Atherectomy is an endovascular procedure used to remove or ablate atherosclerotic plaque from the walls of blood vessels, typically arteries. It's employed when standard angioplasty might not be effective due to the nature of the plaque, such as when it's heavily calcified or when there's a high risk of complications from stenting. Here are the details on techniques and indications:
Techniques of Atherectomy:
Directional Atherectomy:
Uses a catheter with a small, rotating blade at the tip to shave off plaque. The debris is collected in a chamber on the catheter and removed from the body.
Particularly useful for lesions where the plaque is located on one side of the vessel.
Rotational Atherectomy:
Involves a high-speed rotating burr (diamond-tipped) that sands down calcified plaque into microscopic particles small enough to pass through the capillaries and be cleared by the body.
Effective for severely calcified lesions in coronary or peripheral arteries.
Orbital Atherectomy:
Utilizes a diamond-coated crown that orbits within the vessel, pulverizing plaque into tiny particles. This method can treat both hard and soft plaque.
Offers the advantage of treating lesions of various sizes without changing tools.
Laser Atherectomy:
Employs laser energy to vaporize or ablate plaque. It can be particularly useful for treating in-stent restenosis or when conventional methods are not feasible.
The laser can also be used to cross chronic total occlusions.
Excisional Atherectomy:
Similar to directional atherectomy but involves cutting away larger pieces of plaque which are then captured and removed.
Indications for Atherectomy:
Severely Calcified Lesions: When plaques are too hard for balloon angioplasty alone to be effective.
In-Stent Restenosis: When there's re-narrowing of an artery previously treated with a stent, and repeated stenting is not advisable.
Chronic Total Occlusions (CTOs): When arteries are completely blocked for a long period, and standard crossing techniques fail.
Peripheral Artery Disease (PAD): Especially in the lower limbs where calcification is common, to improve blood flow and reduce symptoms like claudication or to prevent limb loss in critical ischemia.
Lesions at Bifurcations: Where directional plaque removal is needed to preserve the opening to side branches.
Lesions with Heavy Thrombus Burden: Where removing the thrombus might reduce the risk of distal embolization or improve outcomes in acute settings.
Patients at High Risk for Stenting: Including those with a high likelihood of restenosis, bleeding risks, or those who might not tolerate prolonged dual antiplatelet therapy.
Atherectomy is often used as part of a broader treatment strategy, possibly in conjunction with angioplasty and stenting, to prepare the vessel for optimal outcomes. The choice of technique depends on the specific characteristics of the lesion, the patient's overall health, and the expertise of the interventionalist.