|Title of Invention||
"A FLOW CONTROL DEVICE"
|Abstract||This invention is generally relates to stents and more particularly to lined inflatable and deflatable stents (the stent is dilatable and its lining is either inflatable or dilatable) that is introduced inside vessels to control the blood (or other fluids) flow.|
|Full Text||The present invention relates to a flow control device. The present invention is directed to the field of intravascular stents.
The document US 6293968 Bl describes an inflatable vascular stent which incorporates fine conduits of synthetic material in a meshwork like structure forming a tubular vascular prosthesis. The conduits provide for inflating and deflating the meshwork to deploy the stent, adjust its supporting force and for repositioning or removing the stent, if needed. Following insertion of the stent into the treatment zone, the meshwork structure is inflated to expand the stent against the vasculature wall. Importantly, the inflation pressure is controllable to regulate the supporting force of the stent as it conforms to the shape of the vasculature. The stent is combined with a graft. The graft is a hollow tube of prosthetic material such as Dacron.
This invention is about mounting a non reactive inflatable tissue on an appropriate size intravascular stent to control the flow distally. This created stent is then placed on the intended vessel per catheter. This tissue can be put in different designs:
1. A tire in a wheel with a central opening.
2. In the form of successive openings of different sizes to allow for future change in the size of the stenosis imposed to the circulation by interventions e.g. balloon catheters to remove one of the narrowings for example.
3. Crescentic or boggy masses of enclosed tissue that can be compressed later on e.g. by a balloon to modify the gradient across the stenosis produced e.g. pulmonary artery.
4. A design similar to naturally occurring stenotic valves.
5. A stenotic absorbable material to allow for natural progressive dilatation.
6. A stenotic material that swells with time to allow for progressive narrowing.
According to the present invention, there is provided a flow control or flow limitation device comprising a stent to be placed inside a vessel, and a lining made of non-reactive material mounted inside that stent, wherein said lining is inflatable and deflatable to control the flow through.
Reference to accompanying drawings
Figure 1, illustrates a vertical section of the lined balloon mounted stent  of the present invention. Here, the vessel wall of the flow control device is shown from the outside. Also, stent  with the inflated lining balloon shows the narrowing of the lumen.
Figure 1 also illustrates cross section of the lined balloon mounted stent with the inflated balloon producing reduction of the lumen.
Figure 2 illustrates and explains that balloon lining of the present invention in different embodiments may be designed in different shapes  . In particular, Figure 2 illustrates a vessel wall from the outside, the stent from the inside, and the lining balloon inflated with a different shape of the narrowing.
The flow control or flow control limitation device may be fixed.
The stent may be made of metallic material, made of plastic material, totally inflatable, shaped as a ring, of tubular shape, of cylindrical shape, of conical shape and/or pentagonal shape.
The lining may be made of PTFE.
The stent may be adapted to be placed inside a blood vessel. , airways, urinary passages, gastrointestinal passages, and/or industrial pipes.
All these designs can be inflated or deflated to control their size. During the procedure and sometimes later as well. The inflation can be done by carbon dioxide, air or even different fluids e.g. normal saline. The addition of the ability to compress the narrowed segment later on by dilating balloons is gain feasible as well.
This could replace state of the art procedures e.g. pulmonary artery band. That we know and are using now.
For this purpose the metallic dilatable stents in common use in cardiology practice can be prepared to hold the balloon inside it. The balloon material that can be used is similar to the one used in valvotomy balloons in our current practice, however the essential requirement is only inflatability and non reactivity.
As this procedure is expected to be done in the catheterization laboratory, I believe it would be executed with much less mortality, morbidity and expense as compared to its surgical counterpart. I expect it thus to revolutionize the practice. Because the ability to perform a per catheter band without mortality will definitely make surgical corrections of simple as well complicated cardiac lesions not needed or at least deferrable to the time where they could be done with less mortality. If we combine this by the ability to control the pressure gradient during insertion (e.g. during echo or direct measurement in the cath and ascertaining the homodynamic consequences directly).
the ability to reduce or increase the pressure gradient at the same setting or at
later settings. For more complex lesion, it can be done as a permanent
palliation or in preparation for future palliation.
I suggest the name of Lotfy's stent for the stent that will be designed for this
The previous state of the art:
To achieve control over the blood flow inside the vessels a surgical procedure is undertaken (with its inherent costs, risks) to band the vessel from outside. Different systems had been devised for this but they were all applied from outside the vessel.
Problems in the previous slate of the art:
1. High cost of the surgor\•, with inhevenl risks ;iml problems associated with
the throrncic surgeries.
2. Sometimes the condition of the patient (e.g. a sick baby) is not suitable for
the operation despite its urgency.
3. The inability to change the degree of the band once the operation is over
except with another operation with again higher risks.
4. Fibrosis and distortion produced during and after the surgery would make
future operations in the area involved more difficult.
What is new_abo_ut_the inyeriHan ?
1. Achieve the same lesull ,is the ,surgical intervention.
2. Avoid the risk and complications of surgery and reoperalion.
3. The ability lo change ihe degree of narrowing produced during and after
the catheter procedure.
The procedure of pulmonary' artery Kind ing and related procedures was never reported in ihe literature lo be done intravascularly.
How can it be used^?
A selected company producing the common use intravascuiar stent will be chosen after agreement with the inventor to upgrade some of its stenls with Ibe new designs and linings 1 suggested.
1. A flow control device  comprising :
a stent  to be placed inside a vessel; and
- a lining  made of non-reactive material fixed inside said stent,
characterized in that said lining is inflatable and deflatable to control the
2. A device  as claimed in claim 1, wherein the stent  is at least one of the
made of metallic material;
- made of plastic material;
- totally inflatable
shaped as a ring
- of tubular shape
- of cylindrical shape
of conical shape
- of pentagonal shape.
3. A device  as claimed in claim lor 2, wherein the lining  is made of
4. A device  as claimed in claim 1,2 or 3 , wherein the stent  is adapted to
be placed inside:
a blood vessel, airways,
- urinary passages, gastrointestinal passages and industrial pipes.
|Indian Patent Application Number||1516/DELNP/2006|
|PG Journal Number||24/2011|
|Date of Filing||21-Mar-2006|
|Name of Patentee||LOTFY WAEL MOHAMED NABIL|
|Applicant Address||43 GIZA STREET, CARIO 12211, EGYPT|
|PCT International Classification Number||A61F 2/06|
|PCT International Application Number||PCT/EG2003/000009|
|PCT International Filing date||2003-11-22|