Henry Bom, MD, PhD, FANMB

Prof., CNU Med Sch, S. Korea President, AOFNMB

IPET 2015.10.09.

Disclosure

No conflict of interest

Issues for Cardiac Multimodality Imaging

• PETCT: Plaque imaging

• PETMRI: Cardiac sarcoidosis

• Flow reserve

Higher the FDG uptake Earlier the CVD event

Arterial FDG uptake on cancer surveillance

improves incident prediction of cardiovascular disease

FDG PET imaging of atherosclerosis is a reliable and reproducible measure of

vascular inflammation, which can be used as a

surrogate end point in clinical drug trials.

Tarkin JM et al. Nat Rev Cardiol 2014

Features of high-risk atherosclerotic plaques

High macrophage density Neovascularization PET

Features of high-risk atherosclerotic plaques

Thin fibrous cap Low collagen content Few smooth muscle cells Large, lipid-rich necrotic core Expansive (outward) remodeling ‘Spotty’ (micro)calcification Intra-plaque hemorrhage

IVUS OCT

Features of high-risk atherosclerotic plaques

Thin fibrous cap Low collagen content Few smooth muscle cells Large, lipid-rich necrotic core Expansive (outward) remodeling Intra-plaque hemorrhage ‘Spotty’ (micro)calcification

IVUS OCT

CT

In pts without confirmed CAD next step according to the likelihood of stable CAD • 61~90% invasive CAG • 30~60% MPI • 10~29% CT calcium

No calcium No further test

Can we use AC-CT for coronary calcium?

Comparison of ACS by AC-CT according to SPECT results

n=225, p = 0.049

121.2 ± 319.3

319.3 ± 681.5

Pts: MI 40, stable angina 40 F-18 NaF & F-18 FDG PET

Invasive CAG

Acute STEMI

18F-NaF 18F-FDG tissue-to-background ratios: culprit 2·27 versus reference segment 1·09

culprit 1.63 versus reference segment 1·91

Invasive CAG Acute STEMI

Culprit & Non-culprit

lesions

tissue-to-background ratios: culprit 2·03 versus reference segment 1·08

culprit 1.62 versus reference segment 1·49

18F-NaF 18F-FDG

CAG Non-obstructive

RCA lesion

18F-NaF IVUS tissue-to-background ratio

3.13

18F-NaF Carotid endarterectomy

Summary 1

• FDG & NaF PET/CT are useful plaque imaging tools. • We can add valuable information of plaques to oncology reports

Ga-67 scan

Immunosuppressive Therapy Response

Responder Nonresponder

Clinically ~5% of patients with sarcoidosis show cardiac symptoms. Baughman et al. Am J Respir Crit Care Med 2001 Autopsy 13~25% involve heart in the United States Silverman et al. Circulation 1978 Autopsy 58~85% involved heart in Japan Iwai et al. Sarcoidosis 1994

Asymptomatic Fatal Conduction Abnormality

Presentation of Cardiac Sarcoidosis

HRS expert consensus: Diagnosis and Management Arrhythmia associated with Cardiac Sarcoidosis

Biopsy proven extra-cardiac sarcoidosis

Cardiac history, ECG, Echocardiography

1. Symptom positive (palpitation, syncope) 2. Abnormal ECG 3. Abnormal Echocardiogram

One or more of 1~3

Advanced cardiac imaging: MRI or PET

None of 1~3

Low probability of CS

Heart Rhythm 2014; 11:1305-23

Fasting 6 hr Fasting + Heparin 12 hr 50 IU/kg

IV unfractionated heparin activates lipoprotein and hepatic lipases, thereby increasing plasma free fatty acid levels, and ultimately causing a reduction in glucose consumption of normal myocytes. (iv 15 min before FDG)

PET/MRI in Cardiac Sarcoidosis

Eur Heart J 2014

Ammonia FDG

FDG

PET/MRI in Cardiac Sarcoidosis

Eur Heart J 2014

Treatment was started using corticosteroids and a medical heart failure regime. However, MRI after 4 months revealed still impaired LV-function of 27% (Panel G). This finding and the

presence of a complete left bundle branch block provided the indication for cardiac

resynchronization therapy (CRT-D) (Panel I).

Serial assessment of edema and LGE by MRI as well the inflammatory status using FDG PET may be helpful for therapy-monitoring and guidance of primary preventive device therapy.

Summary 2

1. FDG PET/CT is accurate for diagnosis of sarcoidosis especially for the diagnosis of extra-pulmonary involvement.

2. Cardiac involvement of sarcoidosis is sometimes life-threatening. It can be diagnosed by heparin loading protocol of FDG PET/CT or MRI. Target for biopsy or for ICD application can be decided by it.

3. Immunosuppressive therapy effect can be monitored.

Fractional Flow Reserve (FFR)

Definition: the pressure behind (distal to) a stenosis relative to the pressure before the stenosis

Pijls, NH et al, Measurement of Fractional Flow Reserve to Assess

the Functional Severity of Coronary-artery Stenosis.

New Engl J Med 1996;334:1703

Optimal medical therapy PCI / revascularization

1.0 0.80 0.75 0

Fractional Flow Reserve (FFR)

CFR

FFR

N=69 r = 0.566

Correlation analysis

CFR

FFR

No plaques Non-obstructive plaques Obstructive plaques

FFRPET

CFR

Discordant lesions

P = 0.023

FFR

CFR

Focal lesions show lower FFR Diffuse lesions show lower CFR

diffuse

focal

Summary 3

1. CFR is an indicator for diffuse (microvascular) disease.

2. FFR is an indicator for focal disease, therefore better indicator for coronary intervention.

Issues for Cardiac Multimodality Imaging

• PETCT: Plaque imaging

• PETMRI: Cardiac sarcoidosis

• Flow reserve