Ischemic Heart Disease, Myocardial Infarction
Conditions
Keywords
SPECT MPI, Tomography, Emission-Computed, Single-Photon, Wide Beam Reconstruction
Brief summary
This study is recruiting patients already scheduled for a single photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) test. SPECT-MPI is a nuclear imaging technique that uses a radioactive substance, or radiotracer, and special equipment to create three-dimensional (3D) images of the heart. Radiotracer is a radioactive dye that will make the structures of the heart visible and is routinely used to view blood flow in the heart, scan for damaged heart tissue, or assess heart function. For a routine SPECT-MPI test, the radiotracer is given in one dose at the beginning of the test, followed by taking resting images of the heart. For this study, researchers would like to administer half of the radiotracer, obtain resting images, administer the remainder of the radiotracer and obtain a second set of resting images. Participants will receive the same amount of radioactive material that would normally be given for this test; however, it will be administered in two half-doses. Participation in this study will add about 30 minutes to the time it takes to complete the routine test. The investigators expect to enroll about 160 subjects in this study at Northwestern.
Detailed description
Subjects in this study will proceed to the nuclear cardiology laboratory for their scheduled nuclear stress test. After informed consent is obtained, the study doctor or research staff member will ask detailed questions about the subject's current health, medications and medical history, and the subject's medical chart will be reviewed including results of any previous nuclear images. For the test, a small catheter (tube) will be placed in a vein in the subject's arm to administer the radioactive imaging agent, Tc-99m sestamibi. Subjects will be given half (1/2) of the normal Tc-99m sestamibi dose and then the study staff will obtain resting images pictures of the heart. After this set of images, the subject will be given the remaining half of the radioactive imaging agent followed by a second set of images. After this, the subject will then undergo the stress portion of the test in the usual manner as prescribed by the referring physician.
Interventions
DRUGHalf-dose of the Tc99-m sestamibi (Cardiolite)
Researchers will administer half of the radiotracer (Cardiolite), obtain resting images, administer the remainder of the radiotracer and obtain a second set of resting images. Subjects will be given the same amount of radioactive material that would normally be given for this test; however, it will be administered in two ½ doses.
Sponsors
Astellas Pharma Global Development, Inc.
Edwin Wu
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients over the age of 18 years * Undergoing nuclear stress testing * History of myocardial infarction, cardiomyopathy, heart failure or prior nuclear studies with resting perfusion defects
Exclusion criteria
* Unwilling or unable to undergo an additional resting SPECT acquisition * Clinical contraindications to nuclear stress testing including acute myocardial infarction * For patients undergoing exercise treadmill stress testing: * Left bundle branch block or artificial ventricular pacemaker * For patients undergoing regadenoson (Lexiscan) stress testing: * Moderate to severe chronic obstructive pulmonary disease or asthma, second- or third degree atrioventricular block or sinus node disease (unless patients have a functioning artificial pacemaker), known hypersensitivity to aminophylline or adenosine * Inability to give informed consent
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Sum Rest Score | Baseline | Left ventricular myocardium was divided into standardized 17-segments with 6 equiangular segments in the basal region, 6 equiangular segments in the mid region, 4 equiangular segments in the apical regions, and 1 region in the apex (Cerqueira MD, et al., J Nucl Cardiol 2002;9:240-5). Each segment was scored on a scale from 0 to 4 to indicate the severity of the perfusion defect (0=no perfusion defect; 1=mild perfusion defect; 2=moderate perfusion defect; 3=severe perfusion defect; and 4=absent perfusion). The scores over 17 segments were summed to report the Sum Rest Score (SRS), ie. the greater the SRS, the larger the perfusion defect. |
| Segments With Resting Perfusion Defect | Baseline | Left ventricular myocardium was divided into standardized 17-segments with 6 equiangular segments in the basal region, 6 equiangular segments in the mid region, 4 equiangular segments in the apical regions, and 1 region in the apex (Cerqueira MD, et al., J Nucl Cardiol 2002;9:240-5). Each segment was scored on a scale from 0 to 4 to indicate the severity of the perfusion defect (0=no perfusion defect; 1=mild perfusion defect; 2=moderate perfusion defect; 3=severe perfusion defect; and 4=absent perfusion). The number of segments with a score of 1 or greater were summed to obtain the number of segments with a resting perfusion defect. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Image Quality Score | Baseline | Each reconstructed image was subjectively scored by the expert readers to determine the overall image quality. The Image Quality Score of the reconstructed images were graded on a 4-point scale. (1=Poor; 2=Fair; 3=Good; and 4=Excellent). |
| Diagnostic Confidence Score | Baseline | Each reconstructed image was subjectively scored by the expert readers to determine the expert reader's diagnostic confidence in scoring and interpreting the perfusion scores. The Diagnostic Confidence Score of the reconstructed images were graded on a 4-point scale. (1=Poor; 2=Fair; 3=Good; and 4=Excellent). |
Countries
United States
Participant flow
Recruitment details
Prospectively enroll patients with history of severe myocardial infarction, cardiomyopathy, heart failure or prior nuclear scans with resting perfusion defects. Patients were approached in the nuclear stress lab prior to scheduled stress test. Recruitment period was between 3/20/2012 and 2/14/2014.
Participants by arm
| Arm | Count |
|---|---|
| Study Group Entire cohort | 64 |
| Total | 64 |
Baseline characteristics
| Characteristic | Study Group |
|---|---|
| Age, Continuous | 66 years STANDARD_DEVIATION 11 |
| Body mass index | 30.2 kg/m^2 STANDARD_DEVIATION 6 |
| Height | 68.0 inches STANDARD_DEVIATION 4.1 |
| History Coronary artery bypass surgery | 27 participants |
| History Coronary artery disease | 46 participants |
| History Diabetes mellitus | 21 participants |
| History Family history of CAD | 19 participants |
| History Hypercholesterolemia | 52 participants |
| History Hypertension | 58 participants |
| History Prior Myocardial Infarct | 28 participants |
| History Tobacco smoking (prior or current) | 24 participants |
| Indications for stress test Cardiomyopathy | 5 participants |
| Indications for stress test Chest pain | 16 participants |
| Indications for stress test CHF | 6 participants |
| Indications for stress test Dyspnea | 9 participants |
| Indications for stress test Other | 9 participants |
| Indications for stress test Prior CABG | 8 participants |
| Indications for stress test Prior Coronary Disease | 18 participants |
| Indications for stress test Prior Myocardial Infarct | 7 participants |
| Indications for stress test Prior PCI | 5 participants |
| Medications ACE inhibitors/ARB | 33 participants |
| Medications Anti-platelet | 21 participants |
| Medications Aspirin | 51 participants |
| Medications Beta-blockers | 56 participants |
| Medications Ca-channel blockers | 19 participants |
| Medications Diuretic | 24 participants |
| Medications Nitrates | 11 participants |
| Medications Statin | 53 participants |
| Previous nuclear stress | 39 participants |
| Sex: Female, Male Female | 16 Participants |
| Sex: Female, Male Male | 48 Participants |
| Weight | 198.4 pounds STANDARD_DEVIATION 40 |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 64 |
| serious Total, serious adverse events | 0 / 64 |
Outcome results
Primary
Segments With Resting Perfusion Defect
Left ventricular myocardium was divided into standardized 17-segments with 6 equiangular segments in the basal region, 6 equiangular segments in the mid region, 4 equiangular segments in the apical regions, and 1 region in the apex (Cerqueira MD, et al., J Nucl Cardiol 2002;9:240-5). Each segment was scored on a scale from 0 to 4 to indicate the severity of the perfusion defect (0=no perfusion defect; 1=mild perfusion defect; 2=moderate perfusion defect; 3=severe perfusion defect; and 4=absent perfusion). The number of segments with a score of 1 or greater were summed to obtain the number of segments with a resting perfusion defect.
Time frame: Baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Half-dose WBR | Segments With Resting Perfusion Defect | 4.6 segments | Standard Deviation 2.4 |
| Half-dose FBP | Segments With Resting Perfusion Defect | 4.0 segments | Standard Deviation 2.2 |
| Full-dose FBP | Segments With Resting Perfusion Defect | 3.8 segments | Standard Deviation 2.6 |
p-value: 0.006Wilcoxon (Mann-Whitney)
p-value: 0.44Wilcoxon (Mann-Whitney)
Primary
Sum Rest Score
Left ventricular myocardium was divided into standardized 17-segments with 6 equiangular segments in the basal region, 6 equiangular segments in the mid region, 4 equiangular segments in the apical regions, and 1 region in the apex (Cerqueira MD, et al., J Nucl Cardiol 2002;9:240-5). Each segment was scored on a scale from 0 to 4 to indicate the severity of the perfusion defect (0=no perfusion defect; 1=mild perfusion defect; 2=moderate perfusion defect; 3=severe perfusion defect; and 4=absent perfusion). The scores over 17 segments were summed to report the Sum Rest Score (SRS), ie. the greater the SRS, the larger the perfusion defect.
Time frame: Baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Half-dose WBR | Sum Rest Score | 8.1 units on a scale | Standard Deviation 5.9 |
| Half-dose FBP | Sum Rest Score | 6.7 units on a scale | Standard Deviation 5.1 |
| Full-dose FBP | Sum Rest Score | 6.5 units on a scale | Standard Deviation 6.1 |
p-value: 0.001Wilcoxon (Mann-Whitney)
p-value: 0.67Wilcoxon (Mann-Whitney)
Secondary
Diagnostic Confidence Score
Each reconstructed image was subjectively scored by the expert readers to determine the expert reader's diagnostic confidence in scoring and interpreting the perfusion scores. The Diagnostic Confidence Score of the reconstructed images were graded on a 4-point scale. (1=Poor; 2=Fair; 3=Good; and 4=Excellent).
Time frame: Baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Half-dose WBR | Diagnostic Confidence Score | 2.5 units on a scale | Standard Deviation 0.8 |
| Half-dose FBP | Diagnostic Confidence Score | 2.7 units on a scale | Standard Deviation 0.9 |
| Full-dose FBP | Diagnostic Confidence Score | 3.0 units on a scale | Standard Deviation 0.8 |
p-value: <0.001Wilcoxon (Mann-Whitney)
p-value: 0.08Wilcoxon (Mann-Whitney)
Secondary
Image Quality Score
Each reconstructed image was subjectively scored by the expert readers to determine the overall image quality. The Image Quality Score of the reconstructed images were graded on a 4-point scale. (1=Poor; 2=Fair; 3=Good; and 4=Excellent).
Time frame: Baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Half-dose WBR | Image Quality Score | 2.3 units on a scale | Standard Deviation 0.8 |
| Half-dose FBP | Image Quality Score | 2.6 units on a scale | Standard Deviation 0.6 |
| Full-dose FBP | Image Quality Score | 3.0 units on a scale | Standard Deviation 0.7 |
p-value: <0.001Wilcoxon (Mann-Whitney)
p-value: 0.002Wilcoxon (Mann-Whitney)
Post Hoc
Injection and Scan Times
Time in minutes between doses of resting Tc-99m sestamibi doses and image scanning.
Time frame: Baseline
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Half-dose WBR | Injection and Scan Times | 30.0 minutes | Standard Deviation 5.4 |
| Half-dose FBP | Injection and Scan Times | 33.1 minutes | Standard Deviation 13.1 |
| Full-dose FBP | Injection and Scan Times | 56.7 minutes | Standard Deviation 8.2 |
Post Hoc
Resting Full-Tracer Dose
Amount of the standard, clinically-accepted, full-dose Tc-99m sestamibi dose administered
Time frame: Baseline
Population: Entire Cohort
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Half-dose WBR | Resting Full-Tracer Dose | 9.08 millicurie | Standard Deviation 0.46 |