At the 20th Annual Meeting of the Swiss Cerebrovascular Society SHG, Prof. Jan Gralla, MD, from Inselspital Bern, Switzerland, spoke on “New Approaches in the Intra-arterial Treatment of Acute Stroke.” He presented recent studies on the efficacy of different therapies and indicated which questions need to be addressed next.
What is currently the most efficient therapy in the treatment of endovascular stroke?
Until 2014, the study situation was very confusing. Then, several randomized trials were published showing that patients who receive only systemic thrombolysis fare worse than patients who receive systemic thrombolysis and then thrombectomy. The gold standard today is therefore IV thrombolysis, if possible, but followed by mechanical removal of the thrombus. [1]
Which stroke patterns benefit most from this treatment?
It is now known that patients with large vessel occlusions involving the anterior and middle great cerebral artery should be brought urgently after systemic thrombolysis or at the same time as endovascular intervention. This was the result of a meta-analysis with patient data from five randomized studen. [2]
What technique is used for thrombectomy?
There is a new technique that can be used to remove thrombi very safely and with a very high probability. These are the stent retrievers that have been used very successfully for large vessel occlusions, so in principle all patients should receive immediate endovascular treatment. Stent retrievers in combination with IV thrombolysis are, as I said, the gold standard today.
What about IV thrombolysis, are there any new approaches here?
Attempts have been made to deliver a drug locally into the thrombus rather than through the system. This interarterial thrombolysis is possible but not particularly efficient. Distal thrombectomy also proved ineffective. Another approach is thrombus aspiration; here the books are not yet closed. There are studies on this, although the first showed no advantage over thrombolysis. But now, two new studies are underway to re-examine the thrombus aspiration approach. In the next two years, we will know whether this technology may also be efficient. [3]
What other advantages do you see in the combination of stent retriever and IV thrombolysis?
Patients have a shorter inpatient stay and they are less disabled afterwards. In addition to the medical aspect and the fate of the patient, this therapy is also very cost-effective. You save several thousand francs per patient because long-term care costs are reduced. When you reopen a patient, it costs more money on the day of the procedure, but they are less disabled and require less care in the years to come. This was explored in 2016, in a very nice study published in the Journal of Medical Economics. [4]
The time window is a crucial aspect for the success of the treatment. What are the options for combined therapy?
The time window is currently up to eight hours. We assume that we can still safely treat patients then, but we don’t know for sure. This is an open question. What about patients who are beyond eight hours? Is it still allowed to use the technique here? And what about patients where you don’t know the time window because the stroke occurred while they were sleeping? Further studies are needed here.
Can you give an outlook on further developments in the treatment of acute stroke?
The question at hand is whether systemic thrombolysis is needed at all for the large vessel occlusions. Previously, IV thrombolysis alone was compared with IV thrombolysis with endovascular intervention. Currently, several studies have been published that have investigated the efficacy of direct mechanical intervention versus the current gold standard [5,6,7,8]. In April 2017, another study will start on this, called SWIFT Direct. It will be launched internationally from Bern and conducted in Europe and Canada.
Professor Gralla, thank you very much for this interview.
Interview: Karin Diodà
Literature:
- Campell, et al: Lancet Neurol 2015.
- Goyal M, et al: Lancet 2016; 387: 1723-31.
- Mocco J, et al: Aspiration thrombectomy after intravenous alteplase versus intravenous alteplase alone, Stroke 2017.
- Lobotesis K, et al: Cost-effectiveness of stent-retriever thrombectomy in combination with IV t-PA compared with IV t-PA alone for acute ischemic stroke in the UK, Journ of Medical Economics 2016; 8: 785-794.
- Broeg-Morvay A, et al: Direct mechanical intervention versus combinend intravenous and mechanical intervention in large artery anterior cirulation stroke, Stroke 2016.
- Coutino JC, et al: Combined intravenous thrombolysis and thrombectomy vs thrombectomy alone for acute ischemic stroke, a pooled analysis of the SWIFT and STAR studies.
- Abilleira S, et al: Outcomes after direct thrombectomy or combined intravenous and endovascular treatment are not different, Stroke 2017.
- Rai AT, et al: Intravenous thrombolysis before endovascular therapy for large vessel strokes can lead to significantly higher hospital costs without improving outcomes. NeuroIntervent Surg 2017.
InFo NEUROLOGY & PSYCHIATRY 2017; 15(2): 29-31.
