PURPOSE--To evaluate the success rate and complications, as well as the technical difficulties involved catheter laser coronary angioplasty, making evident the unsuccessful cases. METHODS--Twenty eight patients were treated with laser from August to November, 1993. The treatment was complemented with balloon angioplasty.

Lesions were complex:

10 (36 per cent) were type B and 18 (64 per cent), type C. Concerning the obstruction grade, 18 (64 per cent) were > or = 95 per cent. Laser generator CVX 300(TM) Spectranectics as well as Extreme(TM) and Vitesse(TM) catheters with 1.4, 1.7 and 2.0mm in diameter, concentric and excentric, were used. Laser procedure success was defined as a reduction > 20 per cent in the obstruction grade. The procedure success was attended when the residual stenosis was < 50 per cent after a 15-minute observation, after balloon complementation. RESULTS--The unsuccess rate with laser catheter (Lc) was 34 per cent (10 lesions) of which 3 cases were solved by other methods, 5 were not successful because of anatomic difficulties in surpassing the lesion and, in the two others the success criterium in the reduction of the obstruction grade of the coronary artery was not achieved, although the lesion surpassing was possible with the use of balloon catheter. The final success reached 89 per cent (21 lesions). The procedure complications were a case of thrombosis, a perforation accompanied by a myocardial infarction and another myocardial infarction (non-Q wave), all with good outcome. CONCLUSION--The use of laser in the treatment of coronary artery obstructive lesions is a viable method. Nonetheless, more experience is necessary to demonstrate its actual value, optimizate the results and may be reduce restenosis rate