3.7 Cardiac Medications + Dental Side Effects Flashcards
What are the main drug classes used in hypertension medications?
- ACE inhibitors
- Angiotensin II anatgonists
- Calcium channel blockers
- Thiazide diuretics
- Beta blockers
What are the two types of antianginal medication?
- Nitrates
- Aspirin
Blood pressure is determined by cardiac output (stroke volume x heart rate) and peripheral vascular resistace. What are the targets for the various hypertension drug classes?
- Cardiac output (gen) = angiotensin II antagonists
- Stroke volume specific = diuretics + ACE inhibitors
- Heart rate specific = beta blockers
- Vascular resistance = calcium channel blockers
How do beta blockers lower heart rate?
Baroreceptor reflex compares arterial pressure to set point
When arterial pressure decreases, signals CNS to increase cardiac output via sympathetic pathway
Beta blockers prevent sympathetic pathway being activated
How do ACE inhibitors, angiotensin II antagonists, and diuretics lower heart rate?
Interrupt renin-angiotensin system (RAS) at various points
ACE inhibitors = inhibit angiotensin converting enzyme (ACE)
Angiotensin II antagonists = block angiotensin II (AT) receptors
Diuretics = prevent kidney from H2O + NaCl reabsorption
What are examples of ACE inhibitors?
“-prils”
Catopril, Enalapril, Fosinopril, Lisinopril
What are the cardio-renal effects of ACE inhibitors?
Vasodilation (arterial + venous) to reduce pressure and ventricular afterload + preload
Decrease blood volume
Inhibit cardiac + vascular hypertrophy
What are the side effects of ACE inhibitors?
Electrolyte disbalance
Worsen renal function (if already impaired)
Contraindicated in preganancy (2.7x risk of malformation)
Anaphylaxis
Dry cough
What are examples of angiotenin II antagonists?
“-sartans”
Losartan, candesartan, temlisartan
Calcium channel blockers block voltage dependent Ca2+ channels to relax vascular smooth muscle cells. What are examples of this type of medication?
Dihydropyridines (-dipine)
Amlodipine, Nifedipine, Felodipine, Nimodipine
Non-nihydropyridines
Diltiszam, verapamil
What are the desired effects of calcium channel blockers?
Cardiac = decrease contractility, heart rate, and conduction velocity
Vascular = smooth muscle relaxation
What are the side effects of calcium channel blockers?
Vasodilation (ankle oedema, tachycardia, headache, flushing)
Constipation
Verapamil/ciltizem can decrease cardiac output to point of heart failure
Gingiva hyperplasia
How do thiazide diuretics work to decrease blood pressure?
- Inhibit Na+ and Cl- reabsorption in distal tubule, decreasing body water retention + blood volume
- Direct effect on vascular smooth mucle = less responsive to vasoconstrictors
What are potential side effects of thiazide diuretics?
Gout
Hypercalcemia
Hypokalaemia
Hypomagnesemia
Hyperglycaemia
Electrolyte imbalance
Dry mouth
Noradrenaline causes both excitatory and inhibitory sympathetics responses due to different membrane receptor proteins. What are these different receptors and their effects?
Alpha-1 = vasoconstriction
Alpha-2 = negative feedback
Beta-1 = Increase heart rate + force of contraction
Beta-2 = relaxes bronchial + vascular smooth muscle
What are examples of beta blockers / beta-adrenoreceptor antagonists?
“-lols”
Atenolol, metoprolol, propanolol, pindolol, oxprenolol, sotalol, bisprolol
What are the two mechanims behind beta-adrenoreceptor antagonists?
- Decrease cardiac output by blocking B1 adrenoreceptors in heart
- Block CNS sympathetic outflow, inhibiting renin release (decreases peripheral resistance)
What are th epreferred beta-adrenoreceptor agonists for use, and why?
Cardio selective B1 blockers (atenolol / metoprolol)
Reduction in stroke / MI
Alone = 50-60% effective
With diuretic = 60-80% effective
What are possible side effects for beta-adrenoreceptor antagonists?
Bradycardia, reduced exercise capacity, heart failure, hypotension, and AV nodal conduction block
Asthamtic patient = bronchoconstriction
Diabetic patient = Hypotension from masking hypoglycemia
What are the common cholesterol lowering medications?
“Statins”
Atorvastatin, fluvastatin, pravastatin, rosuvastatin, simvastatin
How do statins lower cholesterol levels and what are the possible side effects?
Inhibits endogenous pathway of cholesterol synthesis
Common complaints = muscle pain
NOT SUITABLE FOR PREGNANT WOMEN
How are aspirins and NSAIDs used in patients with heart disease?
- Prevents arachidonic acid cycle creating COX
- Small doses block COX 1 = blocks thromboxane + prevent splatelet aggregation / blood clotting
What is the difference in effect between 100mg of aspirin and 300mg?
100mg = low dose, recommended for patients with previous cardiac issues eg angina
300mg at chest pain can prevent death + improve heart function immediately after MI
Possible side effects of NSAIDs are inducing asthma attacks or actuallay causing cardiovascular disease. What kind of NSAID would cause, rather than prevent cardiovascular disease?
COX 2 specific NSAIDs
COX 2 = anti-inflammatory effects
What are nitrates?
Nitrodilators are drugs that mimic the actions of Nitric Oxide (NO) by releasing NO or forming NO within tissues
What are the primary cardiovascular actions of nitrodilators (nitrates)?
- Vasodilation (decrease venous pressure + arterial pressure less so)
- Cardiac = reduced preload + afterload, decrease O2 demand
- Coronary = prevents vasospasm, vasodilation, improves subendocardial perfusion, and increase oxygen delivery
What are the possible side effects of nitrates?
Headache
Cutaneous flushing
Postural hyptension + reflex tachycardia
Adverse effect on cGMP-dependent phosphodiesterase inhibitors (erectile dysfunction meds)
