Rapid Stress/Rest Single-Day Tc-99m Sestamibi Myocardial Single Photon Emission Computed Tomography
| Status: | Completed |
|---|---|
| Conditions: | Peripheral Vascular Disease, Cardiology |
| Therapuetic Areas: | Cardiology / Vascular Diseases |
| Healthy: | No |
| Age Range: | 18 - Any |
| Updated: | 4/21/2016 |
| Start Date: | July 2011 |
| End Date: | March 2012 |
Rapid Stress/Rest Single-Day Tc-99m Sestamibi Myocardial SPECT
This protocol details a novel myocardial perfusion Single Photon Emission Computed
Tomography (SPECT) protocol wherein patients receive a low-dose (6 mCi) of Tc-99m sestamibi
during exercise or regadenoson pharmacologic stress and undergo a full-time SPECT
acquisition processed with Wide Beam Reconstruction (WBR). Immediately thereafter patients
receive a high-dose (30-35 mCi) of Tc-99m sestamibi at rest and undergo a half-time rest
scan, also processed with WBR. All enrolled research subjects will undergo both the initial
stress and subsequent rest scan.
The radiation exposure associated with this new stress/rest protocol is equivalent to that
of the conventional rest/stress protocol presently in routine clinical uses at SLRHC.
Eventually, when and if this novel stress/rest protocol is adopted in routine clinical
practice, patients with normal stress scans would receive only 6 mCi of Tc-99m sestamibi
(331 mSv in men, 241 mSv in women) and spend only approximately one hour in the Nuclear
Medicine Laboratory.
All patients presenting to the Nuclear Medicine Laboratory for evaluation of known or
suspected coronary artery disease will be candidates for enrollment. Fifty patients
undergoing treadmill exercise stress and 50 patients undergoing regadenoson pharmacologic
stress will be enrolled. Pregnant and breast-feeding patients will not be eligible.
Tomography (SPECT) protocol wherein patients receive a low-dose (6 mCi) of Tc-99m sestamibi
during exercise or regadenoson pharmacologic stress and undergo a full-time SPECT
acquisition processed with Wide Beam Reconstruction (WBR). Immediately thereafter patients
receive a high-dose (30-35 mCi) of Tc-99m sestamibi at rest and undergo a half-time rest
scan, also processed with WBR. All enrolled research subjects will undergo both the initial
stress and subsequent rest scan.
The radiation exposure associated with this new stress/rest protocol is equivalent to that
of the conventional rest/stress protocol presently in routine clinical uses at SLRHC.
Eventually, when and if this novel stress/rest protocol is adopted in routine clinical
practice, patients with normal stress scans would receive only 6 mCi of Tc-99m sestamibi
(331 mSv in men, 241 mSv in women) and spend only approximately one hour in the Nuclear
Medicine Laboratory.
All patients presenting to the Nuclear Medicine Laboratory for evaluation of known or
suspected coronary artery disease will be candidates for enrollment. Fifty patients
undergoing treadmill exercise stress and 50 patients undergoing regadenoson pharmacologic
stress will be enrolled. Pregnant and breast-feeding patients will not be eligible.
Specific Aims:
To validate acceptable image quality and the stress/rest myocardial count density ratio (as
defined below) of the Rapid Stress/Rest Protocol
Experimental Design and Methods:
Validation of the stress/rest myocardial count density ratio achieved using a standard
rest/stress protocol incorporating a conventional 3:1 stress/rest Tc-99m radiopharmaceutical
dose ratio.
Human subjects:
To determine the stress/rest myocardial count density ratio encountered using existing
rest/stress imaging protocols in routine clinical practice, 100 consecutive patients
undergoing either exercise or pharmacologic stress (dipyridamole or regadenoson) myocardial
perfusion SPECT were included. The stress/rest Tc-99m sestamibi/Tc-99m tetrofosmin
radiopharmaceutical dose ratio was 3:1 in all patients. Stress and rest maximal myocardial
counts were determined from reconstructed tomograms using Evolution software (GE
Healthcare).
