A study, published in the Journal of NeuroInterventional Surgery and conducted by Brijesh P Mehta, Division of Neurointerventional Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, USA, and colleagues, has assessed the variability in neurointerventional practice for intra-arterial therapy with tPA for patients with major acute ischaemic stroke secondary to large vessel occlusions.
The authors aimed, using an internet-based survey, to focus on key areas of intra-arterial therapy (practice demographics, operator background, operational protocols, quality and safety assessments, and decision-making and treatment strategies) in order to “gain a better understanding of real-world practice patterns for intra-arterial therapy.”
The majority of the surveyed specialists belonged to a neurointerventional society (Society of Vascular and Interventional Neurology, Society of Neurointerventional Surgery and World Federation of Neurological Societies) and, according to Mehta et al, 140 responses (71 neurologists, 53 radiologists, 14 neurosurgeons and two dual training) were received and analysed (response rate 47.5%).
Most survey participants were in North America (76%) and the remaining participants were in Europe (9.3%), Australia or New Zealand (6.4%), South East Asia (6.4%), South America (1.4%) and Africa (0.7%), of which 71% were based at an academic centre.
Despite studies demonstrating the benefit of shorter time to vessel opening, it was reported that 71% (n=99) of operational protocols had not established a goal time from patient presentation to procedure initiation. Of those with an established goal (n=40), a time interval of 30–60 minutes from the emergency department to intra-arterial therapy was the most commonly used.
According to the authors, there have been recent reports suggesting that conscious sedation is associated with improved outcomes after intra-arterial therapy. However, many physicians prefer general anaesthesia due to the lack of patient movement, which is thought to minimise procedure related complications. Mehta et al reported an even distribution between conscious sedation (51%) and general anaesthesia (49%) reflecting the uncertainty in the field.
In terms of quality and safety the authors reported that high-volume centres more often tracked the interval times to intra-arterial therapy, and participation in clinical trials occurred more often in academic centres.
The survey highlighted a significant variability in decision-making. According to most participants (74%), the decision to initiate therapy was jointly made between the neurointerventionalists and stroke teams with less than eight hours (from symptom onset) as the most common time window for intra-arterial therapy in the anterior circulation, and 24 hours in the posterior circulation. There was a strong emphasis on using imaging findings for treatment selection but with strong variability in imaging technologies and a notable lack of specific imaging criteria.
Fifty five per cent only used CT-based approaches, and MRI was used by 40% (alone or in conjunction with other imaging modalities).
Bridging therapy was performed by 89% with a standard time interval for assessing the patient’s response to intravenous tPA before continuing with intra-arterial therapy used by 55%. In North America, the Penumbra mechanical thrombectomy system was the first-line treatment, and for other countries, retrievable stents were the primary treatment both for medium and large vessel occlusions. This may have been because the US Food and Drug Administration (FDA) had not approved the use of retrievable stents in North America at the time of the survey.
“The strengths of this study include its 48% response rate and inclusion of all neurointerventional specialties,” said Mehta. “The survey provides a comprehensive overview of real-world practice patterns for intra-arterial therapy in acute stroke.”
“Prospective clinical studies are needed to compare effectiveness of these variable approaches in order to develop evidence-based guidelines,” Mehta et al concluded.