Illustration of human head and brain

Physically removing a blood clot causing a stroke combined with clot-busting drugs improves the outcome of patients more than giving clot-busting drugs alone, according to research presented at the American Stroke Association’s International Stroke Conference 2016.

Most trials investigating whether it is beneficial to add mechanical clot retrieval (thrombectomy) to the clot-busting drug tissue plasminogen activator (tPA) require that patients have evidence of salvageable brain tissue on imaging. In contrast, the French multicenter trial THRACE only used imaging to verify the presence of a clot in a large brain artery, so it enrolled a wider group of patients that included some with a poorer prognosis. Treatment was started within four hours of symptom onset. The trial was halted early after an intermediate analysis showed clear benefit for thrombectomy.

Among the final results:

  • After three months, 106 of 200 patients (53 percent) who received tPA plus thrombectomy were functionally independent, compared with 85 of 202 patients (42 percent) who received tPA alone.
  • Patients who received thrombectomy were no more likely to die or experience bleeding in the brain than those receiving tPA alone.
  • Nearly 30 percent of patients with poorest baseline prognosis achieved functional independence whatever the treatment group.

“The result is better in the thrombectomy group but the number of patients in each treatment group was too small to reach statistical significance,” said Serge Bracard, study author and head of the department of Diagnostic and Interventional Neuroradiology, University Hospital Nancy in France. “Combining intra-arterial treatment with IVT thrombolysis appears to be beneficial for all stroke patients regardless of age, sex, clinical severity or intracranial location of the occlusion.”

Editor’s Note: This story was written when the time limit on mechanical clot removal was six hours. New guidelines released in January 2018 allow some carefully selected patients to receive mechanical thrombectomy up to 24 hours after stroke symptoms begin.