Carotid endarterectomy is an operation to remove an atheromatous narrowing of the internal carotid artery. This removes the source of embolism and reduces the risk of future stroke.
Carotid angioplasty and stent – one can use a balloon inserted via an artery to stretch the narrowed artery. A stent can be inserted to keep the artery open. Although less invasive this technique is not safer than carotid endarterecomy and has not yet been shown to reduce the risk of future stroke (see image below). Randomised trials to establish its effectiveness are in progress.
Diagram to show the principal of angioplasty: (i) the carotid bifurcation with severe atherothrombotic stenosis; (ii) the guidewire (small short arrow) with the deflated (short thick arrow) balloon catheter (long arrows) is passed across the stenosis; (iii) the balloon is inflated and the plaque is pushed outwards, so stretching the arterial wall and cracking the plaque; (iv) after the balloon is deflated and removed, the lumen has been widened, the arterial wall remains stretched and the plaque remains.
Catheter angiogram before (a) and after (b) stenting; before stenting there is a severe stenosis of the internal carotid artery (arrow) and afterwards the mesh of the stainless steel stent can be seen spanning the carotid bifurcation (modern stents are not so easily seen). (Courtesy of Prof Martin Brown, London)