Analysis of stress-only imaging, comparing upright and supine CZT camera acquisition to conventional gamma camera images with and without attenuation correction, with coronary angiography as a reference.

BACKGROUND

Diagnostic performance of stress-only imaging using a Cadmium-Zinc-Telluride (CZT) camera has not been directly compared in the same patients to stress-only attenuation-corrected conventional Anger camera images.

METHODS

112 subjects with correlative coronary angiographic data and 40 subjects with <5% pre-test likelihood of coronary disease completed attenuation-corrected stress-only images on a conventional Anger camera and uncorrected upright and supine stress images on a CZT camera. Two readers provided independent, blinded interpretations of stress-only images.

RESULTS

Upright and supine stress-only CZT images and attenuation-corrected Anger camera images provided similar positive (reader 1/reader 2, 50.0%/44.1% vs 46.4%/51.9%) and negative (66.7%/64.0% vs 67.9%/67.7%) predictive values (all P = NS) for obstructive coronary artery disease; however, the sensitivity was higher (81.3% vs 58.3%, P = .05), specificity lower (29.7% vs 50.0%, P = .005), and normalcy rate lower (87.5% vs 100%, P = .025) with attenuation-corrected Anger camera images for the first reader with no significant differences between cameras for the second reader.

CONCLUSIONS

Stress-only upright and supine CZT imaging was non-inferior statistically to attenuation-corrected stress-only Anger camera imaging. Nevertheless, stress-only CZT imaging may be associated with reduced diagnostic sensitivity for some readers compared to attenuation-corrected Anger camera images, which may be less acceptable clinically compared to stress plus rest images.