Effects of argon laser on variable grades of atherosclerosis in the human aorta Available to Purchase

Laser vaporization of coronary artery plague and peripheral arterial lesions has been documented in scattered clinical and cadaver studies, but the nature of atherosclerosis present in these studies was not fully documented. This paper reviews work done in cadaver specimens of infrarenal aorta to document the response of atherosclerotic peripheral vascular lesions of variable severity to application of argon laser light. Specimens were obtained, graded for degree of atherosclerotic involvement, and treated within 48 hours of harvesting. Argon laser energy was applied using an air medium with energy densities of 200-> 20,000 J/cm² to investigate the effects of argon light on normal and atherosclerotic aorta. Specimens were examined grossly to determine degree of atherosclerosis present and to assess effects of the laser. Light microscopy was performed after staining with Hematoxylin and Eosin, Trichrome and Verhoff’s Elastin. The studies reported herein suggest that normal and non-calcified atherosclerotic aortas are comparable and predictable in rate of penetration and perforation by argon laser light (perforation time approximates 4 seconds at 500-600 W/cm²). When calcification is present in atherosclerotic lesions, the response to laser energy is less predictable. Calcium is a general retardent of laser vaporization of tissue and penetration of aortic wall. We find that the nature of an atherosclerotic lesion may affect resectability of atherosclerosis by argon laser. The incidence and severity of potential complications including acute thrombosis or accelerated atherogenesis in treated vessels, aneurysm formation and distal embolization awaits further study in chronic animal models.