An Unusual ECG Finding during Adenosine Stress Myocardial Perfusion Imaging

Adenosine is extensively utilized in myocardial stress perfusion imaging for the detection and risk stratification of coronary artery disease. It has a well-established safety profile. The majority of the undesirable effects experienced during adenosine infusion are transient (owing to its brief half-life of ~10 s) and arise from the stimulation of receptors in the atrio-ventricular (AV) node (AV block) and bronchial smooth muscles (bronchospasm). We hereby report an unusual electrocardiographic finding during adenosine stress perfusion imaging, in a patient who had previously undergone single chamber pacemaker insertion and was referred for the assessment of atypical chest pain.