Significant breast uptake of Tc-99m sestamibi in an actively lactating woman during SPECT myocardial perfusion imaging

✍ Scribed by Gautam Ramakrishna; Todd D. Miller

• Publisher: Springer
• Year: 2004
• Tongue: English
• Weight: 68 KB
• Volume: 11
• Category: Article
• ISSN: 1071-3581
• DOI: 10.1016/j.nuclcard.2003.10.002

✦ Synopsis

Systematic analysis of the rotating cinematic raw images derived from single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is performed to assess for patient motion, cardiac size, and proximity of extracardiac structures that may affect interpretation of the short-and long-axis views (eg, breast attenuation or increased bowel/hepatic signal interference). 1 However, unexpected radioisotope uptake in noncardiac structures may also be observed and, in some instances, may prompt further evaluation to rule out malignancy. 2 We report a unique case of diffuse bilateral breast uptake in a woman 6 weeks post partum.

Case history. A 34-year-old woman had a normal spontaneous vaginal delivery, but a transient episode of sinus bradycardia developed 6 hours later (heart rate, 40-45 beats/min). Her cardiovascular history was significant only for mitral valve prolapse with mild mitral regurgitation. While the patient was walking to the shower, brief lightheadedness and transient substernal chest discomfort developed suddenly. This was specifically not associated with sudden movement or a distended bladder. The 12-lead electrocardiogram revealed sinus bradycardia at 44 beats/min without evidence for acute ischemic ST-segment or T-wave changes. Complete blood count, electrolyte, and sensitive thyroidstimulating hormone levels were unremarkable. The cardiac troponin T level was less than 0.01 ng/mL (normal troponin T level, Ͻ0.03 ng/mL) on two serial measurements.

Further evaluation included exercise sestamibi. The patient exercised for 9.5 minutes via a Bruce protocol, achieving a peak double product of 19,200. The stress electrocardiogram was negative for ischemia, and technetium 99m sestamibi SPECT images were negative for stress-induced ischemia or infarct.