Cardiologists experienced in cardiac interventions can competently perform stroke thrombectomy after a short period of training, with outcomes comparable to those achieved by neuroradiology centers, a new study suggests.
“Using interventional cardiologists in this way will help address the huge unmet need for stroke thrombectomy that currently exists,” senior author Petr Widimsky, MD, said in an interview.
Although this may be a feasible way forward in Europe, there is strong opposition to such a proposal from U.S. neurointerventionalists.
The study, published in the April 12 issue of JACC: Cardiovascular Interventions, describes the establishment of a stroke thrombectomy program in University Hospital Kralovske Vinohrady, a large tertiary hospital in Prague, Czech Republic.
The hospital did not have a neurointerventional program until 2012 when a joint program was started involving an experienced team of cardiologists, angiologists, and one interventional radiologist who trained the cardiologists on the thrombectomy procedure.
The current paper reports on the outcomes of the 333 patients with large vessel occlusion stroke treated under this program between October 2012 and December 2019.
The decision to perform catheter-based thrombectomy was made by a neurologist and was based on acute stroke clinical symptoms and CT angiographic findings.
Results show that functional clinical outcomes, assessed via the Modified Rankin Scale (mRS) score at 3 months, did not vary significantly across years 2012 to 2019, with a favorable outcome (mRS 0 to 2) achieved in 47.9% of patients.
Symptomatic intracerebral hemorrhage occurred in 19 patients (5.7%) and embolization in a new vascular territory occurred in 6 patients (1.8%), outcomes similar to those of neuroradiology centers.
The desired clinical results were achieved from the onset of the program, without any signs of a learning curve effect, they reported.
“These findings support the potential role of interventional cardiac cath labs in the treatment of acute stroke in regions where this therapy is not readily available due to the lack of neurointerventionalists,” the authors concluded.
“Our main message is that our results were excellent from the beginning,” Dr. Widimsky said. “When centers prepare properly, they can achieve excellent results from the beginning with cardiologists who are experienced in interventional procedures and who have spent sufficient time learning about the brain.”
The authors noted that despite thrombectomy being an extremely beneficial treatment for severe stroke, many eligible patients remain untreated, largely because of a lack of neurointerventionalists in many regions worldwide. They estimate that about 15% of all stroke patients are eligible for thrombectomy but only around 2% of stroke patients in Europe actually receive such treatment.
Dr. Widimsky, an interventional cardiologist, first thought of the idea of using cardiologists to perform stroke thrombectomies after a good friend and colleague suffered a severe stroke in 2010.
“This made us realize that our hospital needed to be more active in the stroke field,” he said. “We decided that we needed to start doing stroke interventions.”
But the major problem was the lack of neurointerventionalists.
“There are not enough neurointerventionalists in Europe. Interventional cardiologists can perform thousands of procedures every year whereas a neurointerventionalist will at best perform hundreds a year. It is quicker and simpler to train the cardiologist to do it,” Dr. Widimsky said.
They hired one neurointerventionalist to lead the program. “He was our tutor, he taught us his skills,” Dr. Widimsky said. “The cath lab is open 24/7, but if we only have one neurointerventionalist we cannot offer a 24/7 service for stroke thrombectomy. But if we merge with cardiology then we can,” he added.
Their hospital is a very busy center for myocardial infarction, percutaneous coronary intervention, and carotid stenting, he noted. “It is not difficult to make the step from that to stroke thrombectomy. Interventional cardiologists are used to performing carotid and coronary artery stenting. Stroke thrombectomy is a similar technique. The thrombectomy procedure is different from coronary angioplasty but it is not more difficult. Actually, I think coronary angioplasty can be more difficult.”
Dr. Widimsky explained that cardiologists need to learn about the brain anatomy and physiology and learn the stroke imaging techniques. “I spent 1 month in the U.S. learning stroke interventions working with simulators,” he said. “I think interventional cardiologists can learn what they need to know in about 6 months. I would recommend they should watch about 50 procedures and perform at least 25 under supervision.”
He said this model is the way forward and hopes it will become routine. Thrombectomy is “tremendously effective” in improving outcomes in severe strokes, with a number needed to treat (NNT) of just 2.6 to prevent long-term disability in one patient, he said, while other procedures can have NNTs of 50 or more.
“But millions of patients with acute severe stroke are not getting this life-changing treatment,” he added. “We must do everything we can to make this service available to as many patients as possible.”
Dr. Widimsky acknowledges that there has been opposition to this idea from the neurointerventionalist professional bodies but this has lessened recently, at least in Europe. And a program that allows interventionalists with experience in extracranial carotid and vertebral endovascular procedures to “fast-track” technical training has now been proposed.
“There is an enormous unmet need for stroke thrombectomy in Europe, with some countries needing to increase the number of procedures done by 10 or 20 times. These include the U.K., Sweden, Italy, Spain, and Portugal. This cannot be done without cardiology,” Dr. Widimsky said.