Coronary Atherectomy - Advantages, Disadvantages, and Procedure

Introduction:

Coronary atherectomy is used to treat severely calcified and resistant coronary lesions (plaque) that would not respond to a typical percutaneous transluminal coronary angioplasty (artery repair). Plaque is the accumulation of cholesterol, fat, calcium, and other chemicals in the arteries. It can either restrict blood flow or burst, resulting in blood clots. This plaque buildup is known as atherosclerosis. An atherectomy is a procedure used to treat atherosclerosis. Orbital atherectomy, cutting balloon angioplasty, and percutaneous transluminal rotational atherectomy are the main methods utilized in plaque ablation (obstruction removal). Treatment for thrombus-infected grafts or severely angulated arteries should not employ this method.

What Are the Different Kinds of Coronary Atherectomy?

The following are the many forms of coronary atherectomy:

• Excisional Atherectomy: A blade is used to cut plaque in only one direction.

• Atherectomy Using Laser Ablation: A laser device is used to remove plaque.

• Orbital Atherectomy: It is used to remove plaque with a rotating instrument that works like sandpaper.

• Rotational Atherectomy: It involves the use of tiny blades to cut plaque in a circular motion.

What Are the Advantages of Coronary Atherectomy?

• Coronary lesions that cannot be crossed with balloon catheters or cannot be dilated at pressures even higher than 20 atm. Such lesions can be effectively treated with coronary atherectomy.

• It enables successful balloon dilatation and stent implantation.

• It is also recommended for treating minor calcified lesions in order to change the vessel's compliance and enable balloon angioplasty.

• It is also used for extremely calcified coronary lesions with significant calcification visible during fluoroscopy covering both sides of the artery wall for at least 15 mm or those with at least a 270-degree arc of calcium seen on intravascular ultrasound (IVUS).

• It is also effective for complete occlusions, lengthy, moderately calcified lesions, as well as saphenous vein graft lesions.

• Because of plaque shift and high rates of restenosis (obstruction of arteries), bifurcation lesions are particularly difficult to treat with traditional balloon angioplasty.

What Are the Disadvantages of Coronary Atherectomy?

• When a thrombus burden is present, atherectomy may result in moving the emboli to a distant structure (distant embolization).

• Additionally, thrombi frequently surround unstable or ruptured plaques, which may perforate or dissect when treated with these techniques. It may worsen dissections caused by unsuccessful angioplasty attempts or those that occur spontaneously in the coronary arteries.

• If there is significant curvature, it may be difficult to position the equipment close to the lesion, and the spinning burr may increase the danger of the blood vessel rupturing.

• The lack of cardiac surgery and the patient's ineligibility for coronary artery bypass graft surgery are relative contraindications.

What Equipment Are Required for Coronary Atherectomy?

The Rotablator System - It consists of three components:

1. A console that controls the air supply and monitors the rotation of the burr.

2. A patent foot pedal is used to activate the device.

3. The rotablator is a pre-connected, exchangeable burr and advancing device that houses a driveshaft, air turbine, and burr.

• Orbital Atherectomy System: It consists of a portable instrument and an atherectomy controller.

• The Cutting Balloon Monorail System: It is offered in monorail and over-the-wire forms. Proteins and salt are mixed in a water-based medium that makes up the rotational atherectomy fluid.

What Is the Procedure for Coronary Atherectomy?

First, a local anesthetic is used to numb the groin region. The doctor next inserts a needle into the femoral artery, which flows down the leg. Then a guide wire is put into the needle before removing it. It is then replaced with an introducer, a tubular gadget with two ports used to inject flexible devices into blood vessels, such as catheters. The initial guidewire is replaced with a finer wire after the introducer is in place. This new wire is used to guide a diagnostic catheter, which is a long flexible tube, into the artery. The second wire is then removed.

After injecting the dye and an X-ray with the catheter is taken at the entrance of one of the coronary arteries. If it reveals a curable obstruction, then the first catheter is removed and replaced with a guiding catheter using another guide wire. The wire used for this is then withdrawn and replaced with a finer wire that is advanced over the obstruction. Another lesion-cutting catheter is also advanced over the obstruction location. A low-pressure balloon is inflated near the cutter, exposing the lesion material to the cutter. When a driving unit is activated, the cutter spins. Then the lever on the driving unit is moved, which moves the cutter.

The fragments of obstruction it removes are retained in a portion of the catheter called a nose cone until the process is completed.

Rotating the catheter while inflating and deflating the balloon allows the obstruction to be sliced in any direction, resulting in consistent debulking. A stent may also be inserted. This is a latticed metal scaffold that is placed into the coronary artery to keep it open. Following the operation, the dye is injected again, and an X-ray is taken to examine the arteries for changes. The catheter is then withdrawn, and the surgery is completed.

What Are the Complications of Coronary Atherectomy?

Several unfavorable outcomes are possible when an atherectomy is performed. The complication rate is low if the devices are utilized in well-chosen patients following meticulous preparation.

• Myocardial infarction ( occurs in 1.3 percent of cases).

• Emergency coronary artery bypass surgery (occurs in 2.5 percent of the cases).

• Death (occurs in one percent of cases).

• Dissection (ten percent).

• Coronary dissection after atherectomy (3.3 percent of cases).

• Perforation (1.7 percent of cases).

• Slow-flow (1.2 percent of cases).

• Abrupt artery closure (one percent of cases).

Conclusion:

Coronary atherectomy is a minimally invasive technique that removes blockages from the coronary arteries, allowing more blood to flow to the heart muscle and relieving discomfort caused by obstructions. It has been shown to improve clinical outcomes in individuals with severely calcified coronary arteries by allowing for percutaneous coronary intervention. Despite being used infrequently, its popularity has increased over time. A greater volume of coronary atherectomy has been associated with a lower risk of serious unfavorable outcomes from coronary perforation.