Hemodynamic effects of lidoflazine during graded levels of bicycle exercise in normal subjects.

The hemodynamic effects of lidoflazine were studied in 12 young healthy subjects who received the drug orally (240 mg daily) for 8 weeks. During exercise after lidoflazine, heart rate (-2.6%), mean arterial pressure (-3.1%), arterio-venous oxygen (A-V02) difference (-3.4%), pressure rate product (-6.2%), and systemic vascular resistance (-8.6%) were significantly lower, while cardiac output (+5.4%) and stroke volume (+8.3%) were significantly greater. The maximal heart rate was lower after lidoflazine (-6 beats/min) but the maximal oxygen intake (VO2max) was not affected by the drug. The major hemodynamic effects of lidoflazine appear to be, on the one hand, an unexplained decrease in heart rate, and on the other, a decrease in systemic vascular resistance; the latter, which was expected from a vasodilator, could account for the greater stroke volume and contributes to the decrease of the pressure rate product. Lidoflazine has another unexplained effect, i.e. a decrease of the A-VO2 difference, suggesting a decreased peripheral extraction of oxygen at rest as well as during submaximal and maximal exercise.