Dipyridamole (Persantine)

Indications

  • Prevention of Postoperative Thromboembolic Complications of Cardiac Valve Replacement

Pharmacology

  • Platelet Aggregation Inhibitor (see Coagulopathy, [[Coagulopathy]]): inhibition of platelet secretion
    • Mechanisms
      • Inhibition of platelet (and endothelial and RBC) adenosine reuptake -> increase in local adenosine concentration -> adenosine binding to platelet A2-receptor -> stimulation of platelet adenylate cyclase and increased platelet cAMP
      • Phosphodiesterase inhibition (in various tissues): since phosphodiesterase degrades cAMP, this increases cAMP
        • Inhibition of cAMP-PDE is weak
        • More potent inhibition of cGMP-PDE, augmenting the increase in cGMP produced by nitric oxide

Hemodynamic Effects

  • Dose-related decrease in systemic vascular resistance (SVR) -> hypotension
  • Dose-related decrease in coronary vascular resistance -> increased coronary blood flow
  • Acute IV Dipyridamole Administration: may worsen regional myocardial perfusion distal to partial occlusion of coronary arteries -> this provides the rationale for using Persantine in coronary stress testing

Adverse Effects


References

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