Cardiac SPECT (Myocardial Perfusion)

Gated myocardial perfusion imaging with Tc-99m sestamibi or tetrofosmin under rest and pharmacologic or exercise stress. Historically the workhorse non-invasive ischemia test; now competing with coronary CTA, stress echo, stress MRI, and Rb-82 PET. Dedicated cardiac CZT cameras (D-SPECT, GE Discovery NM 530c) cut acquisition time and dose substantially versus general-purpose Anger cameras.

Clinical pathway

1. Stress acquisition — exercise treadmill or pharmacologic (regadenoson, dobutamine), inject at peak stress, image 15–60 min later.
2. Rest acquisition — separate injection, image after 60-min uptake.
3. Gated acquisition — ECG-gated SPECT for wall motion, thickening, EF.
4. Reporting — reversible vs fixed defects, transient ischemic dilation, EF.

Typical systems

• GE Discovery NM/CT 670 (general purpose)
• GE Discovery NM 530c (dedicated cardiac CZT)
• Spectrum Dynamics D-SPECT (dedicated cardiac CZT)
• Siemens Symbia Intevo

Room + procedure characteristics

• Total visit: 2–4 hours (one-day rest-stress protocol) or split over two days
• Dose: ~8–12 mSv (Tc-99m), higher with thallium
• Team: nuclear cardiologist + tech + stress RN

Related

• Cardiac Rb-82 PET
• PCI