1Chapter Label |

THE CLINICAL VALUE OFSPECTIN EVALUATING CORONARY ARTERY DISEASE

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Frontline providers are increasingly

responsible for a growing, aging

population at risk for coronary artery

disease (CAD).

Those who see at-risk patients first

may become more involved in disease

evaluation and care coordination for

appropriate cardiac testing.

The more we can understand about

the noninvasive cardiac testing options

available, the more we can work

together to help improve the quality of

care for what matters most—the patient.

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1 INTRODUCTION ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 2

Why SPECT?

2 ROLE IN CARDIAC TESTING ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 5

What Can SPECT Do?

3 MEANINGFUL RESULTS ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 6

SPECT Reveals Heart Disease

4 PATIENT POPULATION •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 9

Who Are Appropriate Candidates for SPECT?

5 CLINICAL VALUE ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 13

Using SPECT

6 RESOURCES ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 16

Learn More About Cardiac Testing

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INTRODUCTION

Why SPECT?For more than 40 years,

noninvasive radionuclide imaging

(RNI) has been used to detect

and manage CAD.1

Whether you’re a frontline

provider,a a cardiology specialist,

or any other healthcare provider,

the more you know about the

most commonly used imaging

procedure in nuclear cardiology,

the better you’ll understand

which patients are appropriate

candidates for the test.1,2

a Frontline providers are the first to see patients at risk for CAD and may include primary care physicians, obstetrician/gynecologists, internists, hospitalists, nurse practitioners, physician assistants, or other referring or ordering providers.

3Introduction |

4

CAD = coronary artery disease; CVD = cardiovascular disease; SPECT MPI = single-photon emission computed tomography myocardial perfusion imaging.

Figure 1. Putting It Into PerSPECTive: Identifying Today’s #1 Killer

An estimated 92.1 million adults in the United States have

some form of CVD, and approximately 1 in 3 deaths is

attributed to CVD.8,9

Almost half of all CVD deaths are due to CAD—it is the

leading cause of death for both men and women.8-10

Risk for CAD increases over time as the progression of

atherosclerosis (plaque buildup) partially or totally blocks

myocardial perfusion to the heart.10,11

SPECT can detect perfusion defects early in the disease

progression.12

InSPECTing the Name

You may have heard SPECT MPI—single-

photon emission computed tomography

myocardial perfusion imaging—referred to

as one of the following terms:

• Radionuclide imaging (RNI)

• Nuclear stress test

• Noninvasive cardiac imaging

• Cardiac nuclear scan

Detecting Disease With SPECT

For the many patients with CAD (Figure 1),

SPECT or hybrid SPECT/computed

tomography imaging may be helpful in disease

detection. However, SPECT is used for more

than just cardiac imaging. It can also be used

for bone scans3 and is well documented in the

detection and treatment of:

• Cancer4

• Alzheimer’s disease5

• Traumatic brain injury6

• Thyroid abnormalities7

5Role in Cardiac Testing |

STRESS

REST

STRESS

STRESS

STRESS

REST

REST

REST

Images courtesy of Kim Allan Williams, MD.

Figure 2. SPECT MPI Scans

SPECT is used for the detection of CAD,

risk stratification of patients with known or

suspected CAD, and guidance in clinical

management decisions.1,12

SPECT scans are taken using a gamma

camera, which captures images of

photons emitted by radiotracers as

they are taken up by viable myocytes

proportional to the amount of blood flow

to the heart. The SPECT radiotracers

are technetium-99m (Tc-99m) and

thallium-201 (Tl-201). A series of images

are taken to show different sections of the

heart. Scans are performed at stress and

rest (Figure 2).1,13,14

The color indicates areas of perfusion

where the radiotracer has entered the

myocardium. Areas that appear lighter

in color at rest and darker during stress

indicate stress-induced ischemia, where

blood flow is blocked.13

SPECT MPI is widely available and

accessible for patients who have

known or suspected heart disease.1,2

The standard MPI procedure uses

electrocardiogram (ECG) data as the

heart beats to guide image acquisition

(also known as ECG-gated SPECT).1

ROLE IN CARDIAC TESTING

What Can SPECT Do?

