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Society of Nuclear Medicine Procedure Guideline for
Myocardial Perfusion Imaging
version 3.0, approved June 15, 2002

Authors: H. William Strauss, MD (Memorial Sloan Kettering Cancer Center, New York, NY); D. Douglas Miller, MD (Saint
Louis University Health Sciences Center, St. Louis, MO); Mark D. Wittry, MD (Saint Louis University Health Sciences
Center, St. Louis, MO); Manuel D. Cerqueira, MD (Georgetown University Medical Center, Washington, DC); Ernest V.
Garcia, PhD (Emory University Hospital, Atlanta, GA); Abdulmassi S. Iskandrian, MD (Allegheny University of the
Health Sciences, Philadelphia, PA); Heinrich R. Schelbert, MD, PhD (UCLA School of Medicine, Los Angeles, CA); Frans
J. Wackers, MD, PhD (Yale University School of Medicine, New Haven, CT); Helena R. Balon, MD (William Beaumont
Hospital, Royal Oak, MI); Otto Lang, MD (Third Medical School, Charles University, Prague, Czech Republic); and Josef
Machac, MD (Mount Sinai School of Medicine, New York University, NY).

I. Purpose ing as a result of coronary artery disease (CAD)
and/or abnormal coronary flow reserve will have a
The purpose of this guideline is to assist nuclear zone of diminished radiopharmaceutical concentra-
medicine practitioners in recommending, perform- tion in the area of decreased perfusion. If either the
ing, interpreting, and reporting the results of my- area or severity of decreased tracer concentration is
ocardial perfusion imaging studies. worse when the tracer is administered during stress
than rest, the zone of decreased tracer concentration
II. Background Information and Definitions most likely represents ischemia. If the area of di-
minished tracer concentration remains unchanged,
Myocardial perfusion imaging (MPI) utilizes an in- even after injection at rest, the defect most likely
travenously administered radiopharmaceutical to represents scar, although in a significant number
depict the distribution of nutritional blood flow in of cases, it may represent viable, underperfused
the myocardium. Perfusion imaging identifies areas myocardium.*In addition to regional perfusion,
of reduced myocardial blood flow associated with recording the data with both SPECT and ECG gat-
ischemia or scar. The relative regional distribution of ing permits calculation of global and regional ven-
perfusion can be assessed at rest, cardiovascular tricular function and assessment of the relation-
stress, or both. Imaging can also be performed dur- ship of perfusion to regional function.
ing acute events (e.g., chest pain of unknown etiol-
ogy, such as in the coronary care unit or emergency
department). Perfusion images can be recorded with
III. Common Indications (see Table 1)
planar or tomographic single-photon or tomo- A. Assess the presence, location, extent, and sever-
graphic positron imaging techniques, utilizing ra- ity of myocardial perfusion abnormalities.
diopharmaceuticals that are extracted and retained B. Determine the significance of anatomic lesions
for a variable period of time by the myocardium. The detected by angiography
data can be analyzed by visual inspection and/or by C. Detect viable ischemic myocardium
quantitative techniques. Some radiopharmaceuti-
cals employed for MPI and approved by the U.S.
IV. Common Clinical Settings for Myocardial
Food and Drug Administration (FDA) include: Tl-
Perfusion Imaging
201 and the Tc-99m–labeled radiopharmaceuticals,
such as sestamibi, tetrofosmin, and teboroxime, for A. Known or Suspected CAD
single-photon imaging and Rb-82 for PET imaging. 1. Diagnosis of physiologically significant CAD
Patients with significant coronary artery narrow- (presence and severity)

* Such fixed abnormalities may also represent high-grade obstruction in zones of viable, hibernating myocardium. When
Tl-201 is used as the radiopharmaceutical, redistribution of tracer on delayed images may be useful to distinguish these
lesions from scar. When Tc-99m–labeled radiopharmaceuticals are used, administering nitroglycerin before injection at
rest may help make this distinction by improving perfusion (and tracer uptake) in the severely ischemic but viable re-
gion. Patients who fail to demonstrate myocardial viability with conventional SPECT imaging techniques may benefit
from F-18 FDG PET imaging, especially those patients with marked left ventricular dysfunction.

