Anti anginal drugs

1. ANTI- ANGINAL DRUGS

Prashiddha Dhakal
MBBS (KUSMS, 11
th
)

2. What Is Angina?
Central chest discomfort or pain due to
transient ishemia of the myocardium
Pain may radiate to one arm OR to both arms
OR to neck OR to jaw OR to the epigastrium
Duration- Less than 20min

3. Types Of Angina
Classical/Typical/Stable/Exertional Angina
•Due to fixed and stable plaque
Prinzmetal/Variant Angina
•Due to spasm of coronary artery
Unstable Angina
•Due to unstable plaque (± thrombus)

4. Pharmacological Goals &
Drugs Classification
↓ Preload (Venodilation)
• Nitrates, Potassium Channel Openers
↓ Afterload (Arteriolodilation)
• Calcium Channel Blockers, Potassium
Channel Openers
↓ Heart Rate
• Beta Blockers, Calcium Channel Blockers
Dilate Coronary Artery
•Dipyridamole

5. NITRATES
Nitroglycerine, Isosorbide Dinitrate, Isosorbide Mononitrate
Release Nitric Oxide in smooth muscles of Veins(mainly) & Arterioles
Stimulate Guanylyl Cyclase & ↑cGMP
Stimulate Protein Kinase G
Dephosphorylation & inactivation of MLCK
Relaxation of vascular smooth muscle

6. NITRATES
Venodilation → ↓ Venous Return → ↓Preload
Venodilation → ↓intraventricular pressure →
less compression on vessels supplying
subendocardial myocardium → ↑ Perfusion
Arteriolodilation → ↓ TPR → ↓ Afterload
Dilates collateral pathways & provides blood
to ischemic area

7. NITRATES

8. BETA BLOCKERS
Non-selective - Propanolol
Cardioselective (β1) - Atenolol, Metoprolol
Have following actions :
-ve Chronotropy (SA Node)
-ve Dromotropy (AV Node)
-ve Inotropy (Contractile myocardium)
-ve Clinotropy (Velocity of contraction &
relaxation)

9. BETA BLOCKERS
Adverse Effects
Fatigue (Blockade of β2 receptors in blood
vessels supplying skeletal muscles)
Bradycardia (Blockade of β1 receptors in
heart)
Precaution
Abrupt withdrawal can ↑heart rate,
↑contractility & cause arrythmia & even MI.
(Upregulation of receptors)

10. BETA BLOCKERS
Contraindications
Prinzmetal Angina
COPD, Asthma,Bronchiectesias (β2 in lungs)
Diabetes Mellitus(β2 in liver & pancreas)
Raynaud’s Disease(β2 in peripheral blood
vessels)
Bradyarrythmias (β1 in heart)
Depression

11. CALCIUM CHANNEL BLOCKERS
Phenyl Alkylamines- Verapamil
Benzothiazepines- Diltiazem
Dihydropyridines- Nifedipine, Amlodipine,
Felodipine
Blocks voltage gated L-type Ca channels
present in cardiac & vascular smooth
muscles

12. CALCIUM CHANNEL BLOCKERS
Depending upon their types, they can have
following actions :
-ve Chronotropy (SA Node)
-ve Dromotropy (AV Node)
-ve Inotropy (Contractile myocardium)
-ve Clinotropy (Velocity of contraction &
relaxation)
↓Afterload (Arteriolodilatation)

13. CALCIUM CHANNEL BLOCKERS
HEART ARTERIOLES
Verapamil ++++ +
Diltiazem ++ ++
Dihydropyridines - ++++
Adverse Effects
•Verapamil- similar to Beta Blockers
•Dihydropyridines- similar to Nitrates
•Diltiazem- common to above two

14. POTASSIUM CHANNEL
OPENERS
Nicorandil, Pinacidil
Opens Potassium channels in vascular
smooth muscles & causes K efflux resulting
into the hyperpolarization of the cell.
Venodilation- ↓Preload
Arteriolodilation- ↓Afterload

15. PHARMACOTHERAPY FOR
ANGINA
Stable Angina
Acute attack- NTG 0.5mg S/L
Prophylaxis-
Nitrates- Isosorbide Mononitrate, Transdermal
NTG
β Blockers- Propanolol, Atenolol, Metoprolol
CCB-Amlodipine, Verapamil SR & Diltiazem SR

16. PHARMACOTHERAPY FOR
ANGINA
Variant Angina
Acute- NTG S/L or I/V
Prophylaxis-
Nitrates- Isosorbide Mononitrate
CCB-Amlodipine, Diltiazem SR
Potassium Channel Openers- Nicorandil,
Pinacidil
β BLOCKERS ARE CONTRAINDICATED

17. PHARMACOTHERAPY FOR
ANGINA
 Unstable Angina
NTG S/L
Antiplatelets agent- Aspirin, Clopidogrel
β Blockers- Atenolol, Metoprolol
CCB- Amlodipine or Nifedipine SR
LMW Heparin