Drugs for Angina Flashcards
(45 cards)
CAD
obstruction of coronaries by atheromatous plaques
-high risk, moderate risk, low risk (no, no risk class)
RF for CAD
high bp, high LDL cholesterol, smoking
also- diabetes, overweight, poor diet, inactivity, excessive alcohol use
Angina pectoris
chest discomfort when amt of blood delivered to heart annot supply enough oxygen to satisfy myocardial requirement
-chest pain resulting from myocardial ischemia
Nitroglycerin
immediately relieves angina pain
Classic or atherosclerotic angina
atheromatous obstruction of large coronaries
especially with exercise
-tx with drugs or bypass, angioplasty
Prinzmetal angina
spasm or constriction in atherosclerotic coronary vessels
-relived by nitrates of CCBs
MI pathophys
imbalance between oxygen supply and demand
oxygen demand depends on
cardiac workload which is determined by
-contractility, heart rate, wall stress
main energy source in heart
fatty acid oxidation (requires more oxygen than glycolysis)
Trimetazidine
shifts myocardial metabolism towards greater use of glucose- reduce oxygen demand
-pFOX inhibitors
Increase O2 delivery through coronary blood flow which is
- related to perfusion pressure and duration of diastole
- inversely proportional to coronary vascular bed resistance
- damage to endothelium increases vascular resistance
agents decreasing O2 demand of heart
b adrenergic agonists, organic nitrates, CCB
agents increasing O2 supply
vasodilators, statins, anti thrombotics
drugs can relax vascular smooth muscles by
increasing cGMP
3 drug groups for use in angina
1) organic nitrates
2) CCB
3) b blockers
ranolazine
reduces intracellular calcium concentration and thus reduces cardiac contractility and work
-new drug recently approved for angina
trimetazidine
pFOX inhibitor- metabolic modulator inhibits fatty acid oxidation in myocardium
allopurinol
inhibits xanthine oxidase (contributes to oxidative stress and endothelial dysfunction)
-prolongs exercise time in pts with angina
ivabradine
direct bradycardic agents inhibit hyperpolarization activated sodium channel in SA node
Fasudil
Rho kinase inhibitors reduce coronary vasospasm in experimental animals
Nitrates in angina
Act on guanalyl cyclase to convert GTP–> cGMP which causes relaxation
short acting nitrates
amyl nitrate inhaled, sublingual nitroglycerin or isosorbide dinitrate
-acute events
long acting nitrate
nitroglycerine slow release or oral, isosorbide oral, isosorbide mononitrate oral (10 hrs)
- chronic tx
- can lead to tolerance; have 12 hrs every day w/o nitrate effect
Nitrates act by releasing
- NO
- vascular smooth muscle ccells are relaxed, but vasodilation are uneven
- Large veins markedly dilated, arterioles are dilated less