Directional coronary atherectomy (DCA) is an important advance in the mechanical revascularization of stenotic coronary arteries. The bulky nature of the DCA device has necessitated the use of guiding catheter designs that are more cumbersome to use than balloon angioplasty guiding catheters. Because engagement of coronary artery ostia with the currently available DCA guiding catheters is often difficult and because DCA guiding catheters significantly "relax" and reshape during the atherectomy procedure, angiography using these guiding catheters before and after atherectomy can be suboptimal. A new technique for angiography during atherectomy using long Judkin's diagnostic catheters inserted through the existing DCA guiding catheters is described. This technique can be used for optimal visualization of the coronary arteries with minimal use of contrast before and after sessions of atherectomy and also can be used to help engage the DCA guiding catheters. Some improvements in the design of guiding catheters for DCA are suggested.