CATHETER SIZES FOR QUANTITATIVE CORONARY ARTERIOGRAPHY

In quantitative coronary arteriography (QCA), the outer diameter of th e contrast catheter is used almost exclusively as the calibration devi ce, Since the true outer diameter of these catheters are smaller than the French sizes listed by the manufacturer, it has been advocated to measure the actual sizes with a precision micrometer. However, this re presents a significant effort in the organizations of the QCA Angiogra phic Core Laboratories and of the participating cardiac catheterizatio n laboratories. In the Dutch REGRESS trial on regression/progression o f coronary artery disease, we have measured a total of 2,104 catheters from four different manufacturers. In 2,048 of the 2,104 catheters th e variabilities in the measurements were 0.02-0.03 mm, which represent s an error of only 1% of the average catheter sizes, In the remaining 56 catheter measurements, the variability was 0.04 mm, From these data we may conclude that from now on the stated mean values can be used f or calibration purposes. This has important practical consequences for running clinical trials and QCA Core Laboratory operations. (C) 1994 Wiley-Liss, Inc.