Article Figures & Data
Figures
- FIGURE 1.
Principle of ECG-gated acquisition. R–R interval on ECG, representing 1 cardiac cycle, is typically divided into 8 frames of equal duration (A). Image data from each frame are acquired over multiple cardiac cycles and stored separately in specific locations (“bin”) of computer memory (B). When all data in a bin are added together, image represents a specific phase of cardiac cycle. Typically, a volume curve is obtained, which represents endocardial volume for each of 8 frames (C). ED = end-diastole; ES = end-systole.
- FIGURE 2.
Same-day GSPECT protocols with 99mTc-sestamibi or 99mTc-tetrofosmin. Myocardial perfusion imaging can be gated either at rest or after exercise–stress in stress–rest (A) or rest–stress (B) sequence.
- FIGURE 3.
Assessment of LV regional function by GSPECT. RWM is assessed by inward excursion of endocardial wall (A) and SWT is assessed by myocardial brightening (arrow) from end-diastole to end-systole (B). ED = end-diastole; ES = end-systole; SEPT = septal; ANT = anterior; LAT = lateral.
- FIGURE 4.
Comparison of LVEF between GSPECT and contrast left ventrioculography (LVG) in a patient. ISE = base; ANT = anterior; SEPT = septal; INF = inferior.
- FIGURE 5.
GSPECT shows preserved SWT of anterior wall of LV, suggesting presence of attenuation artifact rather than true infarct.
Tables
Parameter Characteristic γ-Camera Dual or triple detector Collimator Low energy, high resolution Orbit 180° (dual detector) or 360° (triple detector) Projections 32∼64 Acquisition time/projection >25 s Matrix 64 × 64 Framing 8∼16/R–R interval Beat acceptance ±20% Total acquisition time ∼20–30 min Reference Parameter No. of patients Measurement Agreement Year Author 1997 Johnson et al. (23) LVEF 15 Consecutive days r = 0.98, SD = 2.6% 1998 Berman et al. (24) LVEF 180 Prone r = 0.93, SD = 3.2% EDV 180 Supine r = 0.97, SD = 2.6 mL ESV 180 Same-day consecutive scans r = 0.98, SD = 4.8 mL 2001 Paeng et al. (25) RWM 31 Same-day consecutive scans r = 0.95 (quantitative); 79%*, κ = 0.81 (visual) SWT 31 Same-day consecutive scans r = 0.88 (quantitative); 71%*, κ = 0.71 (visual) ↵* Exact segmental agreement.
κ = Cohen’s κ.
Measurements were performed using QGS software (18,19).
Reference Study patients No. of patients Modality of comparison r with GSPECT measurements Year Author EDV ESV LVEF 1999 Vaduganathan et al. (26) Recent MI 25 MRI 0.81 0.92 0.93 1999 Tadamura et al. (27) CAD 20 MRI 0.92 0.97 0.94 2000 Bavelaar-Croon et al. (28) CAD 21 MRI 0.94 0.95 0.85 2000 Bax et al. (29) CAD with LV dysfunction 25 MRI 0.84 0.87 0.90 1998 Nichols et al. (30) CAD 58 LVG 0.87 0.91 0.86 1999 Yoshioka et al. (31) Mixed 21 LVG 0.73 0.83 0.87 1999 Cwajg et al. (32) Mixed 109 Echo 0.87 0.86 0.72 2001 Vourvouri et al. (33) CAD with LV dysfunction 32 Echo 0.94 0.96 0.83 2000 Paul et al. (34) Mixed 15 ERNA (tomographic) 0.99 0.99 0.97 2000 Chua et al. (35) CAD with large defect 62 ERNA (planar) 0.88 0.95 0.94 MI = myocardial infarction; LVG = contrast left ventriculography; Echo = echocardiography.
Reference Patients No. of patients No. of segments GSPECT evaluation Modality of comparison Exact agreement, κ value Year Author RWM SWT 1997 Gunning et al. (38) Mixed 28 252 Visual, SQ MRI 78%, 0.66 78%, 0.62 1999 Tadamura et al. (27) CAD 20 180 Visual, SQ MRI 84%, 0.73 87%, 0.76 1999 Tadamura et al. (39) After CABG 16 128 Visual, SQ MRI NA 76%, 0.62 2001 Wahba et al. (40) CAD 21 273 Visual, SQ MRI 84%, 0.72 86%, 0.77 1994 Chua et al. (41) CAD 40 640 Visual, SQ Echo 91%, 0.68 90%, 0.62 1997 Germano et al. (19) Mixed 79 1,580 Quantitative Visual, SQ GSPECT 73%, 0.43 75%, 0.41 2000 Sharir et al. (58) Mixed 100 2,000 Quantitative Visual, SQ GSPECT 80%, 0.71 86%, 0.68 κ = Cohen’s κ; SQ = semiquantitative; CABG = coronary artery bypass graft; NA = not available; Echo = echocardiography.