10 • MYOCARDIAL PERFUSION IMAGING

2. Determine prognosis (risk stratification based medications should be withheld if the exami-
on extent and severity of myocardial perfusion nation is performed to detect coronary disease
abnormalities and left ventricular function (see additional information later in this guide-
3. Differentiate between coronary and noncoro- line). Cardiac medication should be taken as
nary causes in patients with acute chest pain usual when the examination is performed to
syndromes seen in the emergency room determine the effectiveness of medical ther-
B. Follow-Up of Patients with Known CAD apy. Radiopaque objects in the area of the
1. Evaluate the immediate and long-term ef- thorax should be removed before imaging;
fects of: implanted radiopaque objects (metal, silicone,
a. Revascularization procedures (such as etc.) should be noted as potential attenuators
coronary artery bypass grafting, angio- of cardiac activity. In patients with severe
plasty, stent placement, use of angiogenic coronary disease, it may be advisable to ad-
growth factors, etc.). minister nitroglycerin sublingually about 3
b. Medical or drug therapy, whether de- minutes before rest injection of the radiophar-
signed to prevent ischemia (e.g., drugs that maceutical.
alter myocardial metabolic oxygen sup- 2. Exercise stress MPI
ply/demand relationship) or modify lipids Graded exercise stress is usually performed
and other features of atherosclerotic with a treadmill or bicycle ergometer with
plaque (e.g., statin drugs). continuous patient monitoring. All stress pro-
C. Known or Suspected Congestive Heart Failure cedures must be supervised by a qualified
1. Differentiate ischemic from idiopathic car- health care professional and performed in ac-
diomyopathy cordance with American Heart Associa-
2. Help assess whether patient has sufficient vi- tion/American College of Cardiology guide-
able myocardium overlying the infarction to lines. A fasting state is recommended for a
consider revascularization minimum of 4 hours before the stress study.
In general, patients undergoing a stress study
should be hemodynamically and clinically
V. Procedure
stable for a minimum of 48 hours before test-
A. Patient Preparation ing. Although patients who are unable to ex-
1. Rest-injected MPI ercise for noncardiac reasons (e.g., severe pul-
Patients should be fasting for at least 4 hours monary disease, arthritis, amputation,
(preferably for 12 hours) before MPI. Cardiac neurological disease, etc.) may be stressed

Table 1

Summary of Clinical Indications for Myocardial Perfusion Imaging

•Diagnosis of coronary artery disease
-Presence
-Location (coronary territory)
-Severity

•Assessment of the impact of coronary stenosis on regional perfusion

•Help distinguish viable ischemic myocardium from scar

•Risk assessment and stratification
-Postmyocardial infarction
-Pre-operative for major surgery in patients who may be at risk for coronary
events

•Monitor treatment effect
-After coronary revascularization
-Medical therapy for congestive heart failure or angina
-Lifestyle modification

SOCIETY OF NUCLEAR MEDICINE PROCEDURE GUIDELINES MANUAL JUNE 2002 • 11

pharmacologically with drugs designed to of the radiopharmaceutical to reverse the
cause coronary hyperemia or increased car- effects of the vasodilator. This is usually
diac work (see Table 2), exercise stress is pre- not required for adenosine, because of its
ferred because it provides additional prog- short duration of action, but aminophylline
nostic information. may be necessary when symptoms persist
If not medically contraindicated, it is rec- even after cessation of adenosine.
ommended that medications such as calcium b. Ino/chronotropic adrenergic agents (i.e.,
channel blocking drugs and beta-blocking dobutamine) be administered to increase
drugs that may alter the heart rate and blood myocardial oxygen demand. Drugs that
pressure response to exercise should be with- may blunt the chronotropic response to
held on the day of diagnostic studies. A se- adrenergic stimulant stress with dobu-
cure intravenous line should be established tamine (i.e., beta-adrenergic blocking
for the administration of the radiopharma- agents) should be discontinued before the
ceutical during stress. Patients undergoing procedure, if possible. Atropine may be re-
exercise stress should wear suitable clothing quired in some patients to increase the
and shoes. heart rate response, although increasing
3. Pharmacologic stress the heart rate by atropine does not cause
Two types of pharmacologic stress are useful the same increment in coronary blood flow
to evaluate myocardial perfusion: as does a similar increment in heart rate in-
a. Vasodilator stress agents may be adminis- duced by exercise. Patients should be fast-
tered to create coronary hyperemia (i.e., ing for a minimum of 4 hours before phar-
dipyridamole, adenosine). Caffeine-con- macologic stress testing. Although
taining beverages and methylxanthine- dobutamine is in routine clinical use for
containing medications, which interfere pharmacologic stress, it is not an FDA-ap-
with the coronary hyperemia produced by proved indication for the drug.
these drugs, should be discontinued for at B. Information Pertinent to Performing the Proce-
least 12 hours before pharmacologic stress dure
imaging (longer for long-acting methylx- A cardiovascular medical history and cardiores-
anthine preparations). When possible, pa- piratory examination, including baseline vital
tients may also undergo low-level exercise signs, should be obtained before stress studies.
to minimize symptoms associated with the Specific areas in the medical history requiring at-
vasodilators and to minimize subdi- tention are the indication for the examination,
aphragmatic tracer uptake. When dipyri- medications, symptoms, cardiac risk factors, and
damole is employed as the vasodilator, prior diagnostic or therapeutic procedures. Spe-
aminophylline (or a caffeinated beverage) cial attention must be directed to determine
may be administered after administration whether the patient may have an unstable coro-

