Illustrate the overview of the different classes of anti-anginal drugs and discuss their specific mechanisms of action and indications for use?

Classification of Antianginal Drugs

MODE of ACTION 

  • Organic Nitrates: (Increasing O2 Supply) 

        MOA (Vein) 
        

  • Calcium Channel Blockers: (Increasing O2 supply & Decreasing O2 Demand) 

        MOA - CLICK HERE
      
  1. In case of the smooth muscles of coronary artery, the CCBs prevents the contraction of arterial smooth muscle leading to Arterial Dilation. → Increased O2 Supply 
  2. In Case of Cardiac smooth muscle, CCBs prevents the contraction (inhibiting the formation of MLCK+ ) results in Negative inotropic effect (Decreased Force of Contraction) in Heart.

  • Potassium Channel Opener: (Increased O2 Supply) 

        MOA - 
        


  • Beta Blockers: (Decreasing O2 Demand) 

        MOA - Block the adrenergic beta (BETA 2) receptor of the heart leading to Decreased sympathetic outflow leading to Decreased HR (Negative Inotropic) and Decreased FOC (Negative Chronotropic) & Decreased Conduction of AV node (Decreased Dromotropic) Effects.

Examples & Indications 

Drug class

Indication

Example

Nitrates (Short Acting)

Acute attacks of angina

 

Sublingual nitroglycerin

Nitrates (Long Acting)

Prevention of angina attacks

Management of Stable Angina

Chronic Heart Failure

Isosorbide dinitrate (Oral), isosorbide mononitrate (ORAL)

Beta-blockers

Prevention of angina attacks

High BP

Arrhythmias

Heart Failure  

 

Metoprolol, propranolol

Calcium channel blockers

Acute attacks of angina

Hypertension

Spastic Cerebral Vasospasm  

Nifedipine, verapamil, Amlodipine

Potassium channel Opener

Stable Angina

Severe Hypertension

Rayund’s Syndrome

Nicorandil

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