Low-dose acetylsalicylic acid (ASA) plus dipyridamole versus dipyridamole alone in the prevention of stroke in patients with reversible ischemic attacks

Antithrombotic Therapy for Primary and Secondary Prevention of Ischemic Stroke: JACC State-of-the-Art Review

Stroke is a devastating condition with significant morbidity and mortality worldwide. Antithrombotic therapy plays a crucial role in both primary and secondary prevention of stroke events. Single or dual antiplatelet therapy is generally preferred in cases of large-artery atherosclerosis and small-vessel disease, whereas anticoagulation is recommended in conditions of blood stasis or hypercoagulable states that mostly result in red thrombi. However, the benefit of antithrombotic therapies must be weighed against the increased risk of bleeding, which can pose significant challenges in the pharmacological management of this condition. This review provides a comprehensive summary of the currently available evidence on antithrombotic therapy for ischemic stroke and outlines an updated therapeutic algorithm to support physicians in tailoring the strategy to the individual patient and the underlying mechanism of stroke.

Efficacy and Safety of Using Dual Versus Monotherapy Antiplatelet Agents in Secondary Stroke Prevention: Systematic Review and Meta-Analysis of Randomized Controlled Clinical Trials

BACKGROUND

Dual antiplatelet treatment (DAPT) with aspirin plus clopidogrel for a limited time is recommended after minor noncardioembolic stroke.

METHODS

We performed a meta-analysis of all major studies that compared the efficacy and safety of DAPT versus monotherapy for the secondary prevention of recurrent stroke or transient ischemic attack. The primary outcomes were stroke and the composite of stroke, transient ischemic attack, acute coronary syndrome, and death from any cause. The safety outcome was major hemorrhage. Relative risk (RR) and 95% CIs were calculated. Heterogeneity was assessed by I² and Cochrane Q statistics.

RESULTS

The analysis included 27 358 patients, the quality of evidence was moderate to low, and the heterogeneity for all the comparisons was low (I²≤25%). Compared with monotherapy, DAPT reduced the risk of recurrent stroke (RR, 0.71 [95% CI, 0.63-0.81]) and composite outcome (RR, 0.76 [95% CI, 0.69-0.83]) but increased the risk of major bleeding (RR, 2.17 [95% CI, 1.45-3.25]). In the subgroup analysis, ≤30 days of DAPT increased the risk of hemorrhage relative to monotherapy (RR, 1.94 [95% CI, 1.08-3.52]). In the sensitivity analysis, the risk for hemorrhage with ≤30 days of DAPT after excluding the combination of aspirin plus ticagrelor was comparable to monotherapy (RR, 1.42 [95% CI, 0.77-2.60]). However, the risk for stroke recurrence and composite outcomes in the subgroup and sensitivity analyses remain decreased compared with monotherapy.

CONCLUSIONS

DAPT decreases the risk of recurrent stroke and composite events compared with monotherapy. DAPT increases the risk of major hemorrhage, except if the treatment is limited to 30 days and does not include the combination of aspirin plus ticagrelor.

Short- vs. long-term dual antiplatelet therapy in secondary prevention for ischaemic stroke: a network metanalysis

AIMS

This review aimed to compare the efficacy and safety of short-term (≤3 months) and long-term (≥1 year) dual-antiplatelet therapy (DAPT) in secondary prevention for ischaemic stroke.

METHODS AND RESULTS

We searched MEDLINE, EMBASE (Ovid), PubMed, Cochrane Library, ClinicalTrials.gov, and Google Advanced Search for randomized controlled trials. The population consisted of patients with recent ischaemic stroke or transient ischaemic attack. The intervention was DAPT with a combination of aspirin, clopidogrel, and dipyridamole compared to either aspirin or clopidogrel in monotherapy. The primary outcome was the rate of all recurrent stroke (ischaemic and haemorrhagic). Secondary outcomes were ischaemic stroke, all bleeding, severe bleeding, all-cause death, cardiovascular death, and myocardial infarction. Data were pooled by network metanalysis and pairwise metanalyses. Sixteen studies with 55 261 participants were included. Compared to aspirin, DAPT with aspirin clopidogrel decreased the risk of recurrent stroke [short-term odds ratio (OR) 0.67, 95% confidence interval (CI) 0.58-0.77; long-term OR 0.84, 95% CI 0.70-1.01] at the expense of increased risk of bleeding (short-term OR 1.76, 95% CI 1.26-2.46; long-term OR 2.25, 95% CI 1.97-2.57). Dual antiplatelet therapy with aspirin clopidogrel and clopidogrel in monotherapy had similar long-term risk of recurrent stroke (OR 0.98, 95% CI 0.83-1.14), but DAPT was associated with increased risk of bleeding (OR 2.77, 95% CI 2.21-3.46). Network metanalysis showed that short-term aspirin clopidogrel DAPT had the best risk-benefit profile, followed by long-term aspirin clopidogrel DAPT and clopidogrel alone. Aspirin dipyridamole DAPT was less effective.

