PET myocard perfusion & viability

Riemer Slart

Nuclear Medicine Physician

Dept. of Nuclear Medicine and Molecular Imaging

University Medical Center Groningen, the Netherlands

Professor in Molecular Imaging, University of Twente, the Netherlands

EANM Cardiovascular committee

Global burden of cardiovascular disease

Cardiovascular disease is the leading cause of death worldwide

Nature, 493, S2–S3, 2013

Global Coronary & Cardiovascular Risk Scores

Greenland. J Am Coll Cardiol. 2010;56:e50-e103.

Slide 4

What cardiologists want to know:

• Does the patient have a CAD?

• CAD with a significant stenosis?

• What is the extend of the CAD?

• Of prognostic impact?

• What is the best therapy?

“The general gatekeeper principle” Coronary artery disease

Risk factors Clinics

Intermediate risk

(1-3%)

Noninvasive imaging

Low risk (<1%)

High risk (>3%)

Ischemic cascade CAD

Coronary stenosis & ischemia

Diameter stenosis 50%

Patient with ischemia

Patient with angiographic lesion

Dilemma: no perfect match

•Diameter stenosis 90%

•Dilemma: no perfect match

Patient with ischemia

Patient with angiographic lesion

Coronary stenosis & ischemia

Diagnosis of CAD: CVI techniques

Echocardiogram

MPS SPECT

MPS PET

CT angiography

Calcium scoring

Intracoronary echo

Coronary angiogram

Adenosine MRI

Non-invasive

Invasive

Dobu MRI

ECG

Indications of different imaging tests for the diagnosis of

obstructive CAD and for the assessment of prognosis in subjects without known CAD

•Guidelines on myocardial perfusion, Task Force ESC and EACTS, Eur H J 2010

PET(/CT) myocardial perfusion

PET-CT scanner

PET vs SPECT Pro’s:

•Better resolution

•Absolute quantification

•Real time imaging

Con’s :

•Costs

•Availability

PET tracers for myocardial perfusion

Sogbein et al Biomed Res Int. 2014

Absolute quantification 13N-ammonia: Hutchins model

• 3-compartments model (K1, K2, K3)

13N-ammonia free diffusible

13N-ammonia: glutamate into glutamin (synthetasis)

equilibrium

Absolute quantification: mL/gr/min

Time-activity curves

Myocardial Blood Flow (absolute values, ml/g/min)

Normal values 13N-ammonia

• Rest: 60-95 mL/min/100g

• Stress: 190-300 mL/min/100g

• In general: MPR > 2.0

• Depending on age and gender & technique

Blanksma et al., J Nucl Med 1995

Chilian WM, Circulation 1997

DeGrado et al, J Nucl Cardiol 1996

Muzik et al, J Am Coll Cardiol 1998

Sunderland et al, J Nucl Cardiol 2014

DIFFERENT SOFTWARE PACKAGES -PMOD, SYNGO, FLOWQUANT-

Dynamic 13N-ammonia PET: quantification (Syngo) mL/gr/min

Principle MPI/FDG PET scan -Visual analysis-

• NORMAL tissue normal normal

• INFARCTED tissue reduced reduced

• ISCHEMIC tissue normal reduced

Rest Stress

Uptake flowtracer

Preparation patient:

Glucose load, low fat?

Euglycaemic insulin clamp infusion system

Acipimox: fatty acid lowering agent

(aspirin needed)

PET protocol: ischemia & viability UMC Groningen

rest 13NH3

(gated) FDG

Viability

rest 13NH3

(gated) FDG

Viability & ischemia

adeno 13NH3

Shorter scan protocol?

Lazarenko SV et al, Med Center Alkmaar, NL

Residual activity correction (RAC)

Normal Hibernating Scar

PET Imaging

Flow/FDG Patterns

Match Mismatch Match

DCM

Viability testing rest 99mTc-tetrofosmin IQ SPECT and FDG cPET

99mTc-tetrofosmin IQ SPECT

FDG cPET

CABG MVP/ring

Case

• 67 yr male

• RF: hypertension, DM

• Dyspnoe, no angina

• Obese

• Previous MPS SPECT (MIBI) inconclusive

• Nevertheless ischemia?

rest, stress 13N-ammonia and (gated) FDG

Rest, stress 13N-ammonia and (gated) FDG

Polarmap and quantification

Results

• Rest: 52 mL/min/100g

• Stress: 68 mL/min/100g

• MPR: 1.27 (normal > 2)

• Regions: 5 regions ratio < 1

Coronary angiography

3 vessel disease: revascularisation

Prognostic value of MPR without intervention -Absolute quantification-

Tio, Slart et al., J Nuc Med 2010

Prognostic value of MPR after intervention -Absolute quantification-

Cardiac death MACE

Slart et al, J Nucl Med 2011

Joutsiniemi et al, Eur Heart J Cardiovasc Imag 2015

Absolute flow or myocardial flow reserve for

the detection of significant coronary artery disease?

15O-water PET study

104 patients with moderate pre-test likelihood of CAD

without previous myocardial infarction.

Reference: CAG

Dorbola et al, J Am Coll Cardiol, 2013

PERFUSION DEFECT SIZE ON MPI PET MULTICENTER TRIAL

N = 7000

Diagnostic Performance of MPI Using SPECT, cMRI, and PET Imaging for the Detection of Obstructive CAD: A Meta-Analysis

Jaarsma et al., J Am Coll Cardiol, 2012

•166 articles (n = 17,901) : 114 SPECT, 37 CMR, and 15 PET articles.

Morton et al, J Am Coll Cardiol 2012

PET vs MRI MPI

New developments

Screened 920

PET evaluable

782

Discontinued

31

SPECT evaluable

778

Angio evaluable

762

Total 755

SPECT+PET+ angio

Dosed

795

CAD+= 327

CAD-= 428

(CAD prev 43%)

Flurpiridaz PET phase 3 study

PET vs SPECT for overall CAD detection

(n=755)

Courtesy of J. Knuuti

Flurpiridaz PET phase 3 study

PET vs SPECT for overall CAD detection

(n=755)

Original read Re-read

Courtesy of J. Knuuti

Courtesy of J. Knuuti

Ammonia mini cyclotron

Sr/Rb generator

http://vrijuit.nl/chalet-nederland.aspx

Hybrid cardiac imaging: SPECT/CT and PET/CT. A joint position statement by the European Association of Nuclear Medicine (EANM), the European Society of Cardiac Radiology (ESCR) and the European Council of Nuclear Cardiology (ECNC)

Eur J Nucl Med & Mol Imag 2011