In Stroke, High Systolic Blood Pressure Should Not Delay Endovascular Thrombectomy

In patients who experience an ischemic stroke, systolic blood pressure (SBP) at hospital admission should not influence decision-making for endovascular thrombectomy procedures. These are the findings of a post hoc meta-analysis published in The Lancet Neurology.

Most patients with acute ischemic stroke present with elevated SBP. Previous research on intravenous thrombolysis and endovascular thrombectomy has established a link between high BP and worse outcomes after ischemic stroke. However, this does not suggest that BP impacts the effect of these procedures on patients’ outcomes.

For the meta-analysis, researchers sought to investigate the influence of admission SBP on functional outcome and on the effect of endovascular thrombectomy. They used pooled individual patient data from the 7 randomized trials within the Highly Effective Reperfusion Using Multiple Endovascular Devices (HERMES) collaboration.

In these 7 studies, all patients with anterior ischemic stroke were randomly assigned to endovascular thrombectomy (mainly with the use of stent retrievers) or standard medical therapy (control) from June 1, 2020, through April 30, 2015.

The primary study outcome was 90-day functional outcome, according to the modified Rankin Scale (mRS). Secondary study outcomes included the following:

• Functional independence (mRS ≤2) at 90 days
• National Institutes Health Stroke Scale (NIHSS) score 24 hours following randomization
• Successful reperfusion following endovascular thrombectomy
• Follow-up infarct volume on noncontrast computed tomography (CT) or magnetic resonance imaging scan at 12 hours to 2 weeks following randomization    

Safety outcomes included mortality within 90 days and any symptomatic intracranial hemorrhage reported within this time frame.

The study included a total of 1,753 participants — 867 of whom were enrolled in the endovascular thrombectomy arm and 886 of whom were in the control arm. A nonlinear association between SBP and functional outcome was observed with an inflection point at 140 mm Hg: 42% (732 of 1753) of participants had an SBP of <140 mm Hg, whereas 58% (1021 of 1753) of participants had an SBP of ≥140 mm Hg.

Patients with an SBP of ≥140 mm Hg at hospitalization were more likely to be older, as well as to have a history of atrial fibrillation, hypertension, and hyperlipidemia, than were those with an SBP of <140 mm Hg at admission. No differences were observed in baseline NIHSS and Alberta Stroke Program Early CT Score (ASPECTS) between patients with an SBP of ≥140 mm Hg at hospitalization and those with an SBP of <140 mm Hg at admission.

Researchers found that in patients with an SBP of ≥140 mm Hg, SBP at hospital admission was associated with a worse functional outcome (adjusted common odds ratio [acOR], 0.86 per 10-mm Hg increase in SBP; 95% CI, 0.81-0.91). In contrast, among individuals with an SBP of <140 mm Hg, there was no association observed between SBP and functional outcome (acOR, 0.97 per 10-mm Hg increase in SBP;
95% CI, 0.88-1.05). Further, no statistically significant interaction was reported between SBP and the effect of endovascular thrombectomy on functional outcome
(P =.96).

In the endovascular thrombectomy arm, the median mRS at 90 days was lower among individuals with an admission SBP of <140 mm Hg compared with those with an admission SBP of ≥140 mm Hg. Additionally, the percentage of participants with functional independence in the endovascular thrombectomy cohort was significantly higher among those with an SBP of <140 mm Hg at hospitalization compared with those with an SBP of ≥140 mm Hg at admission (55% vs 43%, respectively; P =.0002).

Study limitations included the fact that the analyses were based on a single SBP measurement, with neither diastolic BP nor mean arterial pressure readings available. In addition, individuals with very high or uncontrolled BP upon hospitalization were not included in the endovascular thrombectomy trials.

“[A]dmission SBP should not form the basis for decisions to withhold or delay endovascular thrombectomy for ischaemic stroke, but randomised trials are needed to further investigate this possibility,” the researchers acknowledged.

“Based on current available evidence and the benefit of early treatment with endovascular thrombectomy in patients with acute ischaemic stroke due to a large vessel occlusion in the anterior circulation,” the authors indicated, “we believe that the recommendations by the ESO and AHA/ASA [European Stroke Organisation and American Heart Association/American Stroke Association] guidelines to withhold or delay endovascular thrombectomy in patients with admission blood pressure above
185/110 mm Hg deserve revision,” they concluded.

Disclosure: Some of the study authors have declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.