CONCLUSION

Short-term DAPT had better risk-benefit profile than long-term DAPT.

Triple versus guideline antiplatelet therapy to prevent recurrence after acute ischaemic stroke or transient ischaemic attack: the TARDIS RCT

BACKGROUND

Two antiplatelet agents are better than one for preventing recurrent stroke after acute ischaemic stroke or transient ischaemic attack (TIA). Therefore, intensive treatment with three agents might be better still, providing it does not cause undue bleeding.

OBJECTIVE

To compare the safety and efficacy of intensive therapy with guideline antiplatelet therapy for acute ischaemic stroke and TIA.

DESIGN

International prospective randomised open-label blinded end-point parallel-group superiority clinical trial.

SETTING

Acute hospitals at 106 sites in four countries.

PARTICIPANTS

Patients > 50 years of age with acute non-cardioembolic ischaemic stroke or TIA within 48 hours of ictus (stroke).

INTERVENTIONS

Participants were allocated at random by computer to 1 month of intensive (combined aspirin, clopidogrel and dipyridamole) or guideline (combined aspirin and dipyridamole, or clopidogrel alone) antiplatelet agents, and followed for 90 days.

MAIN OUTCOME MEASURES

The primary outcome was the incidence and severity of any recurrent stroke (ischaemic, haemorrhagic; assessed using the modified Rankin Scale) or TIA within 90 days by blinded telephone follow-up. Analysis using ordinal logistic regression was by intention to treat. Other outcomes included bleeding and its severity, death, myocardial infarction (MI), disability, mood, cognition and quality of life.

RESULTS

The trial was stopped early on the recommendation of the Data Monitoring Committee after recruitment of 3096 participants (intensive, n = 1556; guideline, n = 1540) from 106 hospitals in four countries between April 2009 and March 2016. The incidence and severity of recurrent stroke or TIA did not differ between intensive and guideline therapy in 3070 (99.2%) participants with data [93 vs. 105 stroke/TIA events; adjusted common odds ratio 0.90, 95% confidence interval (CI) 0.67 to 1.20; p = 0.47]. Major (encompassing fatal) bleeding was increased with intensive as compared with guideline therapy [39 vs. 17 participants; adjusted hazard ratio (aHR) 2.23, 95% CI 1.25 to 3.96; p = 0.006]. There were no differences between the treatment groups in all-cause mortality, or the composite of death, stroke, MI and major bleeding (aHR 1.02, 95% CI 0.77 to 1.35; p = 0.88).

LIMITATIONS

Patients and investigators were not blinded to treatment. The comparator group comprised two guideline strategies because of changes in national guidelines during the trial. The trial was stopped early, thereby reducing its statistical power.

CONCLUSIONS

The use of three antiplatelet agents is associated with increased bleeding without any significant reduction in recurrence of stroke or TIA.

FUTURE WORK

The safety and efficacy of dual antiplatelet therapy (combined aspirin and clopidogrel) versus aspirin remains to be defined. Further research is required on identifying individual patient response to antiplatelets, and the relationship between response and the subsequent risks of vascular recurrent events and bleeding complications.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN47823388.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 48. See the NIHR Journal Library website for further project information. The Triple Antiplatelets for Reducing Dependency after Ischaemic Stroke (TARDIS) vanguard phase was funded by the British Heart Foundation (grant PG/08/083/25779, from 1 April 2009 to 30 September 2012) and indirect funding was provided by the Stroke Association through its funding of the Stroke Trials Unit, Division of Clinical Neuroscience, University of Nottingham, Nottingham, UK. There was no commercial support for the trial and antiplatelet drugs were sourced locally at each site. The trial was sponsored by the University of Nottingham.

