[Hemodynamic effects of ipratropium bromide in comparison with atrial stimulation]

After application of ipratropium bromide (Itrop) a long-time increase of frequency and left ventricular ejection time can be observed. Beside a vagolytic effect a sympathomimetic action of the drug could be demonstrated by experimental investigations. In 10 patients hemodynamics in comparison to arteficial atrial pacing and after parenteral administration of 0.5 mg ipratropium bromide were investigated. The intervention by the drug led to an increase of heart rate from 54 to 93 beats/min. Cardiac index showed an increase from 2.40 to 2.96 l/min/m2, while stroke volume decreased from 82.0 to 59.1 ml. Compared to hemodynamic parameters measured under atrial pacing at the same heart rate no significant differences could be found. It could be demonstrated, that ipratropium bromide showed no positive inotropic effect of clinical relevance. The increase of cardiac index is referred to an augmented cardiac output due to a rise of heart rate.