ANGINA Flashcards
t or f
ischemia is a symptom of angina
t
Regional flow distribution is improved by _________,____,_______
nitrates, ccb, b blockers
coronary blood flow is increased by____,____
nitrates, ccb
Heart rate and cardiac contractility is decreased by
b-blocker, CCB
Drugs that reduce cardiac size (the preload and
afterload), rate, or force reduce cardiac oxygen demand
Vasodilators, Beta blockers, Calcium channel blockers
Drugs that block________ can indirectly reduce
calcium influx and consequently reduce cardiac
contractile force
late sodium current
Drugs that shift myocardial metabolism towards greater
use of glucose
fatty acid oxidation inhibitors
determines left ventricular systolic wall stress
Arteriolar tone
Determine right ventricular diastolic wall stress
Venous tones
Calcium- calmodulin complex
Prevent mlck
Sildenafil will inhibit ____
Pde
Most prevalent form of angina pectoris
stable angina
with myocardial 02 demand
stable
without increase in myocardial O2 demand, with coronary thrombosis
unstable or ACS
local vasospasm
variant/prinzmetal
Tx for variant angina
Nitrovasodilators and ccb
Drug-induced causes of variant angina
Cocaine, amphetamines,sumatriptan, antimigraine
2nd line of defense (unstable angina)
nitrates
Coronary micro-vascular dysfunction
No obstruction
activates the soluble isoform of guanylyl cyclase
Nitric oxide (organic nitrates)
Preferentially dilates veins and conductance
arteries and leave the tone of the small to
medium arterioles (that regulate resistance)
unaffected
low doses
Preferential venodilation decreases venous
return, leading to a fall in left and right ventricular
chamber size and end-diastolic pressures,
reduced wall stress, and thereby reduced cardiac
O2 demand
▪ Heart rate remains unchanged or may increase
slightly in response to a decrease in blood
pressure
▪ Pulmonary vascular resistance and cardiac
output are slightly reduced.
▪ They may still produce arteriolar dilation in the
face and neck, resulting in facial flush or dilation
of the meningeal arterial vessels, causing
headache.
low to medium
Increase venous pooling and decrease arteriolar
resistance, thereby decreasing systolic and
diastolic blood pressure causing pallor,
weakness, dizziness, and activation of
compensatory sympathetic reflexes
▪ It can compromise coronary flow and sympathetic
increase in myocardial O2 demand leading to
ischemia
▪ May produce Bezold-Jarisch reflex with
sublingual administration producing bradycardia
and hypotension
higher doses (nitrates)
worsen the perfusion of ischemic areas by dilating the relatively constricted arterioles of the healthy myocardium, leading to redistribution of decrease angina threshold in the interval
blood flow away from the ischemic myocardium
(“Steal Phenomenon”)
Non-selective vasodilator ( adenosine or dipyridamole)
X therapeutically
✅ stress test
Dipyridamole
Tolerance to nitrates
Loss of response, decrease angina threshold
Organic nitrate dependence, workers exposed to GTN
Monday disease
Hours to return the nitrate efficacy, to prevent tolerance
8 to 12 hours
Px with exertional dyspnea
Most convenient: at night
Px with anginal pattern assoc.by increase in left ventricularfilling pressures
Nitrates at night
also approved in patients with
pulmonary hypertension by decreasing
pulmonary vascular resistance and enhanced
exercise capacity.
Sildenafil
Nitrate response
Veins > arteries
Nitrates indirect effect
Dec arterial pressure, tachycardia, inc contractility
Verapamil acts on
L-type
T or F
CC B do not affect Cardiac preload significantly when given at normal doses
t
Reynauds phenomenon
Felodipine, Nifedipine, Diltiazem, Verapamil
▪ Reduces slow inward current in a dose
dependent manner, it does not affect the rate of recovery of the slow Ca+ channel
▪ It has clear negative chronotropic effects in
isolated preparation (demand is decreasing)
▪ Does not directly affect pacemaking or
conduction of AV node rather it stimulates the
heart indirectly by eliciting reflex sympathetic
activation in response to a lowering of blood
pressure
Nifedipine
Not only reduces the magnitude of the Ca+ entry
current through the slow channel, but also decreases the rate of recovery of the channel.
stimulation
prevails
▪ Depress the rate of the sinus node pacemaker
and slow AV conduction at clinically used doses; the latter effect is the basis for their use in the treatment of supraventricular tachyarrhythmias
▪ It improves left ventricular outflow obstruction
and symptoms in patients with Hypertrophic cardiomyopathy because there is negative inotropic effect.
