Intervention Order Matters to Optimize Outcome for Tandem Occlusion

Damian McNamara

June 07, 2018

GOTHENBURG, Sweden — Mechanical thrombectomy followed by carotid stenting was associated with better outcomes compared with the same interventions in reverse order, according to a retrospective study conducted at four high-volume stroke centers.

Thrombectomy followed by stenting, also known as a retrograde approach, yielded a significantly higher rate of successful perfusion, at 92%, than did an antegrade approach, at 56%.

Approximately 10% to 20% of acute ischemic stroke patients present with a tandem occlusion, requiring both intracranial and extracranial interventions, Volker Maus, MD, from the Department of Diagnostic and Interventional Neuroradiology at the University Medical Center Gottingen in Germany said here at the 4th European Stroke Organisation Conference (ESOC) 2018.

A meta-analysis in 2017 showed that thrombectomy was safe and effective for acute anterior ischemic stroke tandem occlusions, with a successful recanalization rate of up to 81% and favorable outcome of 44%.  

However, "no prospective studies deal exclusively with this topic, and either these patients were excluded [from previous research] or only a small number were included," he said. "There are no standardized recommendations for treatment."

To learn more, Maus and colleagues evaluated 165 patients with tandem occlusion treated between May 2013 and December 2017. Forty-one percent had a retrograde repair and 59% underwent an antegrade procedure. The mean patient age was 65 years and 69% were men. Most occlusions occurred in the M1 segment and were associated with large-artery atherosclerosis. Clinicians placed 187 carotid stents during the study.

Time from groin puncture to reperfusion was longer in the retrograde group, at 123 minutes, than in the antegrade cohort, at 103 minutes. The rate of symptomatic intracranial hemorrhage did not vary between groups at discharge or at 3 months.

The investigators defined a favorable clinical outcome as a Modified Rankin Scale score of 0 to 2 at 90 days after intervention.

A greater proportion of the retrograde strategy group achieved this outcome (44%) compared with the antegrade cohort (30%), a statistically significant difference (P < .05).  

"These results raise several questions," Maus said. One is why the retrograde approach was associated with a better outcome. "That is fairly easy to answer — it's because the rate of successful reperfusion is higher in this cohort."

But why the reperfusion rate was higher in the retrograde approach "is not as easy to answer," he said.

There are several possible explanations. For example, in some patients effective combined stent retriever techniques are not feasible with the antegrade approach, or there could be some difficulty or entanglement getting the clot retriever through the carotid stent, he suggested. In addition, increased intracranial flow after carotid stenting could result in clot fragmentation, which in turn could result in poorer reperfusion.

The retrospective nature of the study, use of different antiplatelet agents among the participating centers, and lack of adjustment for variations in thrombectomy technique were potential limitations.

"Despite these limitations, we carefully conclude that thrombectomy of cerebral large-vessel occlusion prior to stenting is a predictive factor of favorable outcome," he said.

Findings "Intriguing"

Asked to comment on the findings, Xabier Urra, MD, PhD, a vascular neurologist at the Functional Unit of Cerebrovascular Diseases, Hospital Clinic, Barcelona, Spain, and co-moderator of the session where these findings were presented, called the results "quite intriguing."   

"My only concern is their rate of reperfusion in the more antegrade approach was pretty low, which could explain their main outcome," Urra told Medscape Medical News. "I don't know if that was due to chance."

The current findings add to a literature without consensus, he said.

"We heard years ago that the right thing with thrombectomy is to first address the intracranial occlusion, because it's the one responsible for most of the damage," he said. "But then everything changed when Dr [Jan] Hoving described that it makes sense to open the carotid artery so there is room for larger catheters, and it also improves the flow."

"There are studies by him showing better intracranial flow is associated with better rates of recanalization. So that made sense, and most of the interventionalists I know start by fixing the carotid — not always with a stent, sometimes with angioplasty."

Maus and Urra have disclosed no relevant financial relationships.

4th European Stroke Organisation Conference (ESOC) 2018. Presented May 17, 2018.

Follow Damian McNamara on Twitter: @MedReporter. For more Medscape Neurology news, join us on Facebook and Twitter.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.