The Investigational, novel stress/rest protocol:
Human Subjects: Characteristics and Plans for Recruitment 100 patients, who give their
consent, presenting for myocardial perfusion SPECT in whom exercise or pharmacologic stress
is clinically indicated will be enrolled prospectively. There will be no bias in selection
of patients with regard to gender or racial/ethnic composition. 50 patients will be stressed
with exercise. 50 additional patients will receive pharmacologic stress with the on-label
dose of Regadenoson. All patients will receive the appropriate dose of radiotracer according
to their size and weight. Pregnant women and those who are breast feeding will not be
enrolled.
Patient Informed Consent:
Written informed consent will be obtained by either the Principal Investigator, the PI's
research assistant (a physician), a Nuclear Medicine resident, or a Cardiology fellow (who
will supervise and monitor the stress testing).
Methods - Imaging and Data Analysis:
The rapid stress/rest protocol, as described above, will be performed using the GE Ventri,
MG or Maxxus dual-head supine scintillation camera and UltraSPECT Wide Beam Reconstruction
(WBR) software. Both stress and rest SPECT will be performed in all patients, even if the
initial stress images are normal.
Images will be interpreted and reported in the standard fashion for clinical patient
management, characterizing perfusion defects in terms of location, extent, severity,
reversibility, and function in terms of volume, regional wall motion and wall thickening.
Patient flow:
1. Upon arrival in the Nuclear Medicine Laboratory, patients will be interviewed regarding
their medical history and a limited physical examination will be performed (as
routinely performed for all clinically-indicated myocardial perfusion scans), and
informed consent will be obtained for enrollment in this research study.
2. Patients able to perform treadmill exercise to 85% of their age-predicted maximum heart
rate will undergo treadmill exercise stress. In the remainder of patients pharmacologic
stress will be achieved with intravenous regadenoson. A stress dose of 5-7 mCi
(adjusted for patient weight and chest circumference) Tc-99m sestamibi will be
administered intravenously.
3. Post-stress gated SPECT will be acquired 30-60 min. thereafter using a full-time stress
(12 min.) acquisition protocol, and processed using "half-time" Wide Beam
Reconstruction software (i.e."half-dose" WBR protocol).
4. Within 60 minutes thereafter patients will receive an additional intravenous dose of
35-42 mCi (adjusted for patient weight and chest circumference) Tc-99m sestamibi at
rest.
5. Resting gated SPECT will be acquired 40-60 minutes thereafter using a half-time resting
(7.5 min.) acquisition protocol, and processed using "half-time" Wide Beam
Reconstruction software (i.e. half-time" WBR protocol).
6. The estimated time for the entire study is approximately 3 hrs, which is slightly less
than the time fro the standard rest/stress protocol the investigators now use.
Scans will be assessed for image quality using a 5-point subjective scale used in several
reports the investigators have published previously (in references #2 and #3 below):
The image quality of the stress and rest perfusion tomograms and the gated tomograms is
graded visually using a 5-point scale: 1 (poor) - 5 (excellent). Myocardial count density
and uniformity, endocardial and epicardial edge definition, visualization and definition of
the right ventricle, and background noise are parameters considered subjectively when
grading image quality. In addition to those same attributes considered when grading the
summed perfusion tomograms, the definition of the left ventricular cavity at end-systole and
the temporal smoothness of the gated frames are also considered when grading the post-stress
and rest gated images.
Stress and rest absolute myocardial count density and the stress:rest myocardial count
density ratio will be determined from processed tomograms using General Electric Xeleris
computer software. Count density is basically the "information density" of the scan. In
general, as for all of nuclear imaging, the higher the count density, the better the image
quality, the lower the incidence of scan artifacts, and the greater the clinical value of
the scan.
The rest/stress myocardial count density ratio achieved using the novel low-dose
stress/high-dose rest protocol will be compared to the stress/rest ratios achieved using
conventional rest/stress protocols (described above). The unpaired Student's t-test will be
used. In addition rest/stress count densities achieved using exercise (50 patients) and
regadenoson (50 patients) with the novel protocol will be compared with stress/rest ratios
achieved using standard rest/stress imaging in the exercise (59 patients) and regadenoson
(29 patients) subgroups.
