Effect of Pacing on Aortic dP/dt Values

Measurements will be performed in patients otherwise undergoing invasive catheterization procedure. Baseline ventricular and aortic hemodynamic parameters (continuous pressure recordings) will be recorded. Thereafter, DDD pacing with stepwise changing of the AV delay will be performed. During each pacing steps left ventricular and aortic pressures at different aortic levels will be continuously recorded. From these hemodynamic data, left ventricular and aortic dP/dt values will be calculated off line.