ABSTRACT
Directional coronary atherectomy (DCA) ablates plaque by cutting and physically removing the plaque material from the coronary artery. A rotating cutting blade (approximately 2000 rpm) within the distal cutting window section of the catheter is advanced across the window and cuts or shears the plaque by rotating the cutting edge. A chamber to house the resected material is contained within the catheter distal to the window (Figure 10.1). To ablate and retrieve an atherosclerotic obstruction, the device is advanced over the wire to the lesion and multiple passes are made, cutting the material and storing it in the catheter housing. A low-pressure balloon is inflated at the lesion location to press the open cutting area towards the wall of the vessel where the plaque is being ablated. Balloon deflation allows circumferential rotation of the entire catheter to orient the cutting window towards the remaining obstruction. The catheter must be removed from the body to retrieve the plaque debris. Reinsertion of the catheter and repetitive atherectomy are performed until the angiographic or intravascular ultrasound (IVUS) appearance is acceptable. The net impact on the lesion of the catheter is a combination of dottering, cutting, and balloon angioplasty (Figures 10.2-10.4).
