Objective To investigate the pathologic characteristics of acute coronary syndrome(ACS) and stable angina(SA) through intravascular ultrasound(IVUS). Methods The study consisted of 131 coronary disease patients who underwent coronary artery angiography (CAG)and IVUS, ACS was diagnosed in 52 cases (unstable angina 34 cases and acute myocardial infarction 18 cases) and SA in 79 cases. IVUS examinations: plaque was classified into 3 types according to different ultrasound patterns of tissue reflection. (1) Calcification plaque appeared on ultrasound as an intense characteristic echo reflection with dropout of echoes peripherally, which was termed shadowing. (2)Hard plaque appeared on ultrasound as an intense echo reflection greater than the adventitia echogenicity.(3)Soft plaque appeared on ultrasound as an echo reflection weaker than the adventitia echogenicity. Unstable plaque was lipid-rich pool and thin fibrotic cap and plaque rupture, stable plaque was calcification plaque and hard plaque. Results Patients with ACS had more unstable plaque. 61.5% patients with ACS and 38.0% patients with SA had soft plaque(P

Objective To investigate the recent and long term effects of Radius stent through intravascular ultrasound(IVUS).Methods The study consisted of 147 coronary disease patients who had implanted self expanding Radius stent in chosen time.Coronary artery angiography and IVUS were performed to evaluate the clinical outcomes of Radius stent before and after the implantation.All the patients were followed up six months approximately after the implantation.Results The implantation success rate and clinical success rate of Radius stent were 99.5% and 98.9% respectively, restenosis rate was 10.8% at follow up examination for 6.4 months.The IVUS measurements showed that the lumen area was extended from 2.7 mm 2 to 5.3 mm 2 after the implantation and stent area was 7.6 mm 2 after about 6.4 months,but since intimal hyperplasia area was 2.6 mm 2,real lumen area was 5.0 mm 2 at follow up, which was a little smaller than that of the stent implantation at once.Conclusions IVUS showed a lower occurrence of restenosis for Radius stent,which is of value to its clinical application.