Symptomatic intracranial artery stenosis, what is the advantage or disadvantage of medication and stent combined with medication? China's latest research is coming!

*For medical professionals only

There was no significant difference in the efficacy of stent combination pharmacotherapy and pharmacotherapy alone for symptomatic intracranial atherosclerotic stenosis

Before entering the interpretation of the corresponding author

Let's start with the study summary

Could you please tell us why you did this research?

First, there have actually been two multicenter randomized controlled studies in the field of interventional therapy for symptomatic severe intracranial artery stenosis

As the first 2 blockbuster studies in the field, it is extremely valuable, but from the current point of view, it has certain flaws in the study design:

1.

2.

3.

4.

5.
Both of the people studied were Western
.

And we Chinese or Asians, in fact, are very different from
Westerners.

For example, the proportion of stroke caused by intracranial artery stenosis is 5% to 10% in the Western population, but as high as 35% to 50%
in the Asian population or Chinese population.

Therefore, intracranial artery stenosis is actually a disease
that is highly common and unique to Asian people.

But in the first two studies, there were almost no Asian people or Chinese patients
.

Therefore, for a disease that is unique to Chinese, we actually need to do our own research to come up with Chinese data
.

This is where our CASSISS research came into
being.

Medical community

Could you please tell us about the results of the study?

We came to two conclusions:

1.
There are two intervention methods in our study: one is stent combined with drugs, and the other is simple drug treatment
.

A comparison of the two groups of people with different treatment modalities showed that the complication rate of patients, whether in the stent group or the drug group, was lower than in the
previous two studies.

It shows that stent therapy is progressing, and drug therapy is actually improving
.

2.
There is no difference between the stent group and the
drug group.

There is no difference in clinical outcomes among
the several endpoint indicators we have.

This result is different from the previous two studies, which clearly found that stent therapy is far worse than drug therapy
.

That is, after the optimization of patient selection and the limitation of the experience of the surgeon, etc
.

We conclude that the safety of stent implantation is improved, but it still does not exceed the level
of drug therapy.

In summary, pharmacotherapy remains a first-line treatment option
.

But for some special populations, we can try
more.

Medical community

What is the guiding significance of this study for the treatment of symptomatic severe intracranial artery stenosis in China at this stage?

Clinically, surgical indications for stent intervention actually depend on diagnostic modalities
.

The existing diagnostic model is actually very simple: one is based on symptoms, the second is based on the degree of narrowing of blood vessels (more than 70% is severe stenosis), and the third is that drug therapy is ineffective
.

These three conditions are met and stent intervention can be attempted
.

In terms of stent device selection: Because our study was ten years ago, only one Winspan stent
was used.

However, there are many instruments
for stent treatment of intracranial arteries.

In addition to the self-expanding stent, there are balloon expansion stents, drug-coated stents (balloons), and simple balloon expansion stents
.

In fact, these are all things that can be tried, but these other devices have not been studied
at such a high level.

Therefore, it can be selected according to the doctor's experience and the current diagnostic evidence, and it does not have to be limited to our research
.

Medical community

What are the clinical problems that remain to be solved in the treatment of intracranial artery stenosis?

I think there are two problems: the first is diagnosis
.

As I mentioned in one of my questions above, our current diagnostic model is very singular in terms of only two dimensions (symptoms and degree of
lumen stenosis).

It is inaccurate
to use these two dimensions to determine whether a patient is at high or low risk of stroke.

So we felt that the diagnostic mode
should be changed.

The diagnostic model should add two evaluation dimensions, one is the wall structure: different plaques on the blood vessel wall lead to different outcomes
.

The composition of the inside of the plaque determines whether it is easy to rupture and easy to blood clots
.

Therefore, the evaluation of the pipe wall must be a good direction in the future
.

There are several methods currently being tried in the evaluation of the tube wall: high-resolution magnetic resonance, cranial CT, and intravascular ultrasound
.

These methods are just experiments, but we feel that this is a big diagnostic direction in the
future.

There is also a new dimension of hemodynamics, that is, functional evaluation
.

The same degree of narrowing, the same plaque nature, but because each person's collateral circulation of blood vessels is different
.

The degree of decline in flow rate after blood flow across the lesion area is not the
same.

Some patients have a high degree of decline, and some have a very low degree
.

Then we will definitely intervene in those who are obviously declining
.

There are actually some ways to evaluate
the hemodynamic dimension.

For example, we have learned very mature methods from coronary hemodynamic evaluation, such as CFD, FFR, etc
.

Of course, this is only in the stage of trying to explore and study, and it has not been applied to the clinic
.

If these four dimensions (symptoms, lumen stenosis, wall structure, hemodynamics) are combined to assess the patient, we can very accurately stratify
the patient's stroke risk.

High-risk ones should actively intervene, and low-risk ones are more conservative
.

In this way, we can more accurately screen out patients who are suitable for interventional therapy and those who are suitable for conservative drug treatment
.

The second problem is treatment
.

On the one hand, interventional technologies need to be developed or upgraded, specifically: interventional surgical robots in the exploratory stage, drug-coated stents that are now in use, balloons, etc.
, and even some very new degradable stents
.

On the other hand, there is drug therapy: our current drug treatment is the initial dual antibody and statin therapy, so are there some new drugs that can further reduce the risk of stroke recurrence? But the cycle of drug development is very long, and it requires a lot of basic and mechanistic research
.

This is certainly a big direction
for drug treatment for patients with intracranial stenosis in the future.

Medical community

In your opinion, should our future research on the treatment of this disease focus on drug therapy or the optimization of endovascular stenting?

This topic has actually been debated around the world for more than 20 years
.

But neither side convinced the
other.

My personal opinion is that both treatments have their own living space
.

Even if the drug is developed, some patients, especially high-risk patients, who need to be treated with stent implantation; There are also some patients who have better drug treatment and do not need to do stent implantation
.

As a doctor in the field of neurointervention, I definitely feel that there is a lot of room for optimization in interventional instruments and diagnostic models, and after optimization, it is actually beneficial to the
entire patient population.

Professor, Chief Physician, Director of the Department of Interventional Radiology, Xuanwu Hospital, Capital Medical University, Deputy Director of the Department of Neurosurgery, Director of the Center for Cerebral Blood Reconstruction, Doctoral Supervisor
.

Vice Chairman of the Neurointerventional Professional Committee of the Chinese Medical Doctor Association; Chairman of the Neurointervention Committee of the National Health Commission Continuing Education Center; Chairman of the Ischemic Stroke Surgery Committee of the National Health and Health Commission Brain Prevention Committee; Vice Chairman of the Ischemic Stroke Intervention Committee of the National Health and Health Commission Brain Prevention Committee; Editor-in-chief of Chinese Journal of Cerebrovascular Diseases; Central Health Consultation Specialist; Vice President of Beijing Interventional Medicine Association
.

Graduated from Shandong Medical University, he studied under Professor Zhu Shugan and Professor Ling Feng, obtained a master's degree and a doctorate degree in neurosurgery, and completed postdoctoral research
at Peking University under the guidance of Professor Bao Shengde.

References:

[1] Wang Yongjun, Li Zixiao, Gu Hongqiu, et al.
China Stroke Report 2020 (Chinese edition)[J].
China Journal of Stroke, 2022(017-005).

[2] Gao P, Wang T, Wang D, et al.
Effect of Stenting Plus Medical Therapy vs Medical Therapy Alone on Risk of Stroke and Death in Patients With Symptomatic Intracranial Stenosis: The CASSISS Randomized Clinical Trial[J].
JAMA, 2022, 328(6): 534-542.