Echocardiographic examination: in left lateral position after 10 minutes rest. The first examination: after a 2-hour non-smoking period, the second: immediately after smoking one cigarette containing 0.9 mg of nicotine. The duration of the second examination: no more than 15 minutes.

Echocardiography equipment: Hewlett-Packard SONOS 2000 (Andover, Massachusetts) imaging system. The transducer’s frequency: 2 MHz.

From the apical four chamber view the visualisation of transmitral flow, pulmonary venous flow and transtricuspid flow. From subcostal view the visualisation of right superior hepatic vein and the hepatic vein flow.

Inclusion Criteria:

• Smokers smoking over 10 cigarettes per day over the last 5 years
• Body mass index < 25 kg/m2
• Normal blood pressure and normal parameters of echocardiographic examination (wall thickness, left- and right- chamber size, valvular function and left and right ventricular systolic function)
• Normal results of routine physical examination, chest x-ray, standard rest electrocardiogram and routine laboratory tests.

Exclusion Criteria:

• Body mass index > 25 kg/m2
• Abnormal blood pressure
• Abnormal parameters of echocardiographic examination (wall thickness, left- and right- chamber size, valvular function and left and right ventricular systolic function)
• Abnormal results of routine physical examination, chest x-ray, standard rest electrocardiogram and routine laboratory tests.