Angioscopic versus angiographic detection of intimal dissection and intracoronary thrombus

OBJECTIVES: This study was undertaken to compare coronary angioscopy with angiography for the detection of intimal dissection and intracoronary thrombus. BACKGROUND. It has been demonstrated previously that coronary angioscopy provides more intravascular detail than cineangiography. Both imaging methods have to be compared directly to assess the additional diagnostic value of angioscopy. METHODS. The angiograms and videotapes of 52 patients who had undergone angioscopy were reviewed independently by two observers unaware of other findings. Classic angiographic definitions were used for dissection and thrombus. Angioscopic dissection was defined as visible cracks or fissures on the lumen surface or mobile protruding structures that are contiguous with the vessel wall. Angioscopic thrombus was defined as a red, white or mixed red and white intraluminal mass. RESULTS. Angiography and angioscopy were in agreement in 40.4% of cases in the absence of thrombus and in 11.5% in the presence of thrombus. No fewer than 25 (48.1%) angioscopically observed thrombi remained undetected at angiography. With angioscopy as the standard, although the specificity of angiography for thrombus was 100%, sensitivity was very low at 19%. Angioscopic dissection was present in 40 patients (76.9%) versus angiographic dissection in 15 patients (28.8%). With regard to dissection, there was no correlation between the two imaging methods (r phi = 0.15, p = 0.29). CONCLUSIONS. Coronary angiography underestimates the presence of intracoronary thrombus. Angioscopy and angiography are complementary techniques for detecting and grading intimal dissections.