Coronary atherectomy is a catheter-based procedure used to treat coronary artery disease (CAD), a chronic disease characterized by the “hardening” (atherosclerosis) of the coronary arteries. During an atherectomy, a physician guides a long, thin tube called a catheter into the blocked coronary arteries. This catheter has been equipped with special devices that remove some of the fatty plaque inside the blocked arteries.
An atherectomy may be performed before other catheter-based techniques, such as balloon angioplasty and/or stenting. However, as angioplasty and stent technology steadily improve, the use of coronary atherectomy is declining. Currently, atherectomy is used in only about 3 percent of patients undergoing coronary intervention. Its use is usually reserved for patients who have very hard or heavily calcified plaque, or who have unusual lesions inside their coronary arteries.
An atherectomy is performed in a catheterization laboratory. As with balloon angioplasty and other catheter procedures, patients are numbed with a local anesthetic at the site where the physician will insert the catheter. This is usually the groin area, although physicians sometimes use the wrist or arm.
After inserting the catheter, the physician guides it up a blood vessel to the heart. Once the catheter is in place, the physician cuts away plaque using either a sharp blade or a rotating device (such as a burr) attached to the tip of the catheter.
Following the procedure, the catheter is removed and the patient is allowed to recover. Most patients can go home after about 24 hours.
About coronary atherectomy
Coronary atherectomy was introduced in 1993 as a way to treat patients with advanced coronary artery disease (CAD). It may be performed in conjunction with other catheter-based procedures such as balloon angioplasty and stenting.
However, the use of coronary atherectomy is declining as newer angioplasty and stent technologies improve their success rate. Today, coronary atherectomy is performed in only about 3 percent of patients who need coronary intervention. Its use is generally reserved for patients with hard, calcified plaque or unusual lesions in their arteries. In general, studies show that coronary atherectomy does not have better outcomes than the much more common balloon angioplasty, and in some cases may have worse outcomes. As a result, these procedures are generally reserved for specialized situations.
Patients who may be referred for coronary atherectomy include:
Elderly patients
Patients with calcified plaque that is not suitable for conventional angioplasty
Patients with unusually large plaque deposits
Patients who have undergone angioplasty and stenting but are still experiencing vessel closure
Patients with chronic total coronary artery occlusion, a disease characterized by severe and ongoing blockage of the coronary arteries
Patients who are unable to undergo any catheter-based procedure may be recommended for coronary artery bypass surgery, a form of open-heart surgery.
Although patients with CAD may live for years without needing either surgery or a catheter-based procedure, intervention becomes necessary when clogged arteries limit the amount of oxygen-rich blood reaching either the heart or the organs/tissues of the body.
Catheter-based treatments are measured, in part, by the restenosis rate, or how often the coronary vessel re-closes after the treatment. The most common catheter-based treatments used to treat CAD are balloon angioplasty and/or stenting. During a balloon angioplasty, the physician guides a catheter tipped with a balloon into the blocked artery. The balloon is inflated, crushing the plaque against the artery wall and restoring blood flow to the heart muscle. A stent, or very thin metal tube, may be implanted in the artery to help keep it open. Stents dramatically improve the restenosis rate of balloon angioplasty. Newer drug-eluting stents have dramatically improved the restenosis rate.
Types of coronary atherectomy
There are three forms of coronary atherectomy:
During a directional coronary atherectomy (DCA), the catheter tip is equipped with a bladed device that cuts away the plaque and stores the pieces in a tiny container. The DCA device is designed to remove “soft,” or noncalcified, plaque. It has an encased cutting blade that is pressed against the plaque by the inflation of a balloon on the opposite side of the catheter. Multiple “cuts” are performed. After each “cut” into the plaque, the balloon is deflated, the catheter is turned 30 to 60 degrees, and the balloon is re-inflated so the next cut can be made. The pieces of plaque are collected within the device for removal.
During a rotational atherectomy, the physician uses a rotablator equipped with a “burr” at the tip. The rotablator is inserted into the coronary artery where the blockage is located. Once activated, the burr rotates as fast as 200,000 revolutions per minute, allowing the physician to drill through the arterial blockage, grinding the plaque into very small particles. In most cases, these microparticles can travel safely through the circulatory system. This technique is useful for harder, calcified plaque. It is the most common kind of atherectomy.
During a transluminal extraction, the physician uses a transluminal extraction catheter (TEC) equipped with tiny rotating blades and a hollow tube. As plaque is cut away from the artery wall, it is sucked into the tube by a vacuum and expelled from the body. This technique is useful for blockages containing blood clots.
Another form of transluminal extraction can be performed with a device known as an Angiojet. Like the TEC device, the Angiojet is a sucking/vacuum device. Rather than cutting away the plaque and blood clots, the Angiojet dislodges them with a high-velocity stream of saline solution that is directed back into the catheter, dragging the debris with it.
These two devices are of particular use in previously placed bypass grafts that are larger than natural coronary arteries. These bypass grafts often have debris from plaque and blood clots that might otherwise be showered downstream into the relieving vessel if angioplasty and/or stenting are done alone.
During coronary atherectomy
The experience of an atherectomy is very similar to other catheter-based procedures. Prior to an atherectomy, a physician will review the patient’s medical history, including all over-the-counter or prescription medications being taken.
Certain medications may need to be stopped or reduced. Patients with diabetes are encouraged to talk to their physicians about food and insulin intake. Patients are usually asked to stop eating and drinking 12 hours before the procedure.
On the day of the procedure, the patient is taken to a sterile cardiac catheterization laboratory that may resemble an operating room. There will be many monitoring devices, video display equipment and x-ray cameras. A nurse or physician will explain what will occur, and the patient is encouraged to ask any questions.
