Reducing Radioisotope Dose: the Half-Dose CZT Study

The aim of this study is to compare the image quality of the half radioisotope dose scans obtained using a CZT (cadmium zinc telluride) camera with scans acquired using a standard of care imaging protocol/radioisotope dose performed on a traditional (conventional) camera.

The proposed strategy of a half dose/extended time protocol with the CZT camera should yield a similar count activity and consequently image quality equivalent to that detected by a conventional SPECT system.

Inclusion criteria

• ≥ 18 years of age and referred for a clinically-indicated stress SPECT MPI study
• suspected or known coronary artery disease
• written informed consent

Exclusion criteria

• Evidence of a normal baseline scan after at least 50% of the protocol acquired baseline scans have been interpreted as being normal
• Participation in another investigational study within the preceding month
• Pregnant and/or breast-feeding female
• ECG evidence of left bundle branch block or paced rhythm
• Evidence of non-ischemic cardiomyopathy
• Presence of hypertrophic cardiomyopathy and/or severe valvular heart disease
• Severe claustrophobia or inability to lie flat for 20 minutes (the anticipated amount of time to complete the procedure)
• Known allergy to technetium-99m
• Potential contraindications to regadenoson use, due to severe lung disease; severe bradycardia (heart rate < 40 beats/min); second- or third degree atrioventricular heart block; sick sinus syndrome; long QT syndrome; severe hypotension; or decompensated heart failure.