Reducing Radioisotope Dose: the Half-Dose CZT Study

Reducing Radioisotope Dose in Regadenoson SPECT Myocardial Perfusion Imaging: Comparison of Half-Dose Scans Using a Novel Solid-State-Detector Dedicated Cardiac Camera to Full Dose Scans Acquired On Standard Equipment

This is a pilot study to see whether cardiac imaging can be performed using half the standard dose of radioisotope.

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.