ANGIOGRAPHIC RESULTS AND ELASTIC RECOIL FOLLOWING CORONARY EXCIMER-LASER ANGIOPLASTY WITH SALINE PERFUSION

Recent experiments have demonstrated that pressure waves of several hu ndred atmospheres, which occur during excimer laser coronary angioplas ty (ELCA), are reduced while ablating in saline in comparison to blood or contrast medium. We report the procedure outcome of ELCA (XeCl las er operating at 308 nm, 25-40 Hz, 40-60 mJ/mm(2) fluence, and 135 nsec /pulse) performed with a modified saline infusion protocol (two operat or technique, flush, and continuous application of saline through the guiding catheter immediately prior and during the whole lasing procedu re). We studied 48 patients (34 males, 14 females; mean age: 61 +/- 6 years; 18 occlusions, 30 stenoses [> 60% diameter stenosis]) with 10 t ype A, 17 type B, and 21 type C lesions. Laser success (> 20% increase in minimal luminal diameter [MLD]) was achieved by 41 patients (85.4% ), and procedural success (< 50% residual stenosis) in 44 patients (91 .6%). The MLD increased from 0.37 +/- 0.12 to 1.63 +/- 0.35 mm (P < 0. 001) following laser ablation, and to 2.30 +/- 0.34 mm (P < 0.01) afte r percutaneous transluminal coronary angioplasty (PTCA). The mean perc entage stenosis decreased from 81% +/- 6% (baseline) to 48% +/- 12% (P < 0.001) after laser ablation, and to 29% +/- 10% (P < 0.01) followin g PTCA. The mean diameter of the laser catheter (LC) was 1.54 +/- 0.2 and the mean diameter of the inflated balloon at maximum pressure was 2.7 +/- 0.25 mm. Thus, the elastic recoil (ER) following balloon defla tion was 15% +/- 9%, and below the reported ER for PTCA. Two major dis sections occured following ELCA; one patient required bypass surgery a nd developed a Q wave myocardial infarction (MI), and one patient was successfully treated with stent implantation following abrupt closure. There were no in-hospital deaths, further Q wave Mls, and/or perforat ion. In conclusion, ELCA with concomitant saline infusion is effective , safe, and easy to perform. The use of this ablation procedure reduce s the rate of significant dissections, favors effective tissue ablatio n, and thus may in part be responsible for a reduced amount of elastic recoil following additional balloon angioplasty.