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SHORT AXIS VERTICAL LONG AXIS HORIZONTAL LONG AXIS

Figure 3. SPECT Scan Analysis

Images courtesy of Kim Allan Williams, MD.

MEANINGFUL RESULTS

SPECT Reveals Heart Disease SPECT scans show clinical information

about a patient’s heart health. Scan results

with multiple perfusion defects in different

coronary territories may indicate severe CAD.12

What Can SPECT Show?

As a functional imaging test, SPECT can help

detect perfusion defects.12

• Figure 3 shows how sections of the

myocardium are imaged in 3 axes to view

perfusion defects at different angles1

• Figure 4 shows where a SPECT scan

can detect perfusion defects in the

ischemic cascade12

• Figure 5 shows how perfusion defects

may be reversible, with perfusion

abnormalities at stress and normal

perfusion at rest, or irreversible, with

perfusion defects visible on both stress

and rest images, indicating greater risk

for myocardial infarction (MI)1

SPECT imaging can identify whether a prior

MI has occurred, as well as perfusion status

after cardiac procedures.1,13

SPECT provides prognostic value by

measuring end-systolic and end-diastolic

stroke volume.1

Imaging results can help determine

considerations for further evaluation

or procedures (eg, coronary angiogram, stent,

bypass surgery, medical therapy).1,15

• Gathering ECG information and data

on exercise capacity is also important for

diagnosis and prognosis12

SPECT scans can uncover transient ischemic

dilation, which may be associated with

extensive ischemia and severe CAD.1

SPECT scans can provide robust,

reproducible estimates of left ventricular

ejection fraction, adding incremental

prognostic information.1

SPECT can help identify severe multivessel

disease if significant lung uptake of

radiotracer is detected.1

7Meaningful Results |

Figure 4. Ischemic Cascade12

Figure 5. SPECT Perfusion Defects

Images courtesy of Kim Allan Williams, MD.

REST RESTSTRESS STRESS

FIXEDREVERSIBLE

Progression ofAtherosclerosis

PLA

QU

E B

UIL

DU

P

Vascular Dysfunction

Decreased Subendocardial Perfusion

Myocardial Metabolism Abnormalities

Diastolic Dysfunction

Decreased Epicardial Perfusion

Wall Motion Abnormalities

Global Systolic Dysfunction

Electrocardiogram Abnormalities

DU

RA

TIO

N O

F IS

CH

EM

IA

As ischemia becomes progressively worse

in severity and duration, it produces a

cascading sequence of functional changes

(abnormalities) in:

• Perfusion

• Relaxation and contraction

• Wall motion

• Repolarization

SPECT MPI = single-photon emission computed tomography myocardial perfusion imaging.

SPECT MPI

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9Patient Population |

PATIENT POPULATION

Who Are Appropriate Candidates for SPECT?This noninvasive imaging test can help evaluate

patients at risk for CAD. But how do you know

whether a SPECT test is right for your patient?

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SPECT can be considered an appropriate test

for the following16:

Patients with symptoms and• An uninterpretable ECG,

• An intermediate to high risk for CAD, or

• An inability to exercise adequately

Patients with or without symptoms and• Other cardiovascular conditions (such as

newly diagnosed heart failure), or

• In postrevascularization for evaluation of

ischemic equivalent symptoms or where

additional revascularization is feasible

Patients with poor or unknown functional capacity and

• Prior to kidney or liver transplant, or

• Prior to vascular surgery with ≥1 clinical

risk factor

Patients with new or worsening symptoms and• With normal or abnormal exercise ECG

results,

• With nonobstructive CAD on angiography

or normal prior stress imaging study results,

• With obstructive CAD on coronary

computed tomography angiography or

invasive coronary angiography, or

• With abnormal calcium score (Agatston

score >100)

Appropriate SPECT testing has important

implications for clinical decision-making.

