Bronchofiberoscopy is one of the basic diagnostic tools in pulmonary care. It is therefore of interest to assess the effects of this procedure on circulatory system as well as the risk of possible cardiovascular complications. The study included 56 patients for whom bronchoscopy was a planned diagnostic procedure (9 patients had additionally BAL). Each patient's examination protocol included, among others, ECG by Holter method, the measurement of arterial pressure and 12-lead ECG performed before and after the examination. The patients were divided into two groups: those with ventricular arrhythmia diagnosed by ECG at rest and those without arrhythmia signs in ECG done prior to bronchofiberoscopy. The analysis of data revealed that bronchofiberoscopy was associated with considerable increase of arterial pressure in both groups of patients as well as with increased ventricular arrhythmia, particularly in patients with previous history of arrhythmia. Additional load upon the respiratory system exerted by BAL did not have a significant effect on the circulatory system.