Exactly

Stent occlusion is one of the most important problems of stents that use thrombolytic drugs to solve this issue. In more advanced cases, the drug is placed on a stent so that the drug is released slowly over a long period of time to prevent clots from forming.

In fact, prevention precedes treatment

However, prevention may not always be effective

Is there a cure? How to remove a clot after creating a stent

Medication can be effective

Such as streptokinase

But blood flow can move the drug molecules away from the clot area in the stent, and this will greatly reduce the efficiency of the drug.

Yes, that's right. One of the best things to do is to use mechanical or laser methods to reopen the stent. Because drugs are not very effective. Stents can be reopened with methods such as rotating tools or lasers

Is it possible to use the tool to temporarily block the stent?

Many problems can occur. This may be one of the problems. Perhaps one of the best ways is to use nanoparticles or nanobots to remove clots inside the stent. Of course, it is a bit imaginative, but I think it is a good ground for research

Stent thrombosis is defined as thrombotic occlusion of a coronary stent, which is a major complication after stent deployment across a coronary artery lesion (a procedure called PCI). It is largely preventable -- by prior administration of loading anti platelets, adequate anticoagulation during procedure (keeping ACT above 250s). It may be related to inadequate stent expansion, improper anti coagulation and suboptimal angiographic results.

For removing thrombus (or clot in stents), various pharmacologic (e.g. systemic and /or intracoronary GP IIb/IIIa), mechanical devices (e.g - thrombosuction catheters) are used.

Is it possible to use ether catheterization or thrombectomy in stents?

Yes, these devices are being used both for drug delivery (e.g. GP IIb/IIa through a microcatheter within or beyond thrombus/clot in the stent) and to suck out the thrombus (clot).

I am researching a new way to remove a clot inside a stent. That the clot is destroyed by abrasion of magnetic nanoparticles in the heart stent. But I am an engineer and I do not have a medical vision. Can you evaluate this method?

In case of acute thrombosis regardless of the location inside the stent or beyond the stent, there are well-established methods of thrombus aspiration and FDA-approved catheters for thrombectomy: Penumbra, AngioJet Boston Scientific; Export catheter, Medtronic, etc.

Delayed stent failure with organized thrombus treated as any occlusion.

Thank you for your good explanation. Can a catheter be inserted into all vessels? And is the size of the catheters not a problem for the capillaries?

Good question! The aspiration catheters are compatible with coronary guide catheter 6, 7 F and have low profile- max tip diameter 1.5-1.9 mm. So, could work anywhere above 2.0mm

No need to delivering them to capillaries. Coronary microembolization is completely different entity, is represented by slow/no-reflow and treated by meds (nitro, hepari, IIb/IIIa inhibitor, etc).

In fact, aspiration microcatheters are one the iatrogenic causes of microembolization.

Speaking about the saphenous venous grafts sub-occlusive lesions, the distal filter placement is the standard of care.

The first step should be the dissolution of the clot, so When the tip of the catheter reaches the clot, a clot-dissolving drug such as tissue plasminogen activator is infused into the clot through the catheter. Usually, it will dissolve in a day or two. Then, later, When a catheter containing a collapsed stent retriever reaches a clot blocking the artery, the stent moves out of the catheter, unfolds to form a 3D mesh tube, captures the blood clot, and retracts back into catheter with its catch.

thank you