Perfusion data provide prognostic information

about risk for adverse events, which may affect

patient management choices.1

Once SPECT has been deemed appropriate,

it is important to prepare patients for the

test by helping them understand what is

expected (Figure 6).

Determining Who Is Appropriate for a SPECT Test

11Patient Population |

ECG = electrocardiogram; SPECT = single-photon emission computed tomography.

Figure 6. What Patients Can Expect During a SPECT Test

1 Stress Test Patient ECG, heart rate, and blood pressure are

monitored during stress. Exercise is the preferred

stress method, but if patients are unable to exercise

adequately, a pharmacologic stress agent can be

used. Pharmacologic stress simulates exercise effects

by increasing blood flow to the heart.12,13,15

2 Radiotracer InjectionA small amount of radioactive tracer is injected into

the patient’s arm.13 The radiotracer is distributed

throughout the myocardial tissue proportional to

blood flow.1

3 Radionuclide ImagingA gamma camera captures images of myocardial

perfusion after stress and at rest for comparison.1,13

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13Clinical Value |

CLINICAL VALUE

Using SPECTThis advanced diagnostic

cardiac imaging procedure

provides valuable evaluation

and risk assessment

information that is

incremental to ECG data.1,12

14

a Learn more about the Centers for Medicare & Medicaid Services (CMS)

federal mandate at CardiacTesting.com

Why Use SPECT?

It can be used for the detection of CAD,

risk stratification of patients with known or

suspected CAD, and guidance in clinical

management decisions.1,12

It can be performed with exercise or

pharmacologic stress.12

It can help show perfusion defects in the early

stages of the ischemic cascade.12

Clinical benefits should be weighed against

potential risks, which may include radiation

exposure, injury, and interpretation error.16

The amount of radiation used in cardiac

testing with SPECT varies by protocol.14

Guideline-based appropriate use criteria

(AUC) may help define appropriate SPECT

tests for certain clinical scenarios.16,a

Future of SPECT

SPECT continues to be a valuable tool in the

evaluation and risk assessment for CAD.

Over time, several enhancements have

been made to SPECT camera hardware

and software.1

• New cameras acquire images in a fraction

of the time of older cameras, producing

better-quality scans in approximately

one-third of the time

• New technology reduces the amount

of radiotracer needed, minimizing

radiation exposure

• New techniques may reduce motion

artifacts and may improve patient comfort

15Clinical Value |

REFERENCES

1. Udelson JE, Dilsizian V, Bonow RO. Nuclear cardiology. In: Mann DL,

Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald’s Heart

Disease: A Textbook of Cardiovascular Medicine. 10th ed. Philadelphia,

PA: Elsevier Saunders, 2015:271-319. 2. American Society of Nuclear

Cardiology, MedAxiom. 2013 nuclear cardiology trend survey. J Nucl

Cardiol 2014;21(Suppl 1):5-88. 3. Fuster D, Solà O, Soriano A, et al. A

prospective study comparing whole-body FDG PET/CT to combined

planar bone scan with 67Ga SPECT/CT in the diagnosis of spondylodiskitis.

Clin Nucl Med 2012;37(9):827-32. 4. National Cancer Institute. Molecular

and Nuclear Imaging (PET and SPECT) (12-22-2016). https://imaging.

cancer.gov/imaging_basics/cancer_imaging/nuclear_imaging.htm.

Accessed 11-12-2017. 5. Alzheimer’s Association. Alzheimer’s and

Dementia Testing for Earlier Diagnosis. http://www.alz.org/research/

science/earlier_alzheimers_diagnosis.asp. Accessed 11-12-2017.

