Atherectomy is a minimally invasive procedure which removes some of the deposits in the artery wall that are responsible for blockages (plaque). Plaque is a build up of fat, cholesterol and other substances that narrow and harden a blood vessel.
Unlike angioplasty and stents, atherectomy involves removing the plaque from the vessel. This is done by either using a tiny rotating blade. These techniques can be used to remove some of the bulk of the disease, and angioplasty and stents can also be used after atherectomy to improve success.
By removing plaques, atherectomy intends to improve the short and long term benefits of angioplasty and stenting, reduce the need for surgical wounds (and so reduce the healing time).
The procedure is considered less invasive than Endarterectomy, which involves open surgery and removing plaque from the inner wall of a diseased vessel.
The advantages of atherectomy when compared to endarterectomy are; faster procedure time, ease of use, quicker recovery, reduced complications from open surgery and that it can be repeated in the future. It is also advantageous for patients not fit for surgery.
Laser angioplasty is similar to balloon angioplasty, but instead of a balloon-tipped catheter, a catheter with a laser tip is used. The laser is guided to the blockage which then destroys the plaque, vaporizing it into gaseous particles and re-establishing a channel for blood to flow in.
The laser can be used alone, or in combination with balloon angioplasty and/or stenting.
Another technique that has been used to try to overcome the problems with simple balloon angioplasty is to use a balloon that is inflated with very cold gas. The concept is that if the tissues are cooled by such a technique, that the amount of damage to the artery is limited, and that this may cause less problems with re-narrowing in time. At the time of writing, there is no study data to indicate that this is so; however these devices have been used from time to time, when angioplasty or stenting have not worked sufficiently.
Drug eluting balloons
One of the problems with angioplasty and stenting, particularly in some areas (such as the leg arteries below the groins), is that the disease has a tendency to recur and the arteries to re-narrow. In an attempt to reduce the likelihood of this happening some special angioplasty balloons have been developed which are coated with a special drug. When the balloon is inflated inside the diseased area of the artery, the drug is forced into the artery wall, with the intention of reducing the chance of recurrence of the narrowing.
At present these balloons are undergoing clinical studies to test if the theoretical benefits that they may give do deliver an improved outcome for patients.
A cutting balloon is an angioplasty device that has a special balloon with small blades or wires that are activated when the balloon is inflated. When the balloon is inflated the blades or wires are pushed into the wall of the artery, causing a very small cut in the wall. This allows the disease, which is causing narrowing, to be released. The potential benefits for using such devices are two:
- Firstly the balloon pressure required to perform the angioplasty are reduced, which may in turn make the procedure less uncomfortable (in some situations).
- Secondly the small cut, or score, allows the channel in the artery to be reformed, but at a lower balloon pressure. The theory being that with less pressure there will be less stimulus to the process of re-narrowing.
The precise role that cutting balloons may play in treatment of vascular diseases remains to be determined by clinical studies.