Study Set Content:
Drugs in this class may be less effective in the
elderly and in individuals of
• ()These differences are relatively
small and may not apply to an individual patient
African ancestry.
reduce the frequency
anginal episodes and improve exercise tolerance in
many patients with angina.
Beta-adrenoceptor blockers
These actions relate to the blockade of cardiac B
receptors, resulting in () cardiac work and
reduction in oxygen demand. Slowing and
regularization of the heart rate.
decreased
Studies indicate that the long-term use of () in patients who have had a myocardial infarction prolongs survival
timolol,
propranolol, or metoprolol
In this setting, relative contraindications include
() moderate or severe left
ventricular failure, shock, heart block, and active
airways disease.
bradycardia, hypotension,
are effective in the treatment of
both supraventricular and ventricular arrhythmias.
Beta antagonists
By increasing the atrioventricular nodal refractory
period, B antagonists ()ventricular response
rates in atrial flutter and fibrillat
slow
These drugs can reduce ventricular ectopic beats,
particularly if the ectopic activity s been
precipitated by
catecholamines
has antiarrhythmic effects involving ion
channel blockade in addition to its B-blocking
action.
Sotalol
Clinical trials have demonstrated that at least three
ß antagonists (), and
()-are effective in reducing mortality in
selected patients with chronic heart failure.
metoprolol, bisoprolol, carvedilol
Although administration of these drugs may worsen
acute congestive heart failure, cautious long-term
use with () increments in patients who
tolerate them may prolong life
gradual dose
Although mechanisms are uncertain, there appear
to be beneficial effects on myocardial remodeling
and in decreasing the risk of
sudden death
have been found to
increase stroke volume in some patients with
obstructive cardiomyopathy.
Beta-receptor antagonists
This beneficial effect is thought to result from the
() of ventricular ejection and ()
outflow resistance.
slowing , decreased
are useful in dissecting aortic
aneurysm to decrease the rate of development of
systolic pressure. Beta antagonists are also useful in
selected at-risk patients in the prevention of
adverse cardiovascular outcomes resulting from
non cardiac surgery.
Beta antagonists
A Systemic administration and Topical
administration of () reduce
intraocular pressure in patients with glaucoma.
B-blocking drugs
Reduced production of aqueous humor by the
ciliary body, which is physiologically activated by
cAMP
suitable for local use in the eye because they
lack local anesthetic properties.
Timolol
appear to have an efficacy
comparable to that of epinephrine or pilocarpine in
open-angle glaucoma and are far better tolerated by
most patients.
Beta antagonists
Timolol maximal daily dose applied locally ()
may be absorbed from the eye to cause serious
adverse effects on the heart and airways in
susceptible individuals
(1 mg)
