Stent-retriever thrombectomy, particularly when performed using the Solitaire device, emerged as having the best efficacy and safety profile for the treatment of acute stroke, according to a network meta-analysis published online last month ahead of print in the Journal of NeuroInterventional Surgery.
While endovascular therapy using stent-retrievers has been shown in randomized trials to offer superior outcomes in appropriate patients with large vessel occlusions, “important questions remain regarding the relative efficacy and safety of different devices,” write researchers led by Hamidreza Saber, MD, (Wayne State University School of Medicine, Detroit, MI).” The major trials used stent retrievers for mechanical thrombectomy, no randomized trial has compared them head-to-head.
Saber and colleagues conducted a network meta-analysis to compare mechanical thrombectomy devices—including Trevo (Stryker Neurovascular), Solitaire (Medtronic), Aspiration (Penumbra), Merci (Stryker)—as well as strategies (ie, stent retriever vs aspiration) across trials.
To evaluate devices, they identified six relevant randomized controlled trials: SWIFT, TREVO2, EXTEND-IA, SWIFT-PRIME, REVASCAT, and THERAPY. Together, these trials comprised 871 patients. This included 472 patients in a comparison of Solitaire vs medical therapy alone, 108 in a comparison of Aspiration vs medical therapy alone, 178 in a comparison of Trevo vs Merci, and 113 in a comparison of Solitaire vs Merci.
When medical therapy alone was used as the reference, both the Trevo (OR 4.14, credible interval [CrI] 1.41-11.80) and Solitaire (OR 2.55, CrI 1.75-3.74) devices, but not the Merci (OR 1.67, CrI 0.69–3.79) device, were associated with a significantly greater likelihood of functional independence at 90 days, defined as an mRS 0-2.
In terms of providing best functional outcomes, probability rankings were highest for Solitaire and lowest for medical therapy. With respect to providing the lowest risk of symptomatic intracranial hemorrhage, Solitaire again ranked highest, Trevo dropping to fourth place, after medical therapy.
Device Analysis: Probability Rankings for Efficacy and Safety
|
|
90-Day mRS 0-2 |
Low Rate of Symptomatic Intracranial Hemorrhage |
|
Solitaire |
92% |
76% |
|
Trevo |
72% |
22% |
|
Aspiration |
43% |
73% |
|
Merci |
37% |
9% |
|
Medical Therapy Alone |
0.06% |
68% |
In addition, use of the Aspiration or Solitaire devices was associated with a significantly lower rate of catastrophic outcomes compared with either medical treatment alone or use of the Merci or Trevo devices.
To evaluate strategies, the investigators identified seven relevant trials: MRCLEAN, ESCAPE, EXTEND-IA, SWIFT-PRIME, REVASCAT, THERAPY, ASTER. Together, these comprised 1,737 patients.
Both stent-retriever (OR 2.38, CrI 1.89-2.98) and aspiration (OR 1.92, CrI 1.24-2.86) thrombectomy were associated with a significantly greater likelihood of 90-day functional independence than medical therapy alone.
With respect to both efficacy and safety outcomes, stent-retriever thrombectomy ranked higher than aspiration, and both ranked much higher than medical therapy alone.
Strategy Analysis: Probability Rankings for Efficacy and Safety
|
|
90-Day mRS 0-2 |
Low Rate of Symptomatic Intracranial Hemorrhage |
|
Stent-Retriever Thrombectomy |
95% |
61% |
|
Aspiration |
54% |
47% |
|
Medical Therapy Alone |
0.0008% |
31% |
Both stent-retriever and aspiration thrombectomy were associated with a significantly lower risk of catastrophic outcomes than medical therapy alone.
“Our [network meta-analysis] of available randomized data suggests that the Trevo and Solitaire devices are superior in terms of functional independence whereas the Solitaire and Aspiration devices have lower rates of [symptomatic intracerebral hemorrhage] and catastrophic outcomes,” conclude the authors. “Overall, first-line treatment with a stent retriever device was associated with a higher top rank probability for functional independence than aspiration, whereas both first-line stent retriever and aspiration techniques were equal in safety outcomes.”
Explaining their study methods, the researchers say that this appears to be the first network meta-analysis to take on these questions. “This approach allowed us to synthetize randomize evidence to perform multiple treatment comparisons of devices for which no direct pairwise comparison is available, while completely respecting randomization,” they note.
Source:
Saber H, Rajah GB, Kherallah RY, et al. Comparison of the efficacy and safety of thrombectomy devices in acute stroke: A network meta-analysis of randomized trials. J NeuroInterv Surg. 2017;Epub ahead of print.
Disclosure:
Saber reports no relevant conflicts of interest.
