Optimization of adenosine stress for myocardial perfusion imaging. - Optimization of adenosine stress

Myocardial blood flow (MBF) during caffeine intake and restriction was evaluated using MRI. The adenosine stress was increased stepwise until an increase in heart rate of more than 10 bpm, which is a common index of stress, was achieved. The index was achieved in all subjects even when caffeine was consumed, but the number of subjects who required increased adenosine was significantly higher than when caffeine was restricted. Mean MBF was significantly lower during caffeine intake than during restriction.