Effects of percutaneous transluminal coronary angioplasty on lesion-associated branches.

To assess the effects of percutaneous transluminal coronary angioplasty (PTCA) on lesion-associated branches, angiograms from 100 consecutive angioplasties involving 109 lesion dilatations were analyzed. Ninety-seven lesion-associated branches occurred in 76 (70%) of the dilated stenoses. Sixty-six (68%) branches were small (less than or equal to 1 mm) and 31 (32%) were moderate (greater than 1 mm) in size. Pre-PTCA branch ostial narrowing was present in 52 (54%), whereas there was no ostial disease in 45 (46%). Decreased ostial lumen occurred in 16 (16%) branches following angioplasty. Decreases in branch ostia were significantly more frequent in branches with preexisting branch disease (14 of 52, 27%) compared to branches with normal pre-PTCA ostia (2 of 45, 4%; p less than or equal to 0.01). However, vessel size, PTCA success, gender, and lesion dissection did not predict likelihood of branch ostial changes. Seven branches became totally or subtotally occluded following PTCA, one after unsuccessful and six following successful dilatation. Of the latter six, three experienced chest discomfort and one had an elevated creatine kinase with myocardial band, but no patient had immediate ECG changes. In summary, although moderate- or small-sized branches frequently accompany PTCA lesions, branch changes following angioplasty are infrequent and occur most often in branches with preexisting ostial disease.