Intensive blood pressure lowering after thrombectomy shows no benefit in reducing intraparenchymal haemorrhage a marker of ischaemia-reperfusion injury, a randomised controlled trial has shown.

French researchers conducted the BP-TARGET trial in 324 patients with acute stroke with a target of reducing systolic blood pressure to 100–129 mm Hg after successful endovascular therapy in an intervention group.

Using IV nicardipine as an antihypertensive, the mean systolic BP achieved during the first 24 hours after reperfusion was 128 mm Hg in the intensive target group and 138 mm Hg in the standard target group.

However the intensive target group showed no difference in the primary outcome of radiographic intraparenchymal haemorrhage rates at 24–36 h (42%) as compared with the standard care group (43%).

Secondary endpoints, such as the proportion of patients with symptomatic intracerebral haemorrhage, mortality at three months (7% vs 4%), and number of hypotensive events (8% vs 3%), were all higher in the intensive target group than the standard target group but the differences were non-significant

Published in Lancet Neurology, the findings stand in contrast to previous observational studies that had shown an association between elevated systolic BP and worse functional outcome or intraparenchymal haemorrhage occurrence, the study investigators said.

The negative results might have been due to the modest difference in systolic BP of 10 mm Hg between groups, or perhaps because BP was not lowered to a point low enough to make a difference, such as the 120mmHg threshold suggested by some researchers.

“Whether blood pressure has a direct negative affect on outcomes or is an important, but still indirect, marker of worse outcomes is still an unanswered question,” they wrote.

The findings also highlighted the difficulty in reducing systolic BP in the stroke unit environment and the question of whether BP variability was more important than absolute lowering of BP to reduce haemorrhage, they said.

“Overall, these results point out the absence of efficacy of an intensive blood pressure lowering strategy on radiographic intraparenchymal haemorrhage rates after successful endovascular therapy for acute ischaemic stroke,” they concluded.

“BP TARGET challenges the current practice to lower blood pressure after successful reperfusion and underlines the need for further trials in this field,” they added.

An accompanying editorial said the BP-TARGET trial should be viewed as a pilot study as it did not have the power to detect small effect sizes and did not evaluate potentially more did not evaluate parameters, such as blood pressure fluctuations or stroke volume.

“We now await trials with higher adherence and easier interpretation of results than those of BP-TARGET, and whose findings should help to develop guidelines for blood pressure management in patients with large vessel occlusion after endovascular therapy,” the authors wrote.