Table 2
Modalities for Stress Testing

•Exercise
-Submaximal
-Symptom limited
-Maximal

•Pharmacological stress
-Vasodilators
Adenosine
Dipyridamole
-Inotropic
Dobutamine
Dobutamine + atropine


nary syndrome or aortic valve stenosis that syndrome should not be tested with adeno-
could increase the risk of stress. Patients should sine because of its negative dromotropic (SA +
also be assessed for obstructive airway disease AV node) effect. Additional contraindications
that could increase the risk of bronchospasm to vasodilator agents include severe aortic
with infusion of dipyridamole or adenosine. A stenosis, severe obstructive hypertrophic car-
12-lead electrocardiogram (ECG) should be re- diomyopathy, and severe orthostatic hy-
viewed for evidence of acute ischemia, arrhyth- potension. The use of dipyridamole or adeno-
mia or conduction disturbances (i.e., left bundle sine is not recommended in pregnant or
branch block [LBBB]), before stress MPI. Diabetic lactating females.
patients requiring insulin should be evaluated Ino/chronotropic agents are contraindicated
on a case-by-case basis to optimize diet and in- in patients with ventricular tachyarrhyth-
sulin-dosing on the day of the examination. In mias. These agents should be used with cau-
patients with LBBB. it is useful to use vasodilator tion in patients with unstable angina, obstruc-
stress to minimize the effect of the abnormal sep- tive or hypertrophic myopathy, or soon after
tal wall motion on the myocardial image of “per- acute infarction.
fusion.” 3. Cardiac emergency precautions
C. Precautions/Contraindications Life support instrumentation and emergency
1. Exercise stress drugs must be available in the immediate
Contraindications to exercise testing are un- vicinity of the stress laboratory. A physician
stable angina with recent (<48 hours) angina or other trained medical personnel currently
or congestive heart failure, documented acute certified in advanced cardiac life support
myocardial infarction (MI) within 2–4 days of (ACLS) must be immediately available during
testing, uncontrolled systemic (systolic >220 the stress and recovery phases. Continuous
mmHg, diastolic >120 mmHg) or pulmonary ECG monitoring must be performed during
hypertension, untreated life-threatening ar- the stress and recovery phases. Vital signs
rhythmias, uncompensated congestive heart (heart rate and blood pressure) and a 12-lead
failure, advanced atrioventricular block ECG should be recorded at regular intervals
(without a pacemaker), acute myocarditis, throughout the stress and recovery phases.
acute pericarditis, severe mitral or aortic The patient should be questioned at regular
stenosis, severe obstructive cardiomyopathy, intervals (e.g., every 1–2 minutes) for symp-
and acute systemic illness. Relative con- toms of myocardial ischemia or the side ef-
traindications to exercise stress include condi- fects of pharmacologic stress agents using a
tions that may interfere with exercise, such as standardized scale (e.g., 1 = very light to 10 =
neurologic, orthopedic, arthritic, or severe most severe). Patients with implanted defib-
pulmonary disease or peripheral vascular dis- rillator devices may require temporary ad-
ease, severe deconditioning, or inability to justment of their device to prevent stress-in-
comprehend the exercise protocol. duced triggering. Failure of monitoring
2. Pharmacologic stress equipment is an absolute indication to stop
Patients with a history of severe bron- exercise.
chospasm, pulmonary disease (i.e., asthma or 4. Occupational Safety and Health Administra-
pulmonary hypertension), prior intubation tion (OSHA), Nuclear Regulatory Commis-
for severe pulmonary disease, systemic hy- sion, and state regulatory guidelines
potension (systolic <90 mmHg), severe mitral It is mandatory that all regulatory guidelines
valve disease, or prior hypersensitivity to for the safe handling of syringes, needles, ra-
dipyridamole or adenosine should not un- dioactive materials, and patient waste be fol-
dergo vasodilator stress with dipyridamole or lowed at all times.
adenosine. Patients requiring methylxan- D. Radiopharmaceuticals
thine-containing medications to control their The following single-photon–emitting radio-
bronchospasm should not be tested with va- pharmaceuticals are FDA approved for use as
sodilator agents. Ino/chronotropic agents myocardial perfusion tracers: Tl-201, Tc-99m ses-
may be employed in these patients. Patients tamibi, Tc-99m teboroxime, and Tc-99m tetrofos-
with mild bronchospasm may undergo va- min. The following positron-emitting radiophar-
sodilator stress testing, particularly after pre- maceutical is approved for use as a myocardial
treatment with an albuterol inhaler. perfusion tracer: Rb-82. FDA recommendations
Patients with advanced (second- or third- for the maximum administered dose for a com-
degree) atrioventricular block or sick sinus bined rest and stress study (performed on the


