They are endovascular structural prostheses of coronary vessels (coronary stents), placed in a catheter balloon from Germany, that fulfil the ISO 9001 / EN 13485 and CE requirements.

The stent material is stainless steel 316LVM of exceptional quality. The ALIS20 stent uses a unique design for high flexibility which meets the high demands on stenting. The optimized design achieves homogeneous expansion and the reduced elastic recoil leads to a perfect hemodynamic result. All of the above allow it to adapt superbly to the vascular anatomy and provide optimal support.

Prostheses manufactured according to the type ALIS20 have much higher flexibility and material standing time. Furthermore, its ergonomic design ensures easy positioning of the stent on the target lesion and the optimization of the stent geometry provides high stability and the lowest crossing profile. Due to the high permanent stent stability offered by this design, the ALIS20 stent is also ideally suited for implantation in vessels that exert high or irregular radial strength or exhibit extreme tortuosity. Last but not least, the special polishing technique creates a smooth non-thrombogenic stent surface and reduced restenosis. Also, reduced restenosis is achieved by the shortening of the stent which is <2%.

The catheter balloon has a working length of 135 cm. This is a double-lumen fast exchange catheter with a mounted balloon of a semi-compliant Acrylon material and a Hypo-Tube catheter shaft. A proximal and a distal X-ray marker (platinum iridium ring) at the catheter balloon segment define the balloon length (cylindrical part) and allow correct positioning within the stenosis under X-ray control.

Moreover, the balloon material offers high duration (Nominal Inflation Pressure: 6 atm, Rated Burst Inflation Pressure: 16 atm), in order to reach high pressures without bursting, while it eliminates the risk of endothelium dissection or damage.

The typical construction of a catheter appears at the following figure:

The ALIS stents fulfil the latest technical requirements and specifically:

The stent diameter, according to the given pressure appears at the table below:

The expansion rate of the stent increases by 10% for every 1 atm of pressure between the nominal pressure and the burst inflation pressure. The average deflation time is less than 4.07 sec. Nominal pressure is 6 atm and rated burst inflation pressure is 16 atm (in AL0202040 and AL0202440 stents it is 14 atm), while average rated burst inflation pressure is 22 atm.

As an example we refer to the results of a study carried out to compare the biocompatibility of ALIS20 stent to that of other competitive stents. The test objects were applied to the silicon tubes by balloon catheter with an inside diameter of 4 mm. These tubes were integrated to the artificial circulating by connectors.

In the following graph the free haemoglobin is determined during stent application (A=ALIS20 stent, B & C=two other stents and D=without stent).

The following graphs show the Normalized Index of Haemolysis and the Modified Index of Haemolysis in the four aforementioned cases, which were calculated in order to determine the content of haemoglobin and the haematocrit of the blood.

The conclusion is drawn that, under the experimental conditions used, no damages of the blood, caused by the material or constructions occurred, and that ALIS20 stent has very good biocompatibility.

The figure below shows the recoil values for competitive stents and demonstrates the recoil of the ALIS20 stent within normal values. The total recoil for the examined stent at a dilation to 3.5 mm is 2.125%. The recoil value for the stent was examined at four different positions in three different stent regions under an angle of 0° and 90°.

In comparison to competitive stents the next figure demonstrates impressively the high radial stability of 4 mm ALIS20 stents and comparable radial stability to the competitive stents.

The ALIS20 stents are enclosed in a sterile and single-use packaging. They contain user instructions, stent-size sticker labels, the reference and LOT number for easier product tracking.

They are available in the following sizes: