Multidetector computed tomography (MDCT) has been demonstrated to be a very useful technique to non-invasively study coronary arteries. Despite the high spatial and temporal resolution of 64-slice MDCT scanners, this technique has several limitations. Dual-source computed tomography (DSCT) allows to study coronary arteries with excellent diagnostic quality in all subjects independent of the heart rate, thus avoiding the use of beta-blockers. In this article DSCT studies from three subjects with elevated heart rate and irregular heart rhythm are described. Usefulness of this technique to obtain studies of excellent quality in cases in which conventional 64-row-MDCT might present limitations is emphasized.