Click on image to view larger version.

Figure 1 Study design for first and second internal cardioversion of chronic and recurrent AF. Beginning with a test shock of 60-V intensity, the voltage was increased in 40-V steps until cardioversion was achieved or to a maximum voltage of 580/240 V. The patients were sedated orally with 2.5 to 5 mg diazepam. Immediately before cardioversion, 1 mg midazolam was administered intravenously. Patients were asked to quantify their level of perceived pain by means of a scale ranging from 0 (= not felt) to 10 (= intolerable) after each shock applied.