Myocardial Perfusion SPECT Periprocedural Care

Updated: Aug 26, 2021
  • Author: Ricardo Cardona, MD; Chief Editor: Mahan Mathur, MD  more...
  • Print
Periprocedural Care

Patient Preparation

Dynamic exercise

Dynamic exercise is the stress technique of choice in patients with suspected or known CAD, provided that the patient is able to exercise at an acceptable workload (≤85% of the maximum predicted heart rate). [41, 42]

The patient should withdraw from drugs that may interfere with a physiologic exercise response. Beta antagonists and calcium channel antagonists should be discontinued for 5 half-lives before the test unless medically contraindicated. Patients should avoid caffeine-containing foods, beverages, and drugs for a minimum of 12 hours before the test. This allows the use of vasodilator agents in cases where the exercise is terminated and pharmacologic stress is undertaken. Patients should be instructed to dress appropriately for exercise. Fasting is not essential. Although many centers routinely fast patients before imaging, the advantages of this policy is unproven.

Pharmacologic stress

Pharmacologic stress is an excellent alternative to dynamic exercise. Pharmacologic stress with vasodilators is the procedure of choice for patients unable to exercise adequately [43] or for those with LBBB or paced rhythm. [44]

Patients stressed with the vasodilators adenosine or dipyridamole (vasodilator stress) must abstain from caffeinated foods, beverages, and drugs for a minimum of 12 hours before the test and preferably for 24 hours. [45] Aminophylline and theophylline must be stopped 24 hours before the test. [46] Patients on dipyridamole should discontinue the drug for a minimum of 24 hours before vasodilator stress.

Patients stressed with dobutamine should stop beta antagonists for 5 half-lives or at least 24 hours before the test unless contraindicated.

No anesthesia is required before SPECT testing.


The patient should be supine with both arms above the head, as shown below.

Positioning. The patient should be supine with bot Positioning. The patient should be supine with both arms above the head. Courtesy of Philips Healthcare.

Knee support may also be helpful because patient’s comfort is essential to minimize motion. Prone imaging has been used in some centers to reduce the incidence of inferior attenuation artifact [47] but can produce anterior artifacts and is not recommended in isolation.

Female patients should be imaged without underwear. A chest band can be used to minimize breast attenuation and to ensure reproducible positioning during later image acquisition.