A multicentre study presented at the recent European Stroke Organisation Conference (ESOC; 24–26 May, Munich, Germany) has found that vision recovery and an increased likelihood of early neurological improvement are among the potential benefits endovascular therapy (EVT) can offer in posterior cerebral artery (PCA) occlusion stroke. However, the same study indicated that EVT was not linked to improved odds for reduced disability, and was also associated with higher mortality and symptomatic intracranial haemorrhage (sICH) rates, as compared to medical management (MM).
Findings from PLATO—a case-control study conducted at 27 sites, and including consecutive patients with isolated PCA occlusions presenting 0–24 hours from symptom onset—were delivered for the first time by Simon Nagel (Heidelberg University Hospital, Heidelberg, Germany). Nagel and his colleagues included 1,023 patients (median age=74 years, 57.6% male) in the study, 379 (37%) of whom received EVT. The majority of PCA occlusions were either located in the P1 (41.2%) or P2 (49.2%) segments.
Regarding the trial’s co-primary endpoint, which contrasted 90-day ordinal modified Rankin scale (mRS) scores between the two groups, there was no statistically significant difference with EVT versus MM. However, Nagel did report EVT being associated with greater odds of achieving a decrease >2 points on the National Institutes of Health stroke scale (NIHSS) at 24 hours or upon discharge, as well as “complete vision recovery”, compared to MM. This was the case following adjustments for numerous comorbidities and variables, including age, sex, NIHSS score, baseline mRS, occlusion location, and whether or not intravenous thrombolysis (IVT) was administered.
The presenter further detailed a higher likelihood of an excellent functional outcome (mRS 0–1) with EVT—despite increased mortality (10.1% vs 5%) and sICH (6.2% vs 1.7%) rates versus the MM group. As such, Nagel concluded that “these results support continued enrolment into ongoing trials comparing EVT versus MM in patients with distal vessel occlusion”, referring primarily to the DISTAL, ESCAPE-MeVO and DISCOUNT studies.
A brief discussion between Nagel and session moderator Marc Ribó (Hospital Vall d’Hebron, Barcelona, Spain) culminated in an ESOC audience member suggesting that mRS is primarily focused on mobility, and may not take vision-related outcomes into account as much as it should. Nagel agreed with this view, citing it as a key motivation for vision recovery being included as a separate outcome measure in PLATO.
Findings from the PLATO study have since been published in full in the journal Stroke.
A new frontier in stroke intervention?
ESOC 2023 also saw Fouzi Bala (University of Calgary, Calgary, Canada) present late-breaking data from a sub-analysis of the AcT randomised controlled trial, which was published last year and demonstrated non-inferiority of tenecteplase versus alteplase in acute ischaemic stroke patients.
The analysis in question focused solely on patients with medium vessel occlusion (MeVO) stroke—a population not dissimilar to the one included in the PLATO study, as well as those in the aforementioned trials assessing EVT in strokes caused by more distal occlusions. At the outset of his presentation, Bala noted that the safety and efficacy of tenecteplase in MeVO stroke is “still not well studied”. Patients with baseline M2/M3, P2/P3 and A2/A3 occlusions were included in Bala and colleagues’ AcT sub-analysis. The primary endpoint was the proportion of 90-day mRS 0–1, while secondary endpoints included 90-day mRS 0–2, mortality and sICH, as well as successful reperfusion (expanded thrombolysis in cerebral infarction [eTICI] 2b–3) on first and final angiographic acquisitions.
Bala reported that, across a total of 1,577 AcT patients, 455 (28.8%) had a MeVO stroke. The primary outcome was achieved in 37.9% in the tenecteplase group compared to 34.7% in the alteplase group. In addition, rates of 90-day mRS 0–2, sICH and mortality were all similar between the two drug types. Across 87 patients (19.1%) who underwent EVT, they found a significantly higher rate of final successful reperfusion in patients who received tenecteplase (71.7%) versus alteplase (60%). However, treatment effect modification by occlusion location was also assessed, and the researchers found no heterogeneity between groups here.
As such, Bala et al concluded that intravenous tenecteplase was observed to have shown a comparable safety profile and impact on functional outcomes versus alteplase among MeVO patients included in the AcT trial.