What Is Atherectomy?

Overview

Atherectomy is a key surgical procedure in cardiovascular health used to ease symptoms of coronary artery disease (CAD) and peripheral artery disease (PAD), essentially aiming to restore normal blood flow. CAD is a consequence of cholesterol and calcium based- plaque buildup in arteries supplying your heart, known as atherosclerosis. It should be emphasised that the plaques are composed of high calcium levels and are not influenced by diet or supplements. The cause of arterial plaques is deliberated over, but increasing research suggests that it is due to aging of arterial muscle cells. Whereas, PAD refers to plaque buildup in the arteries in your limbs.¹ PAD is more prevalent in African Americans, and risk is increased by smoking, chronic high blood pressure, diabetes and being over the age of 60.² In 2018, 12,264 people assigned as men at birth and women at birth of all ages in the United States passed away due to PAD, with the highest risk factor being smoking.³ 

Atherectomy requires a unidirectional or rotating blade inserted into the arteries by a catheter and guidewire, which is preferred as it is less invasive than its counterpart endarterectomy. Endarterectomy involves incision of the artery to remove the plaque. Atherectomy may be used as a standalone therapy, or is accompanied by other procedures such as using stents, which are expandable mesh tubes to widen the arteries, or using balloons known as angioplasty. However, this article will primarily focus on atherectomy as a sole treatment. 

Types of Atherectomy Procedures

Patient selection

You will be selected as a candidate for this procedure if you:⁵

• have lesions (damage to tissue) that are severely calcified
• a guidewire is able to move across the lesion
• are an adult

Contraindications

You will not be offered this treatment if:⁵

• you are pregnant
• an angiography, a special X-ray to view blood vessels, shows you have a blood clot
• the lesion is inside an existing stent
• the vessel is at increased risk of damage
• the lesion is in your right coronary artery or left circumflex arteries
• the amount your heart pumps with each heartbeat is less than 25%¹⁴

Clinical Outcomes and Success Rates

The United Kingdom has the highest rate of use of rotational atherectomy in Europe as of 2021.⁸ However, this is still very low at 2-3% compared to balloon angioplasty, which is used as a first-line treatment. No major clinical trials are looking at atherectomy as an individual treatment and its long-term effects, so we will look at atherectomy as a treatment to prepare for angioplasty or stenting. A review article comparing seven randomised clinical trials showed insufficient evidence to be confident about the effectiveness of atherectomy for PAD over traditional angioplasty use.⁹ This is not solely due to it being of similar effectiveness to angioplasty, but also due to the lack of training which results in low confidence in using this procedure. It should be noted that atherectomy is most useful for calcified lesions that cannot be dilated using angioplasty alone.¹⁰ On the other hand, clinical outcomes of atherectomy for CAD are more promising, as highlighted by the ORBIT II trial, which showed that fewer events caused by reduced blood flow happened after orbital atherectomy when paired with stent placement.¹¹ There were also major cost benefits as there were fewer readmissions for bypass surgeries and shorter hospital stays.¹¹ This trial’s findings were so clinically significant that it was pivotal for the approval of the first orbital atherectomy device by the Food and Drug Administration in 2013.

Patient Preparation

An angiography is done pre-procedure to assess the extent of the narrowing of the arteries.¹ This is usually paired with an intravascular ultrasound to monitor blood flow, thus identifying blockages.¹² The ultrasounds are far more effective in identifying calcified lesions as compared to X-rays by around 40%.¹³ X-rays often underestimate the severity of the calcification but are still the gold standard of practice, highlighting that protocol improvement is needed to offer atherectomy earlier to patients.¹³ You may be asked to refrain from using blood-thinning drugs to reduce the risk of bleeding and stop consuming food a few hours earlier. It is performed under local anaesthesia, and the guidewire to which the tool is attached to is threaded into a vessel below the groin.

Post-Atherectomy Care

You are required to lay flat for a minimum of 6 hours to reduce the risk of bleeding after the procedure.¹ During this time, the healthcare team will monitor your vitals, such as blood pressure, and you are usually allowed to return to normal activities the next day.¹ Intraprocedural steps such as using saline and lubricants are used to reduce thermal injury and blockages, but there may be complications if the wrong blade size is used or if rest periods between series of cuts are not adequate.¹⁴ These result in damage known as vessel dissection, after which the procedure should only be reattempted after a month to allow healing.^5,14

The possible complications are:^5,15

• Bleeding
• Infection
• Bruising
• Very rarely, a piece of the plaque may not be removed and lodged into another part of the vessel
• Dissection

Advancements and Innovations

Emerging technologies in atherectomy include pairing this technique with novel angioplasty. This involves using a balloon with a slow-release drug coating to increase the success of atherectomy, as plaques tend to come back, especially in vessels below the groin.¹⁶ The limitation of this treatment is that there is insufficient diffusion of the drug across the severely calcified lesions, so it may only be effective for selected cases.¹⁷ Moreover, robotics such as the CorPath GRX robotic system have been found to be useful for non-complicated lesions, but more improvements in design are needed.¹⁸ The major drawback to this current technology is that the initial vascular access still has to be completed by your surgeon. However, this being said, it allows for manual adjustments of the robotic system if it fails. Another limitation is that when the joystick is used to retract the robotic arm, it can damage the ultrasound catheter. Therefore, it is important to integrate these robotic devices with imaging modalities. To date, only atherectomy devices are integrated with imaging for PAD but not CAD.¹⁹ This device has been shown to remove a sufficient proportion of the plaque whilst saving most of the vessel’s connective tissue and thus retaining its mechanical strength.²⁰

Summary

Atherectomy is a minimally invasive surgical procedure used to reduce plaque size in your vessels or prepare your vessels for additional treatments to widen them and improve your cardiovascular health. It is clear that there is a lot of potential for atherectomy to become a first-line treatment if practitioners are given more training and if it is integrated with imaging technology to increase confidence in robotics-powered procedures. A recent example of a successful atherectomy is a patient at the Royal Papworth Hospital, renowned for lung and heart treatment, who was the first to be offered to have their stent cleaned of plaque buildup using Excimer laser coronary atherectomy, which prevented him from having a bypass and prolonged the life of his previous stent.²¹ This shows that you may be able to benefit from atherectomy for the initial removal of your plaque, preparing arteries for stenting, or even in the follow-up to enhance the efficacy of previous treatments. Rotational and orbital atherectomy are most commonly used, but not many studies compare them. One study conducted between 2014 and 2018 with over 1,000 patients showed that both methods are effective, and there is not much difference in major adverse cardiovascular and cerebrovascular events, such as mortality or strokes.²² Therefore, future directions should include more comparative studies to establish the best atherectomy technique for different lesions ranked by their calcification and improve robotic imaging devices that allow intra-procedure and post-procedure evaluation of the plaque. 

FAQs

Am I a candidate for atherectomy?

You will be considered for this procedure if pre-procedural imaging tests show that your plaque is severely calcified and your vessels will withstand this procedure without rupturing.

Can I return to my normal activities the next day?

The procedure lasts around 2 hours, you are required to lay flat for a minimum of 6 hours and can return to low-impact activities the next day.

Can I eat or drink before the procedure?

You can eat and drink before your procedure, but your clinician may advise you to stop consuming food a few hours beforehand. As this is a minimally invasive technique, you will be put under local anaesthesia, and the risk of nausea is low.

Is it true that I may experience constipation after the surgery?

It is common to experience constipation after most surgeries due to a combination of factors, such as anaesthesia, painkillers, low mobility and lack of appetite. You are advised to eat normally and consume hot drinks to help with your bowel movement.