Liệu cắt lớp quang học OCT có thể thay thế cho siêu âm trong lòng

mạch IVUS?

TS.BS. Nguyễn Quốc Thái Viện Tim Mạch Việt Nam

Siêu âm trong lòng mạch (IVUS) • IVUS (Intravascular ultrasonography) là phương pháp chẩn

đoán hình ảnh xâm nhập để cung cấp hình ảnh trong lòng mạch vành (cũng như các mạch máu khác).

Ứng dụng của IVUS can thiệp ĐMV

•Tính chất mảng xơ vữa

•Kế hoạch trước PCI

•Đánh giá kết quả sau PCI

•Phát hiện các biến chứng trong PCI

Tính chất mảng xơ vữa

Phân loại mảng xơ vữa: • Mềm (Soft): giàu lipid • Xơ hoá (Fibrotic): phần lớn • Vôi hoá (Calcium) • Hỗn hợp (Mix plaque)

Phân bố mảng xơ vữa: • Đồng tâm (concentric) • Lệch tâm (eccentric)

Ứng dụng của IVUS

Interventional Applications • Assessment of Target Lesion

Lesion severity, size, length, atheroma burden, Plaque distribution and depth, presence of thrombi or dissection

• Choosing balloon & stent Balloon sizing Stent sizing & length

• Need for rotational atherectomy

Proximal Reference Lesion Site (+ve

remodelling) Distal Reference

B1 B2

Assessment for Intervention Sizing DES era – Stent most normal prox. to most normal distal

• Use larger balloons at low pressures for unapposed stents

Optimal Stent Deployment Criteria

5 mm

Balloon

Needed

Assess Complications - Dissection

Stent edge dissection

1.5 mm 0 7.5 mm Dissection

2009 2011 2013 2014/2015 2016

C7-XR™ System ILUMIEN™ System ILUMIEN™ OPTIS™ System OPTIS™ Integrated

OPTIS™ Mobile

• First Frequency

Domain OCT System

• 100 fps / 500 lines

• Occlusion-free

• Combined FFR and OCT

• Wireless FFR

• Advanced software tools

• Real time 3D reconstruction

• Tableside control from DOC

• Fully Integrated into

Cath Lab

• Angio Co-registration

• Tableside Controller

• Angio Co-registration

• Tableside Controller

• Mobile cart connect into

Cath Lab during procedure

• For use in multiple

Cath Labs

Commitment to Innovation

• Flexible fiberoptic catheter used for light

delivery

• Catheter rotates to create image frames

• Catheter pulls back to map vessel

segment

How does it all work?

Normal coronary artery

Uniform silhouette

3 layers visible in vessel wall

Data on file at LLI

Imaging

catheter

Guidewire

shadow Adventitia

Media

Intima

Healthy Artery – Normal Appearance

The Role of OCT1

OCT Imaging

Pre-Intervention

Assessment

Stent Deployment

Apposition,

Expansion Final MSA,

and Geographical Miss

Complication

and Post Procedural

Assessments

1. Assess plaque composition

2. Identify reference segments

3. Choose stent size

4. Determine expansion/MSA

5. Determine apposition

6. Rule out geographical miss

7. Identify edge dissections

8. Identify tissue protrusion

9. Confirm procedural success

Ali, Ziad., When and How to Use OCT to Improve Procedural Outcomes. www.tctmd.com

OPUSS Class: This 5 Centre Prospective study reported first large comparative data between the

OCT versus matched IVUS images in human coronary arteries.

Fig 1. Adapted from Kubo T, et. Al.

High Resolution Leads to Measurement Accuracy

7.45

7.45±0.17

7.45

8.03±0.158

Fig 2. Adapted from Kubo T, et. Al.

Kubo T, et al. JACC Cardiovasc Imaging 2013;6:1095-1104

Selecting Stent Diameter

1

2 3.96

3.90 3.00

2.87

1 2

1. Maximum diameter of the smaller reference.

2. Average of the maximum diameters of the prox. and distal references.

3. Maximum diameter of the largest reference.

4. Mid-wall to mid-wall diameters (between lumen and media)

5. Media-to-media diameter

Increasingly

Aggressive

6. Abizaid, A. Use of Imaging to Optimize and Understand BRS. Presented at Coronary Intravascular Imaging and Physiology Symposium 2016.

LCX

Dx

LM

MLA 1.95 mm2

Ø = 1.56 mm, AS = 76.5%

From where to where?

Lesion length 26 mm

Area 8.29 mm2

Ø = 3.12 mm Area 8.32 mm2

Ø = 3.04 mm

PRE-INTERVENTION ASSESSMENT WITH AUTOMATIC

MEASUREMENTS1

Ali, Ziad., When and How to Use OCT to Improve Procedural Outcomes. www.tctmd.com

LCX

Dx

LM

MLA 1.95 mm2

Ø = 1.56 mm, AS = 76.5%

From where to where?

