association with lipoproteins:
- Very low density lipoprotein (VLDL)
- Low density lipoprotein (LDL)
- High density lipoprotein (HDL)
what is LDL cholesterol particularly associated with
atheroma and cardiovascular disease
which lipoproteins do statins target
LDLs
what does lowering LDL cholesterol by 1mm/ol result in
reduces CVD events by 21% and total mortality by 12%
what is the Lipid modification: NICE guidance and what does it tell you
- its an algorithm for lipid control
- tells you what to do if a px falls into a category
what produces cholesterol in the body
HMG-CoA reductase - enables the cell to make cholesterol
cholesterol is then released into the blood
how do cholesterol lowering statins work
by inhibiting HMG-CoA reductase
cholesterol levels is blocked, lowering levels of cholesterol in the blood by increased uptake of LDL from the by the cell (which takes on more of the cholesterol)
name 3 examples of statins
- Simvastatin
- Atorvastatin
- Pravastatin
explain the mechanism of how lower intracellular levels of LDL occur
by taking in more LDL from the blood
this is done by blocking the enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase = the rate-limiting step in cholesterol biosynthesis, causing lower LDL levels whereby the cell puts more LDL receptors on its surface and pulls all of the cholesterol out of the blood/plasma
other than statins, name 4 other lipid lowering drugs
- Fibrates
- Anion exchange resins
- Ezetimibe
- Nicotinic acid
list all the 6 main drug categories involved in lowering the risk of cardiovascular disease/cerebrovascular disease
- ACE inhibitors
- Angiotensin II receptor antagonists
- Calcium Channel blockers
- Diuretics
- Beta blockers
- Statins
what is the maximum alcohol consumption required for men to avoid cardiovascular diseases and cerebrovascular disease
what is the maximum alcohol consumption required for women to avoid cardiovascular diseases and cerebrovascular disease
list the 9 lifestyle measures needed to avoid cardiovascular disease
- stop smoking
- maintain normal weight for adults (BMI 20-25kg/m2)
- reduce salt intake to 30 mins per day, atleast 3 days per week
- consume atleast 5 portions/day of fresh fruit and veg
- reduce intake of total saturated fat
