Upward creep of the heart: A frequent source of false-positive reversible defects during thallium-201 stress-redistribution SPECT
- Cedars-Sinai Medical Center, Los Angeles, CA (USA)
A new cause of artifactual {sup 201}Tl defects on single photon emission computed tomography (SPECT) termed upward creep of the heart is described. In 102 consecutive patients undergoing {sup 201}Tl SPECT, 30 (29%) demonstrated upward creep defined by an upward movement of the heart of greater than or equal to 2 pixels during acquisition. In 45 consecutive patients with a less than 5% likelihood of coronary artery disease, 17 (38%) had upward creep. Of these nine had reversible {sup 201}Tl defects localized to the inferior and basal inferoseptal walls, while none of the 28 without upward creep had defects. The 17 low likelihood patients with upward creep had longer exercise duration and higher peak heart rate than those without upward creep. In five additional low likelihood patients with upward creep in whom imaging was immediately repeated, the upward creep pattern disappeared on the repeated images. After we changed our test protocol to begin imaging 15 min postexercise, only five (14%) of 36 low likelihood patients tested demonstrated upward creep. Upward creep is probably related to a transient increase in mean total lung volume early following exhaustive exercise, resulting in a mean lower position of the diaphragm (and thus the heart) at the beginning of imaging. The frequency of this source of false-positive {sup 201}Tl studies can be reduced by delaying SPECT acquisition until 15 min postexercise.
- OSTI ID:
- 5158914
- Journal Information:
- Journal of Nuclear Medicine; (USA), Vol. 30:10; ISSN 0161-5505
- Country of Publication:
- United States
- Language:
- English
Similar Records
Correction for patient and organ movement in SPECT: application to exercise thallium-201 cardiac imaging
Correction for patient and organ movement in SPECT: application to exercise thallium-201 cardiac imaging
Related Subjects
CARDIOVASCULAR DISEASES
DIAGNOSIS
HEART
SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY
EXERCISE
PATIENTS
THALLIUM 201
BETA DECAY RADIOISOTOPES
BODY
CARDIOVASCULAR SYSTEM
COMPUTERIZED TOMOGRAPHY
DAYS LIVING RADIOISOTOPES
DIAGNOSTIC TECHNIQUES
DISEASES
ELECTRON CAPTURE RADIOISOTOPES
EMISSION COMPUTED TOMOGRAPHY
HEAVY NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANS
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
THALLIUM ISOTOPES
TOMOGRAPHY
550601* - Medicine- Unsealed Radionuclides in Diagnostics