- The TESLA trial tested the concept of stroke thrombectomy on large-core infarcts with a noncontrast CT-alone selection paradigm to lower the barrier for imaging and patient selection.
- While primary results at 90 days did not meet statistical superiority, extended follow-up to 1 year did significantly favor endovascular therapy over medical management alone for functional outcomes.
- The investigators suggested that the between-group difference is related to the severe natural history of untreated large-core tissue decay, hence the diverging recovery or decline trajectories.
In the TESLA trial, stroke outcomes took a turn for the better following swift mechanical thrombectomy for large anterior circulation infarcts identified without advanced imaging.
In an extended analysis of the trial at 1 year, patients treated with CT-selected endovascular therapy (EVT) for large-core infarcts had improved functional outcomes compared with those treated with medical management alone, as measured by mean utility-weighted modified Rankin Scale (mRS) scores (3.65 vs 2.78, bayesian adjusted mean difference 1.18 points, 95% credible interval 0.42-1.93; posterior probability of superiority P=0.999).
Patients receiving EVT versus medical management alone also had a higher likelihood of functional independence (mRS score 0-2; 23.6% vs 6.8%, P<0.001) and independent ambulation (mRS score 0-3; 35.4% vs 18.0%, P<0.001) at 1 year, reported Albert Yoo, MD, PhD, of California Neurointerventional Surgeons in Riverside, and colleagues.
“Although functional independence in the IAT [intra-arterial thrombectomy] group numerically increased between 90 days and 1 year, it declined in the MM [medical management] group, which may reflect the severe natural history of untreated large-core tissue decay, delayed deconditioning, unmeasured rehabilitation intensity difference between groups, or baseline imbalances, such as age,” they wrote in a research letter in JAMA.
“These exploratory observations complement the 12-month data reported in the SELECT2 and TENSION trials, supporting that early large-core reperfusion may facilitate prolonged neuroplastic remodeling up to 1 year post stroke,” they added.
The favorable 1-year results of TESLA put the study more in line with these other trials, after its main analysis had indicated neutral results for EVT in the short term.
TESLA stands alone as the only EVT trial to extend the enrollment window to 24 hours while requiring only noncontrast CT for infarct size estimation and CT angiography for diagnosis of target vessel occlusion without more advanced imaging techniques to identify eligible patients with large-core strokes. Of note, with the more pragmatic entry criteria, there was a relatively long median of 11.5 hours from stroke onset to randomization in this study.
The open-label trial was conducted across 47 U.S. stroke centers and included adults presenting within 24 hours of last known well with an NIH Stroke Scale score of 6 or higher, internal carotid artery or middle cerebral artery occlusion, an Alberta Stroke Program Early Computed Tomography Score of 2 to 5 on baseline CT, and a premorbid mRS score of 0 to 1.
Yoo and team randomized 302 patients to medical management with or without intra-arterial thrombectomy; ultimately, 300 were included in the intention-to-treat analysis. Complete 1-year functional data were available for 277 people, among whom baseline profiles were balanced between groups, though the EVT group was slightly younger (median age 66 vs 68) and more likely to have diabetes (28.5% vs 16.8%).
As part of the exploratory analyses, the study authors also found that patient-reported quality of life was better in the EVT group at 1 year, as measured by the 100-point European Quality of Life 5 Dimensions, 5 Levels (EQ-5D-5L) health questionnaire (average score 60.3 vs 49.3, P=0.003).
All-cause mortality rates were not significantly different between groups (43.1% vs 46.6%, P=0.42).
As for potential harm, EVT had been associated with excess symptomatic intracranial hemorrhage at 24 hours, as previously reported (4.0% vs 1.3%).
Yoo and colleagues stressed that the present report covered exploratory analysis and may have been biased by unblinded postprocedural rehabilitation intensity and asymmetric 1-year attrition, as follow-up was complete for 144 patients in the EVT group and 133 controls. External validity to lower-resource regions remains unestablished, they added.
“Nevertheless, these descriptive data suggest longer-term benefit associated with thrombectomy in large-core stroke, indicating that a [noncontrast] CT-alone selection paradigm warrants further study as a lower-barrier strategy for global stroke systems,” the investigators concluded.
