Dipyridamole

Dipyridamole (trademarked as Persantine and others) is a nucleoside transport inhibitor and a PDE3 inhibitor medication that inhibits blood clot formation^{[3][dead link]} when given chronically and causes blood vessel dilation when given at high doses over a short time.

Medical uses

• Dipyridamole is used to dilate blood vessels in people with
  peripheral arterial disease and coronary artery disease.^[4]
• Dipyridamole has been shown to lower pulmonary hypertension without significant drop of systemic blood pressure.
• It inhibits formation of pro-inflammatory cytokines (
  MMP-9) in vitro and results in reduction of hsCRP^{[clarification needed}
  ] in patients.
• It inhibits proliferation of smooth muscle cells in vivo and modestly increases unassisted patency of synthetic arteriovenous hemodialysis grafts.[5]
• It increases the release of
  tissue plasminogen activator
  from brain microvascular endothelial cells.
• It results in an increase of
  12-hydroxyeicosatetraenoic acid
  in the subendothelial matrix and reduced thrombogenicity of the subendothelial matrix.
• Pretreatment it reduced reperfusion injury in volunteers.
• It has been shown to increase myocardial perfusion and left ventricular function in patients with ischemic cardiomyopathy.
• It results in a reduction of the number of thrombin and PECAM-1 receptors on platelets in stroke patients.
• Cyclic adenosine monophosphate impairs platelet aggregation and also causes arteriolar smooth muscle relaxation. Chronic therapy did not show significant drop of systemic blood pressure.
• It inhibits the replication of mengovirus RNA.^[6]
• It can be used for myocardial stress testing as an alternative to exercise-induced stress methods such as treadmills.

Stroke

A combination of dipyridamole and

A triple therapy of aspirin, clopidogrel, and dipyridamole has been investigated, but this combination led to an increase in adverse bleeding events.^[12]

• Vasodilation occurs in healthy arteries, whereas
  electrocardiogram and echocardiography
  when it causes ischemia.
• Flow heterogeneity (a necessary precursor to ischemia) can be detected with
  Sestamibi
  . However, relative differences in perfusion do not necessarily imply any absolute decrease in blood supply in the tissue supplied by a stenosed artery.

Dipyridamole also has non-medicinal uses in a laboratory context, such as the inhibition of cardiovirus growth in cell culture. ^{[citation needed]}

Drug interactions

Due to its action as a phosphodiesterase inhibitor, dipyridamole is likely to potentiate the effects of

According to Association of Anaesthetists of Great Britain and Ireland 2016 guidelines, dipyridamole is considered to not cause risk of bleeding when receiving neuroaxial anaesthesia and deep nerve blocks. It does not therefore require cessation prior to anaesthesia with these techniques, and can continue to be taken with nerve block catheters in place.^[14]

Overdose

Dipyridamole

• Dipyridamole inhibits the
  platelet aggregation, response^[4] to ADP) and/or cGMP
  .
• Dipyridamole inhibits the cellular reuptake of
  endothelial cells
  , leading to increased extracellular concentrations of adenosine.