Atherosclerotic Plaque Detection via IVUS 应用 IVUS 检测动脉粥样硬化斑块 Fudan University, Zhongshan Hospital Shanghai Institute of CVD CIT 2010 Juying Qian, MD, FACC

Limitation of Coronary angiogram Focal lesion Diffuse lesion D% silhouette 50% Lower accuracy of quantitative assessment Little information of the plaque characteristics angiogram Positive remodeling

Coronary angiogram & IVUS

Volcano intravascular ultrasound BSC mechanical Phased array

Normal coronary artery The relationship between IVUS three layer and the biological intima, media and adventitia Intima is dense and will appear as a “white” layer between the media and the blood speckles. Adventitia is composed of collagen that highly reflected by ultrasound (appears white) Media is made of homogeneous smooth muscle cells and is not reflected by ultrasound (appears dark)

Normal coronary artery IVUS three layer does not equal to the biological intima, media and adventitia Abdomial aortic dissection

IVUS classcification of atherosclerosis Type I or II Initial lesion or fatty streak Stage I or II

IVUS classcification of atherosclerosis Type III Pre-atheroma Stage III

IVUS classcification of atherosclerosis Type IV atheroma Stage IV

IVUS classcification of atherosclerosis Type Va fibro-atheroma Stage V

Type Vb IVUS classcification of atherosclerosis fibro-atheroma Stage V

Type Vc IVUS classcification of atherosclerosis fibro-atheroma Stage V

IVUS classcification of atherosclerosis Type VIa: Plaque rupture or erosion complicated lesions Stage VI

IVUS classcification of atherosclerosis Type VIb: hematoma complicated lesions Stage VI

IVUS classcification of atherosclerosis Type VIc: thrombus complicated lesions Stage VI

IVUS classcification of atherosclerosis

Qualitative assessment Eccentric (>0.5)Concentric(<0.5) Eccentric index=0.45 Eccentric index= (atheroma thickness)max (atheroma thickness)max-(atheroma thickness)min Eccentric index=0.67 atheroma eccentricity

Qualitative assessment Atheroma morphology Soft plaqueFibrous plaque Calcified plaque

Qualitative assessment Thrombus Atheroma morphology

Qualitative assessment Unstable lesion plaque rupture and ulceration Contrast media

Characteristics of vulnerable plaue in IVUS ：  Area of echolucent zone>1mm 2 ；  Echolucent area/plaque area >20 ％；  Thickness of fibrous cap <0.7mm 。 Ge et al, Heart, 1999 Vulnerable plaque

Qualitative assessment pseudoaneurysm

Myocardial bridging: half-moon echolucent zone Systolic diastolic Qualitative assessment

Quantitative measurement Border indentification EEM Edge of intima

Quantitative measurement Lumen-csa=3.8mm2 Max Lumen D=2.4mm Min lumen D=2.1mm lumen Lumen area stenosis(%) = reference lumen-csa - lumen-csa reference lumen-csa

Quantitative measurement EEM-csa=14.2mm 2 Lumen-csa=3.8mm 2 EEM measurement Atheroma (plaque+media) area =( )mm 2 =10.4mm 2 Plaque burden=10.4/14.2=73.2%

Quantitative measurement Calcium measurement 95° 150° 240°

Realtime 3D IVUS imaging

29 Calculation of plaque volume by IVUS Proximal Fiduciary Site Distal Fiduciary Site Proximal Fiduciary Site Distal Fiduciary Site Images Courtesy of Cleveland Clinic Intravascular Ultrasound Core Laboratory

Virtual Histology-IVUS

31 REVERSAL ： primary endpoint –change of total plaque volume * 与基线相比进展 (P=0.001). † 与基线相比无变化 (P=0.98). Nissen SE et al. JAMA. 2004;291: P=0.02 总斑块体积变化百分比 普伐他汀 40 mg 阿托伐他汀 80 mg % 变化百分比

ESTABLISH Trial: atorvastatin 20mg baseline 6m FU Okazaki S, et al. Circulation. 2004; 110: m FU baseline Control atorvastatin

33 ESTABLISH ： change of plaque volume by IVUS *P< Okazaki S et al. Circulation. 2004:110: * * 绝对变化 (mm 3 ) 阿托伐他汀 20 mg 常规治疗 (%) LDL 自基线变化百分比 斑块体积绝对变化 (%) 斑块体积变化百分比 变化百分比 (%)

34 GAIN ：斑块体积的变化 P=0.19 治疗 1 年后斑块体积的绝对变化 (mm 3 ) Schartl M et al. Circulation. 2001;104: 斑块体 积的变 化 (mm 3 )

斑块体积高回声团块 ( 纤维斑块 ) 低回声团块 ( 富含脂质的斑块 ) 治疗 1 年后的平均变化 (%) * 10.1 阿托伐他汀 mg 常规治疗 高回声团块是斑块更稳定的标 志. 更多的高回声团块代表斑块 更稳定 GAIN ：斑块内容物的变化 *P=0.021 Schartl M et al. Circulation. 2001;104: 治疗 1 年后斑块内容物变化百分比 (%)

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