Antianginal Drugs

Question 1

most common factors that reduce supply of oxygen to myocardium

Answer 1

1) occlusive coronary artery lesions due to atherosclerosis

2) reversible narrowing due to coronary spasm or thrombi

Question 2

Classic Angina ( angina of effort or exercise )

Answer 2

due to to coronary atherosclerotic occlusion

Question 3

Variant angina ( Prinzmetal )

Answer 3

due to reversible decrease in coronary blood flow

Question 4

Unstable Angina ( crescendo )

Answer 4

presents acute coronary syndrome with platelet aggregation

Question 5

NO has been identified as

Answer 5

the endogenously released endothelium - derived relaxing factor

Question 6

The formation of NO in endothelial cells can be triggered by

Answer 6

1) Ach
2) bradykinin
3) histamine
4) serotonin

Question 7

Nitrates pathway

Answer 7

Nitrates -> S-nitrosothiols : are releasing NO which activates -> guanylyl cyclase within the the smooth muscle cell to form -> cGMP which effects -> relaxation of vascular smooth muscle

Question 8

Nitrates from NO

Answer 8

1) causing marked dialtion of large veins -> decreasing of PRELOAD + CARDIAC WORK + DECREASE CARDIAC OXYGEN REQUIREMENT

2) Nitrates also improve collateral blood flow
3) Decrease coronary vasospasm
4) Inhibit platelet aggregation
5) At high doses , nitrates cause arteriolar dilation + decrease cardiac AFTERLOAD + cardiac oxygen requirement

Question 9

Nitrates decrease _____ and _____

Answer 9

1) infarct size

2) post-MI mortality

Question 10

Nitrates are considered as _____ and/or as ____ of ___

Answer 10

1) crisis therapy
2) prophylactic treatment
3) cardiac angina

Question 11

When does tolerance to the effect of nitrates occur?

Answer 11

It occurs when chronic therapy is considered ( mainly for long acting preparations ) . Considering that , the current recommendation is to provide a nitrate free interval of 8-12 hours daily to prevent tolerance.

Question 12

Side effects of nitrates

Most important

Answer 12

1) Hypertension
2) Headaches ( occurs at therapy initiation or in case of dose increase + decrease significantly after 1-2 weeks of therapy due to physiological tolerance ).

Question 13

Other side efects of nitrates

Answer 13

3) flushing
4) reflex tachycardia
5) fluid retention ( possibly counteroroductive )
6) tachyphylaxia - require ‘’ rest periods ‘’ of more than 12 hours
7) methemoglobinemia ( more likely with nitrites , e.g , amyl nitrite )

Question 14

How do the Calcium Channel blocking drugs act ?

Answer 14

they act by blocking of L and T type of membrane voltage activated calcium channels

Question 15

Dihydropyridines ( e.g Nifedipine as slow release forms , amlodipine )

Answer 15

1 ) are largely vascular selective

2) Are used as prophylactic therapy in all types of cardiac angina and also as anti-HTN medication , treatment of migraine headaches and Raynaud’s disease
* * In prophylactic treatment of cardiac angina are administered orally

Question 16

Side effects of Calcium Channel blocking drugs

Dihydropyridines

Answer 16

1) Hypotension
2) Reflex cardia tachycardia
3) Peripherical edemas
4) Headache
5) Constipation can be mentioned

Question 17

Verapamil
Diltiazem
imropve oxygen delivery by

Answer 17

1) dilating coronary arteries and coronary resistance vessels
2) Reduce oxygen demand by reduction of heart rate and afterload
3) Produce vasodilation but also
4) Block Ca channels in the heart
5) Reduce cardiac output

They are less indicated as antianginal medication

Question 18

Side effects of Calcium Channel blocking drugs
Verapamil and Diltiazem
( possible side effects that can be added to those associated to dihydropyridines treatment )

Answer 18

1) Severe bradycardia
2) AV block
3) Aggravation of congestive heart failure ( due to inotropic negative effect )

Question 19

Beta Blockers

Answer 19

1) No direct actions on vascular smooth muscle in angina
2) act directly on the heart reducing : HR , force of contraction , and CO , oxygen requirement
3) Effectively prophylactically in angina of effort ( not vasospastic ) and offset reflex tachycardia caused by nitrates
4) are used also to treat hypertension and as antiarrythmic medication

Question 20

Beta blockers act as

Answer 20

1) Beta receptors antagonists
2) competitive inhibition of the effect of circulating and locally released catecholamines.
3) Most beta blockers have been used (for other characteristics see sections on autonomic drugs and antihypertensive drugs).

Question 21

beta blockers that are used as antianginal treatment

Answer 21

1) Non-selective beta blockers (propranolol), selective beta1 blockers (atenolol, metoprolol) and
2) beta blockers with intrinsic sympathomimetic activity (pindolol, acebutolol)

Question 22

other compounds which associate an alpha and beta blocker effect (carvedilol) have been shown equivalent to

Answer 22

isosorbide

1) Such drugs are administered in therapy of cardiac angina in most of the cases orally, as once or twice daily preparation
2) They are well tolerated by the patients in most of the cases

Question 23

Side effects of therapy with non- selective beta blockers

Answer 23

1) Depression of myocardial contractility
2) Bradycardia
3) Bronchoconstriction
4) Peripherical vasoconstriction
5) Sexual dysfunction
6) Depression
7) Sleep disturbances + nightmares
8) Decreasing of glucose tolerance in diabetics

Question 24

Nicorandil

Answer 24

1) a vasodilator which reduce cardiac preload and afterload and decrease cardiac effort.
2) Is acting by activation of potassium channels.

Question 25

Trimetazidine

Answer 25

1) is improving cardiac metabolism and

2) block ATP depletion in cardiac cells.

Question 26

Ranolazine

Answer 26

decrease cardiac contractility by influencing of sodium influx.

Question 27

Ivabradine

Answer 27

decrease cardiac frequency by direct inhibition of “funny” ion channels at sinusal node