In stroke patients undergoing a mechanical thrombectomy procedure, access via the radial artery may be non-inferior to access through the femoral artery in terms of final recanalisation-related outcomes. However, reduced procedural delays associated with the latter mean transfemoral access may still be favourable as a default, first-line approach, according to the authors of a recent study.
Writing in the journal Stroke, Manuel Requena (University Hospital Vall d’Hebron, Barcelona, Spain) and colleagues detail that—between September 2021 and July 2023—they conducted a randomised clinical trial at their centre to directly compare transradial and transfemoral thrombectomy approaches.
“Transfemoral access is predominantly used for mechanical thrombectomy in stroke patients with a large vessel occlusion,” they explain. “Following the interventional cardiology guidelines, routine transradial access has been proposed as an alternative, although its safety and efficacy remain controversial.”
Against this backdrop, Requena and colleagues sought to evaluate the potential non-inferiority of a radial access approach, as compared to a femoral access approach, doing so via an investigator-initiated, single-centre, evaluator-blinded trial whereby 120 patients were initially assigned to one of the two techniques. Specifically, stroke patients undergoing thrombectomy, with a patent femoral artery and a radial artery diameter ≥2.5mm, were randomised on a 1:1 basis into transradial (n=60) and transfemoral (n=60) groups.
The binary outcome that served as the primary endpoint for their study was the rate of successful recanalisation—defined as an expanded thrombolysis in cerebral infarction (eTICI) score of 2b–3 and assigned by blinded evaluators. Requena and colleagues note that they established a non-inferiority margin of -13.2%, considering an acceptable reduction of 15% in the expected recanalisation rates.
Ultimately, 116 patients with a confirmed intracranial occlusion on initial angiogram—58 in each group—were included in the trial’s intention-to-treat analysis. The aforementioned outcome of successful recanalisation was achieved in 96.6% of patients in the radial access group (n=56) and 87.9% in the femoral access group (n=51). Stemming from this, the researchers found an adjusted, one-side risk difference of -5% that indicated non-inferiority of transradial versus transfemoral access in the trial (95% confidence interval [CI], -6.61% to 13.1%).
Another key factor measured in Requena and colleagues’ analysis related to procedural delays. Their study revealed a median time from angiosuite arrival to first thrombectomy attempt of 41 minutes in the radial group (interquartile range [IQR], 33–62 minutes) and 30 minutes in the femoral group (IQR, 25–37 minutes; p<0.001). A similar trend suggesting increased procedural delays with radial-access thrombectomy was seen in terms of median time from angiosuite arrival to recanalisation—59.5 minutes with radial (IQR, 44–81 minutes) versus 42 minutes with femoral (IQR, 28–74 minutes; p<0.05).
Finally, regarding complication and conversion rates, the authors relay that one severe, access-related complication occurred in each group, and there was no statistically significant difference in the rate of access conversion between the two, at 12.1% with radial (n=7) and 8.6% with femoral access (n=5; p=0.751).
“In our study, radial access was associated with longer procedural time, without any advantage in terms of safety,” Requena told NeuroNews. “These results must be taken with caution, because it is an unpowered trial to detect safety differences between groups. Radial access for selected patients may be the first-line approach, despite our results, but we have no data to defend radial access as a default for all mechanical thrombectomy patients.”
These data from what has been dubbed the ‘SFERA’ trial were originally presented at the 2024 International Stroke Conference (ISC; 7–9 February, Phoenix, USA), before being published in Stroke by Requena and colleagues last month.
