IHD drugs Flashcards
Nitroglycerine
Verapamil and diltiazem
SA node depression and AV node conduciton supression and can decrease coronary resistance by vasodilation
Coronary vasodilation effect : Nifedipine > Verapamil > Diltiazem
Isosorbide dinitrate
Sodium nitroprusside
Propanolol/Metoprolol
Cardioselective beta-blockers - long acting metaprolol
Nifedipine
Dihydropyridine that doesn’t affect the SA or AV node but can reduce the coronary resistance by coronary vasodilation
Viagra or Sildenafil
Phosphodiesterase-5 inhibitors
Beta-adrenergic blockers
Decreases cardiac oxygen consumption at rest and during exercise. Negative ionotropic and negative chronotropic effects during exercise. Reduction of SBP during physical activity.
Contraindications for beta-adrenergic
Peripheral vascular insufficiency, Heart failure, bradyarrhythmias, high-degree AV-node block
Calcium channel blockers (CCB)
- Coronary vasodilation, reducing ventricular contractility
- Voltage gated Ca2+ channels (L-type) – Ca2+ enters the vascular smooth muscles, cardiac myocytes, SA node and AV node in response to electrical depolarization
- CCB - suppress coronary vasodilation, suppression of cardiac contractility, suppression of automaticity of SA node
- Suppression of conduction of AV node
- Arteriolar vasodilation
- Suppressess the role of Ca2+ on relieving the inhibition of contractile apparatus that allows the actin and myosin binding
CCB examples
Dihydropyridines- Nifedipine, amlodipine, Non-dihydropyridines- Verapamil and Diltiazem.
* Binds to the receptors of alpha-1 subunit of the Ca2+ channels
* Dihydropyridines - affinity more in the perpheral vasculature - vasodilation that is associated with a baroreflex - mediated increase in sympathetic tone to overcome the negative ionotropic effects
Calcium channel blockers adverse effects
- G.I - nausea, vomiting and constipation ( gastric motility)
- CV - Hypotension, Negative ionotropuc action, Bradycardia and AV block, headache, non-Cardiogenic edema of lower extermities ( due to venous dilation)
- Beta-blockers - Depression of AV conduction verapamil and dlitiazem
- Digoxin - Depression of AV conduction and digoxin toxicity