6. Raji CA, Willeumier K, Taylor D, et al. Functional neuroimaging

with default mode network regions distinguishes PTSD from TBI in a

military veteran population. Brain Imaging Behav 2015;9(3):527-34.

7. Shafiei B, Hoseinzadeh S, Fotouhi F, et al. Preoperative 99mTc-

sestamibi scintigraphy in patients with primary hyperparathyroidism

and concomitant nodular goiter. Nucl Med Commun 2012;33(10):1070-6.

8. Benjamin EJ, Blaha MJ, Chiuve SE, et al. Heart disease and stroke

statistics—2017 update. Circulation 2017;135(10):e146-603. Errata

in: Circulation 2017;135(10):e646; Circulation 2017;136(10):e196.

9. Kochanek KD, Murphy SL, Xu J, Tejada-Vera B. Deaths. Natl Vital

Stat Rep 2016;65(4):1-122. 10. National Heart, Lung, and Blood

Institute. What Is Coronary Heart Disease? (06-22-2016) https://

www.nhlbi.nih.gov/health/health-topics/topics/cad/. Accessed

04-24-2017. 11. American Heart Association. Atherosclerosis

(07-05-2017). http://www.heart.org/HEARTORG/Conditions/

Cholesterol/WhyCholesterolMatters/Atherosclerosis_UCM_305564_

Article.jsp#.WgDUB63-2gR. Accessed 11-06-2017. 12. Fihn SD, Gardin

JM, Abrams J, et al. 2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS

guideline for the diagnosis and management of patients with stable

ischemic heart disease. J Am Coll Cardiol 2012;60(24):e44-164.

13. American Heart Association. Single Photon Emission Computed

Tomography (SPECT) (09-19-2016). http://www.heart.org/

HEARTORG/Conditions/HeartAttack/DiagnosingaHeartAttack/

Single-Photon-Emission-Computed-Tomography-SPECT_

UCM_446358_Article.jsp. Accessed 07-25-2017. 14. Henzlova MJ,

Duvall WL, Einstein AJ, Travin MI, Verberne HJ. ASNC imaging

guidelines for SPECT nuclear cardiology procedures. J Nucl Cardiol

2016;23(3):606-39. Erratum in: J Nucl Cardiol 2016;23(3):640-2.

15. American Heart Association. Myocardial Perfusion Imaging (MPI)

Test (09-19-2016). http://www.heart.org/HEARTORG/Conditions/

HeartAttack/SymptomsDiagnosis ofHeartAttack/Myocardial-

Perfusion-Imaging-MPI-Test_UCM_446352_Article.jsp#. Accessed

12-11-2017. 16. Wolk MJ, Bailey SR, Doherty JU, et al. ACCF/AHA/ASE/

ASNC/HFSA/HRS/SCAI/SCCT/SCMR/STS 2013 multimodality

appropriate use criteria for the detection and risk assessment of

stable ischemic heart disease. J Am Coll Cardiol 2014;63(4):380-406.

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RESOURCES

Learn More About Cardiac Testing

Access online resources

Use an interactive risk score calculator

Download educational materials for your patients and practice

Register for a cardiac testing speaker event

For the latest information in cardiovascular care,

go to CardiacTesting.com

For more than 20 years, Astellas has offered practical

resources to help providers make decisions focused on

patient-centered care. Our educational materials are designed

to increase understanding of cardiac testing and encourage

communication between providers—all to help each patient

get the right cardiac test at the right time.

The Cardiac Testing Educational Series is intended to be a

starting point for further reading.

17Resources |

Astellas is committed to bringing you the latest information on cardiac testing, so your entire care team can be better equipped to help what matters most—the patient.

Go to CardiacTesting.com to learn more about the clinical value of SPECT MPI in cardiac testing.

Astellas® and the flying star logo are registered trademarks of Astellas Pharma Inc. ©2018 Astellas Pharma US, Inc. All rights reserved. 014-0032-PM 4/18

Shared Understanding of Cardiovascular Care