Transient ischemic attack dipyridamole

Coronary artery disease Due to the vasodilatory effect of dipyridamole, use with caution in patients with severe coronary artery disease (eg, unstable angina, recently sustained Ml). Chest pain may be aggravated in patients with underlying coronary artery disease who are receiving dipyridamole. For stroke or transient ischemic attack patients for whom aspirin is indicated to prevent recurrent Ml or angina pectoris, the aspirin in this product may not provide adequate treatment for the cardiac indications. 

The antiplatelet/antithrombotic activity of dipyridamole has been demonstrated in laboratory and in animal models, and has been shown to inhibit platelet aggregation and vessel-wall thrombogenesis [9-11]. Dipyridamole has been given either alone or with aspirin in the management of myocardial infarction and stroke. For the secondary prevention of stroke or transient ischemic attack, the drug may be given as a modified-release preparation in a dose of 200 mg twice daily. Dipyridamole administered intravenously results in a marked coronary vasodilation and is used in stress testing in patients with ischemic heart disease [5]. 

Dipyridamole in combination with aspirin was more effective in preventing secondary stroke than low-dose aspirin or dipyridamole alone in only one of several studies (15). There is some evidence that dipyridamole can sometimes cause transient ischemic attacks (16). 

A 74-year-old woman had a 3-year history of mild dysarthria, dizziness, and gait ataxia, accompanied by two transient ischemic attacks with involuntary ballistic movements of her left arm lasting several seconds each, and another transient ischemic attack with a right homonymous hemianopia lasting 30 minutes. About 45 minutes after her first-ever oral administration of dipyridamole plus aspirin she developed a transient cerebellar deficit that reproduced features of previous vertebrobasilar ischemic events, as well as severe headache, flushing, and diarrhea. 

The acute onset, the pattern of the cerebellar deficit, and the absence of features of epilepsy suggested that the episode was a transient ischemic attack. Aspirin is not known to cause transient ischemic attacks, and only rarely causes headache, flushing, and diarrhea. Since headache, flushing, and diarrhea, which can be caused by dipyridamole, occurred at the same time as the transient ischemic attacks and did not recur after withdrawal, dipjridamole may have caused the transient ischemic attacks. However, it was not clear whether the attacks occurred despite treatment rather than because of it. 

Siegel AM, Sandor P, Kollias SS, Baumgartner RW. Transient ischemic attacks after dipyridamole-aspirin therapy. J Neurol 2000 247(10) 807-8. 

Dipyridamole (persantine) is a vasodilator that, in combination with warfarin, inhibits embolization from prosthetic heart valves. A single study suggests that dipyridamole plus aspirin reduces strokes in patients with prior strokes or transient ischemic attack. A formulation containing 200 mg of dipyridamole, in an extended-release form, and 25 mg of aspirin (aggrenox) is available. 

The incidence of major adverse reactions to dipyridamole was determined in a multicenter retrospective study, involving 73 806 patients who underwent intravenous dipjridamole stress imaging in 59 hospitals and 19 countries (4). The main conclusion was that the risk of serious dipjridamole-induced adverse effects is very low, a conclusion that is in line with other reports (5), and comparable to that reported for exercise testing in a similar patient population. Combined major adverse events among the entire patient population included 7 cardiac deaths (0.95 per 10000), 13 non-fatal myocardial infarctions (1.76 per 10000), 6 non-fatal sustained ventricular dysrhythmias (0.81 per 10000) (ventricular tachycardia in 2 and ventricular fibrillation in 4), 9 transient cerebral ischemic attacks (1.22 per 10000), 1 stroke, and 9 severe cases of bronch-ospasm (1.22 per 10000). Minor non-cardiac adverse effects were less frequent among the elderly and more frequent in women and patients taking maintenance aspirin. 

---