Quantifying Access to Mechanical Thrombectomy for Stroke

Illustration of man holding his head in pain
Article Summary
  • The Mechanical Thrombectomy Access Score (MTAS) assesses how well people in a given region can access this standard of care emergency stroke treatment.
  • Dr. Dileep Yavagal says globally, the MTAS is “dismally low.”
  • MTAS score, then, is the first method to quantify mechanical thrombectomy access and can be used to identify regions of greatest need.

It’s about equitable access.

It’s about saving lives.

It’s about the first scoring system to help increase the use of mechanical thrombectomy to treat large vessel occlusion stroke worldwide.

The Mechanical Thrombectomy Access Score (MTAS) was created by faculty at the University of Miami Miller School of Medicine, the Miami Herbert Business School and other leading institutions. It quantifies 12 factors associated with how well people in a given region can access this standard of care emergency stroke treatment.

“The access to thrombectomy is dismally low globally, at less than 5%. This should be quite shocking for a brain-saving, disability-sparing and life-saving therapy,” said Dileep Yavagal, M.D., a professor of clinical neurology and neurosurgery and director of interventional neurology at the Miller School.

Devising a Method to Evaluate Access

The score is the first of its kind, said Dr. Yavagal, who has been integral to both the creation of MTAS and the research behind it.

In a Circulation study, Dr. Yavagal and fellow researchers quantified global access to mechanical thrombectomy and disparities by country, and revealed the most salient factors affecting mechanical thrombectomy access. The researchers estimated worldwide access to mechanical thrombectomy at a median of 2.8 percent in 2020. In the United States, it was 32 percent.

Dr. Dileep Yavagal in white clinic coat
Dr. Dileep Yavagal is part of the first effort to quantify access to mechanical thrombectomy for stroke.

Dr. Yavagal used that study as basis to identify the most relevant attributes for the MTAS scoring system, starting with a literature review on access to mechanical thrombectomy. They narrowed down an initial 2,864 abstracts to 121 published studies. Next, collaborators identified the 12 most relevant factors across three main pillars of access: informational, physical and financial.

Finally, researchers weighted factors like prehospital large vessel occlusion screening, emergency department stroke expertise or telestroke availability, device availability, stroke imaging protocols, insurance coverage and more to reach a final score from 0 to 36.

The full study results were published in the prestigious American Heart Association journal Stroke. The work represents the first tool to quantify barriers to global mechanical thrombectomy access. 

An International Perspective on Stroke Care

The idea for MTAS score came from Arun Sharma, Ph.D., a professor in the Miami Herbert Business School. Dr. Sharma gave a lecture on treatment access in general, which got Dr. Yavagal thinking about access to stroke care.

Dr. Yavagal founded Mission Thrombectomy, a global peer network and campaign to improve stroke care access worldwide sponsored by the Society of Vascular and Interventional Neurology (SVIN).

Dr. Yavagal’s international perspective on stroke care informs his work in Miami. He attended medical school and completed a residency in internal medicine in India before coming to the United States.

“I had seen a lot of stroke patients in India,” he said. “I started to think about how patients in India or other lower- and middle-income countries would get this treatment once we established thrombectomy as the first-line treatment and standard of care in 2015.”

These countries have stroke burdens four to five times greater than high-income countries.

In terms of the next steps, MTAS will be put to the test in validation studies planned by Mission Thrombectomy to verify if it genuinely predicts access and whether it will be helpful in prioritizing interventions leading to improved access.


Tags: Department of Neurology, Dr. Dileep Yavagal, healthcare access, mechanical thrombectomy, neurology, stroke, stroke care guidelines, thrombectomy, USNWR Neuro