▪ Use prophylaxis for migraine headaches and
considered as second choice
verapamil
Px with neurological deficits secondary to cerebral vasospasm
nimodipine
In patients without heart failure -_________
o reduces peripheral vascular resistance and
blood pressure with minimal changes in heart rate.
o Ventricular performance in not impaired
and actually may improve, especially if ischemia limits performance
VERAPAMIL
In patients with heart failure -_______
o can cause marked decrease in contractility
and left ventricular function. it is primarily as with all Ca+ channel blocker to a reduction in myocardial O2 demand. amlodipine and felodipine did not worsen the prognosis of patients with heart failure and can therefore administered if indicated for other reasons
IV VERAPAMIL
Ccb toxicity
peripheral edema (inc hydrostatic pressure
effects of CCBs in cardiac muscle
dec contractility and heart rate
Only drug class that is effective in reducing the severity and frequency of attacks of exertion or effort angina and in improving survival in patients who have had a myocardial infarction.
bblockers
Increased blood flow towards ischemic regions by
increasing coronary collateral resistance and
preventing blood from being shunted away
from the ischemic myocardium during maximal
coronary vasodilation,
REVERSE STEAL OR
ROBIN HOOD PHENOMENON
for steal phenomenon
nitrates
1st line tx for CAD, not useful for vasospastic angina
bblockers
Standard compounds for the
treatment of angina are beta 1
selective and without intrinsic
sympathomimetic activity
BETA 1 SELECTIVE (ATENOLOL,
BISOPROLOL, METOPROLOL)
may be va,uable in treating silent ischemia, total ischemic time is reduced with long term use of this
beta blockers
balance effect of increase in end diastolic volume and inc ejection time in bblockers
nitrates
inhibits the late lNa, → and there an
interplay in the NCX, → decreasing the calcium
overload → Reducing and relaxing diastolic
wall stress → Reduces myocardial ischemia
Ranolazine
Reduces cardiac fatty acid oxidation and stimulates glucose metabolism without inhibiting carnitine palmityl transferase
ranolazine
Prolongs the QT interval but shortens in patients with long QT syndrome, LQRT3
ranolazine
Treating stable angina and heart failure in
patients with whom beta blockers are not
tolerated or are insufficiently effective in
reducing the heart rate and FDA approved only
for the treatment of heart failure
Ivabradine
Selective blocker of hyperpolarization- activated HCN ion channels involved in the
generation of automaticity in the SA node
Ivabradine
tx of stable angina, with nitrate-like effects and acts as an agonist at ATP sensitive potassium channels
nicorandil
side effects of nicorandil
Large painful buccal apthosis and risk of GI
ulceration and perforations
Inhibition of long chain 3 ketoacyl
coenzyme A thiolase, the final enzyme in the
FFA beta oxidation pathway
trimetazidine
Reduce angina and increase exercise
tolerance particularly in patients with
diabetes and heart failure
trimetazidine
▪ Associated with thrombocytopenia,
agranulocytosis, and liver dysfunction ▪ Increase risk of movement disorders such as
Parkinson’s disease, particularly in older
patients with decreased renal function
trimetazidine
Abandoned due to reports of hepatotoxicity and
▪ Shift myocardial metabolism from fatty acid oxidation to more efficient glucose oxidation
Perhexiline
inhibitor of smooth muscle Rho Kinase and
reduces coronary vasospasm in experimental
animals
Fasudil
medications for microvascular angina
o BB o CCB o Nicorandil o Ranolazine o Ivabradine o Trimetazidine
medications for vasoplastic angina
CCB, long acting nitrates, nicorandil
At low doses 75 to 150 mg/day reduces incidence
of clinical events.
aspirin
was slightly superior to aspirin in patients with
chronic atherosclerotic vascular disease and had
a favorable safety profile
clipidogrel
Unclear benefits in patients with CAD when given
routinely in addition to aspirin, statins, and beta
blocker but they are recommended for subgroups
with CAD with reduced left ventricular systolic
function, hypertension, diabetes or chronic kidney
disease. If you have a patient with HF or angina
you have to give this.
aceis/ arbs
