Background: Intravenous adenosine in conjunction with myocardial perfusion imaging is
commonly used for the detection of coronary artery disease and risk assessment. We have
previously shown that patients with ischemic changes on the 12-lead electrocardiogram (ECG)
in response to adenosine but with normal perfusion pattern have a benign outcome on shortintermediate
follow-up. The long-term outcome of these patients is unknown.
Methods: Patients with ischemic ECG response (≥ 1 mm ST depression) to adenosine
infusion but with normal perfusion on single-photon emission computed tomography (SPECT)
imaging in the absence of a history of myocardial infarction or coronary revascularization
were followed up for mortality, myocardial infarctions, and coronary revascularization.
Results: The cohort consisted of 73 patients (81% women) who were followed up for mortality
for a mean of 61 ± 15 months. There were 10 deaths, and the cause of death was determined to be
non-cardiac in half of those. Follow-up for the other endpoints was complete for 21 ± 10 months
during which no patient had myocardial infarction and seven underwent coronary
revascularization.
Conclusions: Patients with ischemic ECG response to intravenous adenosine administration
and normal perfusion on SPECT are at low risk of cardiovascular events. The ST segment
response to adenosine in this setting is likely related to non-ischemic mechanisms
