Treatment of Angina Flashcards
- high blood pressure
- high LDL cholesterol
- smoking
- diabetes, obesity, poor diet, physical inactivity, excessive alcohol use
- risk factors for?
CAD
- characterized by chest discomfort when amt of blood delivered to heart by coronary arteries cannot supply enough oxygen to satsify the myocardial requirement
- immediate relief - organic nitrates
- prophylaxis: CCBs and beta blockers
angina pectoris
- atheromatous obstruction of large coronary arteries, esp with exercise
- if uncontrolled by drugs may require coronary bypass or angioplasty
classic or atherosclerotic “angina of effort”
- spasm or constriction in atherosclerotic coronary vessels
- relieved by nitrates or CCBs
variant/angiospastic/Prinzmetal’s angina
- imbalance between oxygen supply and oxygen demand by myocardium
- oxygen demand depends on cardiac workload determined by contractility, HR, wall stress
- frequently during exercise or sympathetic discharge
myocardial ischemia
- main source of energy in heart is fatty acid oxidation
- drugs like ________ shift myocardial metabolism towards greater use of glucose, a pFOX inhibitor
trimetazidine
reduces intracellular calcium concnetration and reduces cardiac contractility and work
ranolazine
inhibits xanthine oxidase (which contributes to oxidative stress and endothelial dysfunction, high dose prolongs exercise time in patients with angina
allopurinol
amy nitrite, sublingual nitroglycerin, and sublingual isosorbide dinitrate are ______ nitrates used for angina
short acting
oral nitroglycerin, buccal nitroglycerin, oral isosorbide dinitrate and mononitrate are _______ nitrates
long acting
nitrates preferentially dilate _______
large veins
other effects of NO:
- ______, a PDE-5 inhibitor, can potentiate action of NO in angina, cause severe hypotension
- increased cGMP in platelets ______ aggregation
- nitrite ion reacts with hemoglobin to produce ________, which can be used to treat cyanide poisoning b/c it regenerates cytochrome oxidase
sildenafil
decrease
methemoglobin
harmful nitrate effects:
- reflex increases in HR and contractility _______ myocardial O2 demand
- reflex tachy causes ______ perfusion due to shorter _______
increase
decreased, diastole
nitroglycerin and isosorbide dinitrate are preferred sublingual for rapid absorption and to avoid __________
hepatic destruction
IV sodium nitroprusside dilates _________ evenly
arteries and veins
- acute nitrate toxicity can cause strong vasodilation leading to ______ and _____
- Monday disease - tolerance diminishes on weekend, headache and dizziniess upon reexposure
orthostatic hypotension, tachycardia, headaches
- orally active drugs that block L type channels in myocardium and vascular smooth muscles
- arterioles more sensitive than veins
CCBs
verapamil has most sensitivity for _____ muscle and nifedipine has strongest selectivity for _______ muscle
cardiac
vascular smooth
- decrease contractility, reduce SA node impulse generation, slow AV node conduction
- ________ most likely to produce reflex tachycardia
- _______ most likely to cause myocardial depression
CCBs
nifedipine
verapamil
- inhibition of insulin secretion
- interference with platelet aggregation
- flushing, dizziness, constipation
- reduce digoxin clearance
CCB side effects
- decrease sympathetic tone to decrease cardiac output
- reduce myocardial oxygen requirements at rest and during exercise
b-blockers (atenolol, metoprolol, propanolol)
- have been shown to reduce mortality in patients with MI, improve survival and prevent stroke in hypertensive patients
- do not dilate coronary arteries
- bradycardia prolongs diastole and increases myocardial perfusion time
- may induce or worsen CHF
beta blockers
treatment of angina pectoris in a patient with hypertension?
monotherapy with slow release CCB or beta blocker
treatment of angina in normotensive patient?
long acting nitrates