Radiation Dosimetry for Adults*
Radiopharmaceutical Administered Organ Receiving the Effective Dose+
Activity Largest Radiation Dose+ mdose
MBq mGy per MBq mSv per MBq
(mCi) (rad per mCi) (rem per mCi)
T1-201 chloride1 75 – 150 i.v. 0.46 0.23
Kidneys
(2 – 4) (1.7) (0.85)
Tc-99m sestamibi2 750 – 1100 i.v. 0.039 0.0085
Gallbladder
(20 – 30) (0.14) (0.031)
Tc-99m teboroxime 1100 – 1850 i.v. 0.034 0.011
ULI
(30 – 50) (0.13) (0.041)
Tc-99m tetrofosmin 750 – 1500 i.v. 0.031 0.0067
Gallbladder
(20 – 40) (0.11) (0.025)
Rb-823 1100 – 1850 i.v. 0.018 0.0048
Kidneys
(30 – 50) (0.067) (0.018)
* See package insert for full prescribing information and complete radiation Dosimetrydosimetry.
1ICRP 53, page p. 373.

same day) are a total of 4 mCi of Tl-201, 40 mCi lution parallel-hole collimator, with the cam-
of Tc-99m–labeled radiopharmaceuticals, and era as close to the chest as possible. Images
120 mCi of Rb-82. When rest and stress studies should be acquired so that the heart occupies
are performed on separate days, the dose of thal- ~35%–50% of the usable field of view (using
lium may be 4 mCi/injection and the dose of the magnification during image acquisition if a
technetium-labeled agents may be 30 mCi/injec- large-field-of-view camera is employed to
tion. Doses may be adjusted at the discretion of record the data). Images of diagnostic quality
the prescribing physician. can be obtained if a minimum of 500,000
E. Image Acquisition: Single Photon counts are recorded in each view (a minimum
Data can be acquired using planar, SPECT, or a of 400 cts/cm2 of normal myocardium). The
combination of both techniques. SPECT imaging timing of imaging after injection of the radio-
is strongly preferred. pharmaceutical will vary with the radiophar-
1. Planar imaging maceutical (immediate images are required
Images are usually recorded with the patient for teboroxime, within minutes of injection for
supine on the imaging table in at least 3 stan- thallium, and 30–60 minutes for sestamibi and
dard views: anterior view, a left anterior tetrofosmin). Anatomic structures that may
oblique (LAO) view to optimize visualization attenuate myocardial activity (e.g., breast tis-
of the septum (usually 45°), and left lateral sue) should be positioned in identical fashion
view (preferably recorded with the patient in for the rest and stress studies.
the right lateral decubitus position to mini- 2. SPECT
mize attenuation from the abdomen). Image SPECT images can be recorded with either a
acquisition should commence as soon as the 180° or 360° collection, but a 180° acquisition
patient’s heart rate has recovered to near is preferred because of better resolution and
baseline values (preferably within 10 minutes contrast and less attenuation. Imaging with
of injection). Additional views may be re- Tl-201 should commence 5–10 minutes after
quired to account for unusual cardiac orienta- injection, as soon as the patient’s heart rate
tion within the thorax. Acquisition is per- has returned to near baseline levels, to maxi-
formed with a gamma camera equipped with mize the ability to detect transient left ventric-
either a low-energy all-purpose or high-reso- ular dysfunction. Imaging with Tc-99m ses-