Primary Endpoint 1: Comparison of the myocardial count density ratio of the test group using
the Rapid Protocol vs. the myocardial count density ratio of the Traditional protocol in the
control group.
Secondary Endpoints
1. Image quality
2. # of patients with normal stress studies that may have had a stress-only study.
3. Reduction in radiation exposure between Test (Rapid) and Control (Traditional) groups
4. Comparison of absolute stress and rest myocardial count densities in Test and Control
groups 5. Start to finish time, and potential cost savings between the two groups 6.
Comparison of total radiopharmaceutical dose between the two groups
Study Duration:
1 year
Statistical Plan:
Primary endpoint: The individual stress and rest, as well as the stress:rest myocardial
count density ratio will be determined from test group processed tomograms and compared with
control group using UNPAIRED T TEST
Secondary: The image quality of the test group stress and rest perfusion tomograms and the
gated tomograms will be graded visually using a 5-point scale: 1 (poor) - 5 (excellent), and
compared with the control group using the UNPAIRED T TEST.
The overall reduction in radiation exposure to the test group will be analyzed using, as a
comparator, the patient size and weight based radiopharmaceutical dose and imaging time used
in a standard Stress/Rest Protocol.
The time and cost savings associated with forgoing the resting study in those patients with
a normal stress scan will be calculated.
Based on a control group mean maximum contrast dose (MCD) of 4.4 and standard deviation of
9.5, this study will have greater than 80% power to detect a 0.3 difference in the MCD
ratio. (Alpha=5%)
To validate acceptable image quality and the stress/rest myocardial count density ratio (as
defined below) of the Rapid Stress/Rest Protocol
Experimental Design and Methods:
Validation of the stress/rest myocardial count density ratio achieved using a standard
rest/stress protocol incorporating a conventional 3:1 stress/rest Tc-99m radiopharmaceutical
dose ratio.
Human subjects:
To determine the stress/rest myocardial count density ratio encountered using existing
rest/stress imaging protocols in routine clinical practice, 100 consecutive patients
undergoing either exercise or pharmacologic stress (dipyridamole or regadenoson) myocardial
perfusion SPECT were included. The stress/rest Tc-99m sestamibi/Tc-99m tetrofosmin
radiopharmaceutical dose ratio was 3:1 in all patients. Stress and rest maximal myocardial
counts were determined from reconstructed tomograms using Evolution software (GE
Healthcare).
The Investigational, novel stress/rest protocol:
Human Subjects: Characteristics and Plans for Recruitment 100 patients, who give their
consent, presenting for myocardial perfusion SPECT in whom exercise or pharmacologic stress
is clinically indicated will be enrolled prospectively. There will be no bias in selection
of patients with regard to gender or racial/ethnic composition. 50 patients will be stressed
with exercise. 50 additional patients will receive pharmacologic stress with the on-label
dose of Regadenoson. All patients will receive the appropriate dose of radiotracer according
to their size and weight. Pregnant women and those who are breast feeding will not be
enrolled.
Patient Informed Consent:
Written informed consent will be obtained by either the Principal Investigator, the PI's
research assistant (a physician), a Nuclear Medicine resident, or a Cardiology fellow (who
will supervise and monitor the stress testing).
Methods - Imaging and Data Analysis:
The rapid stress/rest protocol, as described above, will be performed using the GE Ventri,
MG or Maxxus dual-head supine scintillation camera and UltraSPECT Wide Beam Reconstruction
(WBR) software. Both stress and rest SPECT will be performed in all patients, even if the
initial stress images are normal.
Images will be interpreted and reported in the standard fashion for clinical patient
management, characterizing perfusion defects in terms of location, extent, severity,
reversibility, and function in terms of volume, regional wall motion and wall thickening.
Patient flow:
1. Upon arrival in the Nuclear Medicine Laboratory, patients will be interviewed regarding
their medical history and a limited physical examination will be performed (as
routinely performed for all clinically-indicated myocardial perfusion scans), and
informed consent will be obtained for enrollment in this research study.
