Nd:YAG laser-assisted angioplasty in femoropopliteal artery occlusions: "hot" versus "cold" recanalization with transparent contact probe.

Percutaneous recanalization of femoropopliteal artery occlusions (1-21 cm; median, 8 cm) was attempted in 50 patients. A 2.2-mm-diameter contact probe catheter connected to a continuous-wave neodymium yttrium aluminum garnet (Nd:YAG) laser was used. The laser was activated (15 W, 1-second pulses) only if too much resistance was met. Balloon angioplasty was performed after successful traversal of the occlusion. Primary success was achieved in 40 of 50 patients (80%). In 20 cases, recanalization was achieved mechanically (cold group). In the other 20 cases, recanalization was achieved with the help of laser irradiation (hot group: 15-405 J; median, 90 J). Except for the length of the obstruction (longer in the cold group), the two groups did not differ in baseline characteristics. Neither the length of the occlusion nor the duration of symptoms correlated with failure or success or with the delivered laser energy. Cold and hot groups did not differ with regard to functional improvement and angiographic patency at 3 and 12 months (94% +/- 4). Thus, brief laser activation doubled the cold primary success rate, but the major action of the laser contact probe is mechanical remodeling of the obstruction.