Interventional radiologists could help alleviate an acute shortage of trained physicians and specialized facilities throughout the world to treat stroke patients, says the Society of Interventional Radiology, the Cardiovascular and Interventional Radiology Society of Europe, and the Interventional Radiology Society of Australasia. The groups published a joint position statement in the February issue of the Journal of Vascular and Interventional Radiology recommending that interventional radiologists be trained to perform endovascular thrombectomies (EVT).
Thrombectomy increases survival rates in acute ischemic stroke. EVT is proven to reduce the likelihood of resulting disabilities and speeds function recovery. However, EVTs need to be initiated without delay to achieve maximum benefit.
Stroke is a leading cause of death and permanent disability throughout the world, with an estimated 15 million cases leading to an estimated 5.8 million deaths, according to the World Stroke Organization.1 The U.S. Centers for Disease Control and Prevention reported in 2018 that there are approximately 795,000 annual cases of stroke in the United States, causing an estimated 140,000 deaths.2 In the United States annually, an estimated 100,000 stroke patients may be eligible for an EVT, but currently only 231 certified comprehensive and thrombectomy-capable stroke centers exist.3 The situation is even more dire in Europe.
Interventional radiologists have many of the skills and the knowledge needed to perform EVT, and with additional training in stroke imaging, clinical neurology, care of the stroke patient, and the EVT procedure, could successfully do so.
To determine an efficient and sustainable way to expand access to thrombectomy, researchers from Johns Hopkins University in Baltimore, developed an interventional radiology (IR) stroke team at Suburban Hospital, a community hospital in Bethesda, MD. The team consisted of four interventional radiologists trained by a neurointerventional radiologist for six months. The team was available 24/7, with the neurointerventional radiologist traveling by helicopter to the hospital for every case during the training period.
Kelvin Hong, MD, associate professor and division chief of IR at Johns Hopkins University, described the program in a scientific session at the SIR annual meeting in Austin, TX in March. Dr. Hong said thrombectomy treatment is currently available to only 2% to 3% of eligible patients in the U.S., and “that our model of training board-certified interventional radiologists cane expand access to quality, evidence-based care, and reduce the lifelong disability associated with stroke.”
The team wanted to change the dynamic in stroke care by transporting a specialist to perform the care instead of transporting medically fragile patients. They designed a program to provide the training and organization necessary to bring 24/7 highly trained stroke interventional radiologists as rapidly as possible.
Dr. Hong told Applied Radiology that initially, “Suburban had the equipment necessary to perform thrombectomy but no neurointerventional experts on staff to provide the care. In order to better serve patients and reduce time to intervention, it was decided to helicopter a neurointerventional radiologist to Suburban instead of the patient to Baltimore, which would have added more time to the process in a situation when time is literally brain.”
For approximately two-thirds of the month, the neurointerventionalist would come in for cases; for the rest of the time, he would be on site proctoring cerebral angiograms and other neurovascular procedures, Dr. Hong said.
“In this process, we decided to also train IRs at Suburban Hospital to independently treat stroke patients,” he explained. “Through in-person proctoring, the IRs were able to obtain these skills over the course of six months, at which point Dr. Hui was confident they had the necessary skills and proficiency to perform the intervention without him present.”
After the IRs began to treat independently, researchers measured the technical success of the thrombectomies performed in 35 stroke cases using the Thrombolysis in Cerebral Infarction (TICI) scale. They found no differences compared to the 2016 HERMES meta-analysis of EVTs performed by other practitioners, such as neurosurgeons and neurointerventional radiologists. The 14% mortality in the first 90 days after the procedure was similar to the 15.3% among patients at stroke centers in the HERMES trial. However, the median interval from symptom onset to the point when blood flow was restored was 325 minutes compared to 285 minutes.
Dr. Hong explained that the time difference relates to the “newness” of the program.
“When a new program starts up, it takes a little time to optimize the multifaceted pre-procedure evaluation process that gets the patient from the emergency room to a diagnosis to screening for whether they’re a candidate for thrombectomy to receiving the treatment,” he said. “Time between onset, PSC arrival, and Suburban arrival are not in direct control of our hospital; improving the EMS. Part of the delay is in the relative lack of coordination with EMS and the outlying hospitals. This is the first 24/7 stroke program in the county; developing systems coordination is part of this process.”
The second year of the program will focus on evaluating technical outcomes and time metrics, aiming to improving efficiency and optimization. Dr. Hong said his team will fully document the progress of Suburban Hospital in performance measures, procedure times, and outcomes in keeping with published stroke trials. The team hopes that their program can be adopted by other hospitals.
Interventional radiologists: Performing EVTs to treat ischemic stroke patients. Appl Radiol.