The purpose of the present study was to determine the effect of β-blockade-induced bradycardia and normofrequent ventricular pacing (VP) on regional myocardial (MBF) and cerebral blood flow (CBF) as well as on myocardial oxygen consumption (MVO<sub>2</sub>) using colored microspheres. The MBF at sinus rhythm (SR) was 4.60 ± 1.27 ml/g/min and decreased to 3.80 ± 0.74 ml/g/min (p < 0.05) during β-blockade. The MBF was 5.10 ± 1.88 ml/g/min during VP with β-blockade. The endo-/epicardial MBF ratio during VP was significantly reduced. MVO<sub>2</sub> at β-blockade was significantly lower (0.21 ± 0.06 ml/g × min<sup>–1</sup>, p < 0.05) than at SR (0.47 ± 0.15 ml/g × min<sup>–1</sup>) and during VP with β-blockade (0.54 ± 0.14 ml/g × min<sup>–1</sup>). Results: (i) MBF and MVO<sub>2</sub> are reduced with decreasing mean arterial pressure (MAP) during β-blockade-induced bradycardia, but MBF and MVO<sub>2</sub> are significantly increased during normofrequent VP with β-blockade despite a further reduction in MAP. (ii) The MBF ratio is constant during β-blockade but is significantly lower during normofrequent VP with β-blockade. (iii) CBF remained constant during all experimental conditions. Conclusion: Despite β-blockade, the subendocardium is jeopardized during normofrequent VP by ischemia.