The influence of angiographically successful coronary angioplasty (PTCA) in 27 patients (mean age 64 +/- 8 years) was assessed by means of 0.018" intracoronary Doppler guidewire. Averaged peak flow velocity (APV) and diastolic-systolic velocity ratio (DSVR) were recorded in resting conditions (bas) and during papaverine induced hyperemia before and after PTCA. Coronary flow reserve (CFR) was calculated as ratio of hyperemic and resting APV. The parameters mentioned above were estimated proximally and distally to coronary stenosis to be dilated. Mean value of APVbas for distal part of the vessels was significantly lower (about 46-57%) then for the two proximal segments. PTCA caused significant increase of APVbas as for proximal (about 21-69%) as for distal segments (about 62-77%). That procedure caused significant increase of CFR only for right coronary artery (RCA). Mean values of DSVRbas in proximal position for left descendens (LAD) and left circumflex (LCx) arteries before PTCA were significantly higher than DSVbas for distal position but did not differ for RCA. PTCA caused significant increase of DSVRbas in distal position only for LAD and LCx. Our results showed that angiographically successful PTCA causes significant increase of APVbas for right and left coronary arteries and normalization of DSVRbas in distal segments of LAD and LCx.