Comparative study of intravascular ultrasound and coronary artery angiography in coronary artery disease

AIM: To compare and evaluate the effect of intravascular ultrasound (IVUS) and coronary artery angiography (CAG)in the diagnosis of coronary artery disease (CAD). METHODS: Patients with CAD or suspected CAD were enrolled in the study. Ninety-eight coronary artery segments from 88 patients were measured by IVUS and CAG and the characteristics of the plaques, the stenostic morphology and the severity of stenostic vessels revealed by the two techniques were compared. IVUS examinations demonstrated that the plaques were classified into 3 types according to different ultrasound patterns of tissue reflection: Calcification plaque (an intense characteristic echo reflection with dropout of echoes peripherally), hard plaque (an intense echo reflection greater than the adventitia echogenicity), and soft plaque (an echo reflection weaker than the adventitia echogenicity). RESULTS: The degree of arterial stenosis (percentages of stenosed arterial diameter) and the mean length in CAG were significantly less well shown by CAG compared with those by IVUS [(32.2±(8.7))% vs(41.4±9.6)%,(13.2±6.6)mm vs(22.8±8.5)mm, P0.01 respectively]. The rates of detection with IVUS were more than those with CAG for calcified lesion and eccentric lesion. CONCLUSION: CAG significantly underestimates the degree of vascular lesions. The lumen morphology and plaque characteristics not found in CAG can be revealed very well by IVUS. IVUS has important clinical value in the early diagnosis and intervention of CAD and suspected CAD.