Once the patient is made comfortable, the physician inserts an intravenous (I.V.) line into the arm, usually at the back of the wrist. The I.V. allows the physician to administer sedatives and other necessary medications, including anti-platelet medications . Heart rate and blood pressure devices will be taped to the patient’s body for on-going monitoring.
The physician usually uses the groin/upper thigh area to insert the catheter into the body, but some physicians may choose the arm or wrist instead. Whatever area is chosen, it will be cleaned, shaved and numbed with a local anesthetic. The catheter is then passed through the blood vessel (e.g., the femoral artery in the groin/upper thigh) and up into the heart. There may be some minor discomfort as it moves up the blood vessel.
Once the catheter is in place, an x-ray of the left ventricle (left ventricular angiogram) and the coronary arteries (coronary angiogram) will be taken. The angiogram helps the physician to see exactly where the blockage or narrowing is located.
The patient may feel hot or flushed for about 30 seconds as a special dye (contrast medium) is injected through the catheter and into the left ventricle. Contrast is also injected into the coronary arteries, although there is generally no sensation associated with these injections.
Once the angiogram has been reviewed, a plan for treating the blockage (usually immediately) is made by the physician. Depending on the blockage, the physician will choose the appropriate device or devices for plaque removal. These devices may include atherectomy catheters and/or balloon angioplasty catheters and stents.
The most common atherectomy-related device is the rotablator device, which uses a tiny burr to grind the plaque away. During this procedure, the patient will hear a high-pitched sound and may experience chest discomfort when the rotablator is activated. Drilling through a large blockage may be done slowly to avoid complications. It is routine to use a temporary pacemaker during rotablator procedures, because the micro-particles released during the drilling may slow the heart rate.
After the atherectomy has removed (debulked) some of the plaque, a balloon angioplasty and/or stenting may be performed. During the stenting, the physician may choose to use a drug-eluting stent instead of a “bare metal” stent. Drug-eluting stents have been coated with special drugs that help prevent restenosis, or the re-closure of the artery.
Restenosis can occur after an atherectomy, angioplasty or stenting procedure. If it does, another procedure may be necessary, or if the arterial blockage is more severe, the physician may recommend coronary artery bypass graft (CABG).
Once the treatment is finished, final pictures are taken and the catheters are removed, completing the procedure.
After coronary atherectomy
Once the procedures are completed, the patient will be transferred to a cardiac recovery room. The individual may feel groggy from the sedative. The catheter insertion site may be bruised and sore.
If the groin area was used as the point of catheter insertion, the patient will be instructed to lie in bed with the legs out straight. The physician may choose to use one of two techniques for removing the sheath that was placed at the initiation of the procedure. The traditional technique is to wait until the effects of the anticoagulant have passed (four to six hours) and then apply pressure while removing the sheath. A newly developed technique allows the sheath to be removed immediately after the procedure through the use of hemostatic devices that seal or stitch the femoral artery.
If the wrist or arm was used as the point of catheter insertion, the patient does not need to stay in bed. Throughout the post-procedure monitoring, the point of catheter entrance will be checked for bleeding, swelling or inflammation. Vital signs will be continuously monitored. It is highly recommended that patients drink fluids during this rest period. Usually, the patient will stay overnight for further observation.
Patients are typically discharged after 24 hours. They usually leave with instructions from their physician regarding:
Exercise and exertion. Patients are asked to limit their physical activity (e.g., avoiding aerobic exercise) for 24 to 48 hours. They are also advised against driving for approximately one week to allow the puncture site to heal properly.
Care of the incision area. People can shower normally because there is no bandage over the incision area. Numbness or soreness is possible and normal during the first week, and any bruising may take as long as three weeks to heal. Undue pain or swelling may require additional medical attention.
The function and use of medications. This is often a good opportunity to review with the physician issues of primary prevention of coronary artery disease, risk of recurrence and medical follow-up plans.
Generally, relaxation is the key to post-procedural recovery. Gradually returning to normal activities, beginning with the least stressful and working toward a routine daily schedule, speeds healing and reduces the risk of complications.
Potential risks of coronary atherectom
The chance of serious complications during an atherectomy is quite small, but slightly higher than that of other catheter-based procedures, such as a balloon angioplasty. Serious complications that may arise include:
Abrupt closure vessel
The need for emergency bypass surgery
Heart attack
Less serious complications include an inability to move the catheter into the target location, blockage caused by loose particles of plaque or perforation of a blood vessel.
Restenosis, or re-closure of the artery, is also a possibility. Physicians will usually recommend follow-up coronary angiograms to make sure the vessel stays open after an atherectomy.
About peripheral atherectomy
Although coronary atherectomy refers only to a procedure performed in the coronary arteries, an atherectomy can be performed to remove plaque in other blood vessels.
For example, the peripheral arteries (leading to the arms and legs) are highly susceptible to plaque and calcification. In this case, a special type of atherectomy called a peripheral atherectomy may be recommended. In this procedure, directional coronary atherectomy is typically performed to disintegrate the plaque, which is then flushed through the bloodstream. A balloon angioplasty and/or stenting procedure may also be performed.
Questions for your doctor about atherectomy
Preparing questions in advance can help patients have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions about atherectomy:
Why do I need an atherectomy?
Why do you recommend this procedure over alternative treatment?
What are the risks and benefits of atherectomy?
What type of atherectomy will be performed?
Where will I receive the procedure?
Do I have any restrictions prior to the procedure?
How long will the procedure take?
What is the recovery period from this procedure?
What are the chances that my vessels will close again?
Will I need additional treatment after the atherectomy?
