276 Pound Female

 

All images on this web page are displayed at default contrast settings.
No contrast enhancement or “background subtraction” has been performed.

History:  49 y/o woman. Prior stenosis of the right coronary artery, treated by angioplasty.

Current complaint:  Recurrent exertional chest pain similar to that before her angioplasty.

Height:   5' 0”

Weight:   276 pounds.  Very obese.

Dose:   26.2 mCi at peak treadmill stress

Timing:   Tracer was injected at peak treadmill exercise. After a 30 minute delay, SPECT images were obtained on a conventional, dual-detector, dedicated cardiac SPECT system. Approximately one hour later, images were obtained on the CardiArc® scanner. No additional tracer was administered between the two scans.

Acquisition Duration
Conventional
dual-detector w
LEHR collimation		 10.6 min
CardiArc® 3.3 min

Scan findings:   The CardiArc® images reveal an inferior and inferobasal defect consistant with re-stenosis of previously dilated right coronary artery - later verified. This is poorly visualized on the conventional system images, but is identified by quantitative analysis of those images (below).

Discussion:   The CardiArc® images have higher resolution, better target to background ration and less scatter than do same-day, same-injection images obtained with a conventional high-resolution, dual-detector system. These factors result in reduced partial-volume effect and higher lesion contrast.

p9166 Stress Short-axis
Conventional system - 10.6 min acquisition

20141k CArc stress short-axis
CardiArc® - 3.3 min acquisition


p9166 Stress vertical long-axis
Conventional system - 10.6 min acquisition

20141k CArc Stress vert long-axis
CardiArc® - 3.3 min acquisition


p9166 Stress horiz long-axis
Conventional system - 10.6 min acquisition

20141k CArc Stress Horiz long-axis
CardiArc® - 3.3 min acquisition


BullsEye plot of dual-detector data
Quantitative analysis of images from the dual-detector, conventional system identifies the same inferior / inferobasal abnormality (yellow arrows) seen visually on the CardiArc® images.

Final diagnosis: Recurrent stenosis of the right coronary artery.