title: Acute results, complications, and effect of lesion characteristics on outcome with the solid-state, pulsed-wave, mid-infrared laser angioplasty system: final multicenter registry report. Holmium:YAG Laser Multicenter Investigators.
abstract: OBJECTIVE
  The solid-state, mid-infrared holmium:YAG laser (2.1 microm wavelength) is a relatively new percutaneous device that has recently been evaluated in a multicenter study. Because of its unique wavelength and photoacoustic effects on atherosclerotic plaques, this laser may be useful in treatment of symptomatic patients with coronary artery disease. This study sought to evaluate the safety and efficacy of mid-infrared laser angioplasty in the treatment of coronary artery lesions.
  
  
  METHODS
  Laser angioplasty was performed on 2,038 atherosclerotic lesions in 1,862 consecutive patients with a mean age of 61 +/- 11 years. Clinical indications included unstable angina (69%), stable angina (20%), acute infarction (6%), and positive exercise test (5%). Complex lesion morphology included eccentricity (62%), thrombus (30%), total occlusion (27%), long lesions (14%), and saphenous vein grafts (11%).
  
  
  RESULTS
  This laser catheter alone successfully reduced stenosis (>20%) in 87% of lesions. With adjunct balloon angioplasty, 93% procedural success was achieved. The presence of thrombus within the target lesion was a predictor of procedural success (OR = 2.0 [95% confidence interval 2.0, 4.0], P = .04). Bifurcation lesions (OR = 0.5 [95% confidence interval 0.2, 1.0], P = .05) and severe tortuosity of the treated vessel (OR = 0.4 [95% confidence interval 0.2, 0.9], P = .02) were identified as significant predictors of decreased laser success. Calcium within the lesion was associated with reduced procedural success (OR = 0.57 [95% confidence interval 0.34, 0.97], P = .03), and calcified lesions required significantly more energy pulses than noncalcified lesions (119 +/- 91 pulses vs. 101 +/- 86 pulses, respectively, P = .0002). Complications included in-hospital bypass surgery 2.5%, Q-wave myocardial infarction 1.2%, and death 0.8%. Perforation occurred in 2.2% of patients; major dissection in 5.8% of patients, and spasm in 12% of patients. No predictor of major complications was identified. Six-month angiographic restenosis was documented in 54% of patients, and clinical restenosis occurred in 34% of patients.
  
  
  CONCLUSIONS
  Mid-infrared laser has a safety profile similar to that of other debulking devices. This laser may be useful in select patients presenting with acute ischemic syndromes associated with intracoronary thrombus; however, like other coronary lasers, it is limited by the need for adjunctive balloon angioplasty and/or stenting to achieve adequate final luminal diameter. No beneficial effects on reducing 6-month restenosis rates were observed.
authors.affiliation: Division of Cardiology, McGuire VA Medical Center, Medical College of Virginia Hospitals, Medical College of Virginia, Richmond 23249, USA.
authors.forename: O
authors.initials: O
authors.lastname: Topaz
authors.forename: M
authors.initials: M
authors.lastname: McIvor
authors.forename: G W
authors.initials: GW
authors.lastname: Stone
authors.forename: M W
authors.initials: MW
authors.lastname: Krucoff
authors.forename: E C
authors.initials: EC
authors.lastname: Perin
authors.forename: A E
authors.initials: AE
authors.lastname: Foschi
authors.forename: J
authors.initials: J
authors.lastname: Sutton
authors.forename: R
authors.initials: R
authors.lastname: Nair
authors.forename: E
authors.initials: E
authors.lastname: deMarchena
mesh_terms: D000538:Aluminum Silicates; D000787:Angina Pectoris / Q000601:surgery; D000789:Angina, Unstable / Q000601:surgery; D017222:Angioplasty, Balloon, Laser-Assisted; D016342:Angioplasty, Laser / Q000009:adverse effects / Q000379:methods; D002114:Calcinosis / Q000601:surgery; D001026:Coronary Artery Bypass; D003324:Coronary Artery Disease / Q000601:surgery*; D003328:Coronary Thrombosis / Q000601:surgery; D003329:Coronary Vasospasm / Q000209:etiology; D003331:Coronary Vessels / Q000293:injuries; D005069:Evaluation Studies as Topic; D005260:Female; D005544:Forecasting; D006083:Graft Occlusion, Vascular / Q000601:surgery; D006695:Holmium; D006801:Humans; D007259:Infrared Rays; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000601:surgery; D012008:Recurrence; D012042:Registries; D012449:Safety; D012501:Saphenous Vein / Q000637:transplantation; D016896:Treatment Outcome; D015019:Yttrium
chemical_list: D000538:Aluminum Silicates; D015019:Yttrium; D006695:Holmium