tamibi or tetrofosmin should commence after heart activity ratio) and to evaluate the pat-
liver activity has sufficiently cleared, usually tern of myocardial perfusion in the event of
15–30 minutes after a stress injection and patient movement during SPECT acquisition.
45–60 minutes after a rest injection. The pa- Data may be recorded with attenuation
tient should be placed in a comfortable posi- correction, using either an x-ray or radionu-
tion on the SPECT table. The left arm should clide source. The attenuation correction infor-
be positioned away from the field of acquisi- mation reduces the influence of photon atten-
tion. Data are usually recorded with the pa- uation as a cause of decreased myocardial
tient in the supine position; however, in pa- activity. Although this approach is attractive,
tients likely to have significant diaphragmatic some available hardware and software result
(abdominal) attenuation, imaging in the in artifacts. As a result, both uncorrected and
prone or left lateral position may produce a corrected data should be reviewed to mini-
better result. To reduce artifacts from attenua- mize the likelihood of misinterpretation. At-
tion, a scintillation camera with attenuation tenuation correction methodology is still un-
correction hardware and software may be der development and evaluation.
used. Either a step-and-shoot acquisition with 3. PET
32 or 64 stops separated by 3–6° or continuous Positron images are generally corrected for at-
acquisition may be used. The duration of ac- tenuation. Because of the short physical half-
quisition at each stop varies with the protocol life of Rb-82 (~75 sec) and to minimize mis-
and radiopharmaceutical (generally 40 sec- alignment between emission and
onds/image for thallium and low-dose Tc- transmission images, pharmacologic stress is
99m sestamibi/tetrofosmin, and 25 sec- used in these patients. In many PET systems,
onds/image for high-dose Tc-99m the initial acquisition is performed as a
sestamibi/tetrofosmin). ECG gating for the “scout,” with 15–20 mCi Rb-82 to help posi-
acquisition of cardiac function should be used tioning and determine timing for start of im-
whenever possible (particularly when the age acquisition (longer delay in patients with
studies are recorded with Tc-99m radiophar- slow circulation times, usually as a result of
maceuticals) and may be accomplished with heart failure). The resting study can be per-
the placement of nonradiopaque electrodes formed first, because of the short half-life of
and a gating device. SPECT images are ac- Rb-82. Image acquisition usually begins 65–95
quired using a high-resolution collimator. seconds after the intravenous administration
Planar images may be acquired before the ini- of Rb-82 (longer times in patients with slow
tiation of SPECT acquisition to measure lung circulation times, indicated on the “scout” im-
radiopharmaceutical uptake (i.e., lung-to- ages) and continues for 5–10 minutes. Next,

Figure 1. Orientation for display of tomographic myocardial perfusion data.


