title: Caffeine reduces the sensitivity of vasodilator MPI for the detection of myocardial ischaemia: Pro.
abstract: Caffeine is a non-selective antagonist at the adenosine receptors, which is expected to reverse both the intended (coronary vasodilation) and unintended (hypotension, flushing) effects of exogenously administered adenosine and adenosine-related compounds. In the past, several studies were conducted to characterize the effect of caffeine on vasodilator myocardial perfusion imaging (MPI) with conflicting results. However, new evidence supports earlier observations and shows that recent caffeine intake attenuates vasodilator-induced myocardial hyperaemia and may therefore reduce the sensitivity of radionuclide MPI for the detection of inducible perfusion abnormality in patients with coronary artery disease. Although the magnitude of this effect and hence its clinical significance are dose dependent, the acute response to equivalent doses of caffeine varies largely among individuals, and this might be explained by differences in caffeine exposure and genetically determined variations in caffeine metabolism. Abstinence from caffeinated foods and beverages for a minimum of 12 hours before vasodilator stress is therefore recommended although longer abstention might be required in order to prevent the potentially blocking effect of residual caffeine on vasodilator-mediated actions.
authors.affiliation: Nuclear Medicine Department, Royal Brompton and Harefield Hospitals, Sydney Street, London, SW3 6NP, United Kingdom. e.reyes@rbht.nhs.uk.
authors.forename: Eliana
authors.initials: E
authors.lastname: Reyes
mesh_terms: D000284:Administration, Oral; D002110:Caffeine / Q000008:administration & dosage*; D004347:Drug Interactions; D019317:Evidence-Based Medicine; D006801:Humans; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging*; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014665:Vasodilator Agents / Q000008:administration & dosage*
chemical_list: D014665:Vasodilator Agents; D002110:Caffeine
keywords: Caffeine; SPECT; vasodilator stress