2. Patients able to perform treadmill exercise to 85% of their age-predicted maximum heart
rate will undergo treadmill exercise stress. In the remainder of patients pharmacologic
stress will be achieved with intravenous regadenoson. A stress dose of 5-7 mCi
(adjusted for patient weight and chest circumference) Tc-99m sestamibi will be
administered intravenously.
3. Post-stress gated SPECT will be acquired 30-60 min. thereafter using a full-time stress
(12 min.) acquisition protocol, and processed using "half-time" Wide Beam
Reconstruction software (i.e."half-dose" WBR protocol).
4. Within 60 minutes thereafter patients will receive an additional intravenous dose of
35-42 mCi (adjusted for patient weight and chest circumference) Tc-99m sestamibi at
rest.
5. Resting gated SPECT will be acquired 40-60 minutes thereafter using a half-time resting
(7.5 min.) acquisition protocol, and processed using "half-time" Wide Beam
Reconstruction software (i.e. half-time" WBR protocol).
6. The estimated time for the entire study is approximately 3 hrs, which is slightly less
than the time fro the standard rest/stress protocol the investigators now use.
Scans will be assessed for image quality using a 5-point subjective scale used in several
reports the investigators have published previously (in references #2 and #3 below):
The image quality of the stress and rest perfusion tomograms and the gated tomograms is
graded visually using a 5-point scale: 1 (poor) - 5 (excellent). Myocardial count density
and uniformity, endocardial and epicardial edge definition, visualization and definition of
the right ventricle, and background noise are parameters considered subjectively when
grading image quality. In addition to those same attributes considered when grading the
summed perfusion tomograms, the definition of the left ventricular cavity at end-systole and
the temporal smoothness of the gated frames are also considered when grading the post-stress
and rest gated images.
Stress and rest absolute myocardial count density and the stress:rest myocardial count
density ratio will be determined from processed tomograms using General Electric Xeleris
computer software. Count density is basically the "information density" of the scan. In
general, as for all of nuclear imaging, the higher the count density, the better the image
quality, the lower the incidence of scan artifacts, and the greater the clinical value of
the scan.
The rest/stress myocardial count density ratio achieved using the novel low-dose
stress/high-dose rest protocol will be compared to the stress/rest ratios achieved using
conventional rest/stress protocols (described above). The unpaired Student's t-test will be
used. In addition rest/stress count densities achieved using exercise (50 patients) and
regadenoson (50 patients) with the novel protocol will be compared with stress/rest ratios
achieved using standard rest/stress imaging in the exercise (59 patients) and regadenoson
(29 patients) subgroups.
Primary Endpoint 1: Comparison of the myocardial count density ratio of the test group using
the Rapid Protocol vs. the myocardial count density ratio of the Traditional protocol in the
control group.
Secondary Endpoints
1. Image quality
2. # of patients with normal stress studies that may have had a stress-only study.
3. Reduction in radiation exposure between Test (Rapid) and Control (Traditional) groups
4. Comparison of absolute stress and rest myocardial count densities in Test and Control
groups 5. Start to finish time, and potential cost savings between the two groups 6.
Comparison of total radiopharmaceutical dose between the two groups
Study Duration:
1 year
Statistical Plan:
Primary endpoint: The individual stress and rest, as well as the stress:rest myocardial
count density ratio will be determined from test group processed tomograms and compared with
control group using UNPAIRED T TEST
Secondary: The image quality of the test group stress and rest perfusion tomograms and the
gated tomograms will be graded visually using a 5-point scale: 1 (poor) - 5 (excellent), and
compared with the control group using the UNPAIRED T TEST.
The overall reduction in radiation exposure to the test group will be analyzed using, as a
comparator, the patient size and weight based radiopharmaceutical dose and imaging time used
in a standard Stress/Rest Protocol.
The time and cost savings associated with forgoing the resting study in those patients with
a normal stress scan will be calculated.
Based on a control group mean maximum contrast dose (MCD) of 4.4 and standard deviation of
9.5, this study will have greater than 80% power to detect a 0.3 difference in the MCD
ratio. (Alpha=5%)
Inclusion Criteria:
- adult
- not pregnant
- suspected coronary artery disease
Exclusion Criteria:
- pregnant
- under 18 years of age
We found this trial at
1
site
Click here to add this to my saved trials
