title: Strategies for the reduction of cerebral microembolism during transmyocardial laser revascularization.
abstract: OBJECTIVE
  During transmyocardial laser revascularization (TMLR), multiple microembolic signals (MES) can be detected in cerebral arteries. We sought to characterize composition and clinical relevance of these MES and to evaluate strategies to reduce cerebral microembolization during TMLR.
  
  
  METHODS
  TMLR was performed in pigs. Laser energy was set to 4-10 J (group A) or 80 J (group B). Oxygen concentration was varied between 21 and 100%. MES were recorded in the ophthalmic artery. Brain and spinal cord were investigated histologically after 10 days.
  
  
  RESULTS
  More MES could be detected during high- compared to low-energy laser procedures. Ventilation with 100% oxygen reduced the number of MES. No lesions were found on histology.
  
  
  CONCLUSIONS
  The number of MES depends on the laser energy. Laser-induces cavitation-effects lead to an additional release of nitrogen bubbles. Thus, the microembolic load can be reduced by ventilation with 100% oxygen and by decreasing the laser energy.
authors.affiliation: Department of Neurology, Justus-Liebig University Giessen, 35390 Giessen, Germany.
authors.forename: Tibo
authors.initials: T
authors.lastname: Gerriets
authors.forename: Martin
authors.initials: M
authors.lastname: Grossherr
authors.forename: Martin
authors.initials: M
authors.lastname: Misfeld
authors.forename: Urs
authors.initials: U
authors.lastname: Nees
authors.forename: Ernst
authors.initials: E
authors.lastname: Reusche
authors.forename: Erwin
authors.initials: E
authors.lastname: Stolz
authors.forename: Hans H
authors.initials: HH
authors.lastname: Sievers
authors.forename: Manfred
authors.initials: M
authors.lastname: Kaps
authors.forename: Ernst G
authors.initials: EG
authors.lastname: Kraatz
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology; D004453:Echoencephalography; D020766:Intracranial Embolism / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D053685:Laser Therapy / Q000009:adverse effects* / Q000379:methods; D009204:Myocardial Revascularization / Q000009:adverse effects* / Q000379:methods; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D013552:Swine
chemical_list: D010100:Oxygen