Stroke Treatment: Comparing tPA and Mechanical Thrombectomy

In cases of ischemic stroke, endovascular therapy with mechanical thrombectomy may result in higher functional outcomes and higher rates of angiographic revascularization, when compared with standard care with the use of intravenous tissue plasminogen activator (tPA); however, there is little difference in symptomatic intracranial hemorrhage or all-cause mortality rates with 90 days of treatment. Jetan Badhiwala, MD, of the Division of Neurosurgery at the University of Toronto in Canada and colleagues, completed a meta-analysis of the available literature. The results of their work were published in the Journal of the American Medical Association (JAMA) on November 3, 2015.

The researchers conducted this analysis in order to “assess the association between endovascular mechanical thrombectomy and clinical outcomes.” They were particularly interested in functional outcomes including revascularization, intracranial hemorrhage, and mortality. They also investigated whether or not other factors, such as imaging, patient, treatment, or study-related, were associated with better outcomes.

Through a careful selection process, the researchers identified 4,193 studies, of which 8 were trials. There were 2,423 patients in those studies, and 1,313 of them underwent endovascular therapy and 1,110 received standard medical treatment. The statistical analysis showed that endovascular therapy “was associated with significantly higher rates of functional independence at 90 days.”

Although the patients who received endovascular therapy were more functionally independent at 90 days, “there was no significant difference in rates of symptomatic intracranial hemorrhage within 90 days between groups.” The researchers also found that there was no significant difference in mortality rates for the two groups.

An interesting point the researchers bring up is that “endovascular therapy is often considered, and evaluated as, a single treatment modality.” In fact, there are many different combination therapies and strategies that are used with endovascular therapy. For instance, in this analysis, “the relative benefit associated with endovascular therapy was increased by concomitant use of intravenous tPA.”

The researchers conclude that more trials are necessary to “systematically study the relationship of patient-, disease-, and treatment-related variables.” Such studies will help care providers develop clinical practice guidelines that have the best chance for positive outcomes, are safe, and are cost effective.