Study: Lowering blood pressure after clot removal may not be safe; should be individualized

The University of Cincinnati's Eva Mistry, MBBS, national principal investigator and lead author of the phase-2 BEST-II trial, presented findings Feb. 10 at the American Stroke Association’s International Stroke Conference 2023. The study results were published in JAMA Sept. 5.

In the BEST-II trial, researchers led by Mistry enrolled 120 patients (with an average age of 70 years, 57% female) who had an acute ischemic stroke and successful endovascular treatment at one of three urban comprehensive stroke centers between January 2020 and February 2022.

Forty patients were randomly assigned to have their systolic blood pressure lowered to a target of less than or equal to 180 mm; 40 patients were to be lowered to a systolic blood pressure of less than 160 mm; and 40 patients were targeted to reach a systolic blood pressure of less than 140 mm.

Patients were treated with a blood pressure medication called nicardipine, administered intravenously, started within one hour after endovascular treatment and given for 24 hours if their systolic blood pressure was above the target they were assigned. Researchers wanted to assess whether lowering blood pressure may cause harm to brain tissue, which is particularly vulnerable during the 24 hours after a stroke, and to assess disability 90 days later.

“Although the study did not find a significant evidence of an unequivocal harm of lower blood pressure targets in this population in terms of worsening size of stroke or increasing disability, the trends indicated that there may only be marginal benefit of lowering post-endovascular treatment blood pressure on patients’ long-term disability," Mistry said. "In fact, there was indication that lowering the blood pressure after thrombectomy may worsen patients’ long-term disability.”

Mistry said the study indicates that in most cases, patients' blood pressure should be allowed to be auto-regulated after endovascular treatment. Individual patients may require the lowering of blood pressure due to specific conditions, but it should be customized and not used as a blanket practice, she said.

“There should be individual patient decision making, such as if there are other medical reasons to lowering the blood pressure or if there are signs of significant bleeding in the brain," Mistry said. “Health care professionals should be cautious when lowering blood pressure after endovascular treatment, as there are some signs that blood pressure that’s too low may be harmful,” Mistry said.

The study’s limitations include the small number of patients involved in the trial. Additionally, because the trial was conducted at three centers, the results may not apply to stroke patients treated elsewhere.

Featured photo at top of Dr. Mistry with a patient. Photo/Andrew Higley/UC Marketing + Brand.

Study co-authors are Kimberly Hart, PhD; Larry Davis, MD; Yue Gao, MS, MEd; Charles Joseph Prestigiacomo, MD; Shilpi Mittal, MD; Tapan Mehta, MD; Hayden Lafever, PhD; Pablo Harker; Hilary Perez; Kalli Beasley, MPH; Neeharika Krothapalli, MD; Emily Lippincott, MD; Heather Stefek, MD; Michael Froehler, MD, PhD; Rohan Chitale, MD; Matthew Fusco, MD; Aaron W. Grossman, MD, PhD; Peyman Shirani, MD; Matthew Smith, MD; Matthew N. Jaffa, DO; Sharon D. Yeatts, PhD; Gregory W. Albers, MD; Jonathan Wanderer, MD, MPhil; Juliana Tolles, MD; Christopher Lindsell, PhD; Roger Jay Lewis, MD, PhD; Gordon R. Bernard, MD; and Pooja Khatri, MD, MSc. The list of authors’ disclosures is available in the abstract.

The National Institute of Neurological Disorders and Stroke, a division of the National Institutes of Health, funded the study.

A version of this release was first published by the American Heart Association under the title "Lowering blood pressure after clot removal may not be safe; should be individualized." Read the AHA release.