Pharmacology of Stable CAD Flashcards
What is atypical angina?
Stable angina, with not clearly identifiable symptoms compared to ischaemic chest pain (SOB, burning, reflux).
What are the characteristics of stable angina?
Predictable - caused by exertion, improved with rest.
Consistent - similar frequency, intensity, and duration of episodes.
Relieved by medication - effective in both preventing and resolving.
Not an emergency - uncomfortable, but does not require medical attention.
What is the treatment of stable CAD?
Relieves symptoms - reducing demand and improving coronary blood flow.
Slows or halts the disease process.
Prevents MI and premature death.
What is the pharmacology of stable CAD?
Rate limiting - BBs, CCBs.
Vasodilators - nitrates, K+ channel activators.
Ranolazine - Na+ channel activators.
Antiplatelets - aspirin, clopidogrel, ticagrelor.
Cholesterol-lowering drugs - HMG-CoA reductase inhibitors, fibrates.
What are beta blockers?
A reversible inhibitor of B1 and B2 receptors.
Cardio-selective - bisoprolol, metoprolol, atenolol.
Non-selective - carvedilol, propranolol.
What are the cautions, side effects, and benefits of beta blockers?
Cautions - asthma, acute heart failure, bradycardia, heart block, PVD.
Side effects - fatigue, impotence.
Benefits - reduces HR and workload, improves relaxation, increases diastolic perfusion time, and reduces the rate of ischaemia and mortality.
What are CCBs?
Prevents Ca2+ influx into myocytes and smooth muscle arteries and arterioles.
Dihydropyridines (DHPs) mostly relax smooth muscle - amlodipine, felodipine, nifedipine.
Non-dihydropyridines (N-DHPs) mostly reduce HR - verapamil, diltiazem.
What are the cautions, side effects, and benefits of CCBs?
Cautions - bradycardia and heart block (N-DHP), peripheral oedema (DHP), hypotension (both).
Side effects - reduced LV function, headache.
Benefits - reduces HR, contractility, and increases diastolic perfusion time (N-DHP); reduces afterload (DHP).
What are nitrates?
Mediates non-selective smooth muscle relaxation.
Cautions - severe aortic stenosis.
Side effects - hypotension, headache.
Benefits - reduces preload and afterload, improves coronary flow (vasodilation). Doesn’t reduce mortality.
What is Nicorandil?
A K+ channel activator (inhibits Ca2+ influx).
Cautions - GI ulceration.
Side effects - hypotension.
Benefits - smooth muscle relaxation.
What is Ivabradine?
2nd line (rate limiting) - inhibits ‘funny’ channels in SAN (only works if sinus rhythm).
Cautions - SAN disease.
Side effects - bradycardia.
Benefits - reduces HR and rates of infarction.
What is Ranolazine?
Inhibits late Na+ current in myocardial cells and rapid phase of late K+ current (reduces intracellular Ca2+).
Cautions - use with CYP enzyme inhibitors.
Side effects - prolongs QT interval.
Benefits - reduced wall stress (easier to perfuse microcirculation, reduced O2 demand).
What are examples of cholesterol-lowering drugs?
HMG-CoA reductase inhibitors - atorvastatin, simvastatin, rosuvastatin.
Fibrates - bezafibrate, fenofibrate.
Ezetimibe - inhibits cholesterol uptake in the gut. The liver increases uptake from the blood, lowering LDL. Often used with a statin.
What are the benefits of cholesterol-lowering drugs?
Reduced rate of MI.
Plaque stabilisation.
Reduces LDL.
Increases HDL.
What are antiplatelets?
Aspirin, Clopidogrel, Ticagrelor - inhibits platelet activation via cellular pathways.
Aspirin is no longer recommended due to associated GI bleeding. Reduces adverse cardiac events when used correctly.
