Atherosclerotic Plaque Detection via IVUS 应用 IVUS 检测动脉粥样硬化斑块 Fudan...

Atherosclerotic Plaque Detection via IVUS

应用 IVUS 检测动脉粥样硬化斑块

Fudan University, Zhongshan HospitalShanghai Institute of CVD

CIT 2010

Juying Qian, MD, FACC

Limitation of Coronary angiogram

Focal lesion

Diffuse lesion

D%silhouette

50%

50%

• Lower accuracy of quantitative assessment • Little information of the plaque

characteristics

angiogramPositive

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 IIInitial lesion or fatty streak

Stage I or II

IVUS classcification of atherosclerosis

Type IIIPre-atheroma

Stage III

IVUS classcification of atherosclerosis

Type IVatheromaStage IV

IVUS classcification of atherosclerosis

Type Vafibro-atheromaStage V

Type Vb

IVUS classcification of atherosclerosis

fibro-atheromaStage V

Type Vc

IVUS classcification of atherosclerosis

fibro-atheromaStage V

IVUS classcification of atherosclerosis

Type VIa:Plaque rupture or erosion

complicated lesions

Stage VI

IVUS classcification of atherosclerosis

Type VIb:hematoma

complicated lesionsStage VI

IVUS classcification of atherosclerosis

Type VIc:thrombuscomplicated 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 assessmentAtheroma morphology

Soft plaque Fibrous plaque Calcified plaque

Qualitative assessment

Thrombus

Atheroma morphology

Qualitative assessmentUnstable lesion

plaque rupture and ulceration

Contrast media

Characteristics of vulnerable plaue in IVUS ：Area of echolucent zone>1mm2 ；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 measurementBorder 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=14.2mm2

Lumen-csa=3.8mm2

EEM measurement

Atheroma (plaque+media) area =(14.2-3.8)mm2=10.4mm2

Plaque burden=10.4/14.2=73.2%

Quantitative measurementCalcium measurement

95° 150° 240°

Realtime 3D IVUS imaging

29

Calculation of plaque volume by IVUS

ProximalFiduciary Site

Distal Fiduciary Site

Proximal FiduciarySite

DistalFiduciary Site

Images Courtesy of Cleveland Clinic Intravascular Ultrasound Core Laboratory

Virtual Histology-IVUS

31

2.7%*

-0.4%†

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

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;291:1071-1080.

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: 1061-68

6m FU

baselineControl atorvastatin

33

-50

-40

-30

-20

-10

0

ESTABLISH ：change of plaque volume by

IVUS

*P<0.0001Okazaki S et al. Circulation. 2004:110:1061-1068.

-41.7*

-0.7

-15

-10

-5

0

5

108.7

-13.1*-10.0

-5.0

0.0

5.0

绝

对变

化 (

mm

3)

4.2

-8.3

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 (

%)

变化

百分

比 (

%)

34

9.6

1.2

0

2

4

6

8

10

12

常规治疗 阿托伐他汀20-80mg

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 (mm3)

Schartl M et al. Circulation. 2001;104:387-392.

斑块体积的变

化(mm3)

35

-0.3-2.1

42.2

2.5

11.8

-10

0

10

20

30

40

50

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 20-80 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=0.021Schartl M et al. Circulation. 2001;104:387-392.

治疗 1 年后斑块内容物变化百分比 (%)

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