Appropriately trained interventional radiologists performing endovascular thrombectomy in technically complicated stroke cases achieve similar reperfusion and clinical outcomes to those reported in the published literature. This is the conclusion of Andrew Hines, an interventional radiologist at Northeast Charlotte Radiology, Charlotte, USA, presenting his data at the annual meeting of the Society of Interventional Radiology (SIR; 23–28 March, Austin, USA).
“There is a lot of political pressure right now amongst other subspecialties, and they feel that we are not appropriately positioned to perform stroke thrombectomies, so it is even more important for those of us in this room to make sure that our data is extremely robust,” he said to SIR attendees.
Hines said that, although he believes interventional radiologists are doing a good job at demonstrating their technical ability at performing M1 occlusions, the most common type of large vessel occlusion, they must demonstrate that capability in more technically challenging stoke cases to assuage “critics of interventional radiology”. Tandem occlusions are occlusions of the internal carotid artery in addition to occlusions of some of the inter-cerebral vessels and, according to Hines, there is very little literature focusing on gauging how well interventional radiologists are performing these procedures specifically.
“Interventional radiology is not new to this [stroke cases]”, he informed delegates; “75% of the patients in the MR CLEAN study were performed by interventional radiologists, and that was actually the first of the five landmark trials, so we certainly have been here since the beginning.” The other four “landmark” trials he mentioned are ESCAPE, EXTEND IA, SWIFT PRIME, and REVASCAT.
Comparing published studies looking at tandem occlusions specifically, Hines said that “they all have a low patient sample size, ranging from two patients to about 100”. He also noted that both the technical outcomes and the TICI 2B/3 [Thrombolysis In Cerebral Infarction scale; an evaluation of angiographic intracranial flow] varied widely, both “from 50 to 100%”.
Several of the investigators from the five “landmark” trials have conducted subanalyses of their data to look at tandem occlusions. Showing the SIR audience an ESCAPE trial subanalysis, Hines said “In this series, in their tandem occlusions the TICI 2B/3 was 69% for technical success in revascularisation, and their mRS 0–2 at 90 days was 60%. So this sets the bar, I think, as to what we interventional radiologists should be trying to achieve.”
Turning to his own data, Hines then asked the question “So, how well did we do?”. Going through his results, he explained, “With tandem occlusions, we achieved a TICI 2B/3 of 86%—that is almost as good as our M1 data. Our mRS 0–2 at 90 days was 43%, compared to 48.7% [in his M1 data]. Importantly, our complication rate was only 2.7%, and our mortality rate was 24%.
“If you squeeze this data into the various retrospective series”, he continued, “you can see that we are definitely in the top quartile of all of the published series, especially when you look at the series that have more than 30 patients.”
The key takeaway Hines stressed to the audience was that, when appropriately trained, interventional radiologists are proficient at performing these complicated procedures, and that the clinical outcomes are comparable with published data from other specialties who perform these tandem occlusions as part of stroke care.