Published: Tuesday 30 January 2018
The International Stroke Conference (ISC) is the world's largest meeting dedicated to the science and treatment of stroke and its effects. This year it took place in Los Angeles, USA.
What did we learn?
Members of the ISC Programme Committee got together to discuss what we can learn from this year's conference in terms of the compelling research presented and what this means for the future, including changes in clinical care.
The DEFUSE-3 trial
Thrombectomy is an emergency treatment which can be used for some stroke patients who have a blockage in a large artery in the brain. The procedure involves the surgical removal of the clot causing the blockage using mechanical or suction devices.
The findings from the DEFUSE-3 trial were presented at the ISC and simultaneously published in the New England Journal of Medicine.
DEFUSE-3 investigated whether thrombectomy was effective at improving outcomes, for selected patients, when treated within a six to 16 hour window after stroke. These patients had brain scans which indicated that they were likely to have a sufficient amount of salvageable brain tissue that could be saved by using the procedure.
Of the 182 patients taking part in the trial, 92 received thrombectomy in addition to standard medical care, and 90 received standard medical care alone.
Of the patients who received thrombectomy, almost half had a ‘good functional outcome' at 90 days after their stroke. Of the patients who received standard medical care alone, only one in six had a good outcome within the same timeframe. This result indicates a dramatically positive result of treatment with thrombectomy when started between six and16 hours after stroke.
The findings from DEFUSE-3 informed the latest stroke guidelines from the American Heart Association/American Stroke Association in the USA.
For an overview of the trial findings and their interpretation, watch the video from Greg Albers. MD, Director of the Stanford Stroke Centre.
The EXTEND-IA TNK trial
Thrombolysis is an emergency treatment for eligible stroke patients in which clot-busting drugs are used to dissolve the clot causing the stroke.
At present, there is only one drug licensed for use in thrombolysis called alteplase.
The EXTEND-IA TNK trial compared the use of a new drug for thrombolysis, tenecteplase, against alteplase. This was to see if the new drug was more effective at returning blood flow to a blocked artery, prior to further treatment of the patient with a thrombectomy procedure.
Of the 202 patients taking part in the trial, 101 were randomly assigned to receive thrombolysis with tenecteplase (0.25mg/kg of patient body weight) and then received thrombectomy. The other half of patients received thrombolysis with alteplase (0.9mg/kg) and then went on to receive thrombectomy. In all cases, thrombolysis was delivered within 4.5 hours of stroke.
The study found that tenecteplase was superior to alteplase in being able to return blood flow to the blocked artery, and that there was also a significant improvement in functional outcomes of patients 90 days after their stroke in those who had received tenecteplase relative to those who received alteplase.
Other on-going trials are investigating the effectiveness of tenecteplase versus alteplase in stroke patients who do not go on to receive thrombectomy afterward. One of these is the Stroke Association and BHF co-funded ATTEST-2 study in the UK.
For an overview of the trial findings and their interpretation, watch the video from Bruce C. Campbell MBBS (Hons), PhD, Royal Melbourne Hospital.
International development take homes from ISC18
A number of sessions that I attended were of particular interest to our work supporting SSOs in low and middle-income countries (LMICs).
Professor Amanda Thrift’s session on data gaps in LMICs, resonated with the comments I have heard from many SSOs: that they need better data to plan their stroke support activities. Stroke is often not a priority in many LMICs, where health systems have often been set up in response to communicable diseases and malnutrition.
There are few high quality stroke incidence studies, many studies are outdated and also may not reflect what is happening countrywide. A potential solution to bridge the data gap is the current Lancet Commission on stroke in LMICs. This includes a survey of government and health professionals to identify hospital-based registries, to establish whether health records are used, and to identify other clinical databases. As SSOs know, better estimates of data on stroke give greater leverage with policy makers to reallocate resources to stroke, and longitudinal data enables assessment of the effectiveness of their interventions.
Professor Jeyaraj Pandian’s session underlined the reality of stroke care in LMICs in Asia. The challenges for pre-hospital care are the lack of availability of ambulances and the volume of traffic in many urban settings, which means precious time is wasted.
A challenge in proving stroke unit care is the low number of neurologists in relation to the level of population. Professor Pandian shared examples from India, including the implementation of stroke unit care utilising existing resources and training frontline health workers to identify stroke. In both cases, the interventions showed better outcomes for stroke patients. These innovations are valuable examples for SSOs to use in their advocacy and awareness raising activities.