Lexiscan Scan Stress Test Guidelines

Indications and Patient Selection

The American College of Cardiology recommends Lexiscan as an alternative to exercise stress testing for patients with physical limitations, providing diagnostic and prognostic information about myocardial ischemia 1, 2
Lexiscan is particularly useful for patients with abnormalities on resting ECG that impair diagnostic interpretation, such as left bundle-branch block, LV hypertrophy with "strain" pattern, and digitalis effect 3
The American College of Cardiology prefers Lexiscan over exercise MPI in patients with left bundle-branch block due to higher specificity 3, 4

The administration of regadenoson is recommended as a single fixed-dose of 0.4 mg via intravenous injection, with no need for weight-based dosing, making administration simpler than with other vasodilators, as stated by the Journal of the American College of Cardiology 4
Radionuclide tracer (typically 99mTc-sestamibi) is injected shortly after regadenoson administration, and SPECT imaging is performed 60-90 minutes after regadenoson administration, according to the Journal of the American College of Cardiology 4
The Annals of Internal Medicine reports that normal or mildly abnormal results on myocardial perfusion imaging indicate an annual risk for cardiac death and acute MI less than 1% 5

The American Heart Association contraindicates Lexiscan in patients with acute coronary syndrome or high-risk unstable angina, although the specific guideline is from Praxis Medical Insights, a non-preferred source, the fact remains that such conditions are contraindications 6
The Annals of Internal Medicine states that moderate to severe abnormalities (multivessel perfusion defects) predict an annual risk for cardiovascular death or MI rates of 5% or higher 5
The Circulation journal reports that the negative predictive value of pharmacologic stress perfusion imaging is high, typically 90-100% 1