Clinical Presentation

A 74-year-old man with known coronary artery disease (CAD) and prior myocardial infarction (MI) is referred for a dipyridamole myocardial perfusion PET study for post-MI evaluation. Cardiac risk factors include hypertension and dyslipidemia. The resting ECG shows normal sinus rhythm and anterior and lateral Q waves. Medications include a β-blocker, an angiotensin-converting enzyme inhibitor, aspirin, a statin, and clopidogrel.

Fig. 42.1

Fig. 42.2

• The patient had nothing to eat within 4 hours of the test. The β-blocker was withheld on the day of the test. Caffeinated beverages were withheld for 24 hours before the test.

• After a scout computed tomographic (CT) acquisition (120 kVp, 10 mA) for patient positioning, a CT transmission scan (140 kVp, 30 mA, pitch of 1.35) was acquired for attenuation correction. Commercial software was used for coregistration of the transmission and emission images.

• Rest emission images were obtained for 5 minutes after the intravenous administration of 60 mCi of ⁸²Rb at rest, with imaging starting 120 seconds (given the low ejection fraction) after completion of the radionuclide infusion. Rest gated images were acquired at 8 frames per cycle.

• PET images were reconstructed with ordered subsets expectation maximization (OSEM; 2 iterations and 30 subsets), and a three-dimensional PET filter was used (Butterworth filter cutoff frequency of 10, order of 5).

• Vasodilator stress was achieved with a standard intravenous infusion of dipyridamole (0.14 mg/kg per minute) for 4 minutes.

• The patient was injected with 60 mCi of ⁸²