The determination of left systolic time intervals by electrical impedance plethysmography, using precordial pick-up electrodes, gives as good results as classical method using phonocardiogramm and carotid pulse trace. Moreover the measurement of right systolic time intervals is possible with this method. Another advantage of this technic is that it only requires affixing four electrocardiographic electrodes to the thorax and is usable during relatively long periods of time. The value of the basal thoracic impedance provides also a mean of following intrathoracic fluid changes and an early detection of pulmonary oedema, pleural effusion or hemorrage into the chest. So, cardiac impedance plethysmography appears as a good tool for cardiac monitoring.