Dual versus mono antiplatelet therapy for acute non-cardioembolic ischaemic stroke or transient ischaemic attack: a systematic review and meta-analysis

Objective

Recent years have seen new evidence on the efficacy and safety of dual antiplatelet therapy for secondary stroke prevention. We updated a meta-analysis of randomised controlled trials evaluating dual antiplatelet versus monotherapy for patients with acute non-cardioembolic ischaemic stroke (IS) or transient ischaemic attack (TIA).

Methods

We searched PubMed and identified randomised controlled trials evaluating dual antiplatelet versus monotherapy for acute non-cardioembolic IS or TIA within 3 days of ictus up to May 2018. Risk ratio (RR) with 95% CI were calculated using random effects models. Clinical endpoints included stroke recurrence, composite vascular events and major bleeding.

Results

18 randomised controlled trials including 15 515 patients were pooled in the meta-analysis. When compared with monotherapy among patients with acute IS or TIA, dual antiplatelet therapy reduced the risk of stroke recurrence (RR 0.69; 95% CI 0.61 to 0.78; p<0.001) and composite vascular events (RR 0.72; 95% CI 0.64 to 0.80; p<0.001). Dual therapy was associated with a significant increase in the risk of major bleeding (RR 1.77; 95% CI 1.09 to 2.87; p=0.02) when all trial data were combined. However, when all previous trials before the completion of the POINT trial were analysed, dual antiplatelet versus monotherapy was not associated with a significant increase in the risk of major bleeding (RR 1.46; 95% CI 0.77 to 2.75; p=0.25).

Conclusions

Among patients with acute non-cardioembolic IS or TIA within 3 days of ictus, dual antiplatelet therapy was associated with a reduction in stroke recurrence, and composite vascular events, when compared with monotherapy. However, a significant increase in the risk of major bleeding was observed.

Long-Term Antiplatelet Mono- and Dual Therapies After Ischemic Stroke or Transient Ischemic Attack: Network Meta-Analysis

BACKGROUND

The latest guidelines do not make clear recommendations on the selection of antiplatelet therapies for long-term secondary prevention of stroke. We aimed to integrate the available evidence to create hierarchies of the comparative efficacy and safety of long-term antiplatelet therapies after ischemic stroke or transient ischemic attack.

METHODS AND RESULTS

We performed a network meta-analysis of randomized controlled trials to compare 11 antiplatelet therapies in patients with ischemic stroke or transient ischemic attack. In December 2014, we searched Medline, Embase, and the Cochrane Library database for trials. The search identified 24 randomized controlled trials including a total of 85 667 patients with antiplatelet treatments for at least 1 year. Cilostazol significantly reduced stroke recurrence in comparison with aspirin (odds ratio 0.66, 95% credible interval 0.44 to 0.92) and dipyridamole (odds ratio 0.57, 95% credible interval 0.34 to 0.95), respectively. Cilostazol also significantly reduced intracranial hemorrhage compared with aspirin, clopidogrel, terutroban, ticlopidine, aspirin plus clopidogrel, and aspirin plus dipyridamole. Aspirin plus clopidogrel could not significantly reduce stroke recurrence compared with monotherapies but caused significantly more major bleeding than all monotherapies except terutroban. The pooled estimates did not change materially in the sensitivity analyses of the primary efficacy outcome.

CONCLUSIONS

Long-term monotherapy was a better choice than long-term dual therapy, and cilostazol had the best risk-benefit profile for long-term secondary prevention after stroke or transient ischemic attack. More randomized controlled trials in non-East Asian patients are needed to determine whether long-term use of cilostazol is the best option for the prevention of recurrent stroke.

Early Dual Versus Mono Antiplatelet Therapy for Acute Non-Cardioembolic Ischemic Stroke or Transient Ischemic Attack

Background—

Emerging studies suggest that early administration of dual antiplatelet therapy may be better than monotherapy for prevention of early recurrent stroke and cardiovascular outcomes in acute ischemic stroke and transient ischemic attack (TIA). We performed a meta-analysis of randomized, controlled trials evaluating dual versus mono antiplatelet therapy for acute noncardioembolic ischemic stroke or TIA.