the transmission images are recorded to ac- are evaluated for areas of decreased radiophar-
quire 30–40 million counts, beginning about maceutical concentration in the stress or rest im-
9–10 minutes after injection of rubidium for ages and for changes in regional count density
the “scout” scan. Finally, dipyridamole or when gated data are recorded. Zones of my-
adenosine is administered intravenously, fol- ocardium with tracer concentration below nor-
lowed by a Rb-82 injection and PET acquisi- mal with injection at rest are usually associated
tion during maximal pharmacological stress. with myocardial scar, but fixed defects with up-
The relative distribution of perfusion is evalu- take >50% of normal regions are often viable. De-
ated at rest, followed by evaluation at stress. fects seen at stress that improve on the resting
4. Image evaluation study usually indicate ischemia. Additional pa-
The study is initially reviewed for possible ar- rameters that are particularly useful on planar
tifacts, image processing problems, patient thallium images are increased lung uptake or left
motion, and overall image quality before vi- ventricular cavity dilatation as markers of severe
sual analysis or quantitative interpretation. left ventricular dysfunction.
Planar and SPECT images should be viewed 1. Viability
on a computer display to permit adjustment Tl-201 can be injected at rest to detect de-
of contrast and brightness, optimized to the creased perfusion to areas of viable my-
myocardium. Before reconstruction, the ocardium. Images recorded 10–15 minutes af-
SPECT projection data should be reviewed as ter injection (initial images) are compared
a cine display to detect patient motion. Signif- with those recorded at least 3–24 hours later.
icant patient motion during image acquisition An increase in the relative concentration of
may necessitate the reprocessing or reacquisi- tracer seen initially to that recorded later indi-
tion of these studies. Data should be recon- cates viable myocardium.
structed using either a filtered backprojection I. Reporting
or iterative reconstruction algorithm. The report should contain information about the
Perfusion PET images should be carefully indication for the study, condition of the patient
reviewed to detect cardiac displacement be- at the time of injection, the specific radiopharma-
tween rest and stress. ceutical, dose and route of administration, distri-
F. Interventions bution of radiopharmaceutical in the my-
Stress tests were described previously in this ocardium, relative size and shape of the left
guideline. ventricle, and, if a gated scan is performed, re-
G. Processing gional thickening of the myocardium and left
Approaches to data processing and study quality ventricular ejection fraction. The report should
control are described in the guideline on SPECT conclude with a concise impression.
imaging (see Society of Nuclear Medicine Proce- Information about the condition of the pa-
dure Guideline for General Imaging). After re- tient at the time of injection should include: the
construction, the myocardial perfusion images type of stress (e.g., treadmill, bicycle), exercise
can be analyzed for the relative activity in each level achieved (preferably expressed in mets),
section of myocardium. That result can be com- heart rate, blood pressure, symptoms, and a brief
pared with a normal database. Before quantify- description of the ECG at rest and changes in-
ing the data, the images should be reviewed for duced by stress. The duration of exercise should
artifacts resulting from attenuation or zones of also be stated. With pharmacologic stress, the
unexpected increased activity. In the absence of type and dose of drug and duration of infusion
artifacts, the zones of myocardium for quantifi- should be noted, in addition to the changes in
cation are selected, the myocardial borders are heart rate, blood pressure, ECG, and symptoms.
defined, and the programs then calculate and Information about the distribution of radio-
display the relative distribution of activity. As pharmaceutical should include the site and ex-
with other forms of quantitation, this data is use- tent of reduced perfusion, likely vascular terri-
ful to supplement the interpretation of an experi- tory, and relationship of regional wall thickening
enced observer. to abnormal perfusion.
H. Interpretation Criteria J. Quality Control
Before interpreting the images, the data should (See Society of Nuclear Medicine Procedure
be reviewed for artifacts resulting from attenua- Guideline on General Imaging.)
tion or zones of unexpected increased activity K. Sources of Error
that may alter the appearance of the my- 1. Radiopharmaceutical dose delivery
ocardium. In the absence of artifacts, the images Interstitial (nonintravenous) injection of the