Area 8.32 mm2

Ø = 3.04 mm

Area 8.79 mm2

Ø = 3.25 mm

Lesion length 28 mm

PRE-INTERVENTION ASSESSMENT WITH AUTOMATIC

MEASUREMENTS1 Area 8.29 mm2

Ø = 3.12 mm

Ali, Ziad., When and How to Use OCT to Improve Procedural Outcomes. www.tctmd.com

OCT vs. IVUS

SO SÁNH GIỮA IVUS VÀ OCT

Vessel Sizing & BVS Choice:

Adapted from Orimiston et. al

Figure 1.

A,Stenosis in the obtuse marginal

branch of the left circumflex

coronary artery before ABSORB

bioresorbable vascular scaffold

(BVS) implantation;

B, artery after deployment of a

3.0X18 mm ABSORB BVS

scaffold and after dilatation with a

3.25-mm noncompliant

balloon at 24 atm.

“Strut discontinuity and malapposition are not evident angiographically….the problem is best detected by OCT”3

Fig. 1 mages Adapted

Ormiston et. al.

2.Ormiston et. al. Bioresorbable Polymeric Vascular Scaffolds: A Cautionary Tale. Circ Cardiovasc Interv. 2011;4:535-538

3.Gomez-Lara et. al. Agreement and Reproducibility of Gray-Scale Intravascular Ultrasound and Optical Coherence Tomography for the Analysis of he Bioresorbable Vascular Scaffold Catheterization and Cardiovascular Interventions 79:890–902 (2012)

OCT has limitations where IVUS can still offer superior imaging

OCT offers better image quality, but IVUS still has niche applications

“Gót chân Achilles” của OCT

Nhược điểm của OCT so với IVUS

1. Hạn chế dùng OCT cho BN có suy thận: do sử dụng can quang làm sạch máu trong quá trình thủ thuật

2. Không thu được hình ảnh tốt ở các tổn thương lỗ ĐM chủ (do không thể làm sạch máu từ ĐMC đến lỗ ĐM vành phải hoặc lỗ LMT).

3. Do khả năng đâm xuyên nông nên không đánh giá được gánh nặng mảng xơ vữa (plaque burden) ở những tổn thương tái cấu trúc (remodeling).

4. IVUS guide trong can thiệp tổn thương tắc mạn tính

IVUS in CTO PCI

IVUS guide

Các bằng chứng lâm sàng OCT vs. IVUS?

BULLET GUIDE BULLET GUIDE

HEADER GUIDE HEADER GUIDE

CLI-OPCI OCT improves outcomes vs. angiography

OPUS-Class Study Reliability of OCT measurement vs. IVUS and angiography

OCT Safety and Efficacy Non-occlusive OCT study

SJM Commitment to Clinical Evidence

ILUMIEN IV Randomized Controlled Outcomes Under Development

Others areas under consideration:

Bifurcation

BVS

ACS

ILUMIEN I Define and evaluate OCT stent guidance parameters and determine impact on physician decision-making.

ILUMIEN II OCT vs IVUS comparison of stent expansion

ILUMIEN III OCT/IVUS/Angio prospective randomized trial

Past

Present–2015

Future

A total of 1,002 lesions (832 patients) were assessed retrospectively at 5 High Volume OCT Centres

Patients had a complex lesion profile (Ellis Class B2/C) LM (4.8%), LAD (50.7%), LCx. (21.4%) RCA (22.7%) & Grafts (0.4%) Primary objective: The impact of the presence of an OCT-based suboptimal stent deployment on clinical outcome (MACE).

OCT-guided strategy during PCI8

OCT plus angio can improve clinical outcomes 8

Patients With Suboptimal OCT Deployment (n=254)

Patients With Optimal OCT Deployment (n = 578)

P value

Events at 1-year follow-up

MACE 64 (25.2%) 41 (7.1%) 0.001

Death 11 (4.3%) 13 (2.2%) 0.104

Myocardial infarction 42 (16.5%) 22 (3.8%) 0.001

Periprocedural MI 11 (4.3%) 11 (3.31.9%) 0.050

During follow-up 31 (12.2%) 11 (1.9%) 0.001

Target lesion repeat revascularization

42 (16.5%) 14 (2.4%) 0.001

Stent Thrombosis 26 (10.1%) 4 (0.7%) 0.001

Days of follow-up 312 (118-584) 324 (129-575) 0.536

Prati, F, Romagnoli, E, Burzotta, F., Limbruno, U….Clinical Impact of OCT Findings During PCI The CLI-OPCI II Study JACC: Cardiovasc. Imaging Vol. 8 , No. 11, 2015

CLINICAL HIGHLIGHTS FROM ILUMIEN II6

KẾT LUẬN

1. Siêu âm trong lòng mạch (IVUS) và chụp cắt lớp quang học nội mạch (OCT) đều có vai trò trong hướng dẫn can thiệp ĐMV làm giảm các biến cố cũng như cải thiện kết cục sau can thiêp.

2. Sự lựa chọn kỹ thuật chẩn đoán hình ảnh phụ thuộc vào vị trí cũng như tính chất tổn thương ĐMV.