Coronary revascularization in heart transplant recipients by excimer laserangioplasty

Background and Objective: Aggressive development of allograft coronary arte ry disease is a major cause of death in heart transplant recipients. Percut aneous balloon angioplasty is considered suboptimal for complex lesions in native coronary vessels and heart transplant recipients, alike. Excimer las er energy (308-nm wavelength) can successfully remove and vaporize atherosc lerotic plaques in native coronary vessels; however, its application in hea rt transplant recipients has not been studied clinically yet. Study Design/Materials and Methods: Six heart transplant recipients underwe nt percutaneous excimer laser (CVX-300, Spectranetics, Colorado Springs, CO ) coronary angioplasty for treatment of a total of 10 discrete, obstructive coronary artery lesions. By using concentric or eccentric multifiber laser catheters, energy parameters were set at a fluence of 45 mJ/mm(2) or 60 mJ /mm(2) with a frequency of 25 Hz and 40 Hz, respectively, with a pulse dura tion of 135 ns and output of 200 mJ/pulse. The "saline flush" and "pulse an d retreat" lasing techniques were used. In each case, adjunct balloon angio plasty was performed; in five lesions, an intracoronary stent was implanted . Angiographic evaluation was performed by visual assessment. Results: Each procedure was successful as defined by laser recanalization o f the target lesion (reduction of target lesion stenosis in more than 20%) and subsequent adequate final luminal patency (reduction of target lesion s tenosis to less than 50%) and absence of any major in-cardiac catheterizati on complication (such as perforation, acute closure, dissection, emergency coronary artery bypass surgery), or in-hospital complications (such as deat h, myocardial infarction, cardiac enzyme elevation, major bleeding), or nee d for surgical revascularization. A 92 +/- 5% preprocedural percent diamete r stenosis was reduced by laser to 35 +/- 16% and by adjunct balloon angiop lasty in all lesions and stenting in five lesions, to final residual stenos is of 2 +/- 6%. Angiographic follow-up between 2 and 6 months after the pro cedure demonstrated a target lesion restenosis rate of 22%. Conclusion: Percutaneous excimer laser is safe and efficacious in the treat ment of focal obstructive lesions caused by allograft coronary artery disea se. These data represent an early clinical experience; thus, the long-term outcome of this revascularization method in recipients of heart transplanta tion will have to be determined by a large scale prospective, randomized, m ulticenter clinical study. (C) 2000 Wiley-Liss, Inc.