Figure 2 Transaxial positron emission tomography flow images obtained at rest and during dipyridamole (Dip) infusion in a representative patient before (pre‐C) and after treatment (post‐C) with carvedilol are shown (left panel). Absolute myocardial blood flow (MBF) value profiles, together with ((%MBF rest)−(%MBF Dip)) values (R‐D%), in the six left ventricular myocardial regions are also reported before (white colour) and after treatment (red colour; right panel). Before treatment, Dip increased the maldistribution of regional MBF already present at rest, causing stress‐induced flow defects more evident in the posterolateral wall (regions 1–2). After treatment, resting MBF was actually reduced in particular in the posterolateral wall, whereas Dip MBF was increased, in particular in the posterolateral wall, and stress‐inducible regional flow defects were no longer present.