Clinical Follow-up of Excimer Laser Coronary Angioplasty for In-stent Restenosis

BACKGROUND AND OBJECTIVES: revious studies have shown a high restenosis rate after balloon angioplasty for diffuse in-stent restenosis. Debulking strategy has been expected to be helpful to reduce the restenosis rate. This study evaluated the safety and long-term clinical event rate after excimer laser coronary angioplasty (ELCA) and adjunctive balloon angioplasty for in-stent restenosis. MATERIALS AND METHOD: We included 29 in-stent restenotic lesions treated in 28 patients (18 men, 10 women, mean age 60+/-2 years) admitted to Samsung Medical Center between June 1997 and August 1998. Quantitative coronary angiography was performed and clinical characteristics, acute complications, 30-day and 8-month major cardiac adverse event rate was analyzed. RESULTS: Initial success rate was 97%. We stopped the ELCA procedure in one lesion located in the proximal left anterior descending artery due to bradycardia and hypotension. In the 28 lesions successfully treated with ELCA and adjunctive balloon angioplasty, the minimal luminal diameter increased from 0.7+/-0.1 mm before ELCA to 1.9+/-0.1 mm after ELCA and to 2.7+/-0.1 mm after adjunctive balloon angioplasty (p<.0001). The acute luminal gain after ELCA was 60%. The diameter stenosis decreased from 75+/-2% before ELCA to 36+/-2% after ELCA and to 15+/-2% after adjunctive balloon angioplasty (p<.0001). There was no in-hospital death, Q wave acute myocardial infarction (AMI), emergency coronary artery bypass graft (CABG), but non-Q AMI was noted in 1 case (3%). During the followed-up period of 8 months, there were 1 death (4%) due to congestive heart failure, 1 nonQ-AMI (4%) and 7 target lesion revascularization (26%) among the successfully treated 27 patients, but there was no CABG, Q-AMI. Combined event rate at the 8-month follow-up was 33% and target lesion revascularization rate at 8-month follow-up was 26%. CONCLUSION: The ELCA and adjunctive balloon angioplasty seems to be safe and effective for the treatment of in-stent restenosis. A prospective randomized trial comparing ELCA versus other ablative technique is required.

The Effects of Excimer Laser Coronary Angioplasty in Calcified Lesions : Investigation with Intravascular Ultrasound

BACKGROUND: Coronary artery target lesion calcification may be an important determinant of the arterial response to catheter therapy for coronary arterial disease. The excimer laser coronary angioplasty(ELCA) has been reported to be a promising treatment for complex coronary artery disease. However, the effects of ELCA is not well known against the calcified target lesion. METHODS: To assess the arterial and plaque remodeling in calcified lesions after excimer laser coronary angioplasty, we used a comprehensive intravascular ultrasound(IVUS) imaging system(25MHz rotation transducer, 3.9 Fr monorail imaging sheath, motorized transducer pull back at 0.5mm/sec and quantification) to study 23 patients(1 left main, 10 LAD, 4 LCX, 6 RCA, 2 SVG) before and immediately after ELCA(the AIS 308nm XeCl excimer laser, pulse width >200nsec, pulse frequency 20Hz, energy density 35-65mJ/mm2). Paired before and after ELCA image slices were analysed ; and extermal elastic membrane, lumen, plaque+media(P+M) and calcium cross-sectional area(CSA) measured; and their differences after ELCA calculated. RESULTS: The IVUS results about the therapeutic effects of ELCA showed the enlargement of lumen CSA from 1.5+/-0.4 to 3.2+/-0.9mm2(p<0.001) and decreased of P+M CSA from 14.6+/-3.8 to 13.4+/-3.6mm2(p<0.001) without arterial expansion. The decrease of calcium CSA from 1.8+/-0.7 to 1.5+/-0.6mm2(p<0.001) and the formation of small, superficial fissures within the calcified plaque(15/23 lesions) were noted. The number of small fissures correlate with the calcium CSA significantly(r=0.61, p<0.001). CONCLUSION: The plaque and calcium ablation is the main effects of ELCA in calcified lesion, and the calcium ablation and fissure formation after ELCA may contribute to decrease the dissection and improve the success after ajunctive PTCA.