radiopharmaceutical as a result of a malfunc- ous studies easier. Prior studies should be re-
tioning intravenous catheter will reduce de- viewed for comparison to the current study to
livery of the radiopharmaceutical to the my- note differences (i.e., new findings).
ocardium and alter radiopharmaceutical 7. Noncomparability of views/tomographic
uptake and clearance kinetics. A low count slices
image should raise concern regarding ade- Comparable views and tomographic slices
quate delivery of the radiopharmaceutical should be displayed for comparison of the
and prompt imaging of the injection site for rest and stress (or redistribution) data.
confirmation of the infiltrated dose. 8. Review of raw data
2. Patient motion Before examination of reconstructed tomo-
Voluntary or involuntary patient motion dur- graphic cuts, the raw tomographic data acqui-
ing image acquisition will create image blur- sition should be reviewed in a rotational cine-
ring and artifacts that may appear as irregu- matic format for the presence of attenuation
larities or zones of decreased uptake in the artifacts and zones of increased activity (e.g.,
myocardium. Careful attention to patient lung, liver, bowel, or renal activity and other
comfort and stability during the acquisition lesions) that may alter the appearance of the
may prevent major motion artifacts. Minor myocardium on the reconstructed data. If
motion artifacts often can be corrected by re- possible, steps should be taken to compensate
processing of data, using a motion-correction for these problems, or the acquisition may
algorithm. Patients should not be released be- have to be repeated.
fore review of raw data for patient motion. 9. Region of interest placement
3. Suboptimal stress level For quantitative analysis of regional myocar-
Failure to achieve the gender- and age-pre- dial and lung activity, it is necessary to assure
dicted 85% peak maximal heart rate will re- that regions of interest do not include activity
duce the sensitivity of this procedure for de- from adjacent structures. Calculation of the
tection of CAD. Patients who cannot achieve lung-to-heart activity ratio should include a
85% of maximal predicted heart rate should similarly sized region of interest in lung and
be considered for pharmacologic stress before myocardium, not including the anterior and
stress injection. Concomitant medications that anterolateral wall, where lung and my-
attenuate or block the action of pharmaco- ocardium activity overlap. Attempts should
logic stress agents may have a similar effect. be made to include only cardiac activity in re-
4. Inappropriate image processing gions of interest utilized for quantitative anal-
Inappropriate filtering of raw backprojected ysis of radiopharmaceutical uptake and clear-
tomographic data may significantly degrade ance.
image quality. Recommended filters and cut- 10. Compatibility with normal database
off limits should be applied to the processing For quantitative analysis, the SPECT data
of tomographic myocardial perfusion data. must be processed in an identical fashion to
Inappropriate count normalization of stress the normal data file, including filtering, reori-
and rest images may cause noncomparability entation, and quantitative analysis.
of images for diagnostic analysis.
5. Attenuation artifacts
VI. Issues Requiring Further Clarification
Failure to recognize and account for the pres-
ence of soft tissue attenuation (often in breast, None
obesity, abdominal structures, etc.) can ham-
per accurate image analysis by creating false-
I. Concise Bibliography
positive lesions on the rest and/or stress im-
ages. Prone imaging or the use of American Society of Nuclear Cardiology. Imaging
attenuation-correction hardware and soft- guidelines for nuclear cardiology procedures, part
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Society of Nuclear Medicine–approved American Society of Nuclear Cardiology. Imaging
nomenclature should be used to describe guidelines for nuclear cardiology procedures, part
anatomic areas in each of the 3 reconstructed 2. Myocardial perfusion stress protocols. J Nucl Car-
orthogonal tomographic views and on each of diol. 1999;6(2):G47–84.
the 3 planar images to avoid diagnostic incon- Cardiovascular Imaging Committee, American College
sistencies and render comparisons to previ- of Cardiology. Standardization of cardiac tomo-


graphic imaging. J Am Coll Cardiol. 1992;20:255–256. VIII. Disclaimer
Committee on Advanced Cardiac Imaging and Tech-
The Society of Nuclear Medicine has written and ap-
nology, Council of Clinical Cardiology, American
proved guidelines to promote the cost-effective use
Heart Association, Cardiovascular Imaging Com-
of high quality nuclear medicine procedures. These
mittee, American College of Cardiology, and the
generic recommendations cannot be applied to all
Board of Directors of the Cardiovascular Commit-
patients in all practice settings. The guidelines
tee, Society of Nuclear Medicine. Standardization
should not be deemed inclusive of all proper proce-
of cardiac tomographic imaging. J Nucl Med.
dures or exclusive of other procedures reasonably
1992;33:1434–1435.
directed to obtaining the same results. The spectrum
Ritchie J, Bateman TM, Bonow RO, et al. Guidelines for
of patients seen in a specialized practice setting may
clinical use of cardiac radionuclide imaging. A re-
be quite different than the spectrum of patients seen
port of the AHA/ACC Task Force on Assessment of
in a more general practice setting. The appropriate-
Diagnostic and Therapeutic Cardiovascular Proce-
ness of a procedure will depend in part on the preva-
dures, Committee on Radionuclide Imaging, devel-
lence of disease in the patient population. In addi-
oped in collaboration with the American Society of
tion, the resources available to care for patients may
Nuclear Cardiology. Circulation. 1995;91:1278–1303.
vary greatly from one medical facility to another. For
Schlant RC, Friesinger GC, Leonard JJ. Clinical compe -
these reasons, guidelines cannot be rigidly applied.
tence in exercise testing. A statement for physicians
from the ACP/ACC/AHA Task Force on Clinical Advances in medicine occur at a rapid rate. The
Privileges in Cardiology. J Am Coll Cardiol. date of a guideline should always be considered in
1990;16:1061–1065. determining its current applicability.
Updated imaging guidelines for nuclear cardiology
procedures, part 1. J Nucl Cardiol. 2001;8(1):G5–G58.

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