Methods and Results—

We assessed randomized, controlled trials investigating dual versus mono antiplatelet therapy published up to November 2012 and the CHANCE trial (Clopidogrel in High-risk patients with Acute Non-disabling Cerebrovascular Events), for efficacy and safety outcomes in adult patients with acute noncardioembolic ischemic stroke or TIA with treatment initiated within 3 days of ictus. In total, 14 studies of 9012 patients were included in the systematic review and meta-analysis. Dual antiplatelet therapy significantly reduced risk of stroke recurrence (risk ratio, 0.69; 95% confidence interval, 0.60–0.80; P <0.001) and the composite outcome of stroke, TIA, acute coronary syndrome, and all death (risk ratio, 0.71; 95% confidence interval, 0.63–0.81; P <0.001) when compared with monotherapy, and nonsignificantly increased risk of major bleeding (risk ratio, 1.35; 95% confidence interval, 0.70–2.59, P =0.37). Analyses restricted to the CHANCE Trial or the 7 double-blind randomized, controlled trials showed similar results.

Conclusions—

For patients with acute noncardioembolic ischemic stroke or TIA, dual therapy was more effective than monotherapy in reducing risks of early recurrent stroke. The results of the CHANCE study are consistent with previous studies done in other parts of the world.

Combination aspirin and clopidogrel for secondary prevention of ischemic stroke

OPINION STATEMENT

Though antiplatelet agents are the mainstay of antithrombotic therapy for secondary prevention of noncardioembolic cerebral ischemic events, the efficacy of combination aspirin and clopidogrel has yet to be clarified by clinical trials. Current evidence suggests that there is no role for long-term combination of aspirin/clopidogrel for secondary stroke prevention. Recent preliminary data from the CHANCE (Clopidogrel in High-risk Patients with Acute Non-disabling Cerebrovascular Events) trial suggests that stroke recurrence at 90 days is reduced by a short course (21 days) of combination aspirin/clopidogrel initiated within 24 hours of minor stroke or TIA (Transient Ischemic Attack) compared with aspirin alone [1••] (Table 1). Other ongoing trials, which are also investigating the role of short-term combination antiplatelet therapy initiated immediately after minor stroke and TIA, will determine if these findings will be replicated.

Dual or mono antiplatelet therapy for patients with acute ischemic stroke or transient ischemic attack: systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND PURPOSE

Antiplatelets are recommended for patients with acute noncardioembolic stroke or transient ischemic attack. We compared the safety and efficacy of dual versus mono antiplatelet therapy in patients with acute ischemic stroke or transient ischemic attack.

METHODS

Completed randomized controlled trials of dual versus mono antiplatelet therapy in patients with acute (≤3 days) ischemic stroke/transient ischemic attack were identified using electronic bibliographic searches. The primary outcome was recurrent stroke (ischemic, hemorrhagic, unknown; fatal, nonfatal). Comparison of binary outcomes between treatment groups was analyzed with random effect models and described using risk ratios (95% CI).

RESULTS

Twelve completed randomized trials involving 3766 patients were included. In comparison with mono antiplatelet therapy, dual therapy (aspirin+dipyridamole and aspirin+clopidogrel) significantly reduced stroke recurrence, dual 58 (3.3%) versus mono 91 (5.0%; risk ratio, 0.67; 95% CI, 0.49-0.93); composite vascular event (stroke, myocardial infarction, vascular death), dual 74 (4.4%) versus mono 106 (6%; risk ratio, 0.75; 95% CI, 0.56-0.99); and the combination of stroke, transient ischemic attack, acute coronary syndrome, and all death, dual 100 (1.7%) versus mono 136 (9.1%; risk ratio, 0.71; 95% CI, 0.56-0.91); dual therapy was also associated with a nonsignificant trend to increase major bleeding, dual 15 (0.9%) versus mono 6 (0.4%; risk ratio, 2.09; 95% CI, 0.86-5.06).

CONCLUSIONS

Dual antiplatelet therapy appears to be safe and effective in reducing stroke recurrence and combined vascular events in patients with acute ischemic stroke or transient ischemic attack as compared with mono therapy. These results need to be tested in prospective studies.

Dipyridamole for Preventing Recurrent Ischemic Stroke and Other Vascular Events

Background and Purpose— Results from randomized controlled trials of dipyridamole, given with or without aspirin, for secondary prevention after ischemic stroke or transient ischemic attack (TIA) have given conflicting results. We performed a meta-analysis using individual patient data from relevant randomized controlled trials.

Methods— Randomized controlled trials involving dipyridamole in patients with previous ischemic stroke or TIA were sought from searches of the Cochrane Library, other electronic databases, references lists, earlier reviews, and contact with the manufacturer of dipyridamole. Individual patient data were merged from 5 of 7 relevant trials involving 11 459 patients. Results were adjusted for age, gender, qualifying event, and history of previous hypertension.

Results— Recurrent stroke was reduced by dipyridamole as compared with control (OR, 0.82; 95% CI, 0.68 to 1.00), and by combined aspirin and dipyridamole versus aspirin alone (OR, 0.78; 95% CI, 0.65 to 0.93), dipyridamole alone (OR, 0.74; 95% CI, 0.60 to 0.90), or control (OR, 0.61; 95% CI, 0.51 to 0.71). The point estimates obtained for the comparisons of aspirin and dipyridamole versus control (OR, 0.63; significant) or versus aspirin (OR, 0.88; nonsignificant) were similar if the data from the largest trial, ESPS II (which provided 57% of data), were excluded. Similar findings were observed for nonfatal stroke. The combination of aspirin and dipyridamole also significantly reduced the composite outcome of nonfatal stroke, nonfatal myocardial infarction, and vascular death as compared with aspirin alone (OR, 0.84; 95% CI, 0.72 to 0.97), dipyridamole alone (OR, 0.76; 95% CI, 0.64 to 0.90), or control (OR, 0.66; 95% CI, 0.57 to 0.75). Vascular death was not altered in any group.

Conclusions— Dipyridamole, given alone or with aspirin, reduces stroke recurrence in patients with previous ischemic cerebrovascular disease. The combination of aspirin and dipyridamole also reduces the composite of nonfatal stroke, nonfatal myocardial infarction, and vascular death as compared with aspirin alone.

Aggrenox((R)) versus other pharmacotherapy in preventing recurrent stroke

Stroke is the third leading cause of death in the US with recurrent events a high likelihood in those who survive an initial event. The long-term goal of therapy is to prevent the recurrence of stroke and other atherosclerotic events. Aspirin has been the first-line agent for stroke prevention for a long time. As new antiplatelet agents have been introduced, their role in the secondary prevention of stroke remains to be defined. In particular, the role of the combination of aspirin and modified-release dipyridamole (Aggrenox, Boehringer Ingelheim Corp.), the newest product, in the secondary prevention of stroke, remains unknown. The purpose of this manuscript is to review the evidence of these antiplatelet agents in the secondary prevention of stroke and arrive at a conclusion specifically regarding the role of Aggrenox. Clinical studies which examined stroke as a single primary outcome or as one event in a combined primary outcome will be reviewed.

Collaborative overview of randomised trials of antiplatelet therapy--I: Prevention of death, myocardial infarction, and stroke by prolonged antiplatelet therapy in various categories of patients. Antiplatelet Trialists' Collaboration

OBJECTIVE

To determine the effects of "prolonged" antiplatelet therapy (that is, given for one month or more) on "vascular events" (non-fatal myocardial infarctions, non-fatal strokes, or vascular deaths) in various categories of patients.

DESIGN

Overviews of 145 randomised trials of "prolonged" antiplatelet therapy versus control and 29 randomised comparisons between such antiplatelet regimens.

SETTING

Randomised trials that could have been available by March 1990.

SUBJECTS

Trials of antiplatelet therapy versus control included about 70,000 "high risk" patients (that is, with some vascular disease or other condition implying an increased risk of occlusive vascular disease) and 30,000 "low risk" subjects from the general population. Direct comparisons of different antiplatelet regimens involved about 10,000 high risk patients.

RESULTS

In each of four main high risk categories of patients antiplatelet therapy was definitely protective. The percentages of patients suffering a vascular event among those allocated antiplatelet therapy versus appropriately adjusted control percentages (and mean scheduled treatment durations and net absolute benefits) were: (a) among about 20,000 patients with acute myocardial infarction, 10% antiplatelet therapy v 14% control (one month benefit about 40 vascular events avoided per 1000 patients treated (2P < 0.00001)); (b) among about 20,000 patients with a past history of myocardial infarction, 13% antiplatelet therapy v 17% control (two year benefit about 40/1000 (2P < 0.00001)); (c) among about 10,000 patients with a past history of stroke or transient ischaemic attack, 18% antiplatelet therapy v 22% control (three year benefit about 40/1000 (2P < 0.00001)); (d) among about 20,000 patients with some other relevant medical history (unstable angina, stable angina, vascular surgery, angioplasty, atrial fibrillation, valvular disease, peripheral vascular disease, etc), 9% v 14% in 4000 patients with unstable angina (six month benefit about 50/1000 (2P < 0.00001)) and 6% v 8% in 16,000 other high risk patients (one year benefit about 20/1000 (2P < 0.00001)). Reductions in vascular events were about one quarter in each of these four main categories and were separately statistically significant in middle age and old age, in men and women, in hypertensive and normotensive patients, and in diabetic and nondiabetic patients. Taking all high risk patients together showed reductions of about one third in non-fatal myocardial infarction, about one third in non-fatal stroke, and about one third in vascular death (each 2P < 0.00001). There was no evidence that non-vascular deaths were increased, so in each of the four main high risk categories overall mortality was significantly reduced. The most widely tested antiplatelet regimen was "medium dose" (75-325 mg/day) aspirin. Doses throughout this range seemed similarly effective (although in an acute emergency it might be prudent to use an initial dose of 160-325 mg rather than about 75 mg). There was no appreciable evidence that either a higher aspirin dose or any other antiplatelet regimen was more effective than medium dose aspirin in preventing vascular events. The optimal duration of treatment for patients with a past history of myocardial infarction, stroke, or transient ischaemic attack could not be determined directly because most trials lasted only one, two, or three years (average about two years). Nevertheless, there was significant (2P < 0.0001) further benefit between the end of year 1 and the end of year 3, suggesting that longer treatment might well be more effective. Among low risk recipients of "primary prevention" a significant reduction of one third in non-fatal myocardial infarction was, however, accompanied by a non-significant increase in stroke. Furthermore, the absolute reduction in vascular events was much smaller than for high risk patients despite a much longer treatment period (4.4% antiplatelet therapy v 4.8% control; five year

Antithrombotic treatment of cerebrovascular disease

The most common type of cerebrovascular disease is ischaemia or infarction from atherothrombosis or cardiac embolism. Antithrombotic treatment with an antiplatelet agent or anticoagulant assumes a prior clinical classification into categories of transient ischaemic attack (TIA) or minor stroke, acute partial stable stroke, stroke-in-progression, and completed stroke. Aspirin reduces the risk of stroke, myocardial infarction, and death after TIA or minor stroke secondary to atherothrombosis. Aspirin is effective in both sexes at a dose of 300 or 1200 mg/day. Ticlopidine (500 mg/day), a new antiplatelet agent, is more effective than aspirin in preventing stroke and death in patients with TIA or minor stroke. Ticlopidine (500 mg/day) is effective in preventing recurrent stroke, myocardial infarction, or vascular death in patients with completed stroke. Aspirin has not been directly shown to be effective after completed stroke. No clear evidence exists for the use of anticoagulants in atherothrombotic cerebral vascular disease in patients presenting with TIA or minor stroke, acute partial stable stroke, stroke-in-progression, or completed stroke. Anticoagulation for rheumatic valvular heart disease is effective in preventing recurrent embolism. Long-term anticoagulation of patients with mechanical prosthetic valves protects against initial embolism and prevents recurrent embolism. The addition of aspirin (500-1000 mg/day) to warfarin reduces the rate of cerebral embolism from mechanical prosthetic heart valves but is associated with increased bleeding. The addition of dipyridamole (400 mg/day) to warfarin may be more effective than aspirin in reducing the rate of cerebral embolism from mechanical prosthetic heart valves and has fewer bleeding side-effects. Anticoagulation during the hospital phase of myocardial infarction reduces the incidence of systemic embolism/stroke. Long-term anticoagulation of patients after the hospital phase of myocardial infarction reduces the incidence of systemic embolism/stroke, recurrent myocardial infarction and death. Prophylactic anticoagulant treatment of patients with non-valvular atrial fibrillation reduces the incidence of embolism, but the optimal duration of treatment is not known. Immediate anticoagulation of patients with completed cardioembolic stroke is safe and effective in preventing recurrent embolism.

Platelet aggregation in transient global amnesia

We found a correlation between increased platelet aggregation parameters and transient global amnesia and no differences between patients with transient global amnesia and transient ischemic attacks. Our findings support the theory of a vascular mechanism for transient global amnesia.