ASSESSMENT OF THE RESULTS OF PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY USING AN INTEGRATED ULTRASOUND IMAGING ANGIOPLASTY CATHETER

To evaluate the results percutaneous transluminal coronary angioplasty (PTCA), intravascular ultrasound imaging was performed in 32 proximal coronary arterial segments and in 16 atherosclerotic lesions after PT CA in 13 patients using a 5 Fr balloon catheter with an ultrasound tra nsducer mounted just proximal to the balloon. Simultaneous angiographi c measurements of vessel diameter were also performed using electronic calipers from contrast cine angiograms. There was good correlation be tween ultrasound and angiographic minimum luminal diameters of the nor mal proximal vessel (y = 0.59x + 1.49, r = 0.70, P<0.01, n = 32). Howe ver, the luminal diameter measured by intravascular ultrasound was sig nificantly greater than when measured by contrast angiography (2.81 +/ - 0.10 vs. 2.34 +/- 0.12 mm, n = 16, P<0.001, mean +/- SEM). Post-PTCA , there was good correlation between ultrasound and angiographic minim um luminal diameters of the lesion (y = 0.62x +/- 1.42, r = 0.76, P<0. 001, n = 16), but again luminal diameters were significantly greater w hen measured by intravascular ultrasound compared to contrast angiogra phy (2.61 +/- 0.08 vs. 1.89 +/- 0.10 mm, n = 16, P<0.001). Furthermore , residual stenosis was significantly less when determined by intravas cular ultrasound than by contrast angiography(7.3 +/- 2.0 vs. 18. +/- 2.1%, n = 16, P<0.001). Intravascular ultrasound was able to detect co ronary calcification that was not evident by contrast coronary angiogr aphy in 8 of 16 lesions. Post-PTCA, dissection was evident in four les ions by ultrasound, whereas dissection was appreciated in only three l esions by contrast angiography. We conclude that intravascular ultraso und can accurately measure the luminal diameter of coronary arteries b oth before and after PTCA and reveals more information about the lesio n characteristics than does conventional contrast angiography. (C) 199 4 Wiley-Liss, Inc.