Size distribution of embolic material produced at aortic cross-clamp manipulation

Abstract

Objectives . The association between aortic atherosclerosis and neurological damage during cardiac surgery is well recognized. The purpose was here to analyze the size distribution of particles produced at cross-clamp manipulation of the ascending aorta. Design . A human cadaveric aortic perfusion model of retrograde design was applied (n = 27). With this model, washout samples were collected from the pressurized ascending aorta during cross clamp manipulation. Before the experiment, the aorta was fl ushed to remove debris and with a baseline sample collected. The cross-clamp was opened to collect ten repeated aliquots with dislodged particles. Collected washout samples were evaluated by digital image analysis and microscopy. Results . Cross-clamping produced a signifi cant output of particles, which was seen for size intervals of 1 mm and smaller (p = 0.002 to p = 0.022). In all size intervals the particle output correlated with the degree of overall aortic calcifi cation (p = 0.002 to p = 0.025). The model generated substantially more small-size particles than large debris (p < 0.010). Conclusions . Aortic clamping was here verifi ed to dislodge aortic debris which correlated with the degree of observed calcifi cation. Macroscopic particles were few. In contrast, cross-clamping produced substantial numbers of small-size particles. These fi ndings emphasize microembolic risks associated with cross-clamping of atherosclerotic vessels. © 2010 Informa Healthcare.