Evaluation of venous injury caused by a percutaneous mechanical thrombolytic device.

PURPOSE: To study venous injury caused by a prototype percutaneous mechanical thrombolytic device. METHODS: Simulated thrombolysis was performed using the device, or the Fogarty balloon catheter (FBC) as control, in the infrarenal inferior vena cava (IVC) of 40 New Zealand white rabbits. Venous injury was evaluated by cavography, Evans blue dye staining, and histology at 0, 1, and 6 weeks postprocedure. RESULTS: Both devices resulted in near complete endothelial denudation acutely. No differences in reendothelialization were noted at any time in the proximal and mid-IVC, but there was significantly greater reendothelialization in the distal IVC in the rabbits treated 6 weeks earlier with the device (p < or = 0.04). Additionally, the inner luminal diameter at necropsy for the 1-week rabbits treated with the FBC was significantly narrower in the distal and middle sections of the IVC when compared with the device (p < or = 0.02 for both segments). There was no luminal diameter difference at 0 or 6 weeks. CONCLUSION: Based on a rabbit model, venous injury from the device was found to be similar to, and in the distal IVC less than, the routinely used FBC.

Starches of varied digestibilities differentially modify intestinal function in rats.

Starches of different digestibilities may enter the colon to different extents and alter colonic function. Male Fischer 344 rats were fed diets containing 25% cooked potato starch, arrowroot starch, high amylose cornstarch or raw potato starch for 6 wk. Fecal weight, transit time, colonic thymidine kinase activity (a marker for cell proliferation), and weight, starch content and pH of the cecum and proximal and distal colon were measured. Raw potato starch was much less completely digested than high amylose cornstarch, resulting in a 32-fold greater amount of undigested starch entering the cecum in the raw potato starch group. Both the high amylose cornstarch and raw potato starch diets significantly enhanced fecal weight and produced large intestinal hypertrophy, effects that were greatest in the raw potato starch group. Raw potato starch feeding was associated with the highest level of thymidine kinase activity, although the differences in thymidine kinase activity among the four groups were not significant. This diet also produced a 50% longer transit time. Entry of a large amount of raw potato starch into the colon resulted in greater luminal acidity, greater luminal bulk and slower transit. A much smaller amount of starch entered the colon in the high amylose cornstarch group and resulted in fecal bulking but no alteration in transit.