What is Elana
ELANA is an acronym that stands for: Excimer Laser Assisted Non-occlusive Anastomosis.
Professor Cornelis Tulleken from the University Medical Centre (UMC) in Utrecht, The Netherlands, is the developer of this bypass procedure, which has been in use in Europe for 17 years.
The bypass procedure uses the graft to connect the two ends of an artery. Connecting the graft to the artery is called an “anastomosis” (from the Greek word to join together “without leaving a mouth” or opening) There are two ways to perform an anastomosis: (A) conventional and (B) ELANA
A. Conventional anastomosis
During the conventional anastomosis, the vessels are connected to each other by temporarily closing the diseased artery. The diseased (recipient) artery is clamped-off during the procedure to prevent blood flow. Once blood flow is stopped in the recipient artery, a thin knife is used to open a slit along the side of it (called an arteriotomy). After the slit is made, the harvested graft vessel (usually from the lower leg) is stitched onto the edges of the opening. Once all the stitches have been placed around the slit (to hold the ends of the blood vessels together), then the clamp is released to allow blood to flow again into the recipient vessel, and the bypass is complete.
B. The ELANA procedure
The procedure usingELANA, is only one part of the anastomosis surgery and is a method for connecting the bypass graft to the artery in your brain. This step generally takes over one hour and may take two or more hours in exceptionally difficult situations. In contrast to the conventional technique where the recipient artery is first closed and then connected to the harvested vessel from the leg, ELANA makes it possible to connect vessels without closing the recipient artery. With the ELANA procedure, instead of a slit being made with a knife, a hole is burned into the recipient vessels after stitching the harvested graft vessel (from the leg) to the diseased vessel. This method avoids the use of an occluding clamp, and it allows the flow of blood in the diseased vessel to continue during the suturing procedure. Avoidance of vessel occlusion during the procedure keeps the brain supplied with oxygen-rich blood during the suturing process, avoiding potential ischemic stroke damage.
The following surgical steps are taken:
The surgeon selects appropriate locations on the artery to connect the bypass, one before and one behind the diseased vessel segment (aneurysm or tumor). A suitable donor graft is prepared; it is usually taken from the patient’s leg.
1) An ELANA platinum ring is connected to the end of the donor graft with sutures (A, B, C).
2) The graft with ring is attached to the artery wall with sutures (D).
3) The laser catheter (E) is inserted in the open end of the donor graft, and vacuum suction is applied to assure a good contact between the laser catheter tip and the artery wall. Laser pulses are applied, and a circular hole is burned into the vessel wall.
4)The laser catheter is gently pulled back from the graft (F). By continuing the vacuum suction, the circular tissue cut remains fixed to the tip of the catheter. Blood flow through the graft is an indication of a successful arteriotomy procedure.
5) If required, the bypass can be made in this way at both ends. In this case, there is no conventional connection, and the ELANA procedure is performed twice
After the bypass is made, complementary treatments can be used to treat the diseased part of the vessel. If the diseased part of the vessel is an aneurysm, it can be clipped, or removed.
Potential Benefits of ELANA
There are several advantages to make a bypass using the ELANA Technique.
During surgery, the less the brain is jostled or moved, the better the recovery for the patient. ELANA allows your surgeon to treat the diseased blood vessels without excessive manipulation of delicate brain tissue. With ELANA, the surgeon requires a little bit less operating space.
Before the advent of the ELANA Technique, the conventional procedure of performing a bypass required a period of temporary closure of the diseased artery. This temporary vessel occlusion allowed the surgeon to make a small slit in the side of the artery (i.e., arteriotomy), so that the bypass graft could be stitched onto the edges of the opening. Temporary occlusion times between 30 to 60 minutes were required to perform the bypass stitching. This prolonged occlusion time increased the risk of reduced oxygen concentration in the brain, thus increasing the risk for stroke damage.
A significant portion of the complications associated with the conventional bypass operation is thought to be related to the temporary occlusion time. During the occlusion time required with the conventional bypass, a significant section of the brain may be left without sufficient blood flow. This reduction in blood flow and oxygen delivery can result in a stroke or brain injury. When a brain area is not being supplied with necessary oxygen-rich blood, the condition produced is called ischemia. It is this “ischemic time” that may be significantly reduced or eliminated by using ELANA. By eliminating this risk, potential complications associated with bypass surgery may be significantly reduced.
Possible risks of ELANA
All of the possible complications of ELANA are not yet fully known. However, it is believed that the potential risks would be similar to those of standard bypass procedures that are currently in use. The following is a list of potential risks that may be associated with the ELANA, as well as the potential risks of the artery bypass procedure in general. Those specifically associated with ELANA are noted as such.
Risks of bypass procedures in general
- A blood clot (embolus) may result in brain injury, stroke, or pulmonary embolism.
- A hole or tear at a suture site, in the bypass, in an adjacent artery, or in the aneurysm or pseudo-aneurysm may cause bleeding. This hemorrhagic event may lead to brain injury, may require surgery to repair the hole or tear, and may even cause death.
- Bypass deformity, kinking, or thrombosis (clot formation) may require additional surgery and may result in brain injury, bleeding, stroke, and can cause death.
- Pushing and holding the brain aside in order to perform the bypass may result in temporary or permanent damage. Injection of contrast dye for angiograms may cause an allergic reaction which may produce side effects.
- Incomplete closure of the aneurysm, removal of tumor, or failure to establish a working bypass may require additional treatment or surgery.
- Narrowing of arteries or bypass graft during procedures may require additional surgical repair and prolong surgery.
- Temporary narrowing (spasm) of the graft or arteries may reduce blood supply to the brain, which may result in stroke and can cause death.
- Surgery, anesthesia, or angiography may cause complications includinghydrocephalus (“water on the brain”), emboli (blood clots), bleeding, perforation, allergic reactions, mechanical damage, respiratory failure, or infections, all of which could be fatal or cause permanent damage.
- Drawing blood for tests may result in slight bruising, pain, and may cause infection.
- Reduced kidney capacity or kidney failure may require medication or lead to chronic (long-term) dialysis.
- Temporary occlusion of the artery may result in brain injury or ischemic stroke.
- The aneurysm can start to bleed after the bypass has been made, flow to the aneurysm has not yet been completely stopped, which may lead to brain injury and can lead to death.
Risks specifically associated with ELANA
- The use of the ELANA or its accessories may damage arteries or the bypass itself and also may cause bleeding, occlusion (blockage of the artery) or clot formation. These conditions may cause stroke leading to other complications and death.
- Incorrect positioning or imperfect cutting of the ELANA System may cause bleeding or thrombosis (clot formation) and may require further surgery and may cause death.
- A longer surgery time with the ELANA System may increase the risk offailure of one or more organs.
- Contact with parts of the Elana system or its accessories may cause allergic reactions