Introduction to cardiovascular drugs in dentistry Flashcards
Angina vs MI?
Angina = heart pain usually on exertion and will stop with meds and/or rest
lasts 15-30 mins
MI = more serious and can be spontaneous/not induced by exercise
lasts over 30 mins
Types of Cerebrovascular disease?
Transient ischemic attack
Thrombotic stroke
Vascular dementia
Common arrhythmias?
Atrial fibrillation
Healing process of healing in atherosclerosis?
Activation of platelets
Inflammatory cells - incorporation of cholesterol
Fibrous cap
Therapeutic targets for atherosclerosis?
reduce Wall stress (high bp) by targeting high BP
Inhibit platelets
Reduce cholesterol
What does aspirin inhibit?
Thromboxane A2
COX- 1
What does clopidogrel target?
ADP receptor antagonists
Dose of aspirin for stable angina pts?
75mg
Dose of aspirin after stroke or TIA/stroke?
300mg first 2 weeks after
If you take a pt of aspirin too early, what could this cause?
stent thrombosis
increase chance of MI
Implications of antiplatelts and dental therapy?
Interaction with NSAIDs
- potent COX inhibitors
- Increased bleeding - particularly GI tract
When to use beta blockers?
Reduce mortality in IHD and heart failure
Reduce symptoms of angina, AF and SVT
*Antihypertensive (2nd line now)- (multiple mechanisms of action both central and peripheral)
Do you use beta blockers for hypertension?
No
Examples of beta blockers?
Bisoprolol
Carvediol
Atenolol
Metoprolol
Propranolol
Where are beta I blockers located?
Heart - SA, AV nodes and myocardial cels
Kidneys - reduce secretion of renin
Where are beta 2 receptors located?
Smooth muscles e.g. airways, peripheral vasculature
Skeletal muscle
Positive effects of beta I blockers?
Slows heart rate and conduction
Reduced BP
Protects heart from effects of catecholamines
Increased diastolic time
Positives of beta 2 blockers?
Reduces tremors
Negative effect of beta I blockers?
Reduces contractility (negatively ionotropic)
BETA I blockers?
Bisopolol
Atenolol
Carvediol
Metoprolol
these inhibit beta 2 but not as prfound effect
Beta I and 2 blockers?
Propranolol
Implications of beta blockers in dentistry?
Protects heart from potentially deleterious effect of adrenaline
Can disguise physiological signs of significant blood loss
What is the first line of defence for hypertension in white/asian patient under 55?
ACE inhibitors
ARBS
Positive effect of ACE inhibitors?
Reduce blood pressuree
Reduce after load on heart
Prevents aberrant remodelling after mi
Reduces protienuria
Negative effects of ACE inhibitors?
Reduces perfusion pressure in glomerulus
- cough
Examples of ACE inhibitors?
Ramipril
Lisinopril
Captopril
Perindopril
Positive effects of ARBS?
Reduce BP
Reduce after load on heart
Presets aberrant remodelling and reduce proteinuria
Negative effects of ARBS?
Reduces perfusion pressure in glomerulus
What is the role of angiotensin II and what does angiotensin II act upon?
Postent vaoconstrictor
- peripheral vasculature
- efferent arteriole of the glomerulus
Role of aldosterone?
Retention of na (and therefore H20) at the expense of K in the DCT of the kidneys (sweat glands, duct)
Role of calcium channel blockers?
Antihypertensive agent
stop calcium from entering the cells of the heart and arteries. Calcium causes the heart and arteries to squeeze more strongly. By blocking calcium, calcium channel blockers allow blood vessels to relax and open.
What can calcium channel blockers reduce the symptoms of?
Angina
AF/SVT
2 classes of calcium channel blockers?
Non dihydropyridine and dihydropyridine
What does dihydropyridine block?
Calcium entry into smooth muscle
What does non-dihydropyridine block?
Blocks calcium entry into smooth muscle
Blocks calcium entry in the myocardial pacemaking tissue
- slow SA node function
- slow AV conduction
Implications for calcium channel blocker in dentistry?
Gingival hypertrophy -
particularly dihydropyridine
poor dental hygiene is a risk factor
What calcium channe blocker causes gingival hypertrophy?
Dihydropyridine
Types of ischaemic heart disease?
angina
MI
Coronary artery disease?
symptoms and damage of the heart muscle caused by narrowing of the blood vessels of the heart.
This leads to an imbalance between Oxygen demand and supply.
Causes of atherosclerosis?
high cholesterol and triglyceride levels, high blood pressure, smoking, diabetes, obesity, physical activity, and eating saturated fats.
What is the effect of atherosclerosis?
cardiovascular disease
it is central to these pathologies
Mode of action of aspirin?
Aspirin inhibits cyclooxygenase (mainly COX-1), resulting in a reduction of thromboxane A2, an inducer of platelet aggregation
irreversibly bind
effects lasts 7-10 days
What drug inhibits thrombin receptors?
vorapaxar
What drug is a fibrinogen receptor blocker?
abciximab
What is the main indication for aspirin, primary or secondary prevention?
secondary
after CVD diagnosis
Dose of aspirin after CABG?
75-150mg
When to use clopidogrel?
75mg after initial acute phase of tx or with aspirin
What should you need to control before the pt leaves the practice after an invasive technique (pt on blood thinners)?
haemostasis obtained
side effects of antiplatelest?
Bleeding
Roughly 0.25 to 1% annual risk of a significant bleed with a single agent,
synergistic effect when multiple agents used
Effect will last for up to 1 week.
NSAIDs and cardiovascular implications?
increased cardiovascular mortality in high risk patients and sodium retention in HF
What is meant by beta I blockers being negatively chronotropic?
reduce heart rate
Dromotropic (beta I blcokers)
increases rate of conduction through AV node
Negative effect of beta 2 blockers?
potentially lethal bronchospasm in asthmatics, vasoconstriction and PVD
The role of ACE inhibitirs and angiotensin receptor antagonsists?
- Antihypertensive- first line in under 55 White/ Asian patient
- Reduction in mortality and progression of disease in IHD, CVD and renal disease with proteinuria (particularly diabetic nephropathy)
- Prevent aberrant remodelling following MI
- Reduction in symptoms in heart failure
renin-angiotensin-aldosterone axis?
Renin enzyme released by the kidney in response to reduction in perfusion pressure
ACE isEndothelial enzyme found predominantly in the lungs
Aldosterone acts on the Distal Convoluted tubule to retain sodium and excrete potassium
Example of ARBS?
losartan, candersartan
Implications of ACE inhibitors and ARBS in dental practice?
Example of aldosterone antagonists?
Spironolactone and eplenerone
Implication for aldosterone inhibitors?
used in heart failure (frequently coprescribed with ACE/ARB).
Spiro sometimes used in hypertension
What aldosterone antagonsist is sometimes used in hypertension?
Spironolactone
What class of drugs should be used with great caution with aldosterone antagonists?
NSAIDS should be used with extreme caution- marked hyperkalaemia seen if AKI occurs
Effect of aldosterone antagonists?
Enhanced diuretic effect
Reduces mortality in IHD and Heart failure
What is entresto?
Combination of Valsartan and Sacubitril
What does sacubitril inhibit?
it is an entresto
Neprilysin Inhibitor
Effect of entresto?
- inhibits breakdown natriuretic peptides eg. ANP and BNP (and Bradykinins)
- increase diuresis, natriuresis and vasodilation
Indication for entresto?
- indicated in symptomatic chronic HF with reduced ejection fraction
What should you not co-prescribe entresto with?
- Do not co prescribe with ACE inhibitor (allow 36 hour washout period) as increased risk of angioedema
Key role of calcium in smooth muscle contraction?
Calcium key role in smooth muscle contraction- binding to contractile apparatus and activating enzymes
In cardiac muscle movement of calcium into cells contributes to the action potential- particularly important in the Nodal tissue of the AV node. Slow conduction within this tissue and prolongs effective refractory period.
dihydropyridine vs non-dihydropyridine?
dihydropyridine less effect on heart pace making tissue
non-dyhydropyridine does have effect on heart pace making tissue
- slow SA node function
- slow AV conduction
example of dihydropyridine and what class of drug is this?
Amlodipine, felodipine
calcium channel blocker
example of non-dihydropyridine and what class of drug is this?
Verapamil and Diltiazem
calcium channel blocker
When to use statins?
high level LDL (high cholesterol)
already had a heart attack or stroke, or have peripheral arterial disease.
When are statins the primary prevention?
reduce cardiovascular risk if patients 10 year risk is > 20%
When are statins the secondary prevention?
after cardiovascular event
How do statins work, what do they inhibit?
Hydroxy-methyl-glutaryl Coenzyme A (HMGCoA)reductase inhibitor
Rate limiting step in production of cholesterol
Examples of statins?
Simvastatin, Rosuvastatin and Atorvastatin
myositis?
condition which makes your immune cells attack your muscles
Implication of statins in dental practice?
Clarithromycin contraindicated with Simvastatin and increases risk of Myositis
Implication of diuretics in the dental practice?
Potentially nephrotoxic effect in combination with NSAIDs
Effects of diuretics?
Antihypertensive effects- Thiazides eg. Indapamide and Bendroflumethizide
Promote Sodium and Water loss in the kidney (also can lead to hypokalaemia)
How do thiazide diuretics work and what is their effect?
Act by blocking NaCl reabsorption in distal convoluted tubule of the kidney
Mild diuretic effect
Vasodilatory effect
Example of thiazide diuretics?
Indapamide, Bendroflumethiazide
Common side effects of thiazide diuretics?
- Electrolyte disturbance (Low Na and K in particular but also Hypercalcaemia)
- Hyperuricaemia (causing gout and increased Cardiovascular risk)
- Hyperglycaemia
- Dehydration, renal impairment
- Orthostatic Hypotension
How do loop diuretics work and what is their effect?
Act by blocking NaCl Reabsorption in the ascending limb of the loop of Henle
Intense diuretic effect
Pronounced vaso and venodilatory effect
Example of loop diuretics?
furosemide and bumetanide
Common side effects of loop diuretics?
Electrolyte disturbance (Low K, Na and Mg and Ca)
Dehydration, renal impairment
Orthostatic Hypotension
When to use Vit K antagonists eg Warfarin and DOACs?
Primary or secondary prevention in CVD associated with AF
Prosthetic valves
Other indications eg. Mural thrombus in severe heart failure
Implications of anti-coagulants?
Bleeding covered by Dr Khan
Interactions with antibiotics commonly used:
- Enhanced anticoagulant effect via inhibition cP450 eg. Clarithromycin, Azole anti fungals
- Reduced anticoagulant effect via induction of cP450 eg. Rifampycin
Antianginals?
Nitrates long and short acting
Nicorandil- can be associated with ulceration
Antihypertensive?
alpha blockers eg doxasocin
Antiarrythmics?
Digoxin
Amiodarone- theoretically reduces the toxic dose of Lignocaine