How to make better use of thrombolytic therapy in acute ischemic stroke

Neuroprotection for stroke: current status and future perspectives

Neuroprotection aims to prevent salvageable neurons from dying. Despite showing efficacy in experimental stroke studies, the concept of neuroprotection has failed in clinical trials. Reasons for the translational difficulties include a lack of methodological agreement between preclinical and clinical studies and the heterogeneity of stroke in humans compared to homogeneous strokes in animal models. Even when the international recommendations for preclinical stroke research, the Stroke Academic Industry Roundtable (STAIR) criteria, were followed, we have still seen limited success in the clinic, examples being NXY-059 and haematopoietic growth factors which fulfilled nearly all the STAIR criteria. However, there are a number of neuroprotective treatments under investigation in clinical trials such as hypothermia and ebselen. Moreover, promising neuroprotective treatments based on a deeper understanding of the complex pathophysiology of ischemic stroke such as inhibitors of NADPH oxidases and PSD-95 are currently evaluated in preclinical studies. Further concepts to improve translation include the investigation of neuroprotectants in multicenter preclinical Phase III-type studies, improved animal models, and close alignment between clinical trial and preclinical methodologies. Future successful translation will require both new concepts for preclinical testing and innovative approaches based on mechanistic insights into the ischemic cascade.

Temperature affects thrombolytic efficacy using rt-PA and eptifibatide, an in vitro study

The potential for hypothermia as a neuroprotectant during stroke has led to its increase in clinical use. At the same time, combination pharmaceutical therapies for ischemic stroke using recombinant tissue plasminogen activator (rt-PA), and GP IIb-IIIa inhibitors, such as Eptifibatide (Epf ), are under study. However, there is little data on how the reactions triggered by these agents are impacted by temperature. Here, clot lysis during exposure to the combination of rt-PA and Epf is measured in an in vitro human clot model at hypothermic temperatures. The hypothesis is that lytic efficacy of rt-PA and Epf decreases with decreasing temperature. Whole blood clots from 31 volunteers were exposed to rt-PA (0.5 μg/mL) and Epf (0.63 μg/mL) in human fresh-frozen plasma (rt-PA+Epf ), rt-PA alone in plasma (rt-PA Alone), or to plasma alone (Control), at temperatures from 30°C to 37°C, for 30 minutes. Clot lysis was measured using a microscopic imaging technique; the mean fractional clot loss (FCL) at 30 minutes was used to determine lytic efficacy. Temperature had a significant impact on FCL in clots exposed to rt-PA+Epf, with the FCL being lower at 30°C to 36°C than at 37°C. The FCL remained significantly higher for rt-PA+Epf–treated clots than Controls regardless of temperature, with the exception of measurements made at 30°C when no significant differences in the FCL were observed between groups. The use of hypothermia as a neuroprotectant may negatively impact the therapeutic benefit of thrombolytic agents.

Quality of life of elderly ischaemic stroke patients one year after thrombolytic therapy. A comparison between patients with and without thrombolytic therapy

Background

An observational study to examine whether thrombolytic therapy in stroke patients realizes better quality of life outcomes compared to patients without thrombolytic therapy one year after stroke. We also examined whether daily functioning, mental functioning and activities improved after thrombolytic treatment.

Methods

A total of 88 stroke patients were interviewed at home one year post-stroke. Health-related quality of life (HRQOL) was assessed using the RAND-36, disability with the Barthel Index, depression and anxiety with the Hospital Anxiety and Depression Scale, and a questionnaire about patient way of life was completed. People aged under 60, moving to a nursing home or with a haemorrhage were excluded.

Results

The thrombolysis group (TG) had more severe stroke (higher NIHSS) scores and were younger than the group without thrombolytic therapy (WTG). The primary outcome was HRQOL, which was high and nearly identical in both groups, however the TG had significantly better HRQOL for the ‘mental health’ and ‘vitality’ scales. Patients who stopped or reduced their hobbies because of stroke had a significantly worse HRQOL.

One year after stroke, more patients in the TG were totally or severely ADL dependent (12% TG and 0% WTG, p = 0.022). The level of dependence decreased in the TG (p = 0.042) and worsened in the WTG (p < 0.001) after one year. Being more dependent is related to diminishing daily occupations in both groups. In the TG the level of dependence had less impact on visiting family and friends and going on holiday. The prevalence of anxiety disorder and depression was low compared to other studies and there is no significant difference between the two groups.

Conclusion

No major differences in the primary outcome (HRQOL) could be found between the two groups. In addition, no essential difference could be found in mental functioning and participation. We expected that patients undergoing thrombolytic therapy would have worse quality of life because of the greater initial severity of their stroke. Therefore, thrombolytic therapy seems to be of great importance in achieving better quality of life in ischemic stroke patients who respond to this therapy.

Acute stroke management in patients taking dabigatran

Dabigatran etexilate is emerging as an alternative for vitamin K antagonists, but evidence-based guidelines for management of intracerebral hemorrhage and acute ischemic stroke in patients taking this drug are nonexistent. This review summarizes current knowledge on key pharmacological features and the assessment of dabigatran activity. Pragmatic approaches are provided for individualized decision taking with regard to hemostatic therapy and reperfusion